Today's Message Index:
----------------------
1. 01:27 AM - Re: Autopilots vs. "The Right Stuff" (Michael Pereira)
2. 06:14 AM - Re: Autopilots vs. "The Right Stuff" (BobsV35B@aol.com)
3. 06:23 AM - Re: Autopilots vs. "The Right Stuff" (Robert L. Nuckolls, III)
4. 06:24 AM - Re: Autopilots vs. "The Right Stuff" (Robert L. Nuckolls, III)
5. 07:14 AM - Re: Air conditioning stuff for sale (Doug Baleshta)
6. 07:22 AM - Re: Autopilots vs. "The Right Stuff" (Michael Pereira)
7. 08:30 AM - Re: Autopilots vs. "The Right Stuff" (Robert L. Nuckolls, III)
8. 08:43 AM - Re: Autopilots vs. "The Right Stuff" (David LLoyd)
9. 09:48 AM - Re: Autopilots vs. "The Right Stuff" (jaybannist@cs.com)
10. 02:25 PM - Wild flights... 22 hr trip in an LSA over the Atlantic... (Jay Hyde)
11. 03:16 PM - Re: Electrical stuff for sale. (gr8matronics)
12. 04:20 PM - Re: The weak link (Michael Pereira)
13. 04:25 PM - transorbs (Joel Jacobs)
14. 05:15 PM - Re: The weak link (Matt Prather)
15. 05:44 PM - Re: transorbs (Matt Prather)
16. 06:14 PM - Re: Autopilots vs. "The Right Stuff" (Ernest Christley)
17. 06:43 PM - Re: Autopilots vs. "The Right Stuff" (BobsV35B@aol.com)
18. 07:11 PM - Re: transorbs (Joel Jacobs)
19. 11:08 PM - Wild flights... 22 hr trip in an LSA over the Atlantic... (Jay Hyde)
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Subject: | Re: Autopilots vs. "The Right Stuff" |
>
> http://tinyurl.com/lcuqkc
>
The cheap ones like the above don't work that well (although it will
still make the tail human controllable during helicopter aerobatics).
The quality futaba products aren't that cheap. The difference between
the quality and cheaper products are how much drift in yaw they allow
under normal circumstances and how that effect varies based on input
voltage variance and temperature variance and how well the gyro deals
with vibration. The expensive ones perform better in other ways that
matter in a rc helicopter but aren't needed in a wing leveler
environment (which would be levels of magnitude less demanding).
If i'm not mistaken Futaba actually produces their own sensors which
implies to me that signal conditioning commercial off the shelf
sensors must not be easy in demanding situations.
Then again you talk about gps input so with proper software you could
continually calibrate what signal from the gyro means "zero yaw" (or
any other yaw rate). The thing is if you're going to do that it might
just be as easy to buy a quality gps chipset and calculate for bank
angle based on ground speed and turning radius (like the Garmin 396
and later do on their instrument page). Without the gps input or
alternately a 3-axis compass input it would be difficult to not have
the autopilot (using whatever sensors are in the cheaper rc heli
gyros) continually command a very slow (yet highly annoying) turn.
c'ya,
Michael
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Subject: | Re: Autopilots vs. "The Right Stuff" |
Good Morning Michael,
Great information for an old guy like me that is still struggling with Ohms
Law!
May I interject a few thoughts though?
This new technology is certain to provide us with excellent autopilots and
situational awareness instrumentation. The advancements in technology are
mind boggling. Anything we purchase becomes obsolete before the ink is dry
on the check.
That is all to the good and I love to see it happening.
Back to the world of application.
The first time Wilbur, Orville or Glenn had difficulty establishing their
reference to the natural horizon, folks realized that some instrumentation
would be required to allow safe flight when visibility was reduced.
The principles of the gyroscope were well understood and it was not long
before various adaptations were applied to aircraft control.
At the same time, the Wrights and other pioneers realized that there was
benefit to building aerodynamic stability into their flying machines. As an
aside, the Wrights had initially thought that the machine needed to be built
with almost neutral stability in order for it to be controllable. The
reason they never rebuilt the original Wright Flyer, but went on to another
design is because their flights on December 17, 1903 taught them that the
Flyer was not stable enough for practical flight.
By the end of World War One, the concept of making the airplane dynamically
stable and using a gyroscope to tell the pilot he/she was turning was well
established. Monster ship's gyroscopes were too expensive and too heavy
for practical airborne use, but a simple gyroscope hooked to some sort of an
indicator that could tell the pilot the craft was turning was light weight
and cheap enough that it became common equipment. Most of those units used
a needle of some sort to tell the pilot what was happening. Many of the
ones developed by European interests had the needle hinged at the top. Most
that were developed on our side of the pond had the needle hinged at the
bottom.
By using the Turn needle to keep any turning force to a minimum and by
learning the idiosyncrasies of Magnetic Compass precession during turns, it
became practical to fly in cloud. Not easy, but doable.
By the end of WW I the shape of future instrumentation was quite evident.
They had learned that if you stop the turn, you will survive!
Since coordinated flight was found to be advantageous, a simple
inclinometer was added to the flight panel to display the degree of coordination
being used. By the beginning of WWII, most turn instruments had that ball
included within the same instrument case.
Gyroscopes that showed an artificial horizon were developed, but they
tended to be very heavy, very expensive, very delicate and not at all reliable
if their mechanical limitations were exceeded.
During the late twenties and early thirties, instrument flight became a
practical endeavor. The Turn and Bank was the main thing used to allow the
pilots to perceive a turning moment and the built in stability of the aircraft
was such that it was relatively easy to evaluate the pitch and speed of
the aircraft by the response of the airspeed indicator and the altimeter.
Thus we had Needle, Ball, and Airspeed IFR flight.
By the time WWII came along, the artificial horizons had gotten cheap
enough and light enough such that they were fitted to most airliners and many
larger military aircraft. Sure made for easier and smoother flight
operations.
Notice that, thus far, we were still relying primarily on a human being to
supply the motion need to position the controls?
Efforts had been made to build machinery that would perform that function,
but was not yet well developed.
Since this dissertation is getting way too long for an avionics list, fast
forward to today.
We now have almost unlimited calculating capability and there seems to be
no reason why the human even needs to be involved other than as a mechanism
to monitor what the electrons are doing. Given sufficient computing power,
there is no doubt in my mind that it is relatively easy to make a machine
that has a lower failure rate than do we mere humans.
So, I guess the question is, how much do we want humans to be involved?
Happy Skies,
Old Bob
LL22
Stearman N3977A
In a message dated 7/21/2009 3:28:15 A.M. Central Daylight Time,
mjpereira68@gmail.com writes:
Then again you talk about gps input so with proper software you could
continually calibrate what signal from the gyro means "zero yaw" (or
any other yaw rate). The thing is if you're going to do that it might
just be as easy to buy a quality gps chipset and calculate for bank
angle based on ground speed and turning radius (like the Garmin 396
and later do on their instrument page). Without the gps input or
alternately a 3-axis compass input it would be difficult to not have
the autopilot (using whatever sensors are in the cheaper rc heli
gyros) continually command a very slow (yet highly annoying) turn.
c'ya,
Michael
**************What's for dinner tonight? Find quick and easy dinner ideas
for any occasion.
(http://food.aol.com/dinner-tonight?ncid=emlcntusfood00000009)
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Subject: | Re: Autopilots vs. "The Right Stuff" |
At 03:05 AM 7/21/2009, you wrote:
><mjpereira68@gmail.com>
>
> >
> > http://tinyurl.com/lcuqkc
> >
>
>The cheap ones like the above don't work that well (although it will
>still make the tail human controllable during helicopter aerobatics).
The citation of this particular part was not intended to
suggest suitability to any task, only to illustrate the
advancements in micro-electronics for the sensing of physical
phenomena. Certainly there are moderately priced, solid state
rate sensors that may be better suited to the task of
crafting a flight augmentation system for a manned aircraft.
But even the best sensors have offset gain and temperature
coefficient errors that must be considered as part of the
overall error budget. The neat thing about teaming these devices
with micro-controllers is the ability to compare sensor outputs
with other, more stable data sources and deduce those errors
for the purposes of reducing/eliminating their effects.
For example, we could take the least expensive of
rate sensors combined with a GPS receiver and artfully
crafted software that would allow the autopilot to go through
some gentle maneuvers, compare expected GPS data with real
data and calculate new offset and gain values for the
as-installed rate sensor. Tailoring an autopilot
to a specific airframe and its installation is a tedious
and exacting process. However, for the simple heading-hold
wing leveler, a freshly installed system could be placed in
a temporary calibration mode and flown at altitude while
allowing the autopilot to wiggle the controls and deduce
appropriate gain and offset values for ALL of the as-installed
hardware. Once the calibration sequence is completed, a
switch is moved from the CAL to the FLY position and the
processor stores all the new values for operation.
If the el-cheeso rate sensor exhibits some degree of
long term drift, the CAL process can be repeated at
the owner's convenience to trim up system performance
at any time. Further, cross checking against GPS data,
allows small values of drift to be deduced on-the-fly
and accounted for. FAA rules for software qualification
would make such conveniences very difficult in a TC aircraft.
As I suggested in an earlier post, the availability
and capability of inexpensive GPS engines, micro-controllers
and low-cost rate sensors is head-and-shoulders above
those components which were the best we knew how to do
30 years ago.
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
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Subject: | Re: Autopilots vs. "The Right Stuff" |
At 10:58 PM 7/20/2009, you wrote:
>
>I recall hearing that the solid state sensors (gyros) had a problem
>with drift. Is this still an issue?
You betcha! But it's slow and can be accommodated
in software. See companion posting.
Bob . . .
---------------------------------------
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
---------------------------------------
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Subject: | Re: Air conditioning stuff for sale |
Hi Dean, I'll pass on the R12, apparently, it's pretty difficult to get through
the 49th Parallel Wall and I don't have a use for it right now. Thanks for
thinking of me, anything else you have?
Doug
>>> DEAN PSIROPOULOS <dean.psiropoulos@verizon.net> 07/19/09 9:22 PM >>>
Don't know if any of you are contemplating an air conditioning system in
your airplane or have an old R-12 system in your airplane (or car) that
needs fixing but I may have what you need. Since I no longer own a vehicle
that uses R-12 refrigerant I have seven 12 ounce cans available for sale at
$35 dollars apiece (a repair shop now charges upwards of $100 a pound for
R-12, if they can locate some). I also have an R-12 manifold gauge set
(used to monitor the high and low pressures in an R-12 system while filling)
and a tap for the R-12 cans ($35.00 for both of these). Let me know if you
need any of these or, buy the whole ball of wax for $250.00.
Dean Psiropoulos
RV-6A N197DM
Prop removed for radiographic inspection.
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Subject: | Re: Autopilots vs. "The Right Stuff" |
On Tue, Jul 21, 2009 at 6:21 AM, Robert L. Nuckolls,
III<nuckolls.bob@aeroelectric.com> wrote:
> <nuckolls.bob@aeroelectric.com>
>
> At 03:05 AM 7/21/2009, you wrote:
>>
>> <mjpereira68@gmail.com>
>>
>> >
>> > http://tinyurl.com/lcuqkc
>> >
>>
>> The cheap ones like the above don't work that well (although it will
>> still make the tail human controllable during helicopter aerobatics).
>
> The citation of this particular part was not intended to
> suggest suitability to any task, only to illustrate the
> advancements in micro-electronics for the sensing of physical
> phenomena. Certainly there are moderately priced, solid state
> rate sensors that may be better suited to the task of
> crafting a flight augmentation system for a manned aircraft.
>
> But even the best sensors have offset gain and temperature
> coefficient errors that must be considered as part of the
> overall error budget. The neat thing about teaming these devices
> with micro-controllers is the ability to compare sensor outputs
> with other, more stable data sources and deduce those errors
> for the purposes of reducing/eliminating their effects.
>
> For example, we could take the least expensive of
> rate sensors combined with a GPS receiver and artfully
> crafted software that would allow the autopilot to go through
> some gentle maneuvers, compare expected GPS data with real
> data and calculate new offset and gain values for the
> as-installed rate sensor. Tailoring an autopilot
> to a specific airframe and its installation is a tedious
> and exacting process. However, for the simple heading-hold
> wing leveler, a freshly installed system could be placed in
> a temporary calibration mode and flown at altitude while
> allowing the autopilot to wiggle the controls and deduce
> appropriate gain and offset values for ALL of the as-installed
> hardware. Once the calibration sequence is completed, a
> switch is moved from the CAL to the FLY position and the
> processor stores all the new values for operation.
Oh i agree with everything you've said. I think you'd have to manage
without a specific calibration routine however, it's something that
would have to run constantly (and that's assuming the quality
gyro/rate sensor).
>
> If the el-cheeso rate sensor exhibits some degree of
> long term drift, the CAL process can be repeated at
> the owner's convenience to trim up system performance
> at any time. Further, cross checking against GPS data,
> allows small values of drift to be deduced on-the-fly
> and accounted for. FAA rules for software qualification
> would make such conveniences very difficult in a TC aircraft.
The thing with the cheesy sensors as applied to the rc heli gyros is
the drift varies from minute to minute requiring constant trim
adjustments to the tail channel so it'll sit (relatively) still while
the stick is at neutral. Now, the problem could be more related to
crummy software than the sensor itself. No way to know in this kind of
black box situation what components are generating what percentage of
the total error.
Whatever the case is with the cheesy gyros, futaba has it nailed with
their more expensive stuff. Their tech is probably good enough for
the cockpit (at least in general aviation). The drift errors are
small, that has to make writing the calibration software easier. They
probably aren't crazy enough to license it to that market considering
the market size/liability issues though.
> As I suggested in an earlier post, the availability
> and capability of inexpensive GPS engines, micro-controllers
> and low-cost rate sensors is head-and-shoulders above
> those components which were the best we knew how to do
> 30 years ago.
So i'm curious. I've read a bit about 3-axis electronic compasses
(basically the 3d allows the device to automatically compensate for
magnetic tilt errors). If these devices are accurate enough and update
fast enough, could one of these alone drive a simple wing leveler ?
ie. change in heading divided by time equals rate of turn, etc. Well
actually, I guess it would act nuts if you were operating close enough
to one of the magnetic poles, nevermind. lol.
c'ya,
Michael
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Subject: | Re: Autopilots vs. "The Right Stuff" |
>
>Oh i agree with everything you've said. I think you'd have to manage
>without a specific calibration routine however, it's something that
>would have to run constantly (and that's assuming the quality
>gyro/rate sensor).
Sure, with the GPS engine data we can resolve slow, short term
drifts and compensate on-the-fly. The larger calibration
corrections would probably be a one-time thing that would
wash out initial offset, gains and mechanism transfer
functions.
>The thing with the cheesy sensors as applied to the rc heli gyros is
>the drift varies from minute to minute requiring constant trim
>adjustments to the tail channel so it'll sit (relatively) still while
>the stick is at neutral. Now, the problem could be more related to
>crummy software than the sensor itself. No way to know in this kind of
>black box situation what components are generating what percentage of
>the total error.
We would probably not choose to get THAT cheesy. There's a host
of rate sensors offered by the micro-machined chip manufacturers
with very useable drift characteristics.
>Whatever the case is with the cheesy gyros, futaba has it nailed with
>their more expensive stuff. Their tech is probably good enough for
>the cockpit (at least in general aviation). The drift errors are
>small, that has to make writing the calibration software easier. They
>probably aren't crazy enough to license it to that market considering
>the market size/liability issues though.
Wouldn't seek a "license" . . . there are plenty of
commercial, off-the-shelf devices to choose from that
have no more liability for airplanes falling out of the
sky than do the nail manufacturer's have to shoulder for
houses falling down.
> > As I suggested in an earlier post, the availability
> > and capability of inexpensive GPS engines, micro-controllers
> > and low-cost rate sensors is head-and-shoulders above
> > those components which were the best we knew how to do
> > 30 years ago.
>
>So i'm curious. I've read a bit about 3-axis electronic compasses
>(basically the 3d allows the device to automatically compensate for
>magnetic tilt errors). If these devices are accurate enough and update
>fast enough, could one of these alone drive a simple wing leveler ?
>ie. change in heading divided by time equals rate of turn, etc. Well
>actually, I guess it would act nuts if you were operating close enough
>to one of the magnetic poles, nevermind. lol.
They're interesting devices and we looked at them several
times at the Beech/RAC Targets division. Problem is that
there are 3 conditions of orientation where these devices
fall out of bed. That's when any one of the three axes are
exactly aligned with earth magnetic flux lines. Under that
condition, the other two axes see the same data no matter
how the device is rotated about that axis. While these
may be transient conditions, they offered enough risk to
operation of the fully aerobatic target that we rejected
their incorporation into the product.
It may be that one could use them with more confidence
where the design goal is not to recover from an unusual attitude
but to keep from getting into an unusual attitude.
Bob . . .
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Subject: | Re: Autopilots vs. "The Right Stuff" |
Bob,
Great review......
Dave
----- Original Message -----
From: BobsV35B@aol.com
To: aeroelectric-list@matronics.com
Sent: Tuesday, July 21, 2009 6:12 AM
Subject: Re: AeroElectric-List: Autopilots vs. "The Right Stuff"
Good Morning Michael,
Great information for an old guy like me that is still struggling with
Ohms Law!
May I interject a few thoughts though?
This new technology is certain to provide us with excellent autopilots
and situational awareness instrumentation. The advancements in
technology are mind boggling. Anything we purchase becomes obsolete
before the ink is dry on the check.
That is all to the good and I love to see it happening.
Back to the world of application.
The first time Wilbur, Orville or Glenn had difficulty establishing
their reference to the natural horizon, folks realized that some
instrumentation would be required to allow safe flight when visibility
was reduced.
The principles of the gyroscope were well understood and it was not
long before various adaptations were applied to aircraft control.
At the same time, the Wrights and other pioneers realized that there
was benefit to building aerodynamic stability into their flying
machines. As an aside, the Wrights had initially thought that the
machine needed to be built with almost neutral stability in order for it
to be controllable. The reason they never rebuilt the original Wright
Flyer, but went on to another design is because their flights on
December 17, 1903 taught them that the Flyer was not stable enough for
practical flight.
By the end of World War One, the concept of making the airplane
dynamically stable and using a gyroscope to tell the pilot he/she was
turning was well established. Monster ship's gyroscopes were too
expensive and too heavy for practical airborne use, but a simple
gyroscope hooked to some sort of an indicator that could tell the pilot
the craft was turning was light weight and cheap enough that it became
common equipment. Most of those units used a needle of some sort to
tell the pilot what was happening. Many of the ones developed by
European interests had the needle hinged at the top. Most that were
developed on our side of the pond had the needle hinged at the bottom.
By using the Turn needle to keep any turning force to a minimum and by
learning the idiosyncrasies of Magnetic Compass precession during turns,
it became practical to fly in cloud. Not easy, but doable.
By the end of WW I the shape of future instrumentation was quite
evident.
They had learned that if you stop the turn, you will survive!
Since coordinated flight was found to be advantageous, a simple
inclinometer was added to the flight panel to display the degree of
coordination being used. By the beginning of WWII, most turn instruments
had that ball included within the same instrument case.
Gyroscopes that showed an artificial horizon were developed, but they
tended to be very heavy, very expensive, very delicate and not at all
reliable if their mechanical limitations were exceeded.
During the late twenties and early thirties, instrument flight became
a practical endeavor. The Turn and Bank was the main thing used to allow
the pilots to perceive a turning moment and the built in stability of
the aircraft was such that it was relatively easy to evaluate the pitch
and speed of the aircraft by the response of the airspeed indicator and
the altimeter.
Thus we had Needle, Ball, and Airspeed IFR flight.
By the time WWII came along, the artificial horizons had gotten cheap
enough and light enough such that they were fitted to most airliners and
many larger military aircraft. Sure made for easier and smoother flight
operations.
Notice that, thus far, we were still relying primarily on a human
being to supply the motion need to position the controls?
Efforts had been made to build machinery that would perform that
function, but was not yet well developed.
Since this dissertation is getting way too long for an avionics list,
fast forward to today.
We now have almost unlimited calculating capability and there seems to
be no reason why the human even needs to be involved other than as a
mechanism to monitor what the electrons are doing. Given sufficient
computing power, there is no doubt in my mind that it is relatively easy
to make a machine that has a lower failure rate than do we mere humans.
So, I guess the question is, how much do we want humans to be
involved?
Happy Skies,
Old Bob
LL22
Stearman N3977A
In a message dated 7/21/2009 3:28:15 A.M. Central Daylight Time,
mjpereira68@gmail.com writes:
Then again you talk about gps input so with proper software you
could
continually calibrate what signal from the gyro means "zero yaw" (or
any other yaw rate). The thing is if you're going to do that it
might
just be as easy to buy a quality gps chipset and calculate for bank
angle based on ground speed and turning radius (like the Garmin 396
and later do on their instrument page). Without the gps input or
alternately a 3-axis compass input it would be difficult to not
have
the autopilot (using whatever sensors are in the cheaper rc heli
gyros) continually command a very slow (yet highly annoying) turn.
c'ya,
Michael
-------------------------------------------------------------------------
-----
What's for dinner tonight? Find quick and easy dinner ideas for any
occasion.
Message 9
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Subject: | Re: Autopilots vs. "The Right Stuff" |
Yes, with the wondrous capabilities and reliability of today's computer controlled
machines, be assured that nothing can go wrong...go wrong...go wrong....go........
I seem to recall reading about several accidents caused by the erroneous actions
of computer controlled servo systems; actions that couldn't be detected nor
corrected by the pilots.? Admittedly, these were the result of faulty assumptions
being built into the computer's database by humans.? I guess it comes down
to "who (or what) do you trust?"
Jay
-----Original Message-----
From: David LLoyd <skywagon@charter.net>
Sent: Tue, Jul 21, 2009 10:27 am
Subject: Re: AeroElectric-List: Autopilots vs. "The Right Stuff"
Bob,
?
Great review......
Dave
----- Original Message -----
From:
BobsV35B@aol.com
Sent: Tuesday, July 21, 2009 6:12
AM
Subject: Re: AeroElectric-List:
Autopilots vs. "The Right Stuff"
Good Morning Michael,
?
Great information for an old guy like me that is still struggling with
Ohms Law!
?
May I interject a few thoughts though?
?
This new technology is certain to provide us with excellent autopilots
and situational awareness instrumentation. The advancements in technology are
mind boggling. Anything we purchase becomes obsolete before the ink is dry on
the check.
?
That is all to the good and I love to see it happening.
?
Back to the world of application.
?
The first time Wilbur, Orville or Glenn had difficulty establishing their
reference to the natural horizon, folks realized that some instrumentation
would be required to allow safe flight when visibility was reduced.
?
The principles of the gyroscope were well understood and it was not long
before various adaptations were applied to aircraft control.
?
At the same time, the Wrights and other pioneers realized that there was
benefit to building aerodynamic stability into their flying machines. As an
aside, the Wrights had initially thought that the machine needed to be built
with almost neutral stability in order for it to be controllable. The reason
they never rebuilt the original Wright Flyer, but went on to another design is
because their flights on December 17, 1903 taught them that the Flyer was not
stable enough for practical flight.
?
By the end of World War One, the concept of making the airplane
dynamically stable and using a gyroscope to tell the pilot he/she was turning
was well established. Monster ship's gyroscopes were too expensive and too
heavy for practical airborne use, but a simple gyroscope hooked to some sort
of an indicator that could tell the pilot the craft was turning was light
weight and cheap enough that it became common equipment.? Most of those
units used a needle of some sort to tell the pilot what was happening. Many of
the ones developed by European interests had the needle hinged at the top.
Most that were developed on our side of the pond had the needle hinged at the
bottom.
?
By using the Turn needle to keep any turning force to a minimum and by
learning the idiosyncrasies of Magnetic Compass precession during turns, it
became practical to fly in cloud. Not easy, but doable.
?
By the end of? WW I the shape of future instrumentation was quite
evident.
?
They had learned that if you stop the turn, you will survive!
?
Since coordinated flight was found to be advantageous, a simple
inclinometer was added to the flight panel to display the degree of
coordination being used. By the beginning of WWII, most turn instruments had
that ball included within the same instrument case.
?
Gyroscopes that showed an artificial horizon were developed, but they
tended to be very heavy, very expensive, very delicate and not at all reliable
if their mechanical limitations were exceeded.
?
During the late twenties and early thirties, instrument flight became a
practical endeavor. The Turn and Bank was the main thing used to allow the
pilots to perceive a turning moment and the built in stability of the aircraft
was such that it was relatively easy to evaluate the pitch and speed of the
aircraft by the response of the airspeed indicator and the altimeter.
?
Thus?we had Needle, Ball, and Airspeed IFR flight.
?
By the time WWII came along, the artificial horizons had gotten cheap
enough and light enough such that they were fitted to most airliners and many
larger military aircraft. Sure made for easier and smoother flight
operations.
?
Notice that, thus far, we were still relying primarily on a human being
to supply the motion need to position the controls?
?
Efforts had been made to build machinery that would perform that
function, but was not yet well developed.
?
Since this dissertation is getting way too long for an avionics list,
fast forward to today.
?
We now have almost unlimited calculating capability and there seems to be
no reason why the human even needs to be involved other than as
a?mechanism to monitor what the electrons are doing. Given sufficient
computing power, there is no doubt in my mind that it is relatively easy to
make a machine that has a lower failure rate than do we mere humans.
?
So, I guess the question is, how much do we want humans to be
involved?
?
Happy Skies,
?
Old Bob
LL22
Stearman N3977A
?
In a message dated 7/21/2009 3:28:15 A.M. Central Daylight Time,
mjpereira68@gmail.com writes:
Then again you talk about gps input so with proper software
you could
continually calibrate what signal from the gyro means "zero
yaw" (or
any other yaw rate).? The thing is if you're going to do
that it might
just be as easy to buy a quality gps chipset and calculate
for bank
angle based on ground speed and turning radius (like the Garmin
396
and later do on their instrument page).? Without the gps input
or
alternately a? 3-axis compass input it would be difficult to not
have
the autopilot (using whatever sensors are in the cheaper rc
heli
gyros) continually command a very slow (yet highly annoying)
turn.
c'ya,
Michael
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Subject: | Wild flights... 22 hr trip in an LSA over the Atlantic... |
Hey there all,
I posted something similar to what I will write now but it does not seem to
have come through. Two mates of mine will attempt (and hopefully complete)
a flight across the Atlantic, from Conakry, Guinea to Belem, Brazil tomorrow
evening. They are flying an aircraft called the 'Sling' that they designed
and built here in South Africa; to be sold as a light sport kit. The
aircraft is a low wing 2 seater with a 912 Rotax engine and is specially
modified so that the whole leading edge of each wing is a fuel tank (divided
into 6 tanks), carrying 450 litres of fuel. Tomorrow evening their flight
will use 440 litres.. Its going to be a narrow thing.
The aircraft has a modified Z-16 diagram that I used from Bob's (thank you!)
lists/diagrams. In the aircraft there are 2 MGL Voyagers, a stormscope,
transponder, Garmin SL30 Nav/ Comm radio, auto pilots, and bits and pieces
including a satellite linked GPS tracker so that we can follow their
progress. This last Saturday they took off from near Johannesburg here in
South Africa and flew non-stop for 20 hours to reach Sao Tome off the west
African coast, just south of Nigeria. I was with them when James, one of
the pilots, filed an unbelievable flight plan for an LSA aircraft. He had
to repeat and confirm the distances and aircraft type several times- and
explain this to the disbelieving official at the other end.
If you're curious and would like to see more have a look at
http://www.airplanefactory.co.za/world/default.asp
You will be able to track their flight across the Atlantic tomorrow if all
goes well, and for those of you going to Oshkosh, they'll be there.
Bob, I've read your arguments and as an electrical engineer they made a lot
of sense; I used your suggestions and designs in this aircraft and so far it
has worked well and I am sure that it will continue to do so. Here's hoping
that my mates make it across the pond!
Jay from South Africa
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Subject: | Re: Electrical stuff for sale. |
Hi Dean,
I am wondering if the Rocky Mountain Instrument - Micro Encoder (Unassembled Kit),
fits std 3 1/8 inch instrument hole, displays airspeed, altitude, VSI, OAT,
Altitude alerting, misc warnings. Half the price of new at $450.00 still available?
Is it the low speed or standard speed microencoder? I am interested
in buying this from you. Thank you, Aaron.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=254201#254201
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Subject: | Re: The weak link |
On Mon, Jul 20, 2009 at 6:25 AM, Joe<fran5sew@banyanol.com> wrote:
> Bob Nuckolls said, "Perhaps dual wing levelers are in order? I'd bet that a
> BIG
> chunk of the accidents due to poor pilot visibility and/or
> workload distractions for single-pilot IFR would have been
> averted (if) electrons had the stick. I'll suggest that most
> IFR capable airframes would be better outfitted for ventures
> into poor visibility if there were NO displays on the panel
> and dual, heading-slaved wing levelers installed. The wing
> levelers are probably lighter and more reliable than a suite
> of panel mounted gyros and more capable than pilot's trying
> to manage an airplane . . . .."
>
> I agree wholeheartedly. Flying IFR, if we can trust our lives to
> electronics to take information from sensors and display that information,
> then why can't we trust electronics to actually operate the controls? The
> human being is the weak link in the system. Have you ever noticed the
> control movements when the autopilot is on, compared to when a human is in
> control? Some planes have dual EFISs. I suggest that it would be better to
> have dual autopilots with dual servos. The recreational IFR pilot is better
> off monitoring the system as a whole, watching for component failure, making
> sure that the altitude and heading are correct, handling radio
> communications, looking for traffic, and etc.
> Joe Gores
Joe,
Having software manage your flight controls doesn't eliminate the
human "weak link" it just moves it from the pilot (who's own butt is
on the line) and transfers it to computer programmers, the vast
majority of which only understand a small part of the total program on
large projects (which is unavoidable). They have the privilege of not
being in the aircraft when their products fail (unless they're
working for a major aircraft manufacturer and suffer an incredible
case being in the wrong place at the wrong time).
Don't cast me as a luddite, I have a ton of IT experience. And
honestly all that experience makes me appreciate the concept of having
a hunk of spinning iron as a backup. In fact, since efis is dependant
on electricity, It'd be nice if that spinning gyro was based on vacuum
(or an electrically driven one with it's own internal battery that
*only* drives the motor).
c'ya,
Michael
>
>
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Howdy folks,
In my work we use 30v transorbs similar the ones that have been discussed on
this list for years. We use them to limit relay contact arcing when
switching inductive loads such as mag locks and electric strikes. We have
hundreds in the field and until yesterday I would have said they never go
bad - but yesterday I had a service call and sure enough a transorb had
shorted. In our applications the coil currents range from 125ma to maybe an
amp or so. I don't know why it failed, maybe a manufacturing defect, but
the point becomes that they CAN fail.
So I'm thinking, if I have one of these things across the coil on my master
contactor and it shorts - bad things happen. Not only would I loose
electric power but the un-fused master switch wiring would be overloaded.
I'm thinking maybe a 30v transorb across the master switch - not the
contactor coil may be a better choice if you are going to use them at all.
It would still protect the switch, it would still allow about 15v reverse
voltage to collapse the field in the coil (12v system - use a 45v transorb
in a 24v system) and in a failure mode you would just be unable to shut off
the power.
Anyway, I just wanted to bring attention to an admittedly remote failure
mode and a possible re-configuration that would have a much more favorable
result if a failure did occur.
Joel
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Subject: | Re: The weak link |
> <mjpereira68@gmail.com>
>
snip
>> communications, looking for traffic, and etc.
>> Joe Gores
>
> Joe,
>
> Having software manage your flight controls doesn't eliminate the
> human "weak link" it just moves it from the pilot (who's own butt is
> on the line) and transfers it to computer programmers, the vast
> majority of which only understand a small part of the total program on
> large projects (which is unavoidable). They have the privilege of not
> being in the aircraft when their products fail (unless they're
> working for a major aircraft manufacturer and suffer an incredible
> case being in the wrong place at the wrong time).
>
> Don't cast me as a luddite, I have a ton of IT experience. And
> honestly all that experience makes me appreciate the concept of having
> a hunk of spinning iron as a backup. In fact, since efis is dependant
> on electricity, It'd be nice if that spinning gyro was based on vacuum
> (or an electrically driven one with it's own internal battery that
> *only* drives the motor).
>
> c'ya,
> Michael
>
One benefit the computer programmer has is the opportunity to ponder bad
things happening while sitting at a desk (on the ground), drinking a
favored beverage. On the other hand, the pilot gets to ponder these bad
things while riding through said bad things (which are often quite
distracting). Sometimes the pilot doesn't make the right decision and
doesn't get to take another shot at it. The computer programmer can (with
the help of peers) consider all sorts of malfunctions.
One other thought.. The act of using GPS data to correct for roll/yaw
gyro drift is a far cry (much simpler task) from the tasks currently being
accomplished by the current crop of EFISs. Simpler tasks mean simpler
code, and a much easier device to debug. What amounts to be a single axis
autopilot could be done in very few lines of code.
Matt-
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Interesting.
I could imagine that Bob might like to look at the shorted device - if
it's still around.
I wonder what short circuit current such a transorb might support before
itself becoming a fuse (going open circuit).. If the switch and wiring
can handle it, this may not be a terribly serious issue. A bit smokey
perhaps...
Matt-
> Howdy folks,
> In my work we use 30v transorbs similar the ones that have been discussed
> on
> this list for years. We use them to limit relay contact arcing when
> switching inductive loads such as mag locks and electric strikes. We have
> hundreds in the field and until yesterday I would have said they never go
> bad - but yesterday I had a service call and sure enough a transorb had
> shorted. In our applications the coil currents range from 125ma to maybe
> an
> amp or so. I don't know why it failed, maybe a manufacturing defect, but
> the point becomes that they CAN fail.
>
> So I'm thinking, if I have one of these things across the coil on my
> master
> contactor and it shorts - bad things happen. Not only would I loose
> electric power but the un-fused master switch wiring would be overloaded.
> I'm thinking maybe a 30v transorb across the master switch - not the
> contactor coil may be a better choice if you are going to use them at all.
> It would still protect the switch, it would still allow about 15v reverse
> voltage to collapse the field in the coil (12v system - use a 45v transorb
> in a 24v system) and in a failure mode you would just be unable to shut
> off
> the power.
>
> Anyway, I just wanted to bring attention to an admittedly remote failure
> mode and a possible re-configuration that would have a much more favorable
> result if a failure did occur.
>
> Joel
>
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Subject: | Re: Autopilots vs. "The Right Stuff" |
BobsV35B@aol.com wrote:
> Good Morning Michael,
>
> Great information for an old guy like me that is still struggling with Ohms
> Law!
>
> May I interject a few thoughts though?
>
> This new technology is certain to provide us with excellent autopilots and
> situational awareness instrumentation. The advancements in technology are
> mind boggling. Anything we purchase becomes obsolete before the ink is dry
> on the check.
>
>
You still write checks? Don't you know that technology have made them
obsolete? 8*)
<snip>
>
> So, I guess the question is, how much do we want humans to be involved?
>
I didn't get a pilot's license so that a machine could fly me around. 8*)
--
http://www.ernest.isa-geek.org
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Subject: | Re: Autopilots vs. "The Right Stuff" |
Good Evening Ernest,
May I take it from that statement that you prefer a Boeing over an Airbus?
I repeat: The question is, how much do we want humans to be involved?
Happy Skies,
Old Bob
In a message dated 7/21/2009 8:16:03 P.M. Central Daylight Time,
echristley@nc.rr.com writes:
I didn't get a pilot's license so that a machine could fly me around. 8*)
**************What's for dinner tonight? Find quick and easy dinner ideas
for any occasion.
(http://food.aol.com/dinner-tonight?ncid=emlcntusfood00000009)
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Yes I still have it and I'd be happy to send it to Bob if he wants to take a
look. It's in heat shrink with lead wires sticking out. I haven't molested
it yet - just checked it with a meter. A transorb is basicaly two zeners
back to back and one in this is shorted. It measures a standard diode drop
one way and open the other.
Joel
On Tue, Jul 21, 2009 at 8:39 PM, Matt Prather <mprather@spro.net> wrote:
> >
>
> Interesting.
>
> I could imagine that Bob might like to look at the shorted device - if
> it's still around.
>
> I wonder what short circuit current such a transorb might support before
> itself becoming a fuse (going open circuit).. If the switch and wiring
> can handle it, this may not be a terribly serious issue. A bit smokey
> perhaps...
>
>
> Matt-
>
> > Howdy folks,
> > In my work we use 30v transorbs similar the ones that have been discussed
> > on
> > this list for years. We use them to limit relay contact arcing when
> > switching inductive loads such as mag locks and electric strikes. We
> have
> > hundreds in the field and until yesterday I would have said they never go
> > bad - but yesterday I had a service call and sure enough a transorb had
> > shorted. In our applications the coil currents range from 125ma to maybe
> > an
> > amp or so. I don't know why it failed, maybe a manufacturing defect, but
> > the point becomes that they CAN fail.
> >
> > So I'm thinking, if I have one of these things across the coil on my
> > master
> > contactor and it shorts - bad things happen. Not only would I loose
> > electric power but the un-fused master switch wiring would be overloaded.
> > I'm thinking maybe a 30v transorb across the master switch - not the
> > contactor coil may be a better choice if you are going to use them at
> all.
> > It would still protect the switch, it would still allow about 15v reverse
> > voltage to collapse the field in the coil (12v system - use a 45v
> transorb
> > in a 24v system) and in a failure mode you would just be unable to shut
> > off
> > the power.
> >
> > Anyway, I just wanted to bring attention to an admittedly remote failure
> > mode and a possible re-configuration that would have a much more
> favorable
> > result if a failure did occur.
> >
> > Joel
> >
>
>
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Subject: | Wild flights... 22 hr trip in an LSA over the Atlantic... |
Hey there all,
I posted something similar to what I will write now but it does not seem to
have come through. Two mates of mine will attempt (and hopefully complete)
a flight across the Atlantic, from Conakry, Guinea to Belem, Brazil this
evening. They are flying an aircraft called the Sling that they designed
and built here in South Africa; to be sold as a light sport kit. The
aircraft is a low wing 2 seater with a 912 Rotax engine and is specially
modified so that the whole leading edge of each wing is a fuel tank (divided
into 6 tanks), carrying 450 litres of fuel. This evening their flight will
use 440 litres. Its going to be a narrow thing.
The aircraft has a modified Z-16 diagram that I used from Bobs (thank you!)
lists/diagrams. In the aircraft there are 2 MGL Voyagers, a stormscope,
transponder, Garmin SL30 Nav/ Comm radio, auto pilots, and bits and pieces
including a satellite linked GPS tracker so that we can follow their
progress. This last Saturday they took off from near Johannesburg here in
South Africa and flew non-stop for 20 hours to reach Sao Tome off the west
African coast, just south of Nigeria. I was with them when James, one of
the pilots, filed an unbelievable flight plan for an LSA aircraft. He had
to repeat and confirm the distances and aircraft type several times- and
explain this to the disbelieving official at the other end.
If youre curious and would like to see more have a look at
http://www.airplanefactory.co.za/world/default.asp
You will be able to track their flight across the Atlantic tomorrow if all
goes well, and for those of you going to Oshkosh, theyll be there.
Bob, Ive read your arguments and as an electrical engineer they made a lot
of sense; I used your suggestions and designs in this aircraft and so far it
has worked well and I am sure that it will continue to do so. Heres hoping
that my mates make it across the pond!
Jay from South Africa
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