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High Altitude Takeoffs

PostPosted: Sun Feb 19, 2006 5:18 am
by globetrekker2k2
I'm about to do a flight from El Alto, in South America, to Panama and all yesterday I had a big problem with acceleration because the airport is above 13000 ft. I'm flying in an A320. Is there a certain method I should try

Re: High Altitude Takeoffs

PostPosted: Sun Feb 19, 2006 5:26 am
by madness
i think i got the anwser, how early in the run way did you pull up?

i

Re: High Altitude Takeoffs

PostPosted: Sun Feb 19, 2006 6:26 am
by Delta_
The thrust the engines produce is proportional to the density of air, at higher altitudes the density of the air is significantly less.  This means you can not accelerate as fast.  You need to allow a longer take-off distance on the runway, or reduce the payload so you are lighter. ;)

Re: High Altitude Takeoffs

PostPosted: Sun Feb 19, 2006 7:41 am
by Fozzer
When taking off at high altitudes in my General Aviation, small piston props, I have to weaken the mixture to obtain more power for take-off and climb...
...air to fuel ratio...;)...!
(You normally have to weaken the mixture when over 5,000 feet ASL in any case, on all piston props, (especially those fitted with carburettors), to obtain the maximum power).

Paul.... 8)...!

Re: High Altitude Takeoffs

PostPosted: Sun Feb 19, 2006 9:11 am
by ashaman
Use the longest runway, don't overload the plane, in taking off allow as full the throttle as you can without blowing the engines and rotate gently at about 160 Kias with flaps 25 degrees or more.

It may seem a little too overboard for a 320, but given the altitude you're taking off from and its effects on both thrust and wing lift, you'll have to make due. :P

Re: High Altitude Takeoffs

PostPosted: Sun Feb 19, 2006 11:48 am
by vololiberista
Hi
If you want to do high altitude take offs
Use a Vickers VC10!!!
:)
Vololiberista

Re: High Altitude Takeoffs

PostPosted: Sun Feb 19, 2006 3:16 pm
by globetrekker2k2
about how far is the maximum i should try pushing the throttle to before I know I gave it too much

Re: High Altitude Takeoffs

PostPosted: Sun Feb 19, 2006 3:21 pm
by beefhole
about how far is the maximum i should try pushing the throttle to before I know I gave it too much

Generally, the maximum thrust you should give an aircraft, ever, is about 103% N1. (roughly) If that doesn't do it, you can consider pushing it closer to maximum available thrust.  In RL, something would turn red if you gave it too much-in FS with addon planes, you never know (my 752's EGT/EPR goes red whenever I give it takeoff thrust)

And I would advise against using 25 flaps-maybe Airbuses are different, but I know for sure that at least on a Boeing it would do far more harm than good.  Maximum takeoff flaps are generally 15.

Re: High Altitude Takeoffs

PostPosted: Sun Feb 19, 2006 6:19 pm
by ashaman
And I would advise against using 25 flaps-maybe Airbuses are different, but I know for sure that at least on a Boeing it would do far more harm than good.  Maximum takeoff flaps are generally 15.


Normally I would advise against it myself, but here we're trying to take off from a 13000 feet high runway, a little more flaps might be necessary.