Use of Flaps

[AdamZ]

I just read an article in the March edition of Plane and Pilot about flap usage. To paraphrase the section of the article abut flap extension speed it said that Vfe ( unless otherwise noted in your POH) is only the top speed for full extension of flaps and that there is no reason you can't extend flaps above Vfe. I think they gave a general rule of thumb that one notch of flaps can be extended at either 10kts or 10% ( I think it was Kts) above Vfe and the second notch at 5 kts or 5% above Vfe.
What scenarios in GA would call for extension of flaps above Vfe? I have to say its confusing because it goes against everything I was taught about flap deployment in my training

 

[poadeleted3]

I just read an article in the March edition of Plane and Pilot about flap usage. To paraphrase the section of the article abut flap extension speed it said that Vfe ( unless otherwise noted in your POH) is only the top speed for full extension of flaps and that there is no reason you can't extend flaps above Vfe. I think they gave a general rule of thumb that one notch of flaps can be extended at either 10kts or 10% ( I think it was Kts) above Vfe and the second notch at 5 kts or 5% above Vfe.
What scenarios in GA would call for extension of flaps above Vfe? I have to say its confusing because it goes against everything I was taught about flap deployment in my training

I suppose you could extend partial flaps above the white line if you were trying to slow down. I know the top of the white is supposed to be for full flap extension, but I have no way of knowing what the safe limits are for partial flap extensions. I don't do it, personally. I'll just wait to get into the white before lowering any flaps, unless I happen to run across information for safe speeds for partial flaps in the POH.

 

[Greebo]

I think that generally you need to refer to your Pilot Operating Handbook for the specific plane in question to determine at what speeds flaps can be deployed. If P&P is saying (paraphrased) "go ahead and deploy partial flaps at higher speeds whenever you like" then they're giving potentially very bad advice.

Now the C172 does, generally, allow for 10 % deployment (NO MORE) at or below 110 kts if I recall correctly (IIRC).

And as for when to use them?

Well - at MTN it gets a little busy sometimes, and we have a pretty long downwind for a C172... so I will frequently enter the pattern at 100 kts or so and only start to slow down when about midfield. I'll put in the first 10 degrees while at 100kts to help slow down to 80, while leaving the power in, and then pull power when abeem.

Other than using them as brakes, however, I don't know of any particular reason to use them at higher speeds, and I'd never use more than the POH allows.

 

[fgcason]

I just read an article in the March edition of Plane and Pilot about flap usage. To paraphrase the section of the article abut flap extension speed it said that Vfe ( unless otherwise noted in your POH) is only the top speed for full extension of flaps and that there is no reason you can't extend flaps above Vfe. I think they gave a general rule of thumb that one notch of flaps can be extended at either 10kts or 10% ( I think it was Kts) above Vfe and the second notch at 5 kts or 5% above Vfe.

What are their references for this? There are always safety buffers in designs and limits but buffers are good.

I can see how they can come up with an assumption like that. If you can put 40deg in at 90kts, why not 10 deg at 100kts since 10deg is likely to have less stress forces involved. That doesn't mean it's right though. The designers may have be thinking no flaps above x kts for a reason.

What scenarios in GA would call for extension of flaps above Vfe?

Emergency? I'm not sure what kind of emergency would involve deploying flaps at high speeds. You should have better energy management skills than that.

I have to say its confusing because it goes against everything I was taught about flap deployment in my training

A little story:
A couple years ago I rented a CE172. When I got there my regular ride was down for 100hr so they gave me another one. Preflight always involves dropping the flaps and inspecting them. I start aft from the left door and as I go under the left flap, I push up on the trailing edge like I always do as I head toward the tail. This one moved - A LOT. Enough to stop me in my tracks. I turn around to take a good look. The tracks are typical rental wear patterns. The pushrod on top of the flap was slightly bent. Next to the attach bracket on both sides was cracks in the top surface of the flap about an inch longer than the bracket forward and aft. I push the flap up as if trying to retract it and the rod visibly bends. I can easily push the flap up about an inch or maybe 1.5" beyond where it should move without getting very agressive. I then go around to the right flap and it's not as bad. The rod was straight but there is a crack on the inboard side of the bracket. That was more than I needed to know. Two hours later the death trap is in the shop with a flap on the workbench and the A&P is pulling the other one off all the while grumbling about idiot pilots doing things they shouldn't to innocent airplanes.
Anyone want to bet that someone had been dropping flaps over Vfe on that one probably on a regular basis?

Just another good reason to own...

 

[poadeleted20]

Not having the article in front of me, I don't know what they actually said, and I am loath to climb up their nose based on hearsay. However,...

You have to look at the book. The C-172 has a higher max speed for extension of 10 degrees of flaps than for full flaps, and the top of the white arc is the max speed for full flap extension. However, the flap switch is clearly labeled with the max speeds for both 10 degrees and any more.

OTOH, the AA-5A/B has but one speed for any degree of extension, be it 1 degree or 45. Extend any flaps above that speed and you're begging for flap system damage. In fact, most Grumman pilots try to get well below the max flap extension speed before extending more than 1/3 flaps in order to maximize flap system component life.

So, anyone who makes the blanket statement that it's OK to extend partial flaps above the top of the white arc or Vfe, or that there's some blanket rule of thumb allowing partial flap extension above book Vfe based on percentages, is giving out bad information. However, some, but not all, airplanes do have higher partial flap Vfe's. The correct answer lies in the particular aircraft's limitations, which are in the Type Certificate Data Sheet, the Limitations section of the POH/AFM, and the placards in the aircraft.

 

[wsuffa]

What are their references for this? There are always safety buffers in designs and limits but buffers are good.

I can see how they can come up with an assumption like that. If you can put 40deg in at 90kts, why not 10 deg at 100kts since 10deg is likely to have less stress forces involved. That doesn't mean it's right though. The designers may have be thinking no flaps above x kts for a reason.

It may never have been tested. On my plane, the book specifies max flap extension speeds of 151 KIAS of 0-20 degrees, 121 KIAS for 20-20, and 111 for 25-35.

Limits are limits, and once you exceed them you become a test pilot.

Emergency? I'm not sure what kind of emergency would involve deploying flaps at high speeds. You should have better energy management skills than that.

If you have a really slick plane without speed brakes, this can happen if ATC gives you a slam-dunk or a really tight crossing restriction. On an emergency descent, same deal. It SHOULDN't happen, but it can.

On some planes (mine included) the initial flap speed is above the gear operating speed. You can use 20 degrees of flaps to get some drag out there and then drop gear. Slips can be quite effective, too.

A little story:
A couple years ago I rented a CE172. Anyone want to bet that someone had been dropping flaps over Vfe on that one probably on a regular basis?

Just another good reason to own...

Agree: Good reason to own. I'd wonder what else is cracked. Might not be overspeed flap extension, might be some other cause. One more reason that I don't want to own a trainer....

 

[Dave Siciliano]

There are several limitations that were added as a consequence of litigation in the Bonanza POH. Many of the folks that truely understand their aircraft and have been flying for years understand these and know where they can safely vary from the POH. It's not something that should be done without complete understanding, and, if it results in damage or an accident, it certainly can cause problems for you.

A lot of long time Bonanza pilots takeoff using flaps; the POH says not to and if you research why, it was a modification in the POH because of an accident where a pilot didn't raise the flaps after takeoff when they should have. Same thing with baffles in main tanks and the useable fuel limitation. Lots of folks will tell you all the fuel is there is you fly in trim (and I've tried it).

In general, 10 degrees of flaps adds very little extra drag, but there are different kinds of flaps. In my Bonanza, 10 degrees of flaps can be used above the white arc. But why would you bother? Are you trying to slow? Are you putting them out incrementally incase they don't deploy evenly? If you only add flaps when the runway is made, how would this apply?

Best,

Dave
A-36TN ADS

 

[Ed Guthrie]

I just read an article in the March edition of Plane and Pilot about flap usage. To paraphrase the section of the article abut flap extension speed it said that Vfe ( unless otherwise noted in your POH) is only the top speed for full extension of flaps and that there is no reason you can't extend flaps above Vfe. I think they gave a general rule of thumb that one notch of flaps can be extended at either 10kts or 10% ( I think it was Kts) above Vfe and the second notch at 5 kts or 5% above Vfe.

Assumption #1 - The above accurately conveys the P&P article.
Assumption #2 - The P&P article actually taught that this is applicable to any aircraft.
Assumption #3 - The author is a CFI.

Assuminng the above are true & correct,

Conclusion: The FAA needs to research this CFIs certificate & home address and send a FSDO inspector out to his/her house with a certificate shredder.

§ 91.9 Civil aircraft flight manual, marking, and placard requirements.
(a) Except as provided in paragraph (d) of this section, no person may operate a civil aircraft without complying with the operating limitations specified in the approved Airplane or Rotorcraft Flight Manual, markings, and placards, or as otherwise prescribed by the certificating authority of the country of registry.

Looks like a cut & dried 91.9 bust to me.

What scenarios in GA would call for extension of flaps above Vfe?

The POH/TCDS approves partial flap extension above Vfe.

I have to say its confusing because it goes against everything I was taught about flap deployment in my training

You obviously had a better CFI than the editor(s) of Plane & Pilot appears to know.

 

[Brian Austin]

Go outside the POH numbers and you become a test pilot. My $.02.

 

[Jeff Oslick]

Many (not sure if all) Cessna 182 models allow for 10 degree flaps below 140 kts, the rest below top of white-arc. However, many 182s suffer from cracks on the trailing edge of the flaps. Although I'm not going to draw a direct cause-effect line here, the problem is, how many times is the flap's sheet metal supposed to endure the stress of a max-speed deployment before starting to wear out? Ever stick your hand out the window of your car while going 140 kts . That's what you're doing to your flaps!

I think if you want the hardware to last, you should treat the POH numbers with a lot of respect - rather than pushing to see how fast you can go while dropping the flaps, why not just plan ahead a bit better and try to be 10% (or more) below the POH numbers while using flaps?

Just my $0.02.

Jeff

 

[Dave Krall CFII]

Plan ahead as always as one should and you won't need no stinking flaps at high speed... <G>
Do pilots ever use slips and/or aggressive slips anymore to slow down ?
One Cub I flew regularly didn't even have flaps, nor did many planes from the stick & rudder era.

 

[Skip Miller]

Do pilots ever use slips and/or aggressive slips anymore to slow down ?

Slow down and descend? Yep! Saturday coming in to HPN, kept myself high (flew downwind for 11 over the arrival path for 16, kept it high) and was then offered a short approach to 11 in front of other traffic coming in to 11. Only way to do it was full flaps and a full rudder slip. I almost crossed runway 16 (made the last turnoff prior) but the landing traffic on 16 was issued LAHSO so crossing was authorized.

-Skip

 

[RotaryWingBob]

The PA28-181 POH is explicit:

Maximum Flaps Extended Speed (Vfe) - Do not exceed this speed with flaps extended.

There's nothing in there that says that partial extension above Vfe is ok, and the normal procedures section explicitly says in the approach and landing checklist:

Flaps ....... set - 102 KIAS max

 

[AirBaker]

A lot of long time Bonanza pilots takeoff using flaps; the POH says not to and if you research why, it was a modification in the POH because of an accident where a pilot didn't raise the flaps after takeoff when they should have. Same thing with baffles in main tanks and the useable fuel limitation. Lots of folks will tell you all the fuel is there is you fly in trim (and I've tried it).

In general, 10 degrees of flaps adds very little extra drag, but there are different kinds of flaps. In my Bonanza, 10 degrees of flaps can be used above the white arc. But why would you bother? Are you trying to slow? Are you putting them out incrementally incase they don't deploy evenly? If you only add flaps when the runway is made, how would this apply?

Best,

Dave
A-36TN ADS

I always wondered about why the Bonanza POH didn't have the use of flaps for takeoff. I know the book 'Flying the Beech Bonanza' mentioned the use of them, but was never sure.

 

[Dave Krall CFII]

Slow down and descend? Yep! Saturday coming in to HPN, kept myself high (flew downwind for 11 over the arrival path for 16, kept it high) and was then offered a short approach to 11 in front of other traffic coming in to 11. Only way to do it was full flaps and a full rudder slip. I almost crossed runway 16 (made the last turnoff prior) but the landing traffic on 16 was issued LAHSO so crossing was authorized.

-Skip

That's cool.
(Or slip to slow down without descending)
Unfortunately most of what I see is half baked, wishy washy little gestures towards slipping that don't do anything much.

 

[bbchien]

"But inspector, I read an article in redneck aviaiton that said I could do that!". Sheesh. _&_ranks right up there with "Popular Mechanics". They should know better....CFI.

 

[AdamZ]

Just so there is no confusion and in relation to Ron's and Ed Guthrie's posts I went and read the article again. It is entitled WHAT'S ALL THIS FLAP ABOUT? Counting on that extra lift can be a drag By: Vince D'Angelo Plane & Pilot March 2005 p62. "

see this link http://www.planeandpilotmag.com/content/2005/mar/flaps.html

"At the other end of that white Arc is the maximum speed for full-flap extension. Speeds beyond this can cause structural damage to fully extended flaps. There is no reason, however why flaps can't be partially extended beyond the top of the white arc (unless the aircraft manual or POH states otherwise). A rule of thumb is 10 knots higher for one notchand five knots higher for two notches of flaps."

Ed the only assumption I can't confirm is that Mr. D'Angelo is a CFI.

Bruce, wasn't relying on the article as gospel, but rather questioning it because it went against my CFI's teaching.

 

[Ken Ibold]

Ed the only assumption I can't confirm is that Mr. D'Angelo is a CFI.

Vincent R. D'Angelo
CP-SEL, IA
PP-MEL
CFI-SEL, IA

 

[John J]

The book for my plane really does not cover the use of flaps for take off very well. I am flying a C-33 Debonair/Bonanza. What I do remember so well with the early Bonanzas is some of the older pilots used to count to 3 with the switch down = 5 degrees. It changed the camber of the wing enough to give just a touch of extra lift without drag. I do this on short field take offs and yes it does work. The later Bo has the power to get you to speeds that enables a decent climb angle and rate without flaps. I never lower the flaps above the white arc for it puts a real strain on them as well it lowers your manuvering speed by quite a bit if you are light in weight. The Piper Apache if you lowered the flaps at the end of the white arc it ballooned with a vengence. My head hit the ceiling once and that was enough.

john j

 

[bbchien]

Hey Adam, not an engineer any longer (though the basics haven't changed). But standard practice was for a 10% overload before failure. That doesn't leave much for the flap rails- besides overstresses affect malleability and crack resistance. Also aerodynamic forces go up with the square- so maybe 6 knots over and you're looking a major trouble....sigh.

 

[gibbons]

A lot of long time Bonanza pilots takeoff using flaps; the POH says not to and if you research why, it was a modification in the POH because of an accident where a pilot didn't raise the flaps after takeoff when they should have.

Dave,

I would have assumed our airplanes were close to being the same in this regard, but my POH (1995 A36) lists two take-off charts, one for flaps up, and the other for approach flaps (section V - Performance in the POH). At 15 degrees and a pressure altitude of 5653', a take-off weight of 3650 lbs and a 10 kt headwind, the no flaps ground roll shows 1900', with 3475' over a 50-ft obstacle, rotation at 73 kts. The approach flaps distances given the same situation shows ground roll of 1200', with 2350' over a 50-ft obstacles, rotation at 65 kts.

I use approach flaps on take off on occasion, like when the field is short or I'm especially heavy. Maybe it's the V-tails that have POH entries to avoid taking off with flaps??? I've never owned a V-tail.

Chip

 

[Dave Siciliano]

It may be Chip. On the Bonanza board, several owners have complained that the updated POHes state that takeoff is to be without flaps. There may be a conflict between the text and charts. Many folks don't have the modifications to the POH that were issued when it was updated. Original POHes have flaps for soft field departures. Many pilots haven't gotten updates so they can show their POH states they can use flaps (like the proverbial ostrich with its head in the sand.)

In my manual, under Normal Procedures it says, " Before Takeoff 11. Flaps - UP"
There is no provision for soft field departure under Normal Procedures. There is no adjustment for short field stated.

In performance charts, the take off distance chart lists, among other things, Flaps UP.

Perhaps someone should sue the manufacturer for not showing how to depart on a soft field or short field in the best possible manner.

 

[gibbons]

Perhaps someone should sue the manufacturer for not showing how to depart on a soft field or short field in the best possible manner.

Perhaps I should check with Beechcraft for updates to my POH! Thanks for the heads up.

Chip

 

[gismo]

I always wondered about why the Bonanza POH didn't have the use of flaps for takeoff. I know the book 'Flying the Beech Bonanza' mentioned the use of them, but was never sure.

I had three "flight manuals" for my old Bonanza and two of them had a procedure for takeoff with partial flaps, the second even had runway length info for a takeoff with partial flaps, the third didn't have either.

I also have the original "flight manual" for the Baron which contained a similar procedure and associated data for a short field T.O. This procedure involved lifting off well below Vmc and is noticeably absent from the current POH, no doubt due to the extreme difficulty in recovering from an engine failure under such circumstances. I have used the procedure a few times when departing a tight runway, but I'm hair trigger ready to pull both throttles and dump the nose if an engine dies. Also since I have VG's rollover isn't as big a problem on this airplane.

Getting back to the original question, there are plenty of times when I will deploy partial flaps above the top of the white arc (this is allowed by the POH). Typically I will drop half flaps as soon as I get the gear down, although I have experimented with partial flaps and gear up coming into the FAF on an instrument approach. I don't particularly like deploying flaps before the gear is down because they can mask the (early) symptoms of the gear failing to extend.

OTOH, I do think one should treat all the flap (and gear) limits as limits, not normal speeds for operation whenever possible. If the maximum speed for full flap deployment is 90 KIAS, why not wait until something less before dropping them all the way. Similarly if the POH and/or panel markings allow partial flaps at 120, waiting until you've gotten a bit slower than that is a very good habit. Remember that the aerodynamic forces are a function of the airspeed squared so even a 10% reduction in IAS makes a bigger difference (about 20%) in the mechanical stress.

IME instructors tend to teach dropping flaps (and gear) at the highest speed allowed, so that's how many pilots fly.

 

[AirBaker]

At least in the Bonanza, I don't see how putting flaps down before the gear is an issue. The airplane 'almost' needs the gear down to be anywhere close to flap extension speed.

 

[poadeleted20]

Just so there is no confusion and in relation to Ron's and Ed Guthrie's posts I went and read the article again. It is entitled WHAT'S ALL THIS FLAP ABOUT? Counting on that extra lift can be a drag By: Vince D'Angelo Plane & Pilot March 2005 p62. "

see this link http://www.planeandpilotmag.com/content/2005/mar/flaps.html



"At the other end of that white Arc is the maximum speed for full-flap extension. Speeds beyond this can cause structural damage to fully extended flaps. There is no reason, however why flaps can't be partially extended beyond the top of the white arc (unless the aircraft manual or POH states otherwise). A rule of thumb is 10 knots higher for one notchand five knots higher for two notches of flaps."

The following is being sent to the Editor of P&P:



In his article in the March issue entitled “What's All This Flap About?” Mr. Vince D’Angelo wrote:



"At the other end of that white arc is the maximum speed for full-flap extension. Speeds beyond this can cause structural damage to fully extended flaps. There is no reason, however why flaps can't be partially extended beyond the top of the white arc (unless the aircraft manual or POH states otherwise). A rule of thumb is 10 knots higher for one notch and five knots higher for two notches of flaps."



However, this was brought to my attention by an inexperienced pilot who read it as saying, “The top of the white arc only applies to full extension, and you can safely extended partial flaps per the ‘rule of thumb’ unless otherwise specifically prohibited,” and that’s just not true. Even given the caveat, Mr. D'Angelo's statement is only partially technically correct. Vfe is defined in 14 CFR 1.1 as “maximum flap extended speed,” not “maximum full flap extended speed.” Unless specifically authorized via placards or the AFM or POH, no flap extension is permitted above Vfe, and Mr. D’Angelo’s statement reads as the converse of the actual restriction. You may feel free to check this with AFS-301. In order to be correct, Mr. D’Angelo’s statement should have been worded something like this:



"At the other end of that white arc is the maximum speed for flap extension. Speeds beyond this can cause structural damage to extended flaps. However, in many cases, flaps may be partially extended beyond the top of the white arc if permitted in the aircraft placards, flight manual or POH. This capability, if so permitted, provides additional flexibility for the pilot to manage drag on the approach or in the landing pattern, but should be used only if specifically approved for that aircraft."



I think an appropriate clarification in your next issue would be a very good idea.

Ed the only assumption I can't confirm is that Mr. D'Angelo is a CFI.

Name : D'ANGELO, VINCENT R
Airman's Address : 9103 VANDERBILT DR APT 305
NAPLES, FL, 34108-2366
FAA Region : Southern
Date of Medical : Mar, 2004
Class of Medical : 2
Expiration of Class 2 privileges : Mar, 2005
Airman Certificates : Commercial Pilot
Airplane Single Engine Land
Instrument Airplane
Airplane Multiengine Land (Private Pilot)
: Flight Instructor (exp: 31-Jul-2005)
Airplane Single Engine
Instrument Airplane

 

[Ed Guthrie]

The following is being sent to the Editor of P&P: (snip)[/QUOTE]

Best of luck, but, frankly, I don't believe the editor(s) cares about technical accuracy. As my dear old father told me: Never debate with a man who purchases ink by the barrel. Might be worth purchasing the next issue just to read the response, assuming there even is a response.

 

[AdamZ]

Thanks everyone for your input especially Ron and Ed. I'm glad to see that I was not reading the article incorrectly. It is good to have a forum like this to raise such issues. I always think of my PPL as a license to learn and if I run into something that conflicts with what I have been taught I feel compelled to question it. Sometimes I learn that what I was taught is not always correct ( as in a previous discussion about throttle settings) and sometimes like this, I learn that Hey, I really was paying attention in class!

 

[Dave Siciliano]

I also have the original "flight manual" for the Baron which contained a similar procedure and associated data for a short field T.O. This procedure involved lifting off well below Vmc and is noticeably absent from the current POH, no doubt due to the extreme difficulty in recovering from an engine failure under such circumstances.

======================================================
Yep Lance!! You hit another POH modification on the head: takeoff below VMC was specifically changed in the Baron manual as the result of an accident and subsequent legal action from what I've been told.

This begs another question: how do you know you have a POH with all the latest revisions? If you're renting an aircraft, how would you know?

Dave

 

[poadeleted3]

Yep Lance!! You hit another POH modification on the head: takeoff below VMC was specifically changed in the Baron manual as the result of an accident and subsequent legal action from what I've been told.

This begs another question: how do you know you have a POH with all the latest revisions? If you're renting an aircraft, how would you know?

Dave

I wouldn't have a clue... I'm kinda depending on the book behind the seat to be accurate. Wonder how much trouble I can get into because of that?

 

[wsuffa]

I wouldn't have a clue... I'm kinda depending on the book behind the seat to be accurate. Wonder how much trouble I can get into because of that?

First place to look is the Type Cert. Data Sheet at the FAA site. If the modified manual is required by the FAA, it MAY show up there. OTOH, sometimes the changes incorporated in the TCDS are reflected in the POH/AFM without a clue in the TCDS that the POH is changed. In that case, the TCDS data is probably right, and you'll need to go back to the manufacturer to get the updated manual. BTW, on later model planes, the POH is usually serial-number specific, so you'll need to specify when talking to the manufacturer.

If the change is the result of an AD, you can check that by researching ADs. For example, the POH supplement replacement required by Precise Flight for their standby vacuum system was contained in an AD.

The Beech TCDS for the Bonanza is quite a piece of work....

 

[Ed Guthrie]

I wouldn't have a clue... I'm kinda depending on the book behind the seat to be accurate. Wonder how much trouble I can get into because of that?

Bad assumption, but the good news is that the average FSDO inspector will be as you are with respect to the current revision status.

FWIW, if the aircraft is a Mooney you go to http://www.mooney.com and then follow the links to "Service/Support" "Technical Manuals" "OM & AFM & POH Revision Status". If the aircraft if a '77 M20J the current revision is "G".

I suspect Cessna, Piper, and Beechcraft have similar sites or you will need to call the factory tech support folks.

 

[Ed Guthrie]

In case folks might actually believe the P&P advice here is a real world example --

The Mooney M20J POH states:

"Vfe Maximum Flap Extended Speed is the highest speed permissible with wing flaps in a prescribed extended position."

"AIRSPEED LIMITATIONS", "Vfe", "Maximum Flap Extended Speed" "IAS(mph)" "132" "Do not exceed these speeds with the given flap settings."

The Mooney TCDS states:

Flaps extended (full flaps) 127 m.p.h. (110 knots) IAS​

****(15° flaps) 145 m.p.h. (126 knots) IAS

**** Serial No. 24-3000 thru 24-3078.

Now, as my aircraft is SN 24-0089 the footnote reference 15° flap speed is not applicable. Mooney is pretty good about retro allowing modifications/improvements that are merely changes in specifications. However, Mooney didn't retro allow this change on previous SN's. What is different about SN's 24-3000 thru 24-3078? Your guess is as good as mine. Structural change? Probably, or else Mooney would have allowed the change on all previous airframes via a Service Bulletin. Would operating 15° flaps on the other SN M20J airframes at speeds 15 kts faster than POH published Vfe cause structural damage? Maybe. I do know plenty of M20Js out there with rib & skin damage at the flap hinge attach points.

As Ron often says, "Caveat Aviator".​

​

​

 

[wsuffa]

Ed noted the data for his Mooney.

I noted in an earlier post above the book data for my Commander. A check of the TCDS reveals that my book data = TCDS data, which is a good thing. Other models of Commander have different limits. It's worth noting that there are two basic wings on the Commander - a shorter wing used with most of the planes, and a longer wing used on the 112B and 112TC. It does make a difference....

 

[gismo]

I wouldn't have a clue... I'm kinda depending on the book behind the seat to be accurate. Wonder how much trouble I can get into because of that?

I've never heard of a bust for an out of date POH. I doubt that on a ramp check the inspector would have any way to tell, and anyway he'd probably be happy just to learn that you had a copy in the plane.

Theoretically the POH updates are supposed to be done by AD so you ought to be able to make the determination by doing an AD search on the aircraft.

 

[poadeleted20]

I've never heard of a bust for an out of date POH. I doubt that on a ramp check the inspector would have any way to tell, and anyway he'd probably be happy just to learn that you had a copy in the plane.

Theoretically the POH updates are supposed to be done by AD so you ought to be able to make the determination by doing an AD search on the aircraft.

If you substitute AFM for POH, I'd tend to agree with Lance's statement, although I can't confirm that AFM changes come out by AD, and the inspector COULD go back to the office, look up the last change date, and compare it with his notes of the check (not likely if you were good on everything else and didn't irk him in the process of the check).

But while AFM's must be on board and up to date for airplanes that have them, there's no parallel requirement for POH's -- for those planes built before the AFM requirement, the only hard requirement is that all TCDS-required placards ("operating limitations" -- the O in ARROW) be properly mounted and legible.

Of course, not having a POH in a pre-AFM plane could open you to questions about how you figured your takeoff/landing data (see 91.103(b)), but with enough knowledge, some good notes on performance, and a glib tongue, you might get past that one, especially if you're flying a REALLY old plane with no POH or other "official" book. But since there's no hard requirement for a POH, it would not be a 91.9 issue.

 

[gismo]

If you substitute AFM for POH

Right, I often confuse the two.

 

[bbchien]

Why is it that I am under the increasing impression that, what the FAA is going to do is simply make it impossible to operate anything put into service prior to 1975...

 

[poadeleted3]

Why is it that I am under the increasing impression that, what the FAA is going to do is simply make it impossible to operate anything put into service prior to 1975...

I would not be surprised. They've expressed concern more than once with the aging fleet, and the planes really weren't expected to be in service this long. Somehow, I doubt the FAA would have a hard time convincing the manufacturers to help them, either. Right now, one of the biggest arguments against buying a new $200K Skyhawk is the availability of a nice $50K Skyhawk, even though the new planes really are superior.

 

[inav8r]

Why is it that I am under the increasing impression that, what the FAA is going to do is simply make it impossible to operate anything put into service prior to 1975...

I sure hope that's not the case. We just sent our 1973 Skylane off to the avionics shop for $30,000 in upgrades!