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Can anyone tell me why my heavies require so much speed and runway to take off??? Im talking 250+ and most runways arent long enough. This happened all of a sudden. Flaps and speedbrake are NOT engaged. Did I hit a wrong button someplace???

thanks

Can anyone tell me why my heavies require so much speed and runway to take off??? Im talking 250+ and most runways arent long enough. This happened all of a sudden. Flaps and speedbrake are NOT engaged. Did I hit a wrong button someplace???

thanks

That's because they're very heavy, so you need more energy to lift that much mass. To get that much energy and airspeed, you need a lot of runway. The larger the plane, the more runway it needs, which is why you can't fit heavies on little grass airstrips.

But with most heavies, you need flaps for takeoff. Flaps increase your lift, and are good for "scooping" up the air rushing by (this is also why you take off into the wind). As the plane scoops up the air, it will lift off the ground. Generally (to a point) the more flaps you have, the shorter the runway required.

The generalized procedure for takeoff in most heavies available in FS2K2 is 5-20 degrees of flap, (or 1 + F setting on Airbus jets) and speedbrakes set to ARM. (Usually autobrakes should be on RTO). Pitch will automatically be set if you use the TOGA mode, but normally you'll want to have your pitch on the "up" side of center. (It's different in planes.)

I've never really had trouble taking off with these settings, unless there's a bad FDE. I remember I was able to lift off in a 747 on Sydney (YSSY's) cross runway at about 8,100 feet, and I lifted off with about 1500 feet to spare or something like that. I used full power and 10 degrees of flap, something like that.

Sometimes if you're faced with a very short takeoff runway, you might just want to use manual throttle and stand on the brakes, while you get your RPM up. Then release the brakes and go.

Also, I generally don't try to use heavies at an airport with runways less than 10,000 ft. (unavoidable in some cases, like at Berlin)

-Seth

thanks Seth, but I think I recall being able to take off at around 180-190 knots. Isnt that the V1-V2 Rotate speed?? BTW, I never used flaps for take off, but will try it now with 15 degrees. For some reason I always thought that flaps on T/O would slow you down.

thanks again

Speedbird_1961

For some reason I always thought that flaps on T/O would slow you down.

They create drag and lift, also allowing you to fly at lower speeds

flaps on take off are set at 15 degrees or so, due to the fact it provides the required lift without causing any major slowdown.
is this the default, aircraft or one you downloaded? if its downloaded like was suggested there maybe a problem with the flight dynamics

Ok, great, thanks a lot guys/gals. BTW, I never fly default aircraft, only Meljet and Posky.  I have tried the Boeing 777 on a take off roll with 15 degree flaps and YES, it worked. I was indeed able to lift off at around 190 knots with a little runway left over. I suppose zero flaps and a full fuel load were the cause of the problem. I had thought there was a problem with the aircraft, but you guys sure have all the answers ,, again,, thanks

Speedbird_1961

Flaps basically allow the wing better performance at lower speeds.  

thanks Seth, but I think I recall being able to take off at around 180-190 knots. Isnt that the V1-V2 Rotate speed?? BTW, I never used flaps for take off, but will try it now with 15 degrees. For some reason I always thought that flaps on T/O would slow you down.

thanks again

Speedbird_1961

Just wanted to add a little something here, V1 is - as you probably know -  the take-off decision speed, and those numbers change depending on numerous variables such as fuel load, rway wind and total weight, of course!
V1 speed also decreases depending on your flap set-up.  :)
So in real life, there's really no way to pin-point a certain velocity as the v1 speed for an aircraft.