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Chris777
1st Aug 2007, 12:46
I am really interested to know how frequently take-offs are aborted on passenger jets?

I know there are no precise answers, but could you give me an idea of how many times this would happen in an airline pilot's career? I have never experienced this as a passenger.

What is the normal procedure? Does the captain simply call "ABORT"? And what happens if the captain is NOT the pilot flying? Does he still decide whether to go or abort? PS I'm familiar with V1 rules - no need to explain that.

Thanks so much for your answers.
Chris

HEATHROW DIRECTOR
1st Aug 2007, 13:19
Very rarely.. In 20+ years in Heathrow Tower I only saw a handful. Two of those were one aeroplane, which subsequently took off and I guess the pax were twitched up!

Chris777
1st Aug 2007, 14:30
Thanks very much for the interesting information, Rainboe.
I did not realise there was quite so much involved.

So it seems that aborted take-offs are a rarer phenomenon than go-arounds. Does this mean that things simply do not go wrong during the take-off roll, or is it rather the case that they are not sufficiently serious to warrant aborting the take-off?

Are these drills practised regularly in the simulator, given that pilots do not experience them regularly in real-life flying?

And just to be clear - if the F/O is flying, who calls the abort?

NudgingSteel
1st Aug 2007, 22:29
From a controller's viewpoint, we do see RTOs on a more regular basis than you'd expect. However, I've never witnessed one at anywhere near V1 - all the pilot-initiated ones have been from low speed at the start of the roll and seem to be, as power is applied, some sort of configuration warning. Often sorted out after a few minutes at the holding point but occasionally requiring a return to stand.
We're required to carry out a runway inspection after an RTO in case anything has dropped off (unless it is confirmed that it was due to a passenger standing up, or likewise). Not a great issue, apart from the inevitable delays occurring to the queue of departures waiting to get away....

Seloco
2nd Aug 2007, 07:46
As a pax I have had 3 t/o aborts in 20 years of intense international flying. All were pretty much non-events except for the hassles of waiting for brakes to cool or finding a replacement aircraft afterwards.:*

By coincidence I have also had 3 go-arounds and 3 en-route returns to base during the same period, so at least the statistics are consistent!

Maude Charlee
2nd Aug 2007, 10:14
I've had 4 rejected take-offs in 18 months. 3 at low speed just after take off power was set, and only 1 close to V1.

2 of the low speed rejects were for a caution light illuminating (AC Gen both times), and the 3rd was a "stop" instruction from tower due to FOD on the runway.

The high speed reject was for a possible bird strike (3 crows fighting on the runway and the skip thought they may have hit the no1 engine as we passed).

All complete non-events, but it seems I now need to get my average down somewhat. :}

BelArgUSA
2nd Aug 2007, 11:09
With 22,000 hrs now, since 1969... never aborted a takeoff near V1 speed.
I aborted a few times around 80 kts or so...
xxx
I had two engine failures right at VR speed...
xxx
One was in a 727-100... main gear tire nš 4 exploded at rotation, parts of tire were ingested in nš 3 engine (RH pod engine) and engine got torn off the fuselage, fell on the runway (we did not immediately know it fell on the runway until seconds later, when tower advised us)... The R/T sounded like this... "Frankfurt, Clipper 789, we lost nš 3 engine, request immediate return and vectors" - "Clipper 789, affirmative, you lost your engine, it is on runway, we will vector you to the other runway"... Definition of lost an engine, and "lost an engine"...?
xxx
The other was in a 747-200F, Lagos, Nigeria, also at rotation, flock of large birds decided to takeoff same time we did... (tower did clear us for takeoff, birds forgot to ask for takeoff clearance) - One, or a few hit the nš 4 engine, engine failure and fire warning, F/O was PF, I handled the check lists with F/E, airplane flew profile to acceleration and flap retraction. The problem was severe vibration of nš 4 engine windmilling, at speeds above 220/240 kts, shaking outer part of RH wing. So we re-selected flaps 5, and reduced speed to about 200 kts, and flew 45 minutes cruise, low level to Accra, Ghana, where we could get maintenance. Next day, aircraft eventually ferried on 3 engines to Luxembourg for engine change.
xxx
I suppose that Lagos restaurants had fried chicken (chicken?) on menu that day...
xxx
:)
Happy contrails

Chris777
2nd Aug 2007, 20:51
Thanks for the explanations guys.

Rainboe, I ask purely out of interest! Basically, although I have never experienced it first-hand, I think that from a passenger's point of view it comes as an enormous shock.

As for proximity to V1 when aborting, take a look at this video:

http://video.google.com/videoplay?docid=-7832043939212729970

It takes an eternity to download and the guy who's filmed it is a bit of a moron (ridiculous commentary), but the video itself is interesting. It looks like this aircraft was at V1 more or less when it aborted. Agree?

Can anyone envisage a situation in which you would abort just after V1? Or is that an absolute no-goer (so to speak)?

Chris

Doors to Automatic
3rd Aug 2007, 18:52
That is one amazing video. The abort occured approx 40 seconds into the take-off run so the aircraft would have been very close to V1.

Interesting to note that the plane only took 20 seconds to stop!

The power was cut exactly half-way along the runway and the aircraft took less than 3000ft to come to a complete stop. It is interesting to see just how quickly these planes can be brought to a halt if the need arises!

Maude Charlee
4th Aug 2007, 11:42
Yep, it's called adrenaline. :}

ComJam
4th Aug 2007, 12:32
So his guess of "V1" was wasn't V1 then....he's "one of them" isn't he :rolleyes:

Doors to Automatic
4th Aug 2007, 15:47
I reckon he would have been around 2-3 seconds from V1 when he chose to abort. Certainly no more than 5 seconds.

WHBM
7th Aug 2007, 13:27
Out of maybe 500 commercial flights I've had two RTOs, which I suspect is probably higher than the average.

One was apparently an airspeed indicator discrepancy (at maybe 60 kts), the other was after about 2 secs of rolling and probably was some configuration display issue.

Oh, and I've done one myself in a Cessna because my seatbelt was trapped outside the door and started flailing away. Won't do THAT again :uhoh:

Avman
7th Aug 2007, 22:58
A budding Sun reporter if you ask me! Would love to know out of curiosity what the real story was. Without getting into any debate about the actual speed, they were certainly going at a fair rate of knots at the time of the RTO.
Only had one in 1700 plus flights myself, in a Pan Am B747 at BRU back in the 70s - and that was at all of about 20 knots!

Doors to Automatic
8th Aug 2007, 11:50
"And you say he's near V1 because this idiot commentator said so?"

No I said it because he was fully laden and half way along the runway so he would have been close. (And I also have a fair idea what I'm talking about)

Would be great if we got some-one sensible's actual opinion on how close this was - just out of interest.

Farrell
8th Aug 2007, 14:10
Lion's Den is about to open up here methinks.

RingwaySam
9th Aug 2007, 11:00
Saw this video a few months back and started a discussion on JetPhotos about it. A guy that works for AC posted some details on what had happened...

"Fin 684, AC036 rejected take-off at 155 knots as the flight crew received an Eicas message advising them of "gear failure". They elected to abort the take-off. Four tires were blown during the stop. The acft was never in any danger. The inspection found that a "gear seal' had failed."

Now im no pilot but on a flight that I was on (767 / MAN-ACE) the pilot told us that we would rotate at 190mph, which is around 165knts. Surely the AC would have to depart abit faster with the flight being so long?

Chris777
18th Aug 2007, 13:31
Thanks for everyone's comments - really helpful and much appreciated.
I'll wrap this forum up now and if I feel the power cut and max brakes applied on take-off, I'll know not to panic.
Chris

The Otter's Pocket
21st Aug 2007, 19:23
What a tool.
The type of boring idiot who talks about your job to you and how he would liked to have been there, except it was the fault of his 2yr school teacher who failed himin PE. Sod Off you boring looser...

What ever happened to turning off electrical goods before take off and Landing?

V1? I thought the A/C was a Ryanair taxiing to the hold.
I have rejected higher speed take-offs in a Duchess...:}

Pilot_in_the_making
24th Aug 2007, 02:40
As an engineer, I've not yet had to deal with a commercial aircraft that has rejected take-off. I guess that commercial aircraft are maintained to fairly stringent standards in the UK, hence it is rare that anything goes wrong that is serious enough to warrent rejecting take-off.

I've seen three in light aircraft since I started flying a year ago:-

The first one was in a PA-28 taking off behind me. The pilot (from what I heard on the radio) forgot to secure the top latch on the door before take-off and the door popped open as the aircraft accelerated. Unfortunatly the PA-28 door isn't exactly Murphy proof (we all know Murphy's Law don't we?) :rolleyes:

Number two, Cessna 172, the pilot (my friend) reported partial electrical failure. He lost his primary radio, ADF, a VOR and the GPS as he opened up the power, shortly followed by everything else avionic because he had to turn off the master due to a slight burning smell as he taxied in. The smell turned out to be the bonfire next door and he over-reacted! :ooh:

The final one, another C172 we me at the left-hand seat, taking of from a remote private airfield in the middle of the countryside, a rambler with his dog thought the field was a public right of way and walked out into the middle of the runway. :ugh:

To answer your question, I guess RTO's are fairly rare in commercial aircraft, but more common in GA/light aircraft.

Doors to Automatic
15th Oct 2007, 11:08
155kts would be very close to V1 on a 767.

Also it is very easy to tell where the halfway point on the runway is as Japanese airports have white markings across the runway at its midpoint, which can be clearly seen in this video just at the point of the abort.

AnthonyGA
15th Oct 2007, 18:40
How do airlines deal with a pilot who goes around or aborts a take-off? I assume a go-around isn't much of big deal except for extra delay, but doesn't an aborted take-off potentially cost the airline a lot of money, particularly if brakes or tires are damaged?

Do airlines usually give pilots the benefit of the doubt and not hassle them about such things, or do they have to fill out a pile of paperwork and prove that they did the right thing, or what? Or is it simply a non-event from the airline's viewpoint?

moonbase
17th Oct 2007, 20:14
The airline I work for has a fairly reasonable no blame poilicy but the paperwar is still fairly large. The reason for the abort or the go - around is what is going to cause you more or less paperwork. If it is a standard go-around for traffic on the runway - no problems - if it is perhaps self induced such as an unstable approach or incorrect settings then it will generate an investigation so the paperwork will need to be carefully written - and prefferabvly with a self anaylsis of the situation.
The same for the RTO - if purely mechanical then then the paperwork will just process through the system - if for pilot error e.g. incorrect flap settings or configuration warnings then there is likely to be much further discussion and paper.:hmm:

barit1
17th May 2008, 20:16
I experienced one low-speed RTO probably 25 years ago in my jump-seat days. One engine failed to wind up as throttle was advanced. We cleared the RW and taxied back, turned on bleeds for the second attempt, and that did the trick.

Funny but the FE had the notion that bleeding the fuel line (solenoid controlled from the overhead panel) would clear the hangup. I had a long talk with him, explained that it was an aero problem in the compressor, not a fuel problem... :ugh:

JEM60
19th May 2008, 08:23
I would be VERY WORRIED if, as he says, they are at the Outer Marker, and they are turning at the threshold!!!!!!!!! I had 3 RTO's in a Brittania 100 series at Palermo, Sicily. These were on the one flight!!!!! Made it at the 4th attempt!!. No explanation offered. Thought this guy was a complete jerk who hardly knows his a...e from his elbow when it comes to flying. As a videoer of Airshows and aircraft,myself, anybody filming twelve minutes of ground stuff has too much time on his hands!!!.

creamegg
19th May 2008, 10:19
I assume V1 is the point of no return? :8

Batesy
21st May 2008, 14:39
You'd assume right.