Committing an airplane for take off?

Question

Hi
I have been watching a lot of air crash investigations, and would like to know what it means when they say that an airline is committed to take off? Why can't they stop the plane before they take off? This happened with Concorde in France where it was on fire before it became airborne, but the pilot had to take off to land?

I know I am sounding really thick, but if they did put all the brakes they had, wouldn't overshooting the runway into a field, if there was one, better, as I am assuming that more people would survive if they did not have to fall out the sky?

Answer 1

They're already going too fast to stop without running out of runway.

Answer 2

The point of decision is called 'vee 1'.
It all depends n the jet involved and the runway and running weights.
It doesnt mean the pilot can stop neatly on the runway at that point, it means its the last point at which it would be preferable to overshoot into the fields beyond.
If you hit the dirt too fast you will plough the nose in and go **** over tit. No-one would survive.
At least if you can get into the air you might be able to either slow and ditch or go around.

In the case of Concorde the pilot didnt realise how extensive the problem was. He crashed because he got no response from his controls as the fire took hold.

In the end it comes down to the thought process behind the captain decisions. I would try to stay on the ground as long as I could though.

Answer 3

An aircraft is committed to take off when it's speed on the runway is so high that it cannot stop within the remaining length of the tarmac. If an aeroplane runs off the end when travelling at high speed (usually at least 200mph) then an unsurviable disaster is almost inevitable. Even if there were no obstructions (and there always are) it would take a mile or so for the bits to come to a halt.

In an emergency after that speed is reached it is often safer to complete the take off and then fly around and attempt to land with the full length of runway and emergency services available on the airfield itself.

Incidentally, it's spelt aeroplane in English, not airplane - that is the variant used in the American dialect. (close, but it's not really the same language any more).

Answer 4

Every aircraft has what is known as an Accelerate and Stop Distance. This is where an aircraft gets up to rotation speed or take off speed, and rejects the take off and brakes to full stop. This is a calculated distance and the pilot must know if the runway is long enough in case of emergency.
Once an aircraft passes that distance they are committed to take off.
In the case of the Concorde they probably wanted to do a go around and land because it was deemed safer than aborting and going off of the runway. When you are reaching speeds required for take off you have literally a split second to make a decision.
Contrary to the above answers, when your plane is on fire, weight doesn't matter.

Answer 5

The problem with the concord crash was that the crew didn't know how bad things were. It is possible that running off the end of the runway at speed might have been a better option in this case. However if the aircraft can fly there is the thought that it's better to get it into the air and then select the landing spot.

Answer 6

this means the speed the aircraft is going at (v1) is now too fast to ever stop safely on the rest of the runway,its a calculation that's made before every flight,regarding runway length,a/c weight etc,the Concorde accident happened at,or just after v1,so the pilot then had to rotate the aircraft for lift off and take the problem into the air,pilots are tought this procedure.it was very unfortunate about Concorde and the way the accident occurred,its a type of accident that may never happen again,unfortunate circumstances

Answer 7

Two main reasons, If the aircraft was above a certain groundspeed then it would have to take off to avoid running off of the end of the runway (that's not always into a field, many runways are in the middle of cities or on the edge of rivers/lakes, causing all sorts of complications).

Also, if the fuel tanks are full (which they will be on take-off) then it's too dangerous as the fuel could leak during a crash (which is technically what it would be if it went off the end of the runway) causing a serious safety hazard (and potentially a fire/bigger fire). The aircraft has to take off, then jettison it's fuel in flight, then land. (It's also too heavy to land on a full tank, so it would need to be jettisoned!)

Hope this helps

Answer 8

committed for take off means you have reached a point on the runway where an aborted take off would result in an overshoot. To you follow up. Remember at take off the plane is at its heaviest with the biggest fuel load. skidding to a stop in an area past the runway may be OK, but there are too many variables and when we talk about airplanes being committed for take off we usually talk about transport category airplanes with 2 or more engines and it is usually safer to continue and return for landing than taking an airliner off roading.

Answer 9

Because a plane needs the entire length of the runway in which to stop. When taking off with a full load of petrol (TONS of it) travelling at 180 miles an hour in order to get this weight off the ground, you cannot then simply stop and put the brakes on as with a family car!

You are committed to taking off - you HAVE to. There is no other thing to do at that point.

Answer 10

When a plane starts of down the runway the pilot will say the following "V1, V2, Rotate" V1 is the speed at which they can stop the aircraft. V2 is the speed at which they cannot stop the plane on the ground. Rotate is when there speed is fast enough to take off.
Aircraft when they take of are actually heavier than the maximum safe landing weight with fuel. As a result if the plane was to land in a fully laden state the brakes/undercarriage would be seriously damaged or even fail under the stress of landing.
To overcome this the pilots would need to dump fuel o lower the overall weigh of the plane.
The main problem with concord was that after hitting V2 the aircraft needed a considerable length of run way before hitting the take of speed. So even if the pilot realized that the plane was in trouble he was unable to stop the plane on the run way. He would have slid of the end of the run way at over 100mps fully laden with fuel.
Unfortunately when a plane hits V2 the pilot has no choice he must take off.

Answer 11

When the PIC,(Pilot In Command) is commencing his take-off, they will keep one hand on the throttle column, and one hand on the yoke. This is so that if anything occurs to abort the T/O, they will have "hands on command" of the engines. When the F/O calls "V1", the pilot will now grasp the yoke with both hands, as the commitment to flying the aircraft has been made.

V1 is the minimum speed in the takeoff, following a failure of the critical engine at which the pilot can continue the takeoff with only the remaining engines. Any problems after V1 are treated as in-flight emergencies.

In the case of a balanced field takeoff, V1 is the maximum speed in the takeoff at which the pilot must take the first action (e.g., apply brakes, reduce thrust, deploy speed brakes) to stop the aircraft within the accelerate-stop distance and the minimum speed at which the takeoff can be continued and achieve the required height above the takeoff surface within the takeoff distance. In this context, V1 is the takeoff decision speed.