UAL and Flaps 40

[Mach 80]

Back in the UAL 727 days I believe they locked out the Flaps 40 position so Flaps 40 couldn't be used. I think the same on the 737. Anyone know for certain why? I am guessing for noise or fuel burn or a larger airspeed margin to placard speeds or to reduce stress on the flaps for maint. reasons.

 

[Golden Falcon]

I would guess go-around performance limitations..

 

[FLYLOW22]

Noise restrictions... Phase 2 or 3 (one of em) mods that were put on the 727 included extending the exhaust portion of the engine nacelle and limiting the flaps to 30 so more power (noise) wasn't necessary to maintain the decent profile.

 

[pilotyip]

on the DC-9 they blocked out flaps 50. military still used them in the C-9B

 

[Sluggo_63]

Noise restrictions... Phase 2 or 3 (one of em) mods that were put on the 727 included extending the exhaust portion of the engine nacelle and limiting the flaps to 30 so more power (noise) wasn't necessary to maintain the decent profile.

This is why. I'm on the 727 at FedEx and Flaps 40 is blocked for the same reason.

 

[Chairman]

Flaps 40 were not locked out at UAL on the 737 other than by the airplane if you were going to fast I think 158kts you could move the flap handle but they would not move if you were to fast. If you were below the max extend speed they came out just fine although many pilots shy'ed away from ever using flaps 40

 

[FLYLOW22]

The one's I was writing about were safety locked and wired closed past 30 degrees.

 

[75 Driver]

Multiple answers: Flaps 40 definately locked out on some noise kits,

However long before that some airlines locked out flaps 40 due to some awfull landings and damage from said landings.

Remember some airlines really do not hire aviators, they hire people that will do what they are told and get along with others.

 

[Mach 80]

Yes, I was talking about before noise kits. I think UAL had them locked out on the 737-200's and/or 737-300's.

 

[bluechunks]

Yes, I was talking about before noise kits. I think UAL had them locked out on the 737-200's and/or 737-300's.

FWIW, UA did not lock out the 737-300/500.