Abort Take-Off

[DeanNufcEmre]

Hey guys, just want to ask a quick Q

When your speeding up down the runway on a take off, and you want to abort it for some reason (engine power difference etc), what do
you do?? I know obviously stop and break etc, but how can you register this is FSP??

Whenever i have done it, it just says you failed to land at the scheduled airport etc

Any help?? Thanks

[dannyboy2005]

Just don't take off, As long as nose gear donsn't leave the ground. Slam reversers on, spoilers then Max break. Taxi to the taxiway and fix the problem then start again. I've had to do this
many times.



Post Edited ( 06-03-07 00:06 )

[Anastasios]

For FsP to recognize the RTO you need to accelerate to at least 60 knots I believe. If you abort take off after 60 knots, then FsP will
recognize it.

Anastasios.

[Jambone]

They should make it so that the limit is extended to 120 (V1) for the bigger jets

[Anastasios]

No, because you can actually have an aborted take-off already during taxiing....

Anastasios.

[Jambone]

Actually, they should have an option to report "aborted takeoff"

[dannyboy2005]

Jambone wrote:
Actually, they should have an option to report "aborted takeoff"

I agree.

[DeanNufcEmre]

I also agree^^

Thaks for the info guys!!

[Jambone]

WOW! a newcastle fan! Im one to not sure about emre tho lol

[Ceemosp]

As long as nose gear donsn't leave the ground

WOW, what a blunt and wrong statement
I wonder that nobody said anything - good that I'm back

I don't know about you but I have heard rumours about so called V-speeds

V1 - Speed from which onwards the runway length is not sufficient to abort take-off anymore.
Vr - Rotation speed (nose lift's off the ground)
V2 - The speed the plane needs to become airborne (wings generate enough lift)

All these speeds are very dependent on various factors, such as weight, airport altitude, temperature and runway condition(contamination, surface etc).

Now, unless the V1 speed is HIGHER than the Vr speed (or V2), the Vr speed is completely irrelevant to the question of when to abort.

slam the reversers in

Another one of those very general 'good advices' that you can not give.
It very much depends on the cause for the aborted take-off and to a degree also to the aircraft type.
Let's say one of your engines just went tits up. You fly a 747 or a plane with rear mounted engines (MD-80, Challenger) on a calm day and there is not much harm to it doing so.
You try that stunt on a 37 with wet runway, sidewind gusts from the wrong corner (the one from the dead engine) and you can find yourself in all kind of doo-doo trying to keep the plane on the runway.
regards
Carsten
Team 68301 - Derek's Wish



Post Edited ( 06-06-07 19:55 )

[poden]

Yup, aborting a takeoff is a very tricky thing. Here's a page on "V1", which I understand to be the abort speed as well:

http://www.aeromech.usyd.edu.au/aero/perf/to/

Now, COMPUTING an exact V1 for the aircraft weight, availability of brakes/reversers, runway length, airport altitude, temperature, all that, is pretty tricky. But generally you rely on a table for V1 (i.e. the FMS "looks it up" based on a number of factors).





Post Edited ( 06-06-07 21:20 )

[Ceemosp]

as said...anything beyond V1 and it will most likely be a nice overshoot. It's pretty much like the safety distance with cars. A given distance is
just sufficient to stop a car up to a certain speed.
Whereas a crash with a car is one thing (given you survive the three-million airbags going off around you), running with a plane full of fuel into
anything, deems not to be advisable at all

That thrust reverser thinggy is also interesting. On a 747 you will just use the reversers on the two live engines in two combinations 1+4 or 2+3. I
suppose you need some good brakes on shorter runways as you would come in slightly faster anyhow (to give you more room if something doesn't fit and
you have to go around). I bet the Connie pilots were brilliant with 3 engined landings, as it's rumored to be the best tri-motor ever built

Carsten

[upsidedown]

Ceemosp said

"V2 - The speed the plane needs to become airborne (wings generate enough lift)"


Just wanted to point out that V2 is the take off safety speed. This speed must be reached by 35ft AGL
By definition the A/C has already reached a speed at which the wings will generate sufficient lift by VR other wise you would not be
rotating.
The take off safety speed is a safe climb speed such that the A/C will continue to climb in the event of an engine failure. Single engine
A/C do not have a V2.

Hope that clears it up

[Ceemosp]

Good point and badly phrase by me

I over-simplified the explanation. You are totally correct about the 35ft Now that you started to explain, let's go the full nine yards

Let's have a look what the books say:

V2 - the minimum safe speed in the second segment of a climb following an engine failure. Also called takeoff screen speed and sometimes, takeoff
safety speed, although as the second climb segment indicates, V2 is an after takeoff speed frequently achieved shortly after rotate (Vr) as the
aircraft accelerates. The engine failure case that is taken in the calculation of V2 is that of the "most adverse engine" because the effects of
different engines when failed, differ. The calculation of V2 also includes set margins over the stall and other safety factors are built in as well.

So i SHOULD have said - the speed an aircraft will become and REMAIN airborne in case of an engine failure.

As a single engine plane can't continue the takeoff with an INOP engine - logically there can't be no V2 speed for them.

VR - rotation speed. The speed of an aircraft at which the pilot initiates rotation to obtain the scheduled takeoff performance.

The ability to rotate an aircraft does NOT automatically imply you have enough lift for climbout. This is only generated by the increased acceleration
and the now different AoA.
This is nicely demonstrated in the over-rotation tests, when the plane's nose gets raised to the point where the tail hits the ground and is then
dragged along the runway until the aircraft becomes airborne.

Rotation and climb-out speeds are two pair of shoes.

I think we now have this lined out entirely

http://adg.stanford.edu/aa241/performance/FAR105.html <- for those really wanting to get lost


regards
Carsten
Team 68301 - Derek's Wish