aircraft stalling on take off

[fifthtexas]

i am new to fsx have got qw757 and when taking off i keep stalling, i have no idea why

 

i start off putting flight planner set route up start off at gate.

i set my aircraft up, flaps 15, RTO, Autobrake armed.

get runway from ATC.

go to FMC. load Flight plan, activate and execute

put in reserve, cost index - execute.

depart i put in runway from ATC and execute

taxi to runway, set F/D to on, A/T to on.

get clearance line up on runway, put heading on runway, set speed to 250 and set altitude 4000 to ATC instructions.

I then hit EPR and aircraft goes through to V1, V2, rotate.

i climb up 10-15 degrees, retract landing gear, set flaps back to 1 on reaching 1000 i turn on autopilot

but then this where it goes all wrong, plane goes into a stall. where have i gone wrong?

[aeroplaneman]

Are your LNAV and VNAV switches on?

[jeroen79]

Do you also stall if you try to hand fly the same take off?

What vertical speed did you set?

Are the engines increasing power when you start to climb?

[fifthtexas]

hi

yes put on EPR and engines and thrust is full take off ok, climb to 1000 put on autopilot as soon as i do aircaft goes into a stall, vertical sped set +2000.

i am new to fsx i am sure i have set up flight planner ok, set up FMC i have no idea why this happens

[fifthtexas]

hi

no i never set LNAV or VNAV i was going on tutorial for beginners.

do i switch these on before take off?

i have only set my speed, altitude, vertical speed, set F/D on and A/T on.

retracted flaps to 1. retracted gear. have i missd something out.

i am sure i have set FMC correctly.

[evm]

What happens exactly when you switch on the AP? Do the engines power down or does the plane pitch up until it stalls?

 

Did you set up your TMS panel correctly so that you get an EPR of about 1.7+?

 

Also check this post, very helpful.

 

http://qwsim.flight1.net/forums/qw-tutorial-using-the-757-fms-w-sample-flight_topic3519.html

[PPSFA]

If you are stalling it's because your speed is too slow for your weight. At what speed are you rotating, and at what speeds are you retracting the flaps?

[napamule2]

The minute you turn on AP the PITCH TRIM is trying to 'climb' to 4000 ft (even tho you are sitting on the runway). So, on rotation you have +20.0 of pitch trim and the AP can not set it back fast enough to prevent the stall. You 'loose' it and can't recover. So, do not turn on AP until you rotate and are climbing. Throttle control is not 'needed' either (s/b 100% on take off anyway-dah). That should do it.

Chuck B

Napamule

[fifthtexas]

hi

sometimes it works ok, sometimes not, i have no idea why.

afetr seting up planner F/D and A/T on

Set EPR take off ok to right speed, climb to 1000 raise gear flaps still set to 15, all is ok until, i turn on AP

the aircraft goes into a steep angle and stall, have tried different heights, setting flaps to 1 still happens.

i set V/S TO +2000. no idea why it works ok sometimes and not other times

[napamule2]

The minute you turn on AP the PITCH TRIM is trying to 'climb' to 4000 ft (even tho you are sitting on the runway). So, on rotation you have +20.0 of pitch trim and the AP can not set it back fast enough to prevent the stall. You 'loose' it and can't recover. So, do not turn on AP until you rotate and are climbing. Throttle control is not 'needed' either (s/b 100% on take off anyway-dah). That should do it.

Chuck B

Napamule