Flaps

[Guest alpha2003]

Hi everybody.I have a big understanding problem.So 737 Takeoff with flap5. When i am reaching V2+15 i set Flaps 1 but why can i do this so early?I dont have reach the maneuverspeed 1. Isnt it dangerous?And why do i have to set Flaps 1 at the minimum maneuverspeed and not at Maneuverspeed 1?Greets Markus

[basa 0]

Markus, your explanation is a bit confussing.There are some takeoff and flap retraction procedures in the 737.I often use this one:00.- Flap position = 501.- LNAV and AT armed02.- MCP speed: set V203.- Stabilize turbines at 40% N104.- Release brakes05.- Press TOGA button06.- At V1 hands off the throttles07.- At VR rotate at 3

[Guest alpha2003]

And this ist the point i will discuss now.in the manual, it is descried, that you have to set at v2+15 flaps1 and at 1 set Flaps Up.And at the Landing you must set flaps 1 early at "UP".So why is the procedure so different?and why do i have to fly with flaps 40 at landing and can takeoff with flaps 5. but my airspeed is so low?

[basa 0]

Uh...I do not remember where in the manual that strange thing is said...On approach your speed is going down: You set flap-1 when passing the UP mark because you are "leaving" the flaps-UP safety region, and you "enter" the flap-1 safety region, so you set flap 1...and so on.And viceversa, on takeoff and initial climb your speed is going up: You set flaps-UP when passing the UP mark because is "the door" to the flaps-UP safety region...And as you know, takeoff and landing are not the same thing...they are not.At takeoff:You want to go up, don't you?, so your engines are almost at max power, maybe 95%, and you want to go up with the less possible drag (flap-5)At landingYou want to go down, don't you?, so your engines are at mid power, maybe 65%, and drag is not a problem (it is even good as is slowing you)(flap-30)Different circumstances require different configurations.Jose Luis

[Guest alpha2003]

Thanks for your answer.you can see the takeoff procedure at normal procedure 5-10.So at the pfd you can see the max speed section and the stall section and stick shaker speed. So when you see the stall speed from flaps 1 and the maneuverspeed there is a big difference between. So why do i have to set the flaps so early?How are the maneuverspeed calculated?and for example you have a v2+10 160 knots and you can fly until your acceleration with flaps 1. you can set your flaps 1 at v2+15. But you are also above the stall speed.But when you are going to land you have to fly at 160 for example with flaps 15.So why is there the difference?