Would you abort after V1?

[ssg]

Here's a guy that decided to go...flat tire...Guppy...you there?

Congo plane crashes at end of runway; 85 aboard
Charles Ntirycha / Associated Press
GOMA, Congo -- A Congolese jetliner carrying around 85 people failed to take off Tuesday from an airport in this eastern town, crashing at high speed into a busy market neighborhood at the end of the runway, officials said.

Government officials initially said there were only six known survivors but later in the day an airline official said 60 people had survived. Local officials said dozens of bodies were pulled from the wreckage, though it was unclear if they had been passengers.

Smoke and flames engulfed the charred ruins of the aircraft, which appeared to have broken in two when it slammed into the rooftops of about 10 cement homes just outside the airport, destroying them instantly. Soldiers kept onlookers away after U.N. peacekeepers helped douse flames at the crash site.

"Smoke was rising from the plane," said Christian Kilundu, a spokesman for the Goma office of World Vision, an international aid group that has an office less than half a mile from the crash site. "As fire extinguishers were trying to put out the flames, I spoke to a priest who had been pulled from the wreckage. He was disorientated and had no idea what had happened."

Officials said they had no information on casualties among residents of the area.

The plane was operated by the private Congolese company, Hewa Bora, and was headed to the central city of Kisangani, then the capital, Kinshasa. Hewa Bora's Dirk Cramers said 53 passengers and seven crew were taken from the site and were at local hospitals.

Julien Mpaluku, the governor of the province, said there were 79 passengers on board and six crew members.

"We have already picked up many bodies -- dozens of bodies. There are a lot of flames, which makes it difficult to know if the bodies we are picking up are those of passengers of the plane or else passers-by or people that lived in the area where the plane crashed," Mpaluku said.

Employees at World Vision said the plane "failed to leave the ground," plowing instead "through wooden houses and shops in the highly populated Birere market."

The plane appeared to have been "totally flattened" by the impact, said Rachel Wolff, a U.S.-based spokeswoman for the organization who has been in contact with her colleagues in Congo.

World Vision employees who visited the scene of the crash said they saw at least eight bodies. Hours afterward, the market stalls where women had been selling their wares earlier in the day were still in flames, said Wolff.

A former pilot who survived the crash, Dunia Sindani, gave a similar account in an interview broadcast over a local U.N. radio station. The plane suffered a problem in one of its wheels -- possibly a flat tire -- and did not gain the strength to lift off, Sindani said.

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Just fly it to the fence and go...right Guppy?

[tttoon]

V1:

Maximum speed during takeoff at which a pilot must first make an action to stop the aircraft within the accelerate-stop distance. May also mean the minimum takeoff speed that will allow the pilot to continue the takeoff after failure of a critical engine.

So what exacty is here that you do not understand? Can't you see that trying to stop an aeroplane after this speed is extremely dangerous, and that if you start bending the rules to your specific (perceived) situation may be dangerous? V1 is the speed where it is generally safer to fly, and if everyone started to ignore this there will be a whole lot accidents that don't happen now.

also, FYI, when you think the whole world is against you, think about why that could be instead of digging in further.

[Ollie268]

briefings and training are there for a reason, if you brief to go after v1, you go unless you physically cannot due to control restriction...etc.
If you brief something and do the opposite well then you are single pilot in a multi crew environment, the other guy is out of the loop and wont know what your doing - much more riskier than flying as briefed and dealing with it in the air.

[Cap Loko]

ssg,

Interesting but obvious tread. To answer your question: yes, after V1 i would go even with 'plenty' of runway left, no doubts here..

Also having your other statements in mind regarding the so called 'late rotations', keep in mind that there are things such as stopways and clearways. In Europe (just as an example), the max clearway is 1/2 of the flare distance of the a/c concerned. That may add to the effect of watching an aircraft rotating 'late'.

Have you ever had a look in the TOSTA (Takeoff Safety Training Aid)? It also includes statistical data about high speed aborts.

regards,
Loko

ps. Sir, was it proven that the plane in the Congo crashed because of a flat tyre? If so, it would be interesting to know why it couldn't liftoff just because of a flat tire.

[Pace]

There was an aircraft that took off from Leeds a few years ago, cannot remember the details that well but they had a severe fire. The pilot put it back down on the runway. The fire was so intense that had he attempted to do a circuit everyone would have perished.

There was an airliner which crashed on fire in Canada because the Captain insisted on flying by the book. Once established on the ILS he aborted the landing to dump fuel 20 miles away. The first officer pleaded with him to land overweight, he ignored the first officer and everyone perished.

I fly Citations and at a runway like Heathrow where I can takeoff three times with a severe fire problem I would put it back down.

Taking V1 ? if V1 is 100 kts does that mean you abort at 99 kts but take off at 101 kts are we all computers without brains and instincts? Some Situations demand that you throw the book away and become a pilot.

pace

[Caudillo]

Pace are you really suggesting we tell the computers what to do rather than the other way round?

Cowboy.

[Human Factor]

I would stop after V1 for two reasons and two reasons only:

1) Total engine failure (no choice)

2) Unable to rotate, for example a jammed elevator (ditto)

Either situation is extremely unlikely. V1 isn't always calculated as a result of remaining runway distance. Think also in terms of brake energy or max tyre speed for example.

[Pace]

No :-) but I am saying there are situations where we do not act like computers which are programmed not to think?

A guy I know well recently crash landed a citation up at Edinburgh. He had severe control problems and landed on the disused runway. His touchdown speed was 210kts. He stopped before the end of the runway and didnt burst any tires.

Pace

[Human Factor]

His touchdown speed was 210kts. He stopped before the end of the runway and didnt busrt any tires.

Well done, that man. I'd have been interested to hear the outcome if he'd tried to stop from 150kts two-thirds of the way down the same runway.

[mini-jumbo]

His touchdown speed was 210kts. He stopped before the end of the runway and didnt busrt any tires.

Congratulation to that man. I thought this thread was about takeoff, not landing.

[Pace]

He would have gone off the end of the runway. A few years ago I was flying a nearly new Seneca five twin and had an engine failure at 200 feet after takeoff.

Three rocker shafts had sheared off due to overtorquing at manufacture.
The aircraft was at Grosse weight temps were above standard.
My training dictated that I shut down the engine and feather the prop.

The engine was still producing maybe 30% power. I instintively knew by the feel of the aircraft that if I lost that 30% power I was going down.
Although there was severe vibration I kept the thing going with one hand on the prop ready to feather if there was a loud bang.

Once up at 1000 feet with some air below I made a gentle turn and then shut the engine down.

Going by the book is not always in every circumstance the best way. I admit in a heavy airliner tolerances are smaller and power is greater so your options are more to the book but that isnt always the case.

Pace

[Pace]

>Congratulation to that man. I thought this thread was about takeoff, not landing.<

Yes but the arguement placed here is that a few kts over V1 will dramatically increase your stopping distance. This guy landed near the start of the runway but at twice V1 if you like and he had no choice.

Pace

[SNS3Guppy]

Come on Guppy...don't give it away....

So the consensus is?

Flying a burning aircraft up through the soup, fighting the fire while in the circut for single engine approach is more acceptable then simply pulling back the levers and adding some brakes.?

A high speed rejected takeoff isn't nearly as simple as "pulling back the levers and adding some brakes." For a guy who claims to be dual rated, and have "10,600 hours and 7 type ratings" you sound for all the world in your posts like an individual who has never flown more than microsoft flight simulator.

These type ratings you claim...never obtained through FSI or Simuflite? Certainly they don't teach what you're espousing. Nor does anyone agree with it. And it sounds ridiculous.

Never the less, you keep pounding out this agenda. Now you've introduced the DC-9 crash in Goma, Congo. Your article was filled with emotion and all the things that are entirely irrelevant to a serious technical discussion...but nothing of substance to add to the discussion. Let's add some then.

What you conveniently left out is that the runway is very poor condition, severely damaged by a volcano six years ago, and still not fixed. The runway is 6,500 feet long now. The runway was wet. It's surrounded by high terrain; the VOR approach involves a six thousand foot descent from overhead the VOR on the field. The crew executed a rejected takeoff on that runway, overrunning the end and causing carnage.

So you ask...

Just fly it to the fence and go...right Guppy?

Clearly rejecting the takeoff didn't do much good; 37 so far dead. However, to discuss the merits further is pointless until more details emerge. What you managed to do was inject more superfluous information which you appear to have dredged off a news report...offering nothing meaningful but drama. You do this just to cloud the issue? We don't have any useful information regarding why they did what they did, at what point in the takeoff they did it, or if they made a good decision...nothing...yet this is the evidence of your flawed case? Moreover, you're using African aviation as an example of what to do or not to do??? This is the fifth fatal crash in the Congo in the last year, and they've been banned from operating to Europe. Hardly the model example of what to do, and hardly a useful example in light of the fact that no details are presented.

'Great Spirits have always enountered violent opposition from mediocre minds."

You reckon you're a great spirit, do you? Okay, great spirit. Throw out some real world numbers. A good start will be all the successful high speed rejected takeoffs above V1 as a good faith effort to show that what you're talking about has at least a track record of success. When you're done with that, educate yourself a little bit on what really happens during a high speed rejected takeoff, and the reason that universally everyone disagrees with you. You might learn something (though it's doubtful, based on your comments here). Instead of pulling ridiculous, dramatic, irrelevant examples out of thin air, why not stick to the meat of the matter? Better yet, drop it. Your horse has been beaten dead.

[mini-jumbo]

Yes, but the point being he was landing at the beginning of the runway. So, if he was unable to stop, due to his fast approach speed, the overrun would have been at very low speed.

[NigelOnDraft]

Maximum speed during takeoff at which a pilot must first make an action to stop the aircraft within the accelerate-stop distance. May also mean the minimum takeoff speed that will allow the pilot to continue the takeoff after failure of a critical engine.

This quote is the "key" The answer depends on whether the V1 you have is "go V1", or a "Stop V1". Traditionally, and in the majority of the posts above, a "Stop V1" is assumed i.e. a reject > V1 almost guarantees an overrun which is v dangerous.

However, frequently "we" fly to a "go V1" e.g. a light A319 off LHR with a V1 of 115K You could get off LHR, climb to 300', then land back on and stop The problem is you rarely know what type of V1 you have, and even if you did, how far beyond it you can go before it becomes the other type of V1

So in round terms you have to treat it as a "go V1", and even in the scenario above, I will "go" for an engine failure > 115K with 10,000'+ remaining - that is the only "correct" action. But, in a complex / multi failure situation, a "stop" might be called for, that is what "judgement" is, and what we are paid for. NB it is not "incorrect" to reject > V1, just the circumstances in which it is warranted are not defined

NoD

[Artie Fufkin]

Agree with NoD that in some circumstances you could reject and stop safely above your bugged V1. (Bugged V1 is Vmcg, but high range V1 is coincidental with Vr)

In a B737/A320 type operation with typically less than 2 or 3 seconds between V1 and Vr, do we realistically have the time and/or capacity to make a judgment call of the magnitude of rejecting above V1? I was always told if anything goes wrong, sit on your hands and then calmly decide what to do. In circumstances where this is inappropriate and instantaneous reactions are required, we have well drilled and practiced memory items to be followed to ensure the safest outcome. The definitive example would surely be an engine fire between V1 and V2!

At the company I work for, we use low range V1s on the principle that statistically less accidents have occurred by continuing the take off when compared to high speed rejects.

[ssg]

Very Interesting..

Pace was the only one who agreed with me, he flies Citations too..I wonder if the airlines train different then corporate. Pace, I wouldn't fly a wreck into the air either, but the airline guys in here think that's a great idea...

I never felt the pressure in the Sim to go when I had a ton of runway to stop, if right after V1 something happened.....the goal was that I made a decision that kept the plane intact and kept people alive.

We all remember that right?...to keep the passengers alive?...right guppy?

Well you don't see too many crashed corporate jets that tried to go now do you...You tube is full of airliners that tried to make it though..

Hey, whatever guppy...yeah been to Simuflite Dallas 9 times, Flightsafety 4...

If You wanna fly a burning aircraft into the air when you coulda stopped, good for you...

As far as this BS about rejected take offs being dangerous it seems that the guys that roll off the end of the runway seem to walk away, it's the guys that try to fly the plane off and crash, tend to kill everyone on board....

[Denti]

Nowadays it is nearly impossible to have too much runway in front of you at V1, at least in the airline business. I have no idea if it is usual to reduce your thrust on GA aircraft with the same tools on a regular basis as we do in the airline business.

Even in a nearly empty 737-700 we have a Vr in the red lights on a 4000m runway, but we usually use improved climb, fixed derate and assumed temperature, it saves millions over the course of a normal year even on a small fleet.

If i can really do a reject precisely at V1, the best i could do was a stop 180 ft short of the end of the runway, but only if i have both engines and use full reverse which is not part of the approved performance figures. Just missing a "small" item like raising the speedbrakes will certainly lead to leaving the end of the runway at 70kts, not a nice thing to do. Just waiting until 2 seconds after V1 with the start of the RTO manouver will lead to the same result. Even more interesting, a blown tire but otherwise a perfectly executed RTO with 2 engines running and full reverse thrust will still lead to leaving the runway at 45kts.

And yes, using the wrong numbers like dry performance on a wet runway is very unpleasant as well. Real engine failure close to V1 and perfectly executed RTO with reverse thrust at dry V1 on a wet runway will lead to leaving the runway at 65 kts.

Those figures are very sobering and that is why we are trained to be go-minded and have to watch boeing/airbus instructional videos at least once a year stressing that point.

When comparing airline and business accident figures you have to count in the difference in numbers of sectors/hours flown per year and aircraft as well as total figures. For example a normal (longrange) aircraft in our fleet flies around 6000 hours a year and there is still space to improve that, though not by a lot.

[ssg]

hmmmm.

Denti...question...

Why can't you take off max thrust vs reduced...which seems less safe...

Do you set your reduced thrust to just make the balanced field requirements?

In GA we do max thrust...if we can't make balanced field, we change flaps, reduce fuel, find a longer runway, leave at a cooler time...ect...

It's pretty common though on a rediculously long runway I might not try to get that last 2% out of the engines and fiddle with the levers, just don't need it...

[mutt]

ssg, you might be surprised to hear that our B777's operate at an avarage of 80% of takeoff power based on annual statistics, we can combine two forms of reduced thrust so that an individual takeoff can be conducted at approximately 55% of takeoff power on a light aircraft.

It all has to do with keeping the engine cool and prolonging its life.

Mutt