Flaps usage

D

David Ward Sandidge

Filing Flight Plan
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Glenn Miller
I saw a thread about flaps deployment on here a while back, and I couldn't help but comment after reading some entries. As difficult as it may be to understand, on those light airplanes which have the more common type of airspeed indicators with only a white arc painted on the face WITHOUT varying degrees and speeds of flap deployment, it is NOT okay to deploy any fraction of flaps above the airspeed depicted at the top of the white arc. I know it makes perfect sense to state that if it is legal to deploy full flaps at 84 kts (top of the white arc), then you may deploy one degree or five degrees, or even ten degrees of flaps at 85kts. That does make sense... However, it is not legal to do so. The flap operating range is just that: The Flap Operating Range. Do not lower any degree(s) of flaps if you are faster than the speed depicted at the top of the white arc.
 
I wonder what would happen if I mention that a pilot is authorized to violate any rule he needs to during an emergency? Some things are not necessarily safe, but they are legal...
 
SkyChaser said:
I wonder what would happen if I mention that a pilot is authorized to violate any rule he needs to during an emergency? Some things are not necessarily safe, but they are legal...
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You would be corrected… it’s any rule “of this part to the extent required to meet that emergency.”
 
David Ward Sandidge said:
I saw a thread about flaps deployment on here a while back, and I couldn't help but comment after reading some entries. As difficult as it may be to understand, on those light airplanes which have the more common type of airspeed indicators with only a white arc painted on the face WITHOUT varying degrees and speeds of flap deployment, it is NOT okay to deploy any fraction of flaps above the airspeed depicted at the top of the white arc. I know it makes perfect sense to state that if it is legal to deploy full flaps at 84 kts (top of the white arc), then you may deploy one degree or five degrees, or even ten degrees of flaps at 85kts. That does make sense... However, it is not legal to do so. The flap operating range is just that: The Flap Operating Range. Do not lower any degree(s) of flaps if you are faster than the speed depicted at the top of the white arc.
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Technically, some planes say in the POH you may exceed the white arc up to higher speed x for the first notch of flaps. In general, your principle still applies, though.
 
According to the POH for a C-172R VFE for 10° of flaps is 110kts. The top of the white arc is at 85kts. Why should I trust that sgoti knows better than the people at Cessna that wrote the POH? The placard in the plane matches the information in the POH.

BC424CAF-84DE-4C3C-B694-60C9A1D760F9.jpeg 1F159475-FF38-4A0A-8C9A-FECDB9E4D4C6.jpeg
Placard:
2478646A-D9AB-46CF-8EC4-312BEACCC576.jpeg
 
Wheels said:
According to the POH for a C-172R VFE for 10° of flaps is 110kts. The top of the white arc is at 85kts. Why should I trust that sgoti knows better than the people at Cessna that wrote the POH? The placard in the plane matches the information in the POH.

View attachment 109397 View attachment 109396
Placard:
View attachment 109398
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I was going to reply something similar. The white arc is not the operating limitation, the POH is. The white arc is just a reference.

Now to stop feeding the troll.
 
This is patently untrue. In addition to what is posted above, Cessna 182s also have a higher 10 degree flap speed than the white arc.

Now, that being said, you have to know that you are adding additional forces to the flaps when you do that. I have seen evidence in 182s that higher speed flap deployments can cause flap track bracket cracks, though I don't have direct evidence to say that is from actually operating within the POH requirements.
 
What a first post. You do know there are exceptions to your legal opinion, several of which have been mentioned already?
 
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Quite a number of flap systems have up stops that hold the flaps in that up position. The moment you add even 1 or 2 degrees of flaps you move those flap loads from the stops to the actuating mechanism which likely will not withstand near as much load as the up stops. It may also allow the flap to warp, since often there are multiple up stops and often only one actuation point.

I am aware of at least one event where the flaps were overloaded and the failed about mid flap. The actuator was at the root. The pilot was extremely lucky that both flaps failed at basically the same time in the same place and the airplane was still flyable for a successful landing.


Brian
 
Why would anyone add flaps above flap speed? That’s about 1.5x more than flaps useful speed!
 
David Ward Sandidge said:
I saw a thread about flaps deployment on here a while back, and I couldn't help but comment after reading some entries. As difficult as it may be to understand, on those light airplanes which have the more common type of airspeed indicators with only a white arc painted on the face WITHOUT varying degrees and speeds of flap deployment, it is NOT okay to deploy any fraction of flaps above the airspeed depicted at the top of the white arc. I know it makes perfect sense to state that if it is legal to deploy full flaps at 84 kts (top of the white arc), then you may deploy one degree or five degrees, or even ten degrees of flaps at 85kts. That does make sense... However, it is not legal to do so. The flap operating range is just that: The Flap Operating Range. Do not lower any degree(s) of flaps if you are faster than the speed depicted at the top of the white arc.
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Except in an emergency it's generally considered to be a really bad idea to try to operate outside of an aircrafts published limits.

Why take that added risk?
 
As others have stated, the OP is wrong.

You have to comply with your POH Operating Limitations Section. And the white arc IS an operating limitation, however it is not an overall limit for ALL flap operations/positions

If you check, the top of the white arc is the "maximum speed permissible with FULL (my emphasis) flap extension." Direct quote from my Mooney POH.

That said, there are some aircraft that only have one maximum speed for flap use.
 
Pinecone said:
As others have stated, the OP is wrong.
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Well, he did say
David Ward Sandidge said:
WITHOUT varying degrees and speeds of flap deployment,
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So he's probably taken into account aircraft which do have different maximum speeds for different degrees of flap extension. If not, then I guess he's a fairly new pilot who still thinks the limitations of the only airplane he's ever flown are universal.

I'm more wondering what prompted it as a first post.
 
David Ward Sandidge said:
I saw a thread about flaps deployment on here a while back, and I couldn't help but comment after reading some entries. As difficult as it may be to understand, on those light airplanes which have the more common type of airspeed indicators with only a white arc painted on the face WITHOUT varying degrees and speeds of flap deployment, it is NOT okay to deploy any fraction of flaps above the airspeed depicted at the top of the white arc. I know it makes perfect sense to state that if it is legal to deploy full flaps at 84 kts (top of the white arc), then you may deploy one degree or five degrees, or even ten degrees of flaps at 85kts. That does make sense... However, it is not legal to do so. The flap operating range is just that: The Flap Operating Range. Do not lower any degree(s) of flaps if you are faster than the speed depicted at the top of the white arc.
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Isn’t there a minimum age limit to post here?
 
The act is self punishing. Ignore white arc. Throw out flaps while whenever you want. Left flap is torn away, right flap remains. Plane makes a smoking hole in the ground.
Offender is punished and never violates white arc again. :D
 
Jeff Oslick said:
Alternatively, might need a maximum age...
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I see. You make an oblique (and snarky) comment about my age, yet you chose not to list your own in your profile.

The OP, in a first post, instructed us all on aircraft configuration.

Pretty cheeky. Pretty presumptuous. Pretty childish, regardless of age.

Hence, my comment.
 
orca64 said:
I see. You make an oblique (and snarky) comment about my age, yet you chose not to list your own in your profile.

The OP, in a first post, instructed us all on aircraft configuration.

Pretty cheeky. Pretty presumptuous. Pretty childish, regardless of age.

Hence, my comment.
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Maybe I'm thick-headed, but I don't see any indication that @Jeff Oslick is making a personal comment towards you.

I thought about making that comment myself - but chose not to. I've been snarky enough lately, and am trying to work on my snarky:helpful ratio. I can guarantee while that not-published post nearly came out of my fingers, I wasn't thinking of you at all, @orca64 - I have no idea how old you are. In fact, I occasionally have to remind myself how old I am.

Maybe, @orca64 , you're a little age-sensitive yourself, and see things as personal attacks when they're not?
 
Rgbeard said:
Maybe I'm thick-headed, but I don't see any indication that @Jeff Oslick is making a personal comment towards you.

I thought about making that comment myself - but chose not to. I've been snarky enough lately, and am trying to work on my snarky:helpful ratio. I can guarantee while that not-published post nearly came out of my fingers, I wasn't thinking of you at all, @orca64 - I have no idea how old you are. In fact, I occasionally have to remind myself how old I am.

Maybe, @orca64 , you're a little age-sensitive yourself, and see things as personal attacks when they're not?
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Communications experts tell us as much as 70% of human communication is not the words themselves but physical and physiological. We're at therefore a 70% disadvantage communicating by text only particularly with strangers.

I try not to look for offense where I don't know it's fully intended and until proven otherwise not everyone is simply trolling to stir the pot.

Sometimes it helps, sometimes it doesn't.
 
orca64 said:
I see. You make an oblique (and snarky) comment about my age, yet you chose not to list your own in your profile.
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No targeted offense meant, just my general snarkiness. I have no idea how old you are.

Given that I post under my real name, it would take about 20 seconds of googling to find out my age.
 
I wasn't planning on pulling my flaps at 101MPH but now I feel like I have to. It's not easy being a rebel sometimes. Thanks for nothing.:frown2:

XHNWsz4.jpg

And what do I do in the Champ with no flaps?
 
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Jeff Oslick said:
No targeted offense meant, just my general snarkiness. I have no idea how old you are.

Given that I post under my real name, it would take about 20 seconds of googling to find out my age.
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Fair enough.

Is that goggle thing on the interweb?











just kidding.
 
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