Today's Message Index:
----------------------
1. 12:45 AM - Re: IMC - What If??? Analysis (Kevin Horton)
2. 03:29 AM - Re: RV-8 (Deene Ogden)
3. 04:50 AM - Re: on wheel pants (Ralph E. Capen)
4. 04:55 AM - Re: IMC - What If??? Analysis (John Huft)
5. 05:39 AM - Re: Oil leak (bluesidedown)
6. 06:05 AM - Re: RV-8 (linn Walters)
7. 06:11 AM - Re: on wheel pants (Ron Lee)
8. 06:18 AM - Re: Re: Oil leak (Christopher Stone)
9. 11:12 AM - Re: IMC - What If??? Analysis (Bruce Gray)
10. 11:34 AM - Re: IMC - What If??? Analysis (John Huft)
11. 11:50 AM - Re: IMC - What If??? Analysis (Bruce Gray)
12. 11:55 AM - Re: IMC - What If??? Analysis (SteinAir, Inc.)
13. 12:12 PM - Re: IMC - What If??? Analysis (John Huft)
14. 12:26 PM - Re: IMC - What If??? Analysis (Bruce Gray)
15. 02:50 PM - Re: IMC - What If??? Analysis (RobHickman@AOL.COM)
16. 03:18 PM - Re: IMC - What If??? Analysis (Bruce Gray)
17. 05:03 PM - Re: IMC - What If??? Analysis (RobHickman@aol.com)
18. 06:17 PM - Re: IMC - What If??? Analysis (scott bilinski)
19. 10:38 PM - Question on Wood props (DEAN PSIROPOULOS)
20. 10:57 PM - Question on jam nuts (DEAN PSIROPOULOS)
Message 1
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Subject: | Re: IMC - What If??? Analysis |
As I understand it, this means that the pitch info comes from changes in
barometric altitude (i.e. VSI), enhanced with solid state pitch rate
"gyro" info. No GPS info is used for pitch or roll display.
Kevin Horton
Bruce Gray wrote:
> Hmmm, I could be wrong but.... The TruTrak website says the roll is
> instantaneous gyro and the pitch is enhanced VSI. Perhaps we're both right.
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com] On Behalf Of SteinAir, Inc.
> Sent: Wednesday, September 24, 2008 6:22 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> Hi Bruce,
>
> You know I agree with you historically on some of your points, but I have to
> jump in here just a little bit - nothing personal, just want to re-direct a
> few facts. Your understanding of the TruTrak ADI is not just a little bit
> off....it's just flat wrong. Who told you it uses GPS information for
> vertical information? They use GPS to show a track in the little LCD
> window...it has nothing to do with the flight display. You do of course
> realize that it has solid state gyros inside of it and shows instantaneous
> pitch and bank information as well? Naturally you also know that it has a
> Pitot and Static connection on the back of it to sense pitot/satic info? Of
> course some of the EFIS mfgrs out there use GPS as an aiding function to
> offset the accelerometer drift, etc.., but I'm not aware of any other than
> the little "instrument page" of the Garmin handhelds that do anything of the
> sort.
>
> Anyway, I don't want to get into a debate on what should be used when and
> where nor if the ADI is for you or not...just want to make sure people don't
> think it uses GPS to display any flight information. I do agree that there
> is a BIG question on lower cost EFISes knowing whether they are ill or not.
> The certified stuff has a ton of software in it for that very purpose, and
> will paint a big red "X" over any portion of the instrument it thinks
> doesn't has perfect information. Most of the really low cost EFISes will
> not alert you to anything being wrong, because the EFIS itself doesn't know
> it's sick. It's what I try to tell people over and over. There is a MUCH
> larger difference between EFISes than just plain cost. There is a lot of
> other unseen functionality that comes with the higher priced units other
> than their name on the faceplate. Of course every EFIS mfgr will tell you
> their stuff is the same as the certified Garmin or what is in the Boeings
> while standing in the booth at OSH (I actually heard a rep from a low cost
> EFIS mfgr repeatedly tell people their stuff was as good or better than the
> Garmin certified stuff)....hopefully people realize that's just not the case
> and couldn't be farther from the truth. Does that mean the low cost EFISes
> are bad? Heck no! They are a marvel of technology as long as you use them
> for what they are.
>
> FYI...most of the heavy iron is going to solid state peanut backups as
> well....but they aren't anything like our low cost EFISes (nor the price)!
>
> Again, nothing personal and I'm not necessarily disagreeing with premise in
> general, just some of the details. The whole "tie breaker" discussion gets
> really interesting really fast in some of these configurations. There are a
> number of historical crashes of airliners because of the fight between
> pilot/copilot and the "tie breaker" of instruments indications. Overall I
> could ramble on and on about this stuff, as well as the whole AHRS theory,
> but in the end we're all entitled to our own opinions. Like I said, no
> necessarily agreeing or disagreeing, just putting out a few facts.
>
> Cheers,
> Stein
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com]On Behalf Of Bruce Gray
> Sent: Wednesday, September 24, 2008 4:50 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> To play the devils advocate,
>
> You'll be lucky if, when your EFIS fails, the screen goes dark. More than
> likely, part of it will just freeze, or worse yet - start giving you false
> information.
>
> What do you do when all your electro-wizzies fail? It's happened - several
> times in big iron aircraft, failure of multiple electrical systems and their
> backups leaving a totally dark cockpit. One of the reasons that all EFIS
> certified panels have a vacuum ADI or equivalent.
>
> But let's look at a more likely failure mode, the AHRS starts to put out
> false information. Your Tru-Trak ADI (It's not really) only displays quasi
> pitch info. It shows a GPS derived VSI as pitch up/down commands. Now, the
> big question is - are you willing to bet your life that you addled and
> confused brain is going to be able to sort out the conflicting and non
> standard pitch information before you go "THUD"?
> And as your screaming brain is yelling - which system is right? Needle,
> ball, and airspeed tie breaker?
>
> I know I've spent hundreds of hours scanning the basic 6 pack in IMC and am
> well aware of its failure modes. But when screens go dark or scrambled it's
> the easiest and fasted for me to revert to and feel comfortable.
>
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
--
Kevin Horton
RV-8 (Flight Test Phase)
Ottawa, Canada
http://www.kilohotel.com/rv8
Message 2
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I made my curved RV8 front stick. Just layout on paper your desired curved
stick side profile (including any length reduction to clear the panel.don't
forget the stick grip length).
Then cut several (6 for me) small pie sections out along the back portion of
the stick and form the stick to the desired curve by gentle pressure. Now
tack weld the stick in the final shape and then weld up the joints. If you
can't weld or don't have the equipment, find a good one at a local EAA
meeting.
Rather than use a "S" shape I used an upside down question mark shape so
that I had only one curve to deal with. Don't know if the following ASCII
drawing works:
|
_|
/
/
|
|
Deene Ogden
EAA Tech Counselor/Flight Advisor
RV8 QB N299AD
Message 3
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Subject: | Re: on wheel pants |
Bert,
To align mine, I used the axle hole drilled out for the tow-bar - put the tow bar
through the drilled hole and you have 90% of the alignment accomplished.....all
you need to do is rotate it in place.
In my case, I marked the 'waterline' on the pant and according to the drawings,
the new brackets have a parallel line to the waterline on the plans. This will
allow you to fit everything together on the bench with the tire removed...put
the axlebolt back in, attach the towbar, rotate the waterline parallel to the
level line in the bracket. There should be enough room to back drill through
the bracket in to the pant.......
Ralph
-----Original Message-----
>From: bert murillo <robertrv607@yahoo.com>
>Sent: Sep 24, 2008 5:31 PM
>To: rv-list@matronics.com
>Subject: RV-List: on wheel pants
>
>Hello:
>
>I just received the new brackets, for the nose geat wheel pants, from Van's
>Now the big question, for some one very talented.... only....
>
>The pants I have are the old type non transparents, and they are painted white
of course...
>
>How AQm I going to measured?, some kind of jig magic.. etc... to align the
>new brackets, in order to drill, and install ????
>
>I only came with one solution, but I am sure, there must be an easier one...
>I do not want to have littles wholes all over, then I have to patch them up..
>
>One shot, and a precise one, lt has to be.....ANY ONE WANTS TO TAKE
>THIS CHALLENGE///
>
>Thanks for those brave ones, that respond...
>
>Bert
>
>rv6a
>
>do not archive
>
>
Message 4
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|
Subject: | IMC - What If??? Analysis |
The basic ADI (not with built in autopilot option) has a single gyro (solid
state rate gyro), inclined like the one in a turn coordinator. This means
the gyro itself senses both roll and azimuth changes (not position,
changes).
It also has pitot and static pressure inputs.
For vertical display, it is an IVSI, an instantaneous vertical speed
indicator, so it does not have the lag that a basic VSI has. This is a
common mechanical instrument, often used in gliders and seaplanes.
For bank angle information, it uses the turn rate info from the gyro, and
combines that with the speed info from the pitot input to calculate and
display bank angle. This is the basic patent that TT brags about.
John
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of Kevin Horton
Sent: Thursday, September 25, 2008 1:23 AM
Subject: Re: RV-List: IMC - What If??? Analysis
As I understand it, this means that the pitch info comes from changes in
barometric altitude (i.e. VSI), enhanced with solid state pitch rate
"gyro" info. No GPS info is used for pitch or roll display.
Kevin Horton
Bruce Gray wrote:
> Hmmm, I could be wrong but.... The TruTrak website says the roll is
> instantaneous gyro and the pitch is enhanced VSI. Perhaps we're both
right.
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com] On Behalf Of SteinAir, Inc.
> Sent: Wednesday, September 24, 2008 6:22 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> Hi Bruce,
>
> You know I agree with you historically on some of your points, but I have
to
> jump in here just a little bit - nothing personal, just want to re-direct
a
> few facts. Your understanding of the TruTrak ADI is not just a little bit
> off....it's just flat wrong. Who told you it uses GPS information for
> vertical information? They use GPS to show a track in the little LCD
> window...it has nothing to do with the flight display. You do of course
> realize that it has solid state gyros inside of it and shows instantaneous
> pitch and bank information as well? Naturally you also know that it has a
> Pitot and Static connection on the back of it to sense pitot/satic info?
Of
> course some of the EFIS mfgrs out there use GPS as an aiding function to
> offset the accelerometer drift, etc.., but I'm not aware of any other than
> the little "instrument page" of the Garmin handhelds that do anything of
the
> sort.
>
> Anyway, I don't want to get into a debate on what should be used when and
> where nor if the ADI is for you or not...just want to make sure people
don't
> think it uses GPS to display any flight information. I do agree that
there
> is a BIG question on lower cost EFISes knowing whether they are ill or
not.
> The certified stuff has a ton of software in it for that very purpose, and
> will paint a big red "X" over any portion of the instrument it thinks
> doesn't has perfect information. Most of the really low cost EFISes will
> not alert you to anything being wrong, because the EFIS itself doesn't
know
> it's sick. It's what I try to tell people over and over. There is a MUCH
> larger difference between EFISes than just plain cost. There is a lot of
> other unseen functionality that comes with the higher priced units other
> than their name on the faceplate. Of course every EFIS mfgr will tell you
> their stuff is the same as the certified Garmin or what is in the Boeings
> while standing in the booth at OSH (I actually heard a rep from a low cost
> EFIS mfgr repeatedly tell people their stuff was as good or better than
the
> Garmin certified stuff)....hopefully people realize that's just not the
case
> and couldn't be farther from the truth. Does that mean the low cost
EFISes
> are bad? Heck no! They are a marvel of technology as long as you use
them
> for what they are.
>
> FYI...most of the heavy iron is going to solid state peanut backups as
> well....but they aren't anything like our low cost EFISes (nor the price)!
>
> Again, nothing personal and I'm not necessarily disagreeing with premise
in
> general, just some of the details. The whole "tie breaker" discussion
gets
> really interesting really fast in some of these configurations. There are
a
> number of historical crashes of airliners because of the fight between
> pilot/copilot and the "tie breaker" of instruments indications. Overall I
> could ramble on and on about this stuff, as well as the whole AHRS theory,
> but in the end we're all entitled to our own opinions. Like I said, no
> necessarily agreeing or disagreeing, just putting out a few facts.
>
> Cheers,
> Stein
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com]On Behalf Of Bruce Gray
> Sent: Wednesday, September 24, 2008 4:50 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> To play the devils advocate,
>
> You'll be lucky if, when your EFIS fails, the screen goes dark. More than
> likely, part of it will just freeze, or worse yet - start giving you false
> information.
>
> What do you do when all your electro-wizzies fail? It's happened - several
> times in big iron aircraft, failure of multiple electrical systems and
their
> backups leaving a totally dark cockpit. One of the reasons that all EFIS
> certified panels have a vacuum ADI or equivalent.
>
> But let's look at a more likely failure mode, the AHRS starts to put out
> false information. Your Tru-Trak ADI (It's not really) only displays quasi
> pitch info. It shows a GPS derived VSI as pitch up/down commands. Now, the
> big question is - are you willing to bet your life that you addled and
> confused brain is going to be able to sort out the conflicting and non
> standard pitch information before you go "THUD"?
> And as your screaming brain is yelling - which system is right? Needle,
> ball, and airspeed tie breaker?
>
> I know I've spent hundreds of hours scanning the basic 6 pack in IMC and
am
> well aware of its failure modes. But when screens go dark or scrambled
it's
> the easiest and fasted for me to revert to and feel comfortable.
>
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
--
Kevin Horton
RV-8 (Flight Test Phase)
Ottawa, Canada
http://www.kilohotel.com/rv8
Message 5
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|
Reducing the pressure in the crankcase may help. I see a lot of breather tubes
on RVs butt up against the exhaust and I think why?? When all they would have
to do is weld a small pipe to the exhaust (at the right angle and depth) run
the breather tube to that and the benefits would be cleaner bottom, lower crankcase
pressure thus less leaks, less oil consumption and a slight but noticeable
increase in power. Prior to doing so myself I was skeptical of some radical
claims of doing so but I knew there was a reason for positive crankcase ventilation
and what the hec its experimental right!! My RV4 had a brand new 180hp
leakcoming and after I ran the breather to the exhausts the leaks ended and I
notice a slight gain in power. So I thought I would do the same with my Acrosport
1 with its tube ran all the way to the back of the plane and I was sure the
benefits would be greater and they were. I had over 50 RPM increase at full
throttle during a static run up. And no leaks!! Matter of fact the plane just
went coast to coast and did not need any oil. My latest plane with Angle valve
360 used to spew oil all over the bottom and the guy selling it to me told me
that when I bought it and it did. For on the trip home from Texas the bottom
was very oily and needed a quart in just 4 hours. So I did the same thing with
it and since then my front seal has not leaked anything and my accessory case
is far cleaner as is the bottom. I still get some oil but about a tenth of what
I used to and in 25 hours I only used one quart. I have a constant speed
prop on this one and so it is a little harder to measure but it feels a little
stronger. Anyway it seems the benefits are worth looking into. Now I have not
heard of or if there has been any problems and as with anything do some research
noting what others experienced and the best way to set it up. I am just telling
you about my experience.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p 6087#206087
Message 6
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|
You could also cut the desired 'bend' in hardwood to make a form and use
a hydraulic shop press to form the tube. Make the hardwood as thick as
the tube, and attach 'guides' to the sides of one of the pieces of form
so the other side slides into it. The slower you go with the pressure,
the less chance of getting a kink in the tubing.
Linn
do not archive
Deene Ogden wrote:
>
> I made my curved RV8 front stick. Just layout on paper your desired
> curved stick side profile (including any length reduction to clear the
> paneldont forget the stick grip length).
>
> Then cut several (6 for me) small pie sections out along the back
> portion of the stick and form the stick to the desired curve by gentle
> pressure. Now tack weld the stick in the final shape and then weld up
> the joints. If you cant weld or dont have the equipment, find a good
> one at a local EAA meeting.
>
> Rather than use a S shape I used an upside down question mark shape
> so that I had only one curve to deal with. Dont know if the following
> ASCII drawing works:
>
>
> _|
>
> /
>
> /
>
>
>
> Deene Ogden
>
> EAA Tech Counselor/Flight Advisor
>
> RV8 QB N299AD
>
> *
>
>
> *
Message 7
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|
Subject: | Re: on wheel pants |
I got everything aligned then filled the gaps and around the
brackets with flox. When cured take everything apart and
you can drill from the inside through holes already in the brackets
through the wheelpant.
Ron Lee
Message 8
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|
Have you pictures of the vent to exhaust configuration that you can share. Your
description refers to the
'right angle and depth", we all would like to know the details. I for one am interested
in keeping the bottom side clean and am installing an angle valve IO-360
in my RV-8.
Thanks!
Chris Stone
RV-8
Newberg, OR
-----Original Message-----
>From: bluesidedown <mbick@carolina.rr.com>
>Sent: Sep 25, 2008 8:39 AM
>To: rv-list@matronics.com
>Subject: RV-List: Re: Oil leak
>
>
>Reducing the pressure in the crankcase may help. I see a lot of breather tubes
on RVs butt up against the exhaust and I think why?? When all they would have
to do is weld a small pipe to the exhaust (at the right angle and depth) run
the breather tube to that and the benefits would be cleaner bottom, lower crankcase
pressure thus less leaks, less oil consumption and a slight but noticeable
increase in power. Prior to doing so myself I was skeptical of some radical
claims of doing so but I knew there was a reason for positive crankcase ventilation
and what the hec its experimental right!! My RV4 had a brand new 180hp
leakcoming and after I ran the breather to the exhausts the leaks ended and
I notice a slight gain in power. So I thought I would do the same with my Acrosport
1 with its tube ran all the way to the back of the plane and I was sure
the benefits would be greater and they were. I had over 50 RPM increase at full
throttle during a static run up. And no leaks!! Mat
!
> ter of fact the plane just went coast to coast and did not need any oil. My latest
plane with Angle valve 360 used to spew oil all over the bottom and the
guy selling it to me told me that when I bought it and it did. For on the trip
home from Texas the bottom was very oily and needed a quart in just 4 hours.
So I did the same thing with it and since then my front seal has not leaked anything
and my accessory case is far cleaner as is the bottom. I still get some
oil but about a tenth of what I used to and in 25 hours I only used one quart.
I have a constant speed prop on this one and so it is a little harder to measure
but it feels a little stronger. Anyway it seems the benefits are worth
looking into. Now I have not heard of or if there has been any problems and as
with anything do some research noting what others experienced and the best way
to set it up. I am just telling you about my experience.
>
>
>Read this topic online here:
>
>http://forums.matronics.com/viewtopic.php?p 6087#206087
>
>
Message 9
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|
Subject: | IMC - What If??? Analysis |
So, that means that there are some situations where the aircraft could be at
reduced power, level in pitch, in a decent, and the instrument would show
nose down causing the pilot to pitch up and stall the aircraft.
Bruce
www.Glasair.org
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of John Huft
Sent: Thursday, September 25, 2008 7:54 AM
Subject: RE: RV-List: IMC - What If??? Analysis
The basic ADI (not with built in autopilot option) has a single gyro (solid
state rate gyro), inclined like the one in a turn coordinator. This means
the gyro itself senses both roll and azimuth changes (not position,
changes).
It also has pitot and static pressure inputs.
For vertical display, it is an IVSI, an instantaneous vertical speed
indicator, so it does not have the lag that a basic VSI has. This is a
common mechanical instrument, often used in gliders and seaplanes.
For bank angle information, it uses the turn rate info from the gyro, and
combines that with the speed info from the pitot input to calculate and
display bank angle. This is the basic patent that TT brags about.
John
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of Kevin Horton
Sent: Thursday, September 25, 2008 1:23 AM
Subject: Re: RV-List: IMC - What If??? Analysis
As I understand it, this means that the pitch info comes from changes in
barometric altitude (i.e. VSI), enhanced with solid state pitch rate
"gyro" info. No GPS info is used for pitch or roll display.
Kevin Horton
Bruce Gray wrote:
> Hmmm, I could be wrong but.... The TruTrak website says the roll is
> instantaneous gyro and the pitch is enhanced VSI. Perhaps we're both
right.
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com] On Behalf Of SteinAir,
> Inc.
> Sent: Wednesday, September 24, 2008 6:22 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> Hi Bruce,
>
> You know I agree with you historically on some of your points, but I
> have
to
> jump in here just a little bit - nothing personal, just want to
> re-direct
a
> few facts. Your understanding of the TruTrak ADI is not just a little
> bit off....it's just flat wrong. Who told you it uses GPS information
> for vertical information? They use GPS to show a track in the little
> LCD window...it has nothing to do with the flight display. You do of
> course realize that it has solid state gyros inside of it and shows
> instantaneous pitch and bank information as well? Naturally you also
> know that it has a Pitot and Static connection on the back of it to
> sense pitot/satic info?
Of
> course some of the EFIS mfgrs out there use GPS as an aiding function
> to offset the accelerometer drift, etc.., but I'm not aware of any
> other than the little "instrument page" of the Garmin handhelds that
> do anything of
the
> sort.
>
> Anyway, I don't want to get into a debate on what should be used when
> and where nor if the ADI is for you or not...just want to make sure
> people
don't
> think it uses GPS to display any flight information. I do agree that
there
> is a BIG question on lower cost EFISes knowing whether they are ill or
not.
> The certified stuff has a ton of software in it for that very purpose,
> and will paint a big red "X" over any portion of the instrument it
> thinks doesn't has perfect information. Most of the really low cost
> EFISes will not alert you to anything being wrong, because the EFIS
> itself doesn't
know
> it's sick. It's what I try to tell people over and over. There is a
> MUCH larger difference between EFISes than just plain cost. There is
> a lot of other unseen functionality that comes with the higher priced
> units other than their name on the faceplate. Of course every EFIS
> mfgr will tell you their stuff is the same as the certified Garmin or
> what is in the Boeings while standing in the booth at OSH (I actually
> heard a rep from a low cost EFIS mfgr repeatedly tell people their
> stuff was as good or better than
the
> Garmin certified stuff)....hopefully people realize that's just not
> the
case
> and couldn't be farther from the truth. Does that mean the low cost
EFISes
> are bad? Heck no! They are a marvel of technology as long as you use
them
> for what they are.
>
> FYI...most of the heavy iron is going to solid state peanut backups as
> well....but they aren't anything like our low cost EFISes (nor the
> price)!
>
> Again, nothing personal and I'm not necessarily disagreeing with
> premise
in
> general, just some of the details. The whole "tie breaker" discussion
gets
> really interesting really fast in some of these configurations. There
> are
a
> number of historical crashes of airliners because of the fight between
> pilot/copilot and the "tie breaker" of instruments indications.
> Overall I could ramble on and on about this stuff, as well as the
> whole AHRS theory, but in the end we're all entitled to our own
> opinions. Like I said, no necessarily agreeing or disagreeing, just
> putting out a few facts.
>
> Cheers,
> Stein
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com]On Behalf Of Bruce Gray
> Sent: Wednesday, September 24, 2008 4:50 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> To play the devils advocate,
>
> You'll be lucky if, when your EFIS fails, the screen goes dark. More
> than likely, part of it will just freeze, or worse yet - start giving
> you false information.
>
> What do you do when all your electro-wizzies fail? It's happened -
> several times in big iron aircraft, failure of multiple electrical
> systems and
their
> backups leaving a totally dark cockpit. One of the reasons that all
> EFIS certified panels have a vacuum ADI or equivalent.
>
> But let's look at a more likely failure mode, the AHRS starts to put
> out false information. Your Tru-Trak ADI (It's not really) only
> displays quasi pitch info. It shows a GPS derived VSI as pitch up/down
> commands. Now, the big question is - are you willing to bet your life
> that you addled and confused brain is going to be able to sort out the
> conflicting and non standard pitch information before you go "THUD"?
> And as your screaming brain is yelling - which system is right?
> Needle, ball, and airspeed tie breaker?
>
> I know I've spent hundreds of hours scanning the basic 6 pack in IMC
> and
am
> well aware of its failure modes. But when screens go dark or scrambled
it's
> the easiest and fasted for me to revert to and feel comfortable.
>
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
--
Kevin Horton
RV-8 (Flight Test Phase)
Ottawa, Canada
http://www.kilohotel.com/rv8
Message 10
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|
Subject: | IMC - What If??? Analysis |
Bruce, you and I have been on these lists for at least 10 years now.
As you well know, this subject has been beaten into the ground.
Yes, if you are IFR, and you fixate on one instrument, there are many
different ways you can get in trouble. If you are going to fixate on a TT
ADI, to the exclusion of the airspeed indicator, you can get yourself into
the situation you describe.
I do have a TT ADI in my RV8. As an old CFII, I have been trained to fly
partial panel. I would far rather do it with an ADI and airspeed, than the
old needle, ball, and airspeed.
John
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of Bruce Gray
Sent: Thursday, September 25, 2008 12:10 PM
Subject: RE: RV-List: IMC - What If??? Analysis
So, that means that there are some situations where the aircraft could be at
reduced power, level in pitch, in a decent, and the instrument would show
nose down causing the pilot to pitch up and stall the aircraft.
Bruce
www.Glasair.org
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of John Huft
Sent: Thursday, September 25, 2008 7:54 AM
Subject: RE: RV-List: IMC - What If??? Analysis
The basic ADI (not with built in autopilot option) has a single gyro (solid
state rate gyro), inclined like the one in a turn coordinator. This means
the gyro itself senses both roll and azimuth changes (not position,
changes).
It also has pitot and static pressure inputs.
For vertical display, it is an IVSI, an instantaneous vertical speed
indicator, so it does not have the lag that a basic VSI has. This is a
common mechanical instrument, often used in gliders and seaplanes.
For bank angle information, it uses the turn rate info from the gyro, and
combines that with the speed info from the pitot input to calculate and
display bank angle. This is the basic patent that TT brags about.
John
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of Kevin Horton
Sent: Thursday, September 25, 2008 1:23 AM
Subject: Re: RV-List: IMC - What If??? Analysis
As I understand it, this means that the pitch info comes from changes in
barometric altitude (i.e. VSI), enhanced with solid state pitch rate
"gyro" info. No GPS info is used for pitch or roll display.
Kevin Horton
Bruce Gray wrote:
> Hmmm, I could be wrong but.... The TruTrak website says the roll is
> instantaneous gyro and the pitch is enhanced VSI. Perhaps we're both
right.
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com] On Behalf Of SteinAir,
> Inc.
> Sent: Wednesday, September 24, 2008 6:22 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> Hi Bruce,
>
> You know I agree with you historically on some of your points, but I
> have
to
> jump in here just a little bit - nothing personal, just want to
> re-direct
a
> few facts. Your understanding of the TruTrak ADI is not just a little
> bit off....it's just flat wrong. Who told you it uses GPS information
> for vertical information? They use GPS to show a track in the little
> LCD window...it has nothing to do with the flight display. You do of
> course realize that it has solid state gyros inside of it and shows
> instantaneous pitch and bank information as well? Naturally you also
> know that it has a Pitot and Static connection on the back of it to
> sense pitot/satic info?
Of
> course some of the EFIS mfgrs out there use GPS as an aiding function
> to offset the accelerometer drift, etc.., but I'm not aware of any
> other than the little "instrument page" of the Garmin handhelds that
> do anything of
the
> sort.
>
> Anyway, I don't want to get into a debate on what should be used when
> and where nor if the ADI is for you or not...just want to make sure
> people
don't
> think it uses GPS to display any flight information. I do agree that
there
> is a BIG question on lower cost EFISes knowing whether they are ill or
not.
> The certified stuff has a ton of software in it for that very purpose,
> and will paint a big red "X" over any portion of the instrument it
> thinks doesn't has perfect information. Most of the really low cost
> EFISes will not alert you to anything being wrong, because the EFIS
> itself doesn't
know
> it's sick. It's what I try to tell people over and over. There is a
> MUCH larger difference between EFISes than just plain cost. There is
> a lot of other unseen functionality that comes with the higher priced
> units other than their name on the faceplate. Of course every EFIS
> mfgr will tell you their stuff is the same as the certified Garmin or
> what is in the Boeings while standing in the booth at OSH (I actually
> heard a rep from a low cost EFIS mfgr repeatedly tell people their
> stuff was as good or better than
the
> Garmin certified stuff)....hopefully people realize that's just not
> the
case
> and couldn't be farther from the truth. Does that mean the low cost
EFISes
> are bad? Heck no! They are a marvel of technology as long as you use
them
> for what they are.
>
> FYI...most of the heavy iron is going to solid state peanut backups as
> well....but they aren't anything like our low cost EFISes (nor the
> price)!
>
> Again, nothing personal and I'm not necessarily disagreeing with
> premise
in
> general, just some of the details. The whole "tie breaker" discussion
gets
> really interesting really fast in some of these configurations. There
> are
a
> number of historical crashes of airliners because of the fight between
> pilot/copilot and the "tie breaker" of instruments indications.
> Overall I could ramble on and on about this stuff, as well as the
> whole AHRS theory, but in the end we're all entitled to our own
> opinions. Like I said, no necessarily agreeing or disagreeing, just
> putting out a few facts.
>
> Cheers,
> Stein
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com]On Behalf Of Bruce Gray
> Sent: Wednesday, September 24, 2008 4:50 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> To play the devils advocate,
>
> You'll be lucky if, when your EFIS fails, the screen goes dark. More
> than likely, part of it will just freeze, or worse yet - start giving
> you false information.
>
> What do you do when all your electro-wizzies fail? It's happened -
> several times in big iron aircraft, failure of multiple electrical
> systems and
their
> backups leaving a totally dark cockpit. One of the reasons that all
> EFIS certified panels have a vacuum ADI or equivalent.
>
> But let's look at a more likely failure mode, the AHRS starts to put
> out false information. Your Tru-Trak ADI (It's not really) only
> displays quasi pitch info. It shows a GPS derived VSI as pitch up/down
> commands. Now, the big question is - are you willing to bet your life
> that you addled and confused brain is going to be able to sort out the
> conflicting and non standard pitch information before you go "THUD"?
> And as your screaming brain is yelling - which system is right?
> Needle, ball, and airspeed tie breaker?
>
> I know I've spent hundreds of hours scanning the basic 6 pack in IMC
> and
am
> well aware of its failure modes. But when screens go dark or scrambled
it's
> the easiest and fasted for me to revert to and feel comfortable.
>
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
--
Kevin Horton
RV-8 (Flight Test Phase)
Ottawa, Canada
http://www.kilohotel.com/rv8
Message 11
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|
Subject: | IMC - What If??? Analysis |
OK, I'll stop. It's just that if it looks like an attitude gyro, unfamilure
pilots are going to try to fly it like one. I'm sure that if TruTrak tried
to certify that instrument, the FAA would require a "No Pitch Information"
placard.
Bruce
www.Glasair.org
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of John Huft
Sent: Thursday, September 25, 2008 2:34 PM
Subject: RE: RV-List: IMC - What If??? Analysis
Bruce, you and I have been on these lists for at least 10 years now.
As you well know, this subject has been beaten into the ground.
Yes, if you are IFR, and you fixate on one instrument, there are many
different ways you can get in trouble. If you are going to fixate on a TT
ADI, to the exclusion of the airspeed indicator, you can get yourself into
the situation you describe.
I do have a TT ADI in my RV8. As an old CFII, I have been trained to fly
partial panel. I would far rather do it with an ADI and airspeed, than the
old needle, ball, and airspeed.
John
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of Bruce Gray
Sent: Thursday, September 25, 2008 12:10 PM
Subject: RE: RV-List: IMC - What If??? Analysis
So, that means that there are some situations where the aircraft could be at
reduced power, level in pitch, in a decent, and the instrument would show
nose down causing the pilot to pitch up and stall the aircraft.
Bruce
www.Glasair.org
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of John Huft
Sent: Thursday, September 25, 2008 7:54 AM
Subject: RE: RV-List: IMC - What If??? Analysis
The basic ADI (not with built in autopilot option) has a single gyro (solid
state rate gyro), inclined like the one in a turn coordinator. This means
the gyro itself senses both roll and azimuth changes (not position,
changes).
It also has pitot and static pressure inputs.
For vertical display, it is an IVSI, an instantaneous vertical speed
indicator, so it does not have the lag that a basic VSI has. This is a
common mechanical instrument, often used in gliders and seaplanes.
For bank angle information, it uses the turn rate info from the gyro, and
combines that with the speed info from the pitot input to calculate and
display bank angle. This is the basic patent that TT brags about.
John
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of Kevin Horton
Sent: Thursday, September 25, 2008 1:23 AM
Subject: Re: RV-List: IMC - What If??? Analysis
As I understand it, this means that the pitch info comes from changes in
barometric altitude (i.e. VSI), enhanced with solid state pitch rate
"gyro" info. No GPS info is used for pitch or roll display.
Kevin Horton
Bruce Gray wrote:
> Hmmm, I could be wrong but.... The TruTrak website says the roll is
> instantaneous gyro and the pitch is enhanced VSI. Perhaps we're both
right.
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com] On Behalf Of SteinAir,
> Inc.
> Sent: Wednesday, September 24, 2008 6:22 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> Hi Bruce,
>
> You know I agree with you historically on some of your points, but I
> have
to
> jump in here just a little bit - nothing personal, just want to
> re-direct
a
> few facts. Your understanding of the TruTrak ADI is not just a little
> bit off....it's just flat wrong. Who told you it uses GPS information
> for vertical information? They use GPS to show a track in the little
> LCD window...it has nothing to do with the flight display. You do of
> course realize that it has solid state gyros inside of it and shows
> instantaneous pitch and bank information as well? Naturally you also
> know that it has a Pitot and Static connection on the back of it to
> sense pitot/satic info?
Of
> course some of the EFIS mfgrs out there use GPS as an aiding function
> to offset the accelerometer drift, etc.., but I'm not aware of any
> other than the little "instrument page" of the Garmin handhelds that
> do anything of
the
> sort.
>
> Anyway, I don't want to get into a debate on what should be used when
> and where nor if the ADI is for you or not...just want to make sure
> people
don't
> think it uses GPS to display any flight information. I do agree that
there
> is a BIG question on lower cost EFISes knowing whether they are ill or
not.
> The certified stuff has a ton of software in it for that very purpose,
> and will paint a big red "X" over any portion of the instrument it
> thinks doesn't has perfect information. Most of the really low cost
> EFISes will not alert you to anything being wrong, because the EFIS
> itself doesn't
know
> it's sick. It's what I try to tell people over and over. There is a
> MUCH larger difference between EFISes than just plain cost. There is
> a lot of other unseen functionality that comes with the higher priced
> units other than their name on the faceplate. Of course every EFIS
> mfgr will tell you their stuff is the same as the certified Garmin or
> what is in the Boeings while standing in the booth at OSH (I actually
> heard a rep from a low cost EFIS mfgr repeatedly tell people their
> stuff was as good or better than
the
> Garmin certified stuff)....hopefully people realize that's just not
> the
case
> and couldn't be farther from the truth. Does that mean the low cost
EFISes
> are bad? Heck no! They are a marvel of technology as long as you use
them
> for what they are.
>
> FYI...most of the heavy iron is going to solid state peanut backups as
> well....but they aren't anything like our low cost EFISes (nor the
> price)!
>
> Again, nothing personal and I'm not necessarily disagreeing with
> premise
in
> general, just some of the details. The whole "tie breaker" discussion
gets
> really interesting really fast in some of these configurations. There
> are
a
> number of historical crashes of airliners because of the fight between
> pilot/copilot and the "tie breaker" of instruments indications.
> Overall I could ramble on and on about this stuff, as well as the
> whole AHRS theory, but in the end we're all entitled to our own
> opinions. Like I said, no necessarily agreeing or disagreeing, just
> putting out a few facts.
>
> Cheers,
> Stein
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com]On Behalf Of Bruce Gray
> Sent: Wednesday, September 24, 2008 4:50 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> To play the devils advocate,
>
> You'll be lucky if, when your EFIS fails, the screen goes dark. More
> than likely, part of it will just freeze, or worse yet - start giving
> you false information.
>
> What do you do when all your electro-wizzies fail? It's happened -
> several times in big iron aircraft, failure of multiple electrical
> systems and
their
> backups leaving a totally dark cockpit. One of the reasons that all
> EFIS certified panels have a vacuum ADI or equivalent.
>
> But let's look at a more likely failure mode, the AHRS starts to put
> out false information. Your Tru-Trak ADI (It's not really) only
> displays quasi pitch info. It shows a GPS derived VSI as pitch up/down
> commands. Now, the big question is - are you willing to bet your life
> that you addled and confused brain is going to be able to sort out the
> conflicting and non standard pitch information before you go "THUD"?
> And as your screaming brain is yelling - which system is right?
> Needle, ball, and airspeed tie breaker?
>
> I know I've spent hundreds of hours scanning the basic 6 pack in IMC
> and
am
> well aware of its failure modes. But when screens go dark or scrambled
it's
> the easiest and fasted for me to revert to and feel comfortable.
>
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
--
Kevin Horton
RV-8 (Flight Test Phase)
Ottawa, Canada
http://www.kilohotel.com/rv8
Message 12
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|
Subject: | IMC - What If??? Analysis |
Bruce,
Now you're assuming someone will ignore the rest of the IFR scan - and not
pay attention to airspeed. If you're going to compare IMC apples to apples,
you can't use the entire scan for one objective review (your favorite old
Vac based gyro) and ignore it for the rest. Why would you randomly pull the
nose up at slow speed, reduced power in a descent?
I take it you haven't flown behind the instrument you're opining on
here.....
I know new things can be a bit scary, especially if you don't have first
hand knowledge of how they work. It'd be like me talking about how
Glasair's are to build or fly, when of course I haven't built one. It's
often the case with the ADI that pilots who haven't flown behind it or
understand it will have negative opinions about it, but I think youll find
that it's probably much better than you give it credit for once you actually
get some time behind one.
Again, nothing personal, but if you're going to compare apples to apples
then the entire scenario needs to be kept with the same comparisions/delta
between them. You can't throw out part of the information that you'd
normally use behind a gyro just to try and make the ADI look bad because you
personally don't happen to like it or fly behind it.
In the end, there is no doubt that Vacuum based gyros for the most parts
have and are going the way of the dinosaurs. You can either learn to adopt
to the new technology or not, but the world is going that way whether you
personally like it or not.
Cheers,
Stein
>-----Original Message-----
>From: owner-rv-list-server@matronics.com
>[mailto:owner-rv-list-server@matronics.com]On Behalf Of Bruce Gray
>Sent: Thursday, September 25, 2008 1:10 PM
>To: rv-list@matronics.com
>Subject: RE: RV-List: IMC - What If??? Analysis
>
>
>
>So, that means that there are some situations where the aircraft
>could be at
>reduced power, level in pitch, in a decent, and the instrument would show
>nose down causing the pilot to pitch up and stall the aircraft.
>
>Bruce
>www.Glasair.org
>
>
>do not archive
>
Message 13
INDEX | Back to Main INDEX |
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|
Subject: | IMC - What If??? Analysis |
That could be...it does work in a different way, and require a little bit of
re-education. It is a little like the change from the turn and bank
indicator to the turn coordinator, though more so, maybe.
I found it interesting to read that the attitude indicator in an SR-71 also
shows vertical speed rather than pitch...I guess a one-degree pitch up at
SR-71 speed would be extreme for altitude correction...same problem I have
at RV8 speeds :o)
John
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of Bruce Gray
Sent: Thursday, September 25, 2008 12:49 PM
Subject: RE: RV-List: IMC - What If??? Analysis
OK, I'll stop. It's just that if it looks like an attitude gyro, unfamilure
pilots are going to try to fly it like one. I'm sure that if TruTrak tried
to certify that instrument, the FAA would require a "No Pitch Information"
placard.
Bruce
www.Glasair.org
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of John Huft
Sent: Thursday, September 25, 2008 2:34 PM
Subject: RE: RV-List: IMC - What If??? Analysis
Bruce, you and I have been on these lists for at least 10 years now.
As you well know, this subject has been beaten into the ground.
Yes, if you are IFR, and you fixate on one instrument, there are many
different ways you can get in trouble. If you are going to fixate on a TT
ADI, to the exclusion of the airspeed indicator, you can get yourself into
the situation you describe.
I do have a TT ADI in my RV8. As an old CFII, I have been trained to fly
partial panel. I would far rather do it with an ADI and airspeed, than the
old needle, ball, and airspeed.
John
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of Bruce Gray
Sent: Thursday, September 25, 2008 12:10 PM
Subject: RE: RV-List: IMC - What If??? Analysis
So, that means that there are some situations where the aircraft could be at
reduced power, level in pitch, in a decent, and the instrument would show
nose down causing the pilot to pitch up and stall the aircraft.
Bruce
www.Glasair.org
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of John Huft
Sent: Thursday, September 25, 2008 7:54 AM
Subject: RE: RV-List: IMC - What If??? Analysis
The basic ADI (not with built in autopilot option) has a single gyro (solid
state rate gyro), inclined like the one in a turn coordinator. This means
the gyro itself senses both roll and azimuth changes (not position,
changes).
It also has pitot and static pressure inputs.
For vertical display, it is an IVSI, an instantaneous vertical speed
indicator, so it does not have the lag that a basic VSI has. This is a
common mechanical instrument, often used in gliders and seaplanes.
For bank angle information, it uses the turn rate info from the gyro, and
combines that with the speed info from the pitot input to calculate and
display bank angle. This is the basic patent that TT brags about.
John
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of Kevin Horton
Sent: Thursday, September 25, 2008 1:23 AM
Subject: Re: RV-List: IMC - What If??? Analysis
As I understand it, this means that the pitch info comes from changes in
barometric altitude (i.e. VSI), enhanced with solid state pitch rate
"gyro" info. No GPS info is used for pitch or roll display.
Kevin Horton
Bruce Gray wrote:
> Hmmm, I could be wrong but.... The TruTrak website says the roll is
> instantaneous gyro and the pitch is enhanced VSI. Perhaps we're both
right.
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com] On Behalf Of SteinAir,
> Inc.
> Sent: Wednesday, September 24, 2008 6:22 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> Hi Bruce,
>
> You know I agree with you historically on some of your points, but I
> have
to
> jump in here just a little bit - nothing personal, just want to
> re-direct
a
> few facts. Your understanding of the TruTrak ADI is not just a little
> bit off....it's just flat wrong. Who told you it uses GPS information
> for vertical information? They use GPS to show a track in the little
> LCD window...it has nothing to do with the flight display. You do of
> course realize that it has solid state gyros inside of it and shows
> instantaneous pitch and bank information as well? Naturally you also
> know that it has a Pitot and Static connection on the back of it to
> sense pitot/satic info?
Of
> course some of the EFIS mfgrs out there use GPS as an aiding function
> to offset the accelerometer drift, etc.., but I'm not aware of any
> other than the little "instrument page" of the Garmin handhelds that
> do anything of
the
> sort.
>
> Anyway, I don't want to get into a debate on what should be used when
> and where nor if the ADI is for you or not...just want to make sure
> people
don't
> think it uses GPS to display any flight information. I do agree that
there
> is a BIG question on lower cost EFISes knowing whether they are ill or
not.
> The certified stuff has a ton of software in it for that very purpose,
> and will paint a big red "X" over any portion of the instrument it
> thinks doesn't has perfect information. Most of the really low cost
> EFISes will not alert you to anything being wrong, because the EFIS
> itself doesn't
know
> it's sick. It's what I try to tell people over and over. There is a
> MUCH larger difference between EFISes than just plain cost. There is
> a lot of other unseen functionality that comes with the higher priced
> units other than their name on the faceplate. Of course every EFIS
> mfgr will tell you their stuff is the same as the certified Garmin or
> what is in the Boeings while standing in the booth at OSH (I actually
> heard a rep from a low cost EFIS mfgr repeatedly tell people their
> stuff was as good or better than
the
> Garmin certified stuff)....hopefully people realize that's just not
> the
case
> and couldn't be farther from the truth. Does that mean the low cost
EFISes
> are bad? Heck no! They are a marvel of technology as long as you use
them
> for what they are.
>
> FYI...most of the heavy iron is going to solid state peanut backups as
> well....but they aren't anything like our low cost EFISes (nor the
> price)!
>
> Again, nothing personal and I'm not necessarily disagreeing with
> premise
in
> general, just some of the details. The whole "tie breaker" discussion
gets
> really interesting really fast in some of these configurations. There
> are
a
> number of historical crashes of airliners because of the fight between
> pilot/copilot and the "tie breaker" of instruments indications.
> Overall I could ramble on and on about this stuff, as well as the
> whole AHRS theory, but in the end we're all entitled to our own
> opinions. Like I said, no necessarily agreeing or disagreeing, just
> putting out a few facts.
>
> Cheers,
> Stein
>
> -----Original Message-----
> From: owner-rv-list-server@matronics.com
> [mailto:owner-rv-list-server@matronics.com]On Behalf Of Bruce Gray
> Sent: Wednesday, September 24, 2008 4:50 PM
> To: rv-list@matronics.com
> Subject: RE: RV-List: IMC - What If??? Analysis
>
>
> To play the devils advocate,
>
> You'll be lucky if, when your EFIS fails, the screen goes dark. More
> than likely, part of it will just freeze, or worse yet - start giving
> you false information.
>
> What do you do when all your electro-wizzies fail? It's happened -
> several times in big iron aircraft, failure of multiple electrical
> systems and
their
> backups leaving a totally dark cockpit. One of the reasons that all
> EFIS certified panels have a vacuum ADI or equivalent.
>
> But let's look at a more likely failure mode, the AHRS starts to put
> out false information. Your Tru-Trak ADI (It's not really) only
> displays quasi pitch info. It shows a GPS derived VSI as pitch up/down
> commands. Now, the big question is - are you willing to bet your life
> that you addled and confused brain is going to be able to sort out the
> conflicting and non standard pitch information before you go "THUD"?
> And as your screaming brain is yelling - which system is right?
> Needle, ball, and airspeed tie breaker?
>
> I know I've spent hundreds of hours scanning the basic 6 pack in IMC
> and
am
> well aware of its failure modes. But when screens go dark or scrambled
it's
> the easiest and fasted for me to revert to and feel comfortable.
>
>
>
>
> Bruce
>
> <http://www.glasair.org/> www.Glasair.org
>
>
>
--
Kevin Horton
RV-8 (Flight Test Phase)
Ottawa, Canada
http://www.kilohotel.com/rv8
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Subject: | IMC - What If??? Analysis |
Well Stein, I'm certantly no Luddite, I even have a EHSI (Sandel 3500) on my
panel and a pair of those new fangled Garmin GPS thingies.
As I'm sure you know, from my previous posts, I'm NOT a fan of low cost
non-TSO'd EFIS systems. Even some of the low cost certified ones set my
teeth on edge. I'll just keep on spouting my mouth in hope that some of my
words will keep one of my brethern from an early grave.
For those that don't know, my rules for an EFIS panel are;
DO-178 certified software.
Dual independent AHRS with a cross comparator alarm system and an
independent third gyro attitude system as a tie breaker. Expensive - yep,
but it will keep you around to pay it off.
I sure hope we can keep this friendly, I'd hate to throw away my Stein-Air
tee shirt.
Bruce
www.Glasair.org
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of SteinAir, Inc.
Sent: Thursday, September 25, 2008 2:54 PM
Subject: RE: RV-List: IMC - What If??? Analysis
Bruce,
Now you're assuming someone will ignore the rest of the IFR scan - and not
pay attention to airspeed. If you're going to compare IMC apples to apples,
you can't use the entire scan for one objective review (your favorite old
Vac based gyro) and ignore it for the rest. Why would you randomly pull the
nose up at slow speed, reduced power in a descent?
I take it you haven't flown behind the instrument you're opining on
here.....
I know new things can be a bit scary, especially if you don't have first
hand knowledge of how they work. It'd be like me talking about how
Glasair's are to build or fly, when of course I haven't built one. It's
often the case with the ADI that pilots who haven't flown behind it or
understand it will have negative opinions about it, but I think youll find
that it's probably much better than you give it credit for once you actually
get some time behind one.
Again, nothing personal, but if you're going to compare apples to apples
then the entire scenario needs to be kept with the same comparisions/delta
between them. You can't throw out part of the information that you'd
normally use behind a gyro just to try and make the ADI look bad because you
personally don't happen to like it or fly behind it.
In the end, there is no doubt that Vacuum based gyros for the most parts
have and are going the way of the dinosaurs. You can either learn to adopt
to the new technology or not, but the world is going that way whether you
personally like it or not.
Cheers,
Stein
>-----Original Message-----
>From: owner-rv-list-server@matronics.com
>[mailto:owner-rv-list-server@matronics.com]On Behalf Of Bruce Gray
>Sent: Thursday, September 25, 2008 1:10 PM
>To: rv-list@matronics.com
>Subject: RE: RV-List: IMC - What If??? Analysis
>
>
>
>So, that means that there are some situations where the aircraft could
>be at reduced power, level in pitch, in a decent, and the instrument
>would show nose down causing the pilot to pitch up and stall the
>aircraft.
>
>Bruce
>www.Glasair.org
>
>
>do not archive
>
Message 15
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Subject: | Re: IMC - What If??? Analysis |
The Cirrus SR-22 has a mechanical Airspeed indicator, Altimeter and an
ELECTRIC artificial horizon as the backup instruments. The Cirrus also has
two
alternators and a dual buss electrical system. The Cirrus does not have an
y
vacuum backup instruments, however it does have a parachute as the ultimate
backup and it has been used after the screens went black.
In my RV-10 I have two Advanced deck EFIS units, each with their own AHRS
and air data, Digiflight II VSGV Autopilot, Garmin 496 (with GPS based
instrument page) and a wet compass.
Unlike the Garmin G900 system, each AFS screen has an internal battery that
will power the EFIS independently for over an hour in the event of an
electrical failure in the aircraft. The AFS EFIS setup in my RV-10 has dua
l AHRS,
airspeed and altimeters for cross checking between screens as a measure of
added safety. The G900 is a single AHRS and airdata system.
Like the Garmin G900, the AFS AHRS and its companion Remote Magnetometer ar
e
built in an FAA MIDO approved manufacturing facility, where automated
state-of-the-art dual-axis ovenized rate tables ($250,000 each), thermal ch
ambers
and Helmholtz cages perform extensive calibration, test and 100% verificati
on
of performance and reliability prior to being incorporated into the EFIS.
The AHRS-Magnetometer has three separate microprocessors that calculate and
verify proper operation with built-in test functions. If the AHRS built in
test routine detects an error, the EFIS will display a large red X on the
screen and can switch to another AHRS. If the EFIS=99s CPU detects
a cross
compare error between screens a warning is generated and the pilot is able
to
select the AHRS to use.
AFS has extensive experience writing certified software to DO-178. AFS is
responsible for the software development for the new Honeywell KFD-840 EFIS
.
In my RV-10 I have the following failure modes:
1. Aircraft Electrical System Failure
Use Internal EFIS batteries and Garmin 496 connected to EFIS for navigation
.
Select closest airport, should have over an hour of backup time.
2. Single AHRS detected failure
EFIS screens will switch to second AHRS
3. EFIS cross compare error
Use Autopilot, GPS, and Compass to select AHRS to use.
4. EFIS screen failure
Use second EFIS and Autopilot.
5. Dual EFIS screen failure
Use Autopilot, 496 GPS, and Compass for navigation. I have actually
practiced this under the hood. Just last week my instructor made me fly an
approach
under the hood using only the 496.
The lack of proper training, little or no recurrent training and poor
judgment are the real safety problems not the EFIS. Statistically the comp
onent
that is most likely to fail is between the pilot=99s ears. Anyone fl
ying IFR
needs to be trained and proficient at recognizing a failure and being able
to
fly the aircraft without it.
Anyone that truly believes that they are safer flying a standard =9C6
pack=9D
with a single vacuum pump IFR rather than my RV-10 panel setup needs to che
ck
the ventilation while being exposed to fiberglass fumes.
Rob Hickman
Advanced Flight Systems
**************Looking for simple solutions to your real-life financial
challenges? Check out WalletPop for the latest news and information, tips a
nd
calculators. (http://www.walletpop.com/?NCID=emlcntuswall00000001)
Message 16
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Subject: | IMC - What If??? Analysis |
I'm really not high on fiberglass fumes. It's the vynalester resin fumes
that will make you feel good though....
What's gonna happen when you're up there and a lighting bolt strikes
your RV
and fries all your electrical systems?
Guys... I'm not against EFIS systems or you desire to fly behind them. I
just want everyone to realize what risks they are taking.
Although we are getting down to unlikely situations here.
Bruce
www.Glasair.org <http://www.glasair.org/>
-----Original Message-----
From: owner-rv-list-server@matronics.com
[mailto:owner-rv-list-server@matronics.com] On Behalf Of
RobHickman@aol.com
Sent: Thursday, September 25, 2008 5:49 PM
Subject: Re: RV-List: IMC - What If??? Analysis
The Cirrus SR-22 has a mechanical Airspeed indicator, Altimeter and an
ELECTRIC artificial horizon as the backup instruments. The Cirrus also
has
two alternators and a dual buss electrical system. The Cirrus does not
have
any vacuum backup instruments, however it does have a parachute as the
ultimate backup and it has been used after the screens went black.
In my RV-10 I have two Advanced deck EFIS units, each with their own
AHRS
and air data, Digiflight II VSGV Autopilot, Garmin 496 (with GPS based
instrument page) and a wet compass.
Unlike the Garmin G900 system, each AFS screen has an internal battery
that
will power the EFIS independently for over an hour in the event of an
electrical failure in the aircraft. The AFS EFIS setup in my RV-10 has
dual
AHRS, airspeed and altimeters for cross checking between screens as a
measure of added safety. The G900 is a single AHRS and airdata system.
Like the Garmin G900, the AFS AHRS and its companion Remote Magnetometer
are
built in an FAA MIDO approved manufacturing facility, where automated
state-of-the-art dual-axis ovenized rate tables ($250,000 each), thermal
chambers and Helmholtz cages perform extensive calibration, test and
100%
verification of performance and reliability prior to being incorporated
into
the EFIS.
The AHRS-Magnetometer has three separate microprocessors that calculate
and
verify proper operation with built-in test functions. If the AHRS built
in
test routine detects an error, the EFIS will display a large red X on
the
screen and can switch to another AHRS. If the EFIS's CPU detects a
cross
compare error between screens a warning is generated and the pilot is
able
to select the AHRS to use.
AFS has extensive experience writing certified software to DO-178. AFS
is
responsible for the software development for the new Honeywell KFD-840
EFIS.
In my RV-10 I have the following failure modes:
1. Aircraft Electrical System Failure
Use Internal EFIS batteries and Garmin 496 connected to EFIS for
navigation.
Select closest airport, should have over an hour of backup time.
2. Single AHRS detected failure
EFIS screens will switch to second AHRS
3. EFIS cross compare error
Use Autopilot, GPS, and Compass to select AHRS to use.
4. EFIS screen failure
Use second EFIS and Autopilot.
5. Dual EFIS screen failure
Use Autopilot, 496 GPS, and Compass for navigation. I have actually
practiced this under the hood. Just last week my instructor made me fly
an
approach under the hood using only the 496.
The lack of proper training, little or no recurrent training and poor
judgment are the real safety problems not the EFIS. Statistically the
component that is most likely to fail is between the pilot's ears.
Anyone
flying IFR needs to be trained and proficient at recognizing a failure
and
being able to fly the aircraft without it.
Anyone that truly believes that they are safer flying a standard "6
pack"
with a single vacuum pump IFR rather than my RV-10 panel setup needs to
check the ventilation while being exposed to fiberglass fumes.
Rob Hickman
Advanced Flight Systems
_____
Looking for simple solutions to your real-life
f9382257x1200540686/aol?redir=http://www.walletpop.com/?NCID=emlcntus
wall686
/aol?redir=http://www.walletpop.com/?NCID=emlcntuswall00000001"
target="_blank">Check out WalletPop for the latest news and
information,
tips and calculators.
Message 17
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Subject: | Re: IMC - What If??? Analysis |
In a message dated 9/25/2008 3:20:39 P.M. Pacific Daylight Time,
Bruce@glasair.org writes:
What's gonna happen when you're up there and a lighting bolt strikes your RV
and fries all your electrical systems?
Without ground straps on your control surfaces and static wicks your
electronics could be the least of your problems.
Actually we spent a lot of time with the help of Crossbow designing in
lightning protection on the electrical connections that wire to the EFIS. Crossbow
has extensive experience with passing the lightning protection requirements
for certification. We have not actually done lightning verification testing
of our EFIS or the RV-10.
>From _http://www.lightningtech.com/d~ta/faq1.html_
(http://www.lightningtech.com/d~ta/faq1.html)
The last confirmed civilian plane crash that was directly attributed to
lightning in the U.S. was in 1967, when lightning caused a catastrophic fuel tank
explosion.
Most aircraft skins are made primarily of aluminum, which is a very good
conductor of electricity. By making sure that there are no gaps in this
conductive path, the engineer can assure that most of the lightning current will
remain on the exterior skin of the aircraft. Some modern aircraft are made of
advanced composite materials, which by themselves are significantly less
conductive than aluminum. In this case, the composites should be made with an
embedded layer of conductive fibers or screens designed to carry lightning
currents.
Looks to me like Bruce could have more problems than we do with this one,
even without an EFIS :)
Rob Hickman
Advanced Flight Systems
**************Looking for simple solutions to your real-life financial
challenges? Check out WalletPop for the latest news and information, tips and
calculators. (http://www.walletpop.com/?NCID=emlcntuswall00000001)
Message 18
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|
Subject: | Re: IMC - What If??? Analysis |
Now to stir the pot..............=0A=0AYou can protect electrical systems w
ith TVS diodes. =0A=0Ahttp://en.wikipedia.org/wiki/Transient_voltage_suppre
ssion_diode=0A=0AAnd yes I have read that they can be used for lightening s
trikes and are on communication equipment.=0A=0A Scott =0A=0A=0A=0A=0A=0A--
--- Original Message ----=0AFrom: Bruce Gray <Bruce@glasair.org>=0ATo: rv-l
ist@matronics.com=0ASent: Thursday, September 25, 2008 3:15:46 PM=0ASubject
: RE: RV-List: IMC - What If??? Analysis=0A=0AMessage =0AI'm really not hig
h on fiberglass fumes. =0AIt's the vynalester resin fumes that will make yo
u feel good =0Athough....=0A =0AWhat's gonna happen when you're up there an
d =0Aa lighting bolt strikes your RV and fries all your electrical =0Asyste
ms?=0A =0AGuys... I'm not against EFIS systems or you =0Adesire to fly behi
nd them. I just want everyone to realize what risks they are =0Ataking.=0A
=0AAlthough we are getting down to unlikely =0Asituations here.=0A =0A =0AB
ruce=0Awww.Glasair.org=0A =0A-----Original Message-----=0AFrom: owner-rv-li
st-server@matronics.com [mailto:owner-rv-list-server@matronics.com] On Beha
lf Of RobHickman@aol.com=0ASent: Thursday, September 25, 2008 5:49 PM=0ATo
: rv-list@matronics.com=0ASubject: Re: RV-List: IMC - What If??? Analysis
=0A=0AThe Cirrus SR-22 has a mechanical Airspeed indicator, Altimeter and
an ELECTRIC artificial horizon as the backup instruments. The Cirrus also
has two alternators and a dual buss electrical system. The Cirrus does n
ot have any vacuum backup instruments, however it does have a parachute as
the ultimate backup and it has been used after the screens went black.
=0A =0AIn my RV-10 I have two Advanced deck EFIS units, each with their ow
n AHRS and air data, Digiflight II VSGV Autopilot, Garmin 496 (with GPS ba
sed instrument page) and a wet compass. =0AUnlike the Garmin G900 system,
each AFS screen has an internal battery that will power the EFIS independe
ntly for over an hour in the event of an electrical failure in the aircraf
t. The AFS EFIS setup in my RV-10 has dual AHRS, airspeed and altimeters
for cross checking between screens as a measure of added safety. The G900
is a single AHRS and airdata system.=0ALike the Garmin G900, the AFS AHRS
and its companion Remote Magnetometer are built in an FAA MIDO approved ma
nufacturing facility, where automated state-of-the-art dual-axis ovenized
rate tables ($250,000 each), thermal chambers and Helmholtz cages perform
extensive calibration, test and 100% verification of performance and relia
bility prior to being incorporated into the EFIS. =0AThe AHRS-Magnetometer
has three separate microprocessors that calculate and verify proper operat
ion with built-in test functions. If the AHRS built in test routine detec
ts an error, the EFIS will display a large red X on the screen and can swi
tch to another AHRS. If the EFIS=92s CPU detects a cross compare error
between screens a warning is generated and the pilot is able to select the
AHRS to use.=0AAFS has extensive experience writing certified software to
DO-178. AFS is responsible for the software development for the new Honey
well KFD-840 EFIS.=0AIn my RV-10 I have the following failure modes:=0A1.
Aircraft Electrical System Failure=0AUse Internal EFIS batteries and G
armin 496 connected to EFIS for navigation. Select closest airport, shou
ld have over an hour of backup =0Atime.=0A =0A2. Single AHRS detected f
ailure=0AEFIS screens will switch to second AHRS =0A3. EFIS cro
ss compare error=0AUse Autopilot, GPS, and Compass to select AHRS to use.
=0A =0A4. EFIS screen failure=0AUse second EFIS and Autopilot.=0A =0A5
. Dual EFIS screen failure=0AUse Autopilot, 496 GPS, and Compass for n
avigation. I have actually practiced this under the hood. Just last week
my instructor made me fly an approach under the hood using only the 496.
=0AThe lack of proper training, little or no recurrent training and poor j
udgment are the real safety problems not the EFIS. Statistically the comp
onent that is most likely to fail is between the pilot=92s ears. Anyone f
lying IFR needs to be trained and proficient at recognizing a failure and
being able to fly the aircraft without it. =0AAnyone that truly believes
that they are safer flying a standard =936 pack=94 with a single vacuum p
ump IFR rather than my RV-10 panel setup needs to check the ventilation whi
le being exposed to fiberglass fumes.=0ARob Hickman=0AAdvanced Flight Sy
stems =0A=0A=0A=0A=0A________________________________=0A Looking for simpl
e solutions to your real-life f9382257x1200540686/aol?redir=http://www.w
alletpop.com/?NCID=emlcntuswall686/aol?redir=http://www.walletpop.com/?
NCID=emlcntuswall00000001" target="_blank">Check out WalletPop for the
latest news and information, tips and calculators.=0A=0A=0Ahref="http:/
/www.matronics.com/Navigator?RV-List">http://www.matronics.com/Navigator?RV
-List=0Ahref="http://forums.matronics.com">http://forums.matronics.com=0A
href="http://www.matronics.com/contribution">http://www.matronics.com/c
======0A=0A=0A
Message 19
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Subject: | Question on Wood props |
I purchased a new wood prop from Ed Sterba for my 180 hp RV-6A. I also
purchased the 2 inch machined aluminum spacer, crush plate and prop bolts
from Vans to complete the installation. When I received the prop I
discovered that the bolt holes in the wood needed to be filed out quite a
bit in order for some of the bolts to be able to line up with the holes in
the spacer and go through the spacer into the tapped flange on the
crankshaft. With the prop off of the engine these bolts holes now seem quite
sloppy. The enlarged portions of the bolt holes on the back of the prop
seem to fit very well over the drive pins with virtually no slop when the
prop is on the spacer. I've been told that the torque from a 180 hp engine
into a wood prop really puts a lot of back and forth stresses on it. Should
I be concerned about the enlarged bolt holes (when the drive pins fit
tightly) or do I just need to make sure the prop is properly torqued and
check it often? Thanks.
Dean Psiropoulos
RV-6A N197DM
Finally received my airworthiness certificate, woo hoo!
Message 20
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Subject: | Question on jam nuts |
I finished rigging my flaps a few weeks ago but discovered that the right
flap pushrod tube rides very close to the side skin when the flaps are
retracted (manual flaps). So close in fact that the sides of a jam nut
cause some interference such that the heim bearing at the top of assembly
(the flap arms connected to the handle) cannot go in to the u-shaped holder
at the end of the flap arm. If I try to push the bearing over to go into
the flap arm the jam nut touches the side skin and does not allow the top
bearing to move over any further (if I open up the side skin hole any higher
to clear the nut you'll see it on the outside of the airplane, ugly). This
is easily remedied by removing the jam nut and, since the pushrod tube moves
away from the side skin as the flaps are extended, there is never an
interference issue. I made the pushrod tube long enough that there is no
way it will ever spin off either heim bearing and I do have a jam nut at the
top of the tube (at the flap arm). My only concern is whether the jam at the
bottom is needed for extra strain relief on the pushrod tube. If you
recall, this is a thick wall aluminum tube that is threaded to accept the
heim bearings. Without the jam nut on the bottom bearing, all the stress
goes into the threads inside the tube. Whereas if there is a jam nut on the
bearing, some of the stresses are transferred to the entire wall thickness
of the tube. It would seem that having the jam nut on might help stave off
a failure of the pushrod tube that might occur without it. But....don't
know if I'm splitting hairs here. Is that what the jam nut is for? Will
there be a premature failure at that end of the tube if there is no jam nut?
Or...can I just fly without it? Thanks.
Dean Psiropoulos
RV-6A N197DM
First engine run this weekend.
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