Retracting Flaps 1 to up? I think I found out when to do it

[victorlima01 4]

Hi guys. I read in a 777 flight manual that the PF should call for the next flap setting when within 20kt of that flap maneuvering speed. According to the Boeing Manual, "acceptable maneuever margin exists at speeds 20 knots below the recommended maneuver speed for each flap position."So from my interpratation at least on that aircraft during acceleration and flap retraction it is correct to go from flaps 5 to 1 when you're within 20 kt of the green number "1" on the speed tape. Now my question is whether that is applicable to the 747. And the reaosn I ask is that I have been selecting flaps Up only when arriving at the flaps up maneuvering speed indicated by the green "up" next to the speed tape. The problem with this is that that particular maneuvering airspeed is usually within a couple of knots of the red zone in the speed tape, and I've unwillingly shot above that zone a couple of times while the flaps were in transit. I bet that doesn't happen in real life and I just wanted to perform a correct retraction schedule. Any ideas?Best Regards,Victor Limahttp://www.precisionmanuals.com/images/forum/800driver.jpg

[michal 44]

>So from my interpratation at least on that aircraft during>acceleration and flap retraction it is correct to go from>flaps 5 to 1 when you're within 20 kt of the green number "1">on the speed tape. Victor,You should do it a bit later - when you are exactly on the "1". Not before. Or even tad later. Sounds like you are doing too soon and the red bricks are creeping up on you dangerously close from below.There was a huge discussion on the subject on the old forum. Lufthansa pilots even add some extra safety margin which was described there.Michael J.WinXP-Home SP2,AMD64 3500+,Abit AV8,Radeon X800Pro,36GB Raptor,1GB PC3200,Audigy 2http://www.precisionmanuals.com/images/forum/747400.jpghttp://www.hifisim.com/images/asv_beta_member.jpg

[ronzie 21]

Mike Ray wrote in his book on the 700 series for simmers that when doing an approach to go to the next flap setting as soon as you reach the speed tape previous bug such as soon as reaching flaps2 command flaps5. This allows for pilot reaction and extension time and insures you at the correct Vref for the flaps setting by the time you get there - in other words you are padding in advance cautiously to avoid stall (or below Vref, anyway).Now if we invert this practice for a departure we should reach the next flaps up bug before retraction to enable the same padding. In other words, you do not retract flaps 1 until you get to flaps up. You will not exceed max manuvering speed within that one step.

[victorlima01 4]

Thanks for the input guys. I guess that rule only applies to the 777 then. I'll continue to do it the way you guys are suggesting.Best Regards,Victor Limahttp://www.precisionmanuals.com/images/forum/800driver.jpg

[Guest Paragon]

I'm no pilot so I can't say if this is standard procedure, but after watching the DVD with Cathay Pacific I think that you should select, say flap 5 when the speed reaches the flap 5 on the speedtape and so forth...at least that's what they do in the DVD.-Mikkel