Perseverando88

You are flying your A-320 as a Capt. on your A-320.
The weather is 25 knots from 30 degrees off the runway. Overcast 200 with light rain. You are close to your max weight.

5 KNOTS PRIOR TO V1 : TIRE FAILURE

The best is to continue as Airbus recommends but not so easy in practise.

I remember a Canadian Airlines DC-10 had one just at V1 they aborted and went off the runway.


How does one identify a tire failure with the certainty to continue a take off. Yes a loud bang but there are other loud bangs which could mean other things such as an engine stall.

What is it actually like a tire failure ? As I have not had one. Then we would leave the gear down.

Cheers

AlR

Simple concept here. Tire blown or not by the time you recognize and react when you are V1 -5kts, you more than likely have already exceeded V1. Other concerns may be if you abort the braking efectiveness is reduced due to the blown tire (tyre), however the wing at that speed is producing enough lift to get you safely airborne. If all engines norm, you can leave the gear down for the circut.

Landing at a decreasing airspeed with all the runway infront of you with ARFF standing by makes a lot more sense than trying to abort with decreased braking and minimal runway in front of you.

Don't get to caught up in abnormals on T/O. Loss of control, ENG Failure, fire-smoke in A/C are couple to really consider. But most abnormals can standby for a circut and landing.

Bottom line...if the Aircraft can safely make another circut and landing, don't abort near V1 .

nugpot

I completely agree with you in principle AlR, but in practice it becomes a bit of a grey area.

At what speed would you abort then? V1 - 10, V1 - 15? There must be a speed at which you would abort. If so, what use is V1?

In my company, a standard briefing includes something like this: "Before V1, we will abort for any caution, warning or unsafe condition." Obviously you cannot specify any possible problem you might have during the t/o run, but would you brief that you will continue if a tyre fails at V1-10? Your FO might never say "V1", he might only say "Stop, max brakes".

We try to make all our procedures as clearcut as possible. How much room is there really for personal interpretation?

I have more questions than answers, but look forward to the input of those with more experience than me.

Junkflyer

At our company it is always the captains decision to abort. Fo should call v1 etc., never stop or abort. A blown tire is not that big a deal just leave the gear down.

Max Angle

Surely, "Before V1 we will CONSIDER aborting for any caution, warning or unsafe condition."

nugpot

How long will you consider it?

Maybe I should expand on my previous post. I fly the CRJ 200. We operate (with a few exeptions) from long runways where V1=Vr-1 with max reduced thrust.

Company policy is that any pilot can call the abort before V1, although the captain will carry it out.

oldebloke

SOMETHING else that hasn't been passed on..Tire failure precludes one from stopping as one doesn't know what one has between the brakes and the concrete(TIRES)..Ergo tire failure decision was way back at 100knots,after that one is COMMITTed to GO as you can assume reduced/no?? tire braking available....V1-5knots is about the same as VEF(twin 1 sec prior)enough time to react with the first stopping move(Power levers/Brakes),as per 25-107,but only in the STOP case not applicable in this scenario..
This was a SIM exercise in the DC10 era,but with the SIM failure schedule these days,one can't practice everything..

Rainboe

I'm really interested in how you have the time to positively and instantaneously identify tyre failure as the cause! There are numerous lurches and bangs and thumps on take-off- the nose wheel oleo causes a lot of racket on the flight deck- how do you know? I never would have been able to confirm it unless the tyre pressure warning on the Eicas came up!

javelin

This happened a while ago at our lot but not with the weather you describe.

Tyre burst just around V1, got airborne, tyre debris down the engine and in the gear well, high vibration and a slow hyd leak. 20 mins later, back on the ground, tea and medals shortly afterwards

rigpiggy

Actually the CAI DC 10 in YVR was after V1, and it was a compressor stall. excerpt from the TSB.

he Transportation Safety Board of Canada (TSB) investigated this occurrence for the purpose of advancing transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability.

Rejected Take-off/Runway Overrun
Canadian Airlines International
McDonnell Douglas DC-10-30ER C-GCPF
Vancouver International Airport,
British Columbia
19 October 1995

Report Number A95H0015

Synopsis

Canadian Airlines International Flight 17 was on a scheduled flight from Vancouver International Airport to Taipei, Taiwan. On board were 4 flight crew, 8 cabin crew, 2 interpreters, and 243 passengers. During the take-off on runway 26 and approximately two seconds after the V1 call, the crew heard a loud bang and felt an airframe shudder and considerable vibration, later attributed to an engine stall. The captain called for and initiated a rejected take-off. The aircraft could not be stopped on the runway, and the nose-wheel gear collapsed as the aircraft rolled through the soft ground beyond the end of the runway. The aircraft came to rest in a nose-down attitude approximately 400 feet off the declared end of the runway. Six passengers were slightly injured during the emergency evacuation of the aircraft.

The Board determined that engine number 1 lost power at a critical point in the take-off and that the rejected take-off was initiated at a point and speed where there was insufficient runway remaining to stop the aircraft on the runway. Contributing to this occurrence were the misidentification of the cause of the loud bang and the lack of knowledge regarding the characteristics of engine compressor stalls. Contributing to the engine power loss was a delay between the collection and analysis of the engine monitoring data.

DOVES

Hi Rainboe!
Do you remember me?!
I am Doves!... Yes that one!
Now you're saying that I was right!
Do you remember when I was supposing how many and how severe reasons there were for a jumbo not to wander around for so many hours with a non certainly caused engine failure during Take off?
On the MD 80 it was written not to abort in case of tire failure from V1-20 on, for obvious reason.
The only problem: they didn't tell us how to recognize it!

tailwheel76

By the time your brain has acknowledged the fact you have heard a bang/thud, looked at EICAS, realised you have still have 2 good engines and said something assertive enough to convince PF to continue, you'd be pretty close to V1 so would go (easily said sitting in a nice warm house with plenty of time to think!).

The other thing is with a blow out on a maingear the aircraft will vear towards it initially, until you apply the brakes, then it will pull the opposite direction, so theres a controlability issue to consider as well.

The thing that I find a grey area now is the meaning of V1. Has it changed from the point at which a decision to stop has been made, to the point at which the actions of stopping have been initiated? Why does the definition keep changing but the speed it is referenced to continue to be the same?

I have a vague recollection from the ATPL's there was a 2 sec recognition followed by a 2 second action period leading up to V1 so therefore a problem must be realised 4 seconds before V1 to ensure adequate runway to stop....right?! So the requirement to call V1 is redundant, as by the time you reach 3 seconds before it, its too late, isnt it?

SlowAndSilly

But what if terrain surrounds the airport? With the gear down it will almost certainly be a problem to make the climb requirements?

brgds

pigboat

On that DC-10 overrun, wasn't the reverse thrust inop on the center engine?

The rule of thumb being, of course, is if you abort at anywhere near V1 you should have as much going for you as possible.

Max Angle

You are only going to have a problem with performance if you lost an engine at the same time, in which case I would suggest that selecting the gear up would be the lesser of two evils.

Centaurus

While it is normal procedure to expect the PNF (let's call him the co-pilot for sake of another term) to expeditiously advise the captain of an abnormality during the take off run, some captains would have strong reservations of him calling "Stop - Max Brakes" or whatever.

CRM is lovely of course but there are critical areas where it is the captain who wears the consequences of what may be the most vital action in his career -a high speed abort. Lawyers would have a field day if the captain pleaded he was only doing what his subordinate had ordered him to do. Surely the captain is capable of deciding and doesn't need the help of a committee of one. Call the event by all means but there is no need to direct the actions of the captain.

Yes I know there are wonderfully switched on highly experienced copilots and so on. There are also some less switched on inexperienced copilots who could not be trusted to land a Tiger Moth on a 10,000 ft runway. I remember recently asking a chief pilot of a very small British "airline" who operates Boeing 737-200's why Jet Upset (Unusual Attitudes) were not part of the company training syllabus. His answer? He said his copilots (some had less than 500 hours total time) were the best trained in UK and he could not possibly envisage them allowing the aircraft to get into a UA in the first place...Er - Yes?

Back to the tyre burst question. There is no correct answer. Historically it is better to take your chances and keep on going if you are within 20 knots of V1. Controllability is rarely a problem in such events but an abort with less than maximum brakes (tyres) is fraught with danger on limiting runways. Reading of past accidents of this nature is also good insurance against making the same mistake. Isn't there an old saying about learning from the mistakes of others?

TenAndie

This is one of those situations that justifies a wage packet in order to be laying on a beach in Barbados 2 weeks, or looking for a new job after having your face plastered on the news for f**king up !!

If V1 is taken literally and is the point where you must go as there isnt enough runway to stop, then surely you must go.

It takes 2 seconds to realise you have a problem and 1 second to decide you are going to stop in which any case is well past V1. If i had a glance and saw that engines were fine, we are going and we sort whatever problems we have in the hold.

I suppose, like anything, its easy enough to speculate until it really happens to you ???

With the Captain/FO debate, we have a different kettle of fish and thats why we have CRM. How many FOs would not say anything thinking the Captain is gonna do the same as they are thinking.

Maybe new aircraft should have a computer fitted that can detect the problem in milliseconds, as in flight, and take the correct course of action immediately. They do everything else for us so why not let them take the flack if it goes tits up

jetblues

My Boeing QRH reads "Above 80 kts and prior to V1, the takeoff should be rejected for any of the following:
* fire or fire warning
* engine failure
* predictive windshear warning
* if the airplane is unsafe or unable to fly

This is an excellent question, and reinforces the fact that you need to be aware and vigilant especially close to V1. The question has two parts for me. Part one the meaning of V1. Is V1 a gate up to which you should have recognised or acted ? I take the view that it is an "action" speed whereby I should have acted. I'm no technical whiz but we are aware that the V1 speed takes into account the fact that an event may have occured just prior to V1 and you have the opportunity to conduct a RTO with said safety parameters intact(refer previous posts).

Part two of the question is really about noises, flight control and recognition of non-normals. I try to simplify the issue by suggesting that firstly we may hear a bang. Next we look at the engine instruments and see if they are "normal". If there are 2 parameters that are not normal then I would consider we may have had an engine problem. Engine failure as opposed to engine damage typically results in continued N1 and N2 rotation.

If the engine instruments appear normal I would certainly consider the possibility of tire damage. We do not have the luxury of EICAS on the 737NG. There are numerous studies on this issue however many have suggested that it would be safer to continue than reject when the aircraft is very close to V1. There are many variables here including runway length, surface condition, wind, aircraft weight etc etc.

The Real Slim Shady

Hmm, V1 is a speed which deals with engine failures.

Not fires or separation. It is the speed at which following an engine failure one may continue the take off etc etc.

The tyre / tire failure and V1, whilst interesting in pure discussion terms, should really be independent.

From a performance aspect it would be prudent to take the failure airborne and, if an immediate landing is required have the full length available for the landing run.

driver airframe

Our company policy states that after 80 kts the take off becomes GO ORIENTATED and the only abort should be for
* fire or fire warning
* engine failure
* unsafe configuration
* if the airplane is unsafe or unable to fly

Remember with a blown tyre you are going to have reduced stopping capability and tyre debis might also have caused damage to the anti skid system and hydraulics which is going to complicate the situation and increase the possibility of an overrun. Rather continue the take off, keep the gear down and assess the situation once airborne. Plan to land back on the most suitable runway available. Identifying the tyre failure seems to be the biggest problem. Havn't had one but I think acceleration should be very close to normal and there might be a swing which should not be to difficult to control on aircraft with more than one wheel per bogie.