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twilfert

How to perform a rejected take off

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Hello,

my question might sound a bit stupid but I could not find anything about this topic on the net.

After already in take off mode, I tried to reject the take off by just pulling back the throttles at my joystick but the aircraft continued to accelerate for take off.

What do I need to do to reject the take off?

I would be very thankful if you could help me here.

 

Thanks very much in advance.

 

Tilo

 

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What do I need to do to reject the take off?

 

Ensure your A/T setting in the PMDG SETUP menus is set to allow the hardware to override in HOLD/ARM MODE.  Sounds like the sim is just ignoring your hardware.

 

The steps for rejecting throttle are as follows:

  1. Pull throttles back to idle
  2. Done

(Provided your autobrake is set to RTO)


Kyle Rodgers

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Thanks so much. The A/T setting in the PMDG Setup menu was exactly the missing item. It works now:)

 

Kind regards,

Tilo

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The steps for rejecting throttle are as follows:
Pull throttles back to idle
Done
(Provided your autobrake is set to RTO)
Idle, or reverse? I realize if you have lost an engine you probably don't want that one in reverse in case it makes things worse.

 

In this vid they use REV even though something went wrong in Number 2 Engine

https://www.youtube.com/watch?v=PS1YAX70edc

 

In this vid they don't - although it is at Airbus plant so possibly during testing they may have not used it.

https://www.youtube.com/watch?v=sn7JHwRPKf4#t=68

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Additional comments:

 

Your speed at the time you decide to reject the take off, *must* be less than V1 (you probably already know this).

 

I would also use reverse thrust (if both engines are running normally) to help me stop the airplane.

 

I would ensure the speed brakes were deployed (up) and if for some reason they were not, I'd manually extend them immediately.

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Idle, or reverse? I realize if you have lost an engine you probably don't want that one in reverse in case it makes things worse.

 

In this vid they use REV even though something went wrong in Number 2 Engine

https://www.youtube.com/watch?v=PS1YAX70edc

 

In this vid they don't - although it is at Airbus plant so possibly during testing they may have not used it.

https://www.youtube.com/watch?v=sn7JHwRPKf4#t=68

 

In the DC-10 we taught throttles idle, max reverse, max braking, ensure ground spoilers deployed and slight forward pressure on the yoke. In the Gulfstream its basically the same. It's briefed, idle-reverse-brakes-brakes(speed brakes). Reversers are as required control permitting. If its a dry runway, I'll use max reverse engine out. If it's wet, I'll meter the reverse based on controllability. If it's icy, I'll use reverse idle. The use of reverse all depends on conditions and the reason you aborted. With icy and high crosswind conditions, reversers may aggravate the situation. During takeoff, many manufactures factor in the use of engine out reverse for accel stop distances. 

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>During takeoff, many manufactures factor in the use of engine out reverse for accel stop distances.

 

For US certification, the FAA does not allow the use reverse thrust to measure take off / stop distances. Thus, the takeoff / stop distances have a built-in safety factor because the customer flight crews will be using reverse thrust, in most cases, when they abort a take off.

 

When ever you watch the test pilots do the rejected take off testing, it's always the same, and has always been the same for many decades now, even when Lockheed and McDonnell Douglas were in the business: they load the plane to its max take off weight, make sure the brakes are well worn (not new brake pads), start the take off roll, at V1 the pilot aborts the Take off and ensure the spoilers are deployed but the pilot cannot use reverse thrust.

 

Max braking is applied and you can see the brakes turn red/white hot...the plane finally comes to a stop and must sit for 5 mins, and the fire that starts (and one usually does from the brake material) around the main gear must not reach a major structural part during that 5 min period...and if all of that happens as planned...they pass!!

 

Here is the B-777 RTO test:

 

And here is the B-747 RTO test:

http://www.boeingblogs.com/randy/archives/2011/05/back_when_i_first_started.html

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For US certification, the FAA does not allow the use reverse thrust to measure take off / stop distances.

I am in the U.S., when I flew DC-10s we would have to use reverse inop charts when one was locked out in order to calculate speeds, distances and max weight charts. This is why i made the statement. Here is a chart from my DC10 manual. Even the G550 has corrections on wet runways with a reverser locked out though it has a JAA cert.

reverse_correction.jpg

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I think your use of the word 'manufactures' threw me for a loop...you're really talking about 'operators' having and using take off distance charts with and without the use of reverser's. That makes sense.

 

Take off and stopping distances the manufacturers measure without the use of reverse thrust are for certification only.

 

:lol:

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I think your use of the word 'manufactures' threw me for a loop...you're really talking about 'operators' having and using take off distance charts with and without the use of reverser's. That makes sense.

 

Take off and stopping distances the manufacturers measure without the use of reverse thrust are for certification only.

 

:lol:

During flight testing, all of this data is collected for the purpose of creating the performance manual. The manufacturer will then deliver with the basic performance data. The operator can purchase more advanced performance data from the manufacturer for a fee. You can purchase it tabular or charted. If you think having a FAA approved performance manual containing data with and without reversers is strange, have a look at my reverser only landing distance for the G5/550. It's from the QRH. At max landing weight at SL, I can stop in 6200ft using reversers only without touching the brakes. This is great info when landing in icy conditions.

GVreverse.jpg

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Idle, or reverse? I realize if you have lost an engine you probably don't want that one in reverse in case it makes things worse.

 

In this vid they use REV even though something went wrong in Number 2 Engine

https://www.youtube.com/watch?v=PS1YAX70edc

 

In this vid they don't - although it is at Airbus plant so possibly during testing they may have not used it.

https://www.youtube.com/watch?v=sn7JHwRPKf4#t=68

In the context of this thread idle is sufficient to put the brakes in RTO mode.

ki9cAAb.jpg

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kevinh, on 27 Sept 2014 - 9:34 PM, said:

In the context of this thread idle is sufficient to put the brakes in RTO mode.

In the context of this thread, which is "how to perform a rejected takeoff" I was interested to know what the normal technique was, and really hope that if I am on an airliner that rejects the takeoff, the pilots don't think that simply reducing to idle to activate RTO autobrake is "sufficient"... I would prefer they use every last bit of negative acceleration available to them, including reverse thrust.

 

If it was the normal, airline and OEM approved, method.

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