Today's Message Index:
----------------------
1. 12:39 AM - Re: Any thoughts on FLAPS? (nico css)
2. 05:33 AM - Re: Another derelect (BobsV35B@aol.com)
3. 09:18 AM - Re: Any thoughts on FLAPS? (Donnie Rose)
4. 09:44 AM - Re: Any thoughts on FLAPS? (Bill Bow)
5. 11:08 AM - Re: Diesel Daydreams (John Vormbaum)
6. 11:45 AM - Re: Any thoughts on FLAPS? (BillLeff1@aol.com)
7. 12:44 PM - Re: Re: Diesel Daydreams (BobsV35B@aol.com)
8. 01:38 PM - Re: Re: Diesel Daydreams (John Vormbaum)
9. 03:03 PM - Two New Email Lists at Matronics and Wiki Reminder! (Matt Dralle)
10. 05:13 PM - Re: Re: Diesel Daydreams (nico css)
11. 10:52 PM - Re: Any thoughts on FLAPS? (CloudCraft@aol.com)
Message 1
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| Subject: | Any thoughts on FLAPS? |
--> Commander-List message posted by: "nico css" <nico@cybersuperstore.com>
I don't even take off a Cessna 150 without flaps set to at least 10.
Although the Commanders don't have Fowler flaps, it still increases lift
more than it increases drag at 10 deg. It just makes sense to increase lift
on take-off. When flap settings will cause the plane to lift off before VMC,
then I will take off without flaps, but Commanders will run off the end of
the world if the pilot doesn't positively rotate. Moreover, if an engine
fails immediately after take-off (who's paying attention to balanced
fields?), I kinda like the spread between stall speed and airspeed with 10
deg flaps.
It's my 2c worth.
Nico
-----Original Message-----
From: owner-commander-list-server@matronics.com
[mailto:owner-commander-list-server@matronics.com] On Behalf Of Robert S.
Randazzo
Sent: Sunday, May 28, 2006 11:53 PM
Subject: Commander-List: Any thoughts on FLAPS?
--> Commander-List message posted by: "Robert S. Randazzo"
<rsrandazzo@precisionmanuals.com>
Commanders-
I'm still in the process of compiling me general fund of knowledge- and
thought you guys might be able to help with this mystery....
The Pilots Operating Handbook for the Commander 685 references conducting
all takeoffs with the flaps UP.
When I was checked out in N414C at purchase, the check pilot said that he
conducts all of his takeoffs at flaps 10.
I've used his advice- although for giggles I conducted one takeoff without
them just to feel the difference.
I found that performance (we are at 5200' MSL) was better with the flaps at
10, so this would seem to be my preference.
I have not scientifically conducted any takeoff distance/climb performance
measurements yet, obviously.
Anyone have any hard-fast logic on this?
Robert Randazzo
Message 2
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| Subject: | Re: Another derelect |
--> Commander-List message posted by: BobsV35B@aol.com
Good Morning John,
The engine does sound very interesting.
I wouldn't count on getting a gross weight approval. The problem is more one
of meeting the noise requirements than the performance requirements.
The increase in engine weight could be a problem due to the potential
structural requirements to carry the engine (Mounts and attach points may need
a
beef up.)
Assuming that the Commander structure IS strong enough to meet the
requirements as is, the airplane will have to demonstrate that it can meet the
new
Part 36 (I think!) criteria to get a gross weight increase. One way that has
been accomplished by other converters has been to show that the new power plant
allowed a higher rate of climb which allowed the airplane to pass over the
recording devices high enough to meet the new specifications.
I doubt if the increase in power will be enough to meet that criteria.
However, if the engine can meet the published fuel consumption figure, it
should be able to carry a higher payload on any flight longer than a couple of
hours by burning less fuel at any specified air speed that is above best L/D.
I don't know if the market is large enough to justify the difficulties of
getting an approval past the Friendly Aviation Attack dogs, but it does sound
like an excellent way to go.
I certainly wish them well!
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Air Park LL22
Downers Grove, IL 60516
630 985-8503
In a message dated 5/29/2006 1:37:26 A.M. Central Standard Time,
john@vormbaum.com writes:
Don't quote me, but I seem to recall that the kit will add about 60lbs. per
side. That may not be prohibitive, considering the probable gross weight
increase we'd get from the addition of extra horsepower. I'll bet that
if/when it's approved as a replacement for the direct-drive Commanders,
they'll specify 300 or 320 hp per engine vs. the original 290.
Message 3
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| Subject: | Re: Any thoughts on FLAPS? |
--> Commander-List message posted by: Donnie Rose <aquadiver99@yahoo.com>
Hey Robert, I own a 500B but the differences are VERY
little. My POH says the same. What I have found to be
the most beneficial is flaps up or 10, no great diff,
but as soon as you start rolling, maintain back
pressure on the yoke so at 85 mph or so you are
airborne.
This technique reduces your ground roll and wear on
the nose wheel. Otherwise, you will remain on the
ground indefinitely until you finally pull back and
shoot up in the air.
--- "Robert S. Randazzo"
<rsrandazzo@precisionmanuals.com> wrote:
> --> Commander-List message posted by: "Robert S.
> Randazzo" <rsrandazzo@precisionmanuals.com>
>
> Commanders-
>
> I'm still in the process of compiling me general
> fund of knowledge- and
> thought you guys might be able to help with this
> mystery....
>
> The Pilots Operating Handbook for the Commander 685
> references conducting
> all takeoffs with the flaps UP.
>
> When I was checked out in N414C at purchase, the
> check pilot said that he
> conducts all of his takeoffs at flaps 10.
>
> I've used his advice- although for giggles I
> conducted one takeoff without
> them just to feel the difference.
>
> I found that performance (we are at 5200' MSL) was
> better with the flaps at
> 10, so this would seem to be my preference.
>
> I have not scientifically conducted any takeoff
> distance/climb performance
> measurements yet, obviously.
>
> Anyone have any hard-fast logic on this?
>
> Robert Randazzo
>
>
>
>
>
> browse
> Subscriptions page,
> FAQ,
> http://www.matronics.com/Navigator?Commander-List
>
>
> Admin.
>
>
>
>
>
>
>
>
>
>
>
Donnie Rose
205/492-8444
__________________________________________________
Message 4
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| Subject: | Any thoughts on FLAPS? |
--> Commander-List message posted by: "Bill Bow" <bowing74@earthlink.net>
I like "shooting up in the air".
bilbo
-----Original Message-----
From: owner-commander-list-server@matronics.com
[mailto:owner-commander-list-server@matronics.com] On Behalf Of Donnie Rose
Sent: Monday, May 29, 2006 12:18 PM
Subject: Re: Commander-List: Any thoughts on FLAPS?
--> Commander-List message posted by: Donnie Rose <aquadiver99@yahoo.com>
Hey Robert, I own a 500B but the differences are VERY
little. My POH says the same. What I have found to be
the most beneficial is flaps up or 10, no great diff,
but as soon as you start rolling, maintain back
pressure on the yoke so at 85 mph or so you are
airborne.
This technique reduces your ground roll and wear on
the nose wheel. Otherwise, you will remain on the
ground indefinitely until you finally pull back and
shoot up in the air.
--- "Robert S. Randazzo"
<rsrandazzo@precisionmanuals.com> wrote:
> --> Commander-List message posted by: "Robert S.
> Randazzo" <rsrandazzo@precisionmanuals.com>
>
> Commanders-
>
> I'm still in the process of compiling me general
> fund of knowledge- and
> thought you guys might be able to help with this
> mystery....
>
> The Pilots Operating Handbook for the Commander 685
> references conducting
> all takeoffs with the flaps UP.
>
> When I was checked out in N414C at purchase, the
> check pilot said that he
> conducts all of his takeoffs at flaps 10.
>
> I've used his advice- although for giggles I
> conducted one takeoff without
> them just to feel the difference.
>
> I found that performance (we are at 5200' MSL) was
> better with the flaps at
> 10, so this would seem to be my preference.
>
> I have not scientifically conducted any takeoff
> distance/climb performance
> measurements yet, obviously.
>
> Anyone have any hard-fast logic on this?
>
> Robert Randazzo
>
>
>
>
>
> browse
> Subscriptions page,
> FAQ,
> http://www.matronics.com/Navigator?Commander-List
>
>
> Admin.
>
>
>
>
>
>
>
>
>
>
>
Donnie Rose
205/492-8444
__________________________________________________
Message 5
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| Subject: | Re: Diesel Daydreams |
--> Commander-List message posted by: "John Vormbaum" <john@vormbaum.com>
Hi Bob,
Food for thought...
Merlyn products has a pair of approved conversions to go to a single-turbo
version of the IO-540 Wide Deck engine. BOTH installs result in a gross
weight increase. The kit adds weight, but less than 150 lbs. total (I think)
and the GW increase is on the order of 400 lbs. The engines are rated at
320hp for the low-compression engine and 300hp for the high-compression
conversion (the 300hp turbonormalized conversion adds less weight and gets a
more modest 250lb. increase). Granted, it's still an avgas engine, still a
Lycoming, and still 540ci.....but it is new, it does add HP, and you do get
a GW increase. And it's still Commander Loud.
1) How might the Merlyn conversion be OK with the FAA, but the Centurion
engine wouldn't?
2) The fuel consumption is greater on the Merlyn increase...wouldn't it be
easier to plead your case for a conversion with a lower SFC?
3) The diesel props turn considerably slower than the avgas props (2000-2100
vs. 2575 I believe), which should make LESS noise, right?
4) Centurion has retrofitted a Duke with the 4.0 engine, and that's working
out fine, but the diesels at 606 lbs. (with all accessories) weigh less than
an IO-541. It's still a lot heavier than an IO-540....so I think a
break-even GW would be a nice target, maybe. See the Duke at
http://www.dukeb60.de/ under "news"
5) The Duke stats list the noise level as lower than they Lyc at 78db(A).
This sounds pretty good to me (ewww...a pun).
It sounds like the biggest sticking point might be the engine mounts &
airframe attach points, although I'm pretty optimistic about the strength of
the Commander airframe.
The death knell might be the price. The Duke guy paid EUR 175,000 PER SIDE,
which today is about $223,000 per side. For that price, I could just upgrade
to a 690A.
I just received this from John Towner (he can't post to the list for some
funky technical reason):
I read your message on the chat page about diesel engines. Two years ago we
investigated the diesel for the Aero Commander. I think it would be a great
mod but at the time the engine we looked at weighed about 600 lbs and that
would cut down our usefuel load by about 400 lbs. The other thing I have
learned over the years with the 690 and Learjet flying, unless you can get
above 18,000 extra HP does really not make that much difference in TAS
overall.
I replied to him to ask if he was looking at the Thielert/Centurion
conversion or if there are other players out there.
Cheers,
/John
----- Original Message -----
From: <BobsV35B@aol.com>
Sent: Monday, May 29, 2006 5:32 AM
Subject: Re: Commander-List: Another derelect
> --> Commander-List message posted by: BobsV35B@aol.com
>
>
> Good Morning John,
>
> The engine does sound very interesting.
>
> I wouldn't count on getting a gross weight approval. The problem is more
> one
> of meeting the noise requirements than the performance requirements.
>
> The increase in engine weight could be a problem due to the potential
> structural requirements to carry the engine (Mounts and attach points may
> need a
> beef up.)
>
> Assuming that the Commander structure IS strong enough to meet the
> requirements as is, the airplane will have to demonstrate that it can meet
> the new
> Part 36 (I think!) criteria to get a gross weight increase. One way that
> has
> been accomplished by other converters has been to show that the new power
> plant
> allowed a higher rate of climb which allowed the airplane to pass over the
> recording devices high enough to meet the new specifications.
>
> I doubt if the increase in power will be enough to meet that criteria.
>
> However, if the engine can meet the published fuel consumption figure, it
> should be able to carry a higher payload on any flight longer than a
> couple of
> hours by burning less fuel at any specified air speed that is above best
> L/D.
>
> I don't know if the market is large enough to justify the difficulties of
> getting an approval past the Friendly Aviation Attack dogs, but it does
> sound
> like an excellent way to go.
>
> I certainly wish them well!
>
> Happy Skies,
>
> Old Bob
> AKA
> Bob Siegfried
> Ancient Aviator
> Stearman N3977A
> Brookeridge Air Park LL22
> Downers Grove, IL 60516
> 630 985-8503
>
>
> In a message dated 5/29/2006 1:37:26 A.M. Central Standard Time,
> john@vormbaum.com writes:
>
> Don't quote me, but I seem to recall that the kit will add about 60lbs.
> per
> side. That may not be prohibitive, considering the probable gross weight
> increase we'd get from the addition of extra horsepower. I'll bet that
> if/when it's approved as a replacement for the direct-drive Commanders,
> they'll specify 300 or 320 hp per engine vs. the original 290.
>
>
> __________ NOD32 1.1564 (20060529) Information __________
>
> This message was checked by NOD32 antivirus system.
> http://www.eset.com
>
>
> __________ NOD32 1.1564 (20060529) Information __________
>
> This message was checked by NOD32 antivirus system.
> http://www.eset.com
>
>
Message 6
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| Subject: | Re: Any thoughts on FLAPS? |
--> Commander-List message posted by: BillLeff1@aol.com
That is true. The aircraft performs better as far as getting off the ground
with 1/4 flaps but it degrades single engine performance. Just be careful and
get those flaps up as soon as you get the gear up.
Bill Leff
Message 7
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| Subject: | Re: Diesel Daydreams |
--> Commander-List message posted by: BobsV35B@aol.com
Good Afternoon John,
My totally non fact based comments inserted as appropriate!
In a message dated 5/29/2006 1:09:33 P.M. Central Standard Time,
john@vormbaum.com writes:
1) How might the Merlyn conversion be OK with the FAA, but the Centurion
engine wouldn't?
OB --It All Depends!
If the Merlyn Conversion was approved before the Part 36 standards were
written, it would still be OK. Or maybe it does meet the Part 36 criteria!
2) The fuel consumption is greater on the Merlyn increase...wouldn't it be
easier to plead your case for a conversion with a lower SFC?
OB ---Fuel consumption and efficiency are not subject to FAA approval so it
would have no bearing at all on any approval. However, I agree that the lower
burn and greater efficiency would be a BIG selling point to the users.
3) The diesel props turn considerably slower than the avgas props (2000-2100
vs. 2575 I believe), which should make LESS noise, right?
OB --- Good point.
Actually, if there is no application for a gross weight increase, I don't
think they have to meet the Part 36 criteria, but I am not sure of that.
In any case, quiet is good!
4) Centurion has retrofitted a Duke with the 4.0 engine, and that's working
out fine, but the diesels at 606 lbs. (with all accessories) weigh less than
an IO-541. It's still a lot heavier than an IO-540....so I think a
break-even GW would be a nice target, maybe. See the Duke at
http://www.dukeb60.de/ under "news"
OB --- Sounds good to me.
5) The Duke stats list the noise level as lower than they Lyc at 78db(A).
This sounds pretty good to me (ewww...a pun).
OB --- That's even better.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Air Park LL22
Downers Grove, IL 60516
630 985-8503
Message 8
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| Subject: | Re: Diesel Daydreams |
--> Commander-List message posted by: "John Vormbaum" <john@vormbaum.com>
Hi Bob,
I'm not familiar with Part 36 noise standards...I guess I should read up on
my FARs. Thanks for the comments. I'd love to see a wealthy, intrepid
Commander pilot (is that an oxymoron?) take the plunge and try the diesels.
Personally I think it'll be a while before the costs & benefits balance each
other. In the meantime I'll continue flying my avgas-powered 500B until a
sweet deal on a 690-series airplane catches my attention.
/John
----- Original Message -----
From: <BobsV35B@aol.com>
Sent: Monday, May 29, 2006 12:43 PM
Subject: Re: Commander-List: Re: Diesel Daydreams
> --> Commander-List message posted by: BobsV35B@aol.com
>
>
> Good Afternoon John,
>
> My totally non fact based comments inserted as appropriate!
>
> In a message dated 5/29/2006 1:09:33 P.M. Central Standard Time,
> john@vormbaum.com writes:
>
> 1) How might the Merlyn conversion be OK with the FAA, but the Centurion
> engine wouldn't?
>
>
> OB --It All Depends!
>
> If the Merlyn Conversion was approved before the Part 36 standards were
> written, it would still be OK. Or maybe it does meet the Part 36
> criteria!
>
>
> 2) The fuel consumption is greater on the Merlyn increase...wouldn't it
> be
> easier to plead your case for a conversion with a lower SFC?
>
> OB ---Fuel consumption and efficiency are not subject to FAA approval so
> it
> would have no bearing at all on any approval. However, I agree that the
> lower
> burn and greater efficiency would be a BIG selling point to the users.
>
>
> 3) The diesel props turn considerably slower than the avgas props
> (2000-2100
> vs. 2575 I believe), which should make LESS noise, right?
>
> OB --- Good point.
>
> Actually, if there is no application for a gross weight increase, I don't
> think they have to meet the Part 36 criteria, but I am not sure of that.
>
> In any case, quiet is good!
>
> 4) Centurion has retrofitted a Duke with the 4.0 engine, and that's
> working
> out fine, but the diesels at 606 lbs. (with all accessories) weigh less
> than
> an IO-541. It's still a lot heavier than an IO-540....so I think a
> break-even GW would be a nice target, maybe. See the Duke at
> http://www.dukeb60.de/ under "news"
>
> OB --- Sounds good to me.
>
> 5) The Duke stats list the noise level as lower than they Lyc at 78db(A).
> This sounds pretty good to me (ewww...a pun).
>
> OB --- That's even better.
>
>
> Happy Skies,
>
> Old Bob
> AKA
> Bob Siegfried
> Ancient Aviator
> Stearman N3977A
> Brookeridge Air Park LL22
> Downers Grove, IL 60516
> 630 985-8503
>
>
> __________ NOD32 1.1564 (20060529) Information __________
>
> This message was checked by NOD32 antivirus system.
> http://www.eset.com
>
>
> __________ NOD32 1.1564 (20060529) Information __________
>
> This message was checked by NOD32 antivirus system.
> http://www.eset.com
>
>
Message 9
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| Subject: | Two New Email Lists at Matronics and Wiki Reminder! |
--> Commander-List message posted by: Matt Dralle <dralle@matronics.com>
Dear Listers,
I have added two new email Lists to the Matronics Line up today. These include
a Continental engine List and a Lightning aircraft List:
===========
continental-list@matronics.com
http://www.matronics.com/Navigator?Continental-List
Everything related to the Continental aircraft engine. Sky's the limit on discussions
here.
===========
===========
lightning-list@matronics.com
http://www.matronics.com/Navigator?Lightning-List
This is an exciting new design from Arion Aircraft LLC in Shelbyville Tennessee. Pete Krotje has a very nice web site on the aircraft that can be found here: http://www.arionaircraft.com/
===========
Also, if you haven't checked out the new Matronics Aircraft Wiki, swing by and
have a look. Remember, a Wiki is only as good as the content that the members
put into it. Have a look over some of the sections, and if you've got some interesting
or useful, please add it to the Wiki! Its all about YOU! :-) The
URL for the Matronics Wiki is:
http://wiki.matronics.com
Best regards,
Matt Dralle
Matronics Email List Administrator
Message 10
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| Subject: | Re: Diesel Daydreams |
--> Commander-List message posted by: "nico css" <nico@cybersuperstore.com>
Nice move to go diesel. As turbine costs come down it will come so close to
the cost of recip powerplants that a large portion of recip prospects will
prefer to upgrade.
Pity that they couldn't find someone who speaks English to write their
website content.
Nico
-----Original Message-----
From: owner-commander-list-server@matronics.com
[mailto:owner-commander-list-server@matronics.com] On Behalf Of
BobsV35B@aol.com
Sent: Monday, May 29, 2006 12:43 PM
Subject: Re: Commander-List: Re: Diesel Daydreams
--> Commander-List message posted by: BobsV35B@aol.com
Good Afternoon John,
My totally non fact based comments inserted as appropriate!
In a message dated 5/29/2006 1:09:33 P.M. Central Standard Time,
john@vormbaum.com writes:
1) How might the Merlyn conversion be OK with the FAA, but the Centurion
engine wouldn't?
OB --It All Depends!
If the Merlyn Conversion was approved before the Part 36 standards were
written, it would still be OK. Or maybe it does meet the Part 36 criteria!
2) The fuel consumption is greater on the Merlyn increase...wouldn't it be
easier to plead your case for a conversion with a lower SFC?
OB ---Fuel consumption and efficiency are not subject to FAA approval so it
would have no bearing at all on any approval. However, I agree that the
lower
burn and greater efficiency would be a BIG selling point to the users.
3) The diesel props turn considerably slower than the avgas props
(2000-2100
vs. 2575 I believe), which should make LESS noise, right?
OB --- Good point.
Actually, if there is no application for a gross weight increase, I don't
think they have to meet the Part 36 criteria, but I am not sure of that.
In any case, quiet is good!
4) Centurion has retrofitted a Duke with the 4.0 engine, and that's working
out fine, but the diesels at 606 lbs. (with all accessories) weigh less
than
an IO-541. It's still a lot heavier than an IO-540....so I think a
break-even GW would be a nice target, maybe. See the Duke at
http://www.dukeb60.de/ under "news"
OB --- Sounds good to me.
5) The Duke stats list the noise level as lower than they Lyc at 78db(A).
This sounds pretty good to me (ewww...a pun).
OB --- That's even better.
Happy Skies,
Old Bob
AKA
Bob Siegfried
Ancient Aviator
Stearman N3977A
Brookeridge Air Park LL22
Downers Grove, IL 60516
630 985-8503
Message 11
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| Subject: | Re: Any thoughts on FLAPS? |
--> Commander-List message posted by: CloudCraft@aol.com
In a message dated 28-May-06 23:54:44 Pacific Daylight Time,
rsrandazzo@precisionmanuals.com writes:
I found that performance (we are at 5200' MSL) was better with the flaps at
10, so this would seem to be my preference.
I have not scientifically conducted any takeoff distance/climb performance
measurements yet, obviously.
Anyone have any hard-fast logic on this?
<><><><><><><><>
Robert,
In the words of Donald Rumsfeld, "There are things we know, there are things
we don't know and there are things we don't know that we don't know."
I know a few things about Commanders, I know there are a few things I don't
know about Commanders, and the rest is obvious.
I have never been able to figure out why the 685/690 airframes are zero flap
take-off models.
I found 10 degrees of flaps to be really effective on the 685; I operated
mostly out of Lee's Summit in Missouri (KXLT) at 1000' on a 4010' runway. I
could see the end of it; it was too short.
Things I know: 10 degrees of Commander flaps are lift. More than that is
drag. More than half flaps is a lot of drag.
Ted Smith airplanes (Commander, Aerostar, Jet Commander / Westwind) sit at a
negative angle of attack on the ground. For the science fans in the crowd,
this was something I intuited and was confirmed by Ron Smith, Ted Smith's son.
The negative angle of attack stance serves you on a short field landing but
is something you have to overcome on take-off.
This explains the "leaping into the air" as Donnie has discovered. If one
accelerates without back pressure on the yoke a Commander will pearl dive and
then with a hefty pull at your preferred Vr, you'll overcome the negative AOA
and leap.
Try this: have a companion stand outside at the tail and yell to you when the
elevator is streamlined. Make note of where the yoke is. Now hold the
yoke there at the start of your next take-off roll.
As you accelerate, the amount of back pressure to hold a streamlined elevator
will become less and you'll smoothly fly off. (The bob weight for pitch feel
will make you exercise a bit at each take-off; this counts towards your
weekly gym time.)
If anyone out there knows -- or has anyone they can reach back to, who was
involved with the 690 airframe design and certification who can enlighten me as
to why this is a zero flap take off (per the AFM) please do let me know. One
theory I've heard is that the straight wing stub gave more lift than the
continuous dihedral wings on other models and therefore flaps were not necessary.
My experience in the 685 does not bear this out. On the Turbo Commanders,
there's just so bloody much power and airflow over the inboard wing section
that the take-off is a brief blur anyway and flaps would just be ... silly.
David Maytag, do you have any insight into this mystery? You and your family
have been around this model longer than a week.
Wing Commander Gordon
Life is not simple anywhere. Probably less so elsewhere.
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