Kiwi B777 burst 12 tyres in aborted takeoff at NRT
Join Date: Apr 2002
Location: FUBAR
Posts: 3,348
Likes: 0
Received 0 Likes
on
0 Posts
Well, whatever you chose, it was right 
as you are here to tell the tale.
We are encouraged to be "go minded", and on a limiting runway this can be sound advice. . . But , if you look at the Concorde crash where V1 was about 150kt ? and Vr about 200kt, it would be difficult to argue the logic of his decision had he somehow known what was behind him.
As far back as the Manchester B Airtours accident there seemed to be a possibility we could end up with external cameras.
If you look at the technology and miniaturisation available today, it is shameful it has never come to fruition.
Had the Concorde crew seen what could be seen externally, there is no way they wouldn't have aborted (even at Vr of 200kt) and it would have been a good decision, as we can now see with the benefit of hindsight.
RTO's may not be funny, but they are preferable to taking something into the sky you have no certainty of controlling.
The AF 777 @ Lagos was a foul up it seems, but the decision to abandon based on the crews perception of lack of controllability (not correct, as it transpired, and probably just a problem of their own creation ) was a good call nonetheless.
as you are here to tell the tale.We are encouraged to be "go minded", and on a limiting runway this can be sound advice. . . But , if you look at the Concorde crash where V1 was about 150kt ? and Vr about 200kt, it would be difficult to argue the logic of his decision had he somehow known what was behind him.
As far back as the Manchester B Airtours accident there seemed to be a possibility we could end up with external cameras.
If you look at the technology and miniaturisation available today, it is shameful it has never come to fruition.
Had the Concorde crew seen what could be seen externally, there is no way they wouldn't have aborted (even at Vr of 200kt) and it would have been a good decision, as we can now see with the benefit of hindsight.
RTO's may not be funny, but they are preferable to taking something into the sky you have no certainty of controlling.
The AF 777 @ Lagos was a foul up it seems, but the decision to abandon based on the crews perception of lack of controllability (not correct, as it transpired, and probably just a problem of their own creation ) was a good call nonetheless.
Join Date: Aug 2007
Location: San Antonio, TX USA
Age: 62
Posts: 139
Likes: 0
Received 0 Likes
on
0 Posts
If I were in your position then, Eckhard, I'd have been aiming for the sky. If that is the wrong decision, then thank goodness I am not a pilot.
Kudos for making the obvious correct decision.
Kudos for making the obvious correct decision.
Thanks for the replies. No, it wasn’t at YYZ.
And the correct answer (What did I do?) is............. (drum roll)............
I stopped.
Why?
Because I was scared that we were going off the side of the runway at high speed and I figured that if that happened, I would rather be slowing down already instead of blasting along at full power.
I wasn’t sure that we could get airborne before we left the paved surface, partly because the ASI was unreadable with all the vibration. Also, although I felt that the swing and vibration was caused by a tyre problem, I was not certain that some other damage to the flight controls, engines or structure had occurred.
The 'bottom line' was that the aircraft was in effect 'out of control' and I wanted to get it back under control. The simplest way seemed to be to close the thrust levers and hit the brakes. The decision was influenced by the fact that my last memory of the ASI was that it was below V1 and that there seemed to be quite a lot of runway remaining.
We closed the thrust levers, applied brakes (deployed the speedbrakes as well) and were worried to find that the RH brake pedal was 'floppy' and had no effect. The LH pedal seemed to be working but that gave us a yaw, which, although in a beneficial sense to start with, was going to give us problems eventually......so we took our feet off the brakes and used the manual emergency brake handle.
As this was happening, the vibration stopped and the aircraft adopted a right-wing-low attitude. The rudder was effective in helping us regain and maintain the centreline until the speed reduced.
We slid to a stop on the centreline with about 2,000ft of runway remaining. Everything from that point on (shutdown, ATC comms, Fire Services, etc) was as ‘routine’ as you would expect.
On inspecting the damage, the RH tyre had completely disappeared, the RH wheel rim was worn into a ‘D’ shape, the RH flap, gear door, lower wing and tailplane had impact damage from the rubber fragments and the RH brakes were leaking fluid.
There was a bright metal skid mark leading back from the RH wheel down the runway, which then changed into a black rubber skid mark.
The ‘balanced field length’ for this take-off was about 4,000ft. We had a 10,000ft runway and we elected to use the full length. OAT was about 32C and the elevation was about 1,000ft.
We used 8,000ft of runway, about double the ‘book figure’ for the conditions. I think this is explained by the following factors:
Did I make the right decision?
Thanks to those who point out that it can’t have been so bad, as I’m here to tell the tale. Based on the successful outcome and the actual damage inflicted on the aircraft (over $100,000 repair bill) I think on balance it probably was the right decision. Had I managed to get the thing airborne, I think in retrospect it would have been flyable. I would have kept the gear down and eventually would have landed back on the full length of the 10,000ft runway. Against that, the extensive damage that I saw after the event helped to convince me that keeping it on the ground was the right thing to do. I did have some doubts during the initial few minutes after we stopped: ‘Were we above V1?’ ‘In the simulator, we were trained to continue the take-off.’ ‘Could I have got airborne before going off the side?’ etc, etc.
On the other hand, if we had got airborne, we could have had jammed elevators, jammed flaps, fuel leaks, etc. The damage was serious enough that all of these ‘nasties’ were a real possibility.
To be perfectly honest, I just had a ‘bad feeling’ as we were sliding towards the side of the runway, and ‘self-preservation’ over-ruled the theoretical training which was going round my head at the time. It was almost instinctive to close the thrust levers.
What did I learn?
1. Self-preservation is a very powerful impulse; it can be difficult to resist even if your training tells you that another course of action may be appropriate.
2. Balanced field lengths assume timely and correct action in the event of an RTO. They also assume that the brakes will be working correctly.
3. The old adage, ‘one of the most useless things is runway behind you’ is true! Intersection take-offs are of course fine, but the full length is better!
4. Burst tyres can cause loss of control, severe difficulty in reading the instruments and lots of structural damage.
5. A real ‘event’ is probably going to be quite different to what you have seen in the simulator.
Hope this is of interest.
Eck
And the correct answer (What did I do?) is............. (drum roll)............
I stopped.
Why?
Because I was scared that we were going off the side of the runway at high speed and I figured that if that happened, I would rather be slowing down already instead of blasting along at full power.
I wasn’t sure that we could get airborne before we left the paved surface, partly because the ASI was unreadable with all the vibration. Also, although I felt that the swing and vibration was caused by a tyre problem, I was not certain that some other damage to the flight controls, engines or structure had occurred.
The 'bottom line' was that the aircraft was in effect 'out of control' and I wanted to get it back under control. The simplest way seemed to be to close the thrust levers and hit the brakes. The decision was influenced by the fact that my last memory of the ASI was that it was below V1 and that there seemed to be quite a lot of runway remaining.
We closed the thrust levers, applied brakes (deployed the speedbrakes as well) and were worried to find that the RH brake pedal was 'floppy' and had no effect. The LH pedal seemed to be working but that gave us a yaw, which, although in a beneficial sense to start with, was going to give us problems eventually......so we took our feet off the brakes and used the manual emergency brake handle.
As this was happening, the vibration stopped and the aircraft adopted a right-wing-low attitude. The rudder was effective in helping us regain and maintain the centreline until the speed reduced.
We slid to a stop on the centreline with about 2,000ft of runway remaining. Everything from that point on (shutdown, ATC comms, Fire Services, etc) was as ‘routine’ as you would expect.
On inspecting the damage, the RH tyre had completely disappeared, the RH wheel rim was worn into a ‘D’ shape, the RH flap, gear door, lower wing and tailplane had impact damage from the rubber fragments and the RH brakes were leaking fluid.
There was a bright metal skid mark leading back from the RH wheel down the runway, which then changed into a black rubber skid mark.
The ‘balanced field length’ for this take-off was about 4,000ft. We had a 10,000ft runway and we elected to use the full length. OAT was about 32C and the elevation was about 1,000ft.
We used 8,000ft of runway, about double the ‘book figure’ for the conditions. I think this is explained by the following factors:
- We were very close to V1 when the problem occurred;
- We took a few seconds to recognise, control, analyse, and decide; and
- The braking effort was not 100%.
Did I make the right decision?
Thanks to those who point out that it can’t have been so bad, as I’m here to tell the tale. Based on the successful outcome and the actual damage inflicted on the aircraft (over $100,000 repair bill) I think on balance it probably was the right decision. Had I managed to get the thing airborne, I think in retrospect it would have been flyable. I would have kept the gear down and eventually would have landed back on the full length of the 10,000ft runway. Against that, the extensive damage that I saw after the event helped to convince me that keeping it on the ground was the right thing to do. I did have some doubts during the initial few minutes after we stopped: ‘Were we above V1?’ ‘In the simulator, we were trained to continue the take-off.’ ‘Could I have got airborne before going off the side?’ etc, etc.
On the other hand, if we had got airborne, we could have had jammed elevators, jammed flaps, fuel leaks, etc. The damage was serious enough that all of these ‘nasties’ were a real possibility.
To be perfectly honest, I just had a ‘bad feeling’ as we were sliding towards the side of the runway, and ‘self-preservation’ over-ruled the theoretical training which was going round my head at the time. It was almost instinctive to close the thrust levers.
What did I learn?
1. Self-preservation is a very powerful impulse; it can be difficult to resist even if your training tells you that another course of action may be appropriate.
2. Balanced field lengths assume timely and correct action in the event of an RTO. They also assume that the brakes will be working correctly.
3. The old adage, ‘one of the most useless things is runway behind you’ is true! Intersection take-offs are of course fine, but the full length is better!
4. Burst tyres can cause loss of control, severe difficulty in reading the instruments and lots of structural damage.
5. A real ‘event’ is probably going to be quite different to what you have seen in the simulator.
Hope this is of interest.
Eck
Checkboard;
My original post, if read by a non-aviator who doesn't know about these things, would leave the impression that "tires burst" but I'm writing in a forum where professionals dwell and my meaning, not made as clearly as I am accustomed to making, was nevertheless clear to everyone else - that the fuseable plugs did their job.
Let's not get stuck on minutae, but try to turn our focus on why the reject occurred. I did mention in my post that there have been at least seven other incidents not counting the Air France Lagos B777 reject where the autopilot was inadvertently engaged on takeoff and the comment was "the aircraft could not be rotated". That is an interesting bit of information.
Nobody rejects because the autothrust wouldn't engage, especially under those circumstances - at least I sure hope not.
Rather, there is a large issue lying dormant here which I thought that others reading PPRuNe would have picked up on the Lagos thread immediately and at least began thinking about even though we don't have any data yet. There was a comment early in the thread that the control column could not be moved back for rotation. I think that is a huge flag even unconfirmed at this early stage. (As an aside, I see someone has mentioned it yet again which tells me that that person and others do not read the entire thread before posting).
The other question Checkboard is, why would anyone take what the media has to say about such incidents seriously and then actually comment? We are professional airline pilots; we wait for data and, where inclined, speculate intelligently from knowledge and experience.
regards,
PJ2
That means that it's a bit rich to say "12 tyre bursts are not important"
Let's not get stuck on minutae, but try to turn our focus on why the reject occurred. I did mention in my post that there have been at least seven other incidents not counting the Air France Lagos B777 reject where the autopilot was inadvertently engaged on takeoff and the comment was "the aircraft could not be rotated". That is an interesting bit of information.
Nobody rejects because the autothrust wouldn't engage, especially under those circumstances - at least I sure hope not.
Rather, there is a large issue lying dormant here which I thought that others reading PPRuNe would have picked up on the Lagos thread immediately and at least began thinking about even though we don't have any data yet. There was a comment early in the thread that the control column could not be moved back for rotation. I think that is a huge flag even unconfirmed at this early stage. (As an aside, I see someone has mentioned it yet again which tells me that that person and others do not read the entire thread before posting).
The other question Checkboard is, why would anyone take what the media has to say about such incidents seriously and then actually comment? We are professional airline pilots; we wait for data and, where inclined, speculate intelligently from knowledge and experience.
regards,
PJ2
See my learning points #1 and #4 above.
If the aircraft cannot be rotated, self-preservation will probably dictate that you abort.
Unless a take-off with the AP engaged is practised in the sim (if indeed this is what happened) you will not have seen this before and so there is no training that applies, except for 'reject if the aircraft is unflyable'.
Eck
If the aircraft cannot be rotated, self-preservation will probably dictate that you abort.
Unless a take-off with the AP engaged is practised in the sim (if indeed this is what happened) you will not have seen this before and so there is no training that applies, except for 'reject if the aircraft is unflyable'.
Eck
Join Date: Dec 2000
Location: Somerset
Posts: 78
Likes: 0
Received 0 Likes
on
0 Posts
Yet another excellent post from PJ2.
If non-aviators wish to contribute I would strongly suggest they read all PJ2's posts on the subject first. They are much more likely to understand the nature of the problem before rushing in mouth first!
If non-aviators wish to contribute I would strongly suggest they read all PJ2's posts on the subject first. They are much more likely to understand the nature of the problem before rushing in mouth first!
I admit my initial post was a little abrupt. Also not as clear as I usually intend, and rather than "above V1" should have read "high energy" ("above V1" being the most interesting subset of "high energy"). Having said that, however, my personal dislikes in accident & incident threads are posts which say:
The incident was reported, it was obviously high energy, speculation about where V1 existed in the event is relevant - and none of this is any comment about the role played by the pilots. I am of course aware of the limitations of first information (usually from the media.).
Exactly.
- wait until all of the facts are in
- wait for the report
- the pilots did a great job
- the pilots did a terrible job
- this incident is nothing
- (in the case of fatal accidents) God bless all those who have perished, my thoughts are with you ... etc
- those posts I disagree with are obviously wannabes with no experience in aviation
The incident was reported, it was obviously high energy, speculation about where V1 existed in the event is relevant - and none of this is any comment about the role played by the pilots. I am of course aware of the limitations of first information (usually from the media.).
where inclined, speculate intelligently from knowledge and experience.
e28 driver
Join Date: Jan 2002
Location: UK
Posts: 211
Likes: 0
Received 0 Likes
on
0 Posts
Not strictly relevant I know, but I rejected a take off in a P68 at MTOW years ago after I found I couldn't rotate it. I'll never know for sure but it was probably the autopilot being engaged or severely mistrimmed. Still gives me a cold sweat when I remember how I felt when I went for the brakes and almost nothing happened. As the end of the runway approached I pulled the mixtures and dodged the runway end lights. We stopped about 10 feet short of the perimeter fence and I managed to start it up, turn it around and taxi back to the runway and then to the apron without anyone noticing as it was a small uncontrolled GA airport.
It does concentrate my mind on every takeoff I do in the RJs I fly now though...
It does concentrate my mind on every takeoff I do in the RJs I fly now though...
Join Date: Mar 2007
Location: Roguesville, cloud cuckooland
Posts: 1,197
Likes: 0
Received 16 Likes
on
5 Posts
The aircraft in question performed a high speed rejected T/O below V1.
Whatever problem they had, they considered it fixable as they requested a parking bay simply to get more fuel. They taxied clear of the runway, requested Fire services to check their undercarriage. Shortly after the fuse plugs melted and it became apparent they weren't going anywhere.
They then requested buses to get their passengers off.
They had stopped on taxiway alpha and ATC closed the runway for about 30 minutes for a check for debris. After the runway opened arriving aircraft were advised they needed to clear the runway by A3.
This from a source that listened to the whole thing.
Whatever problem they had, they considered it fixable as they requested a parking bay simply to get more fuel. They taxied clear of the runway, requested Fire services to check their undercarriage. Shortly after the fuse plugs melted and it became apparent they weren't going anywhere.
They then requested buses to get their passengers off.
They had stopped on taxiway alpha and ATC closed the runway for about 30 minutes for a check for debris. After the runway opened arriving aircraft were advised they needed to clear the runway by A3.
This from a source that listened to the whole thing.
Join Date: Jul 2002
Location: Ireland
Posts: 596
Likes: 0
Received 0 Likes
on
0 Posts
Air New zealand reported that the a/c taxied clear. Was that a good idea from an engineering point of view, running on rims must cause extra damage musn't it ?
a) The fuse plugs don't 'pop' immediately as they need time for the heat from the brake assembly to reach them giving 4-5 minutes of taxiing time.
b) They don't all pop at the same time so with 12 wheels most of the time you are taxiing 'on rubber' rather than 'on steel'.
SoS
they requested a parking bay simply to get more fuel.
Above 80 knots the takeoff is rejected for fire or fire warning, engine failure, predictive windshear warning, (for others, this means aircraft system warning, not other airplanes or tower warnings), or the airplane is deemed unsafe or unable to fly. There are no other AOM-required conditions to reject the takeoff; in other words, after 80 knots the book is "go-minded" except for the above.
As per reported radio communications, a willingness to go again after a refueling indicates that none of the above occurred except (we must assume) the last reason. Whatever it was, was evidently assessed, understood and then cleared right away, without maintenance intervention, (ie, cb or system resets, changing PFM boxes, flight control problem, which usually grounds an airplane, etc). That information narrows the category of such faults (which render the airplane "unsafe" or "unflyable") even further.
One assumes that the FMA annunciations were read, announced and monitored as per SOP. An announcement of autothrust status is required when thrust is set and then at 80 knots. The call at 80 knots is a challenge - response requirement.
I think that both the recorders and the QAR (FOQA recorder) would be pulled and examined; this is Japan so the investigation will be very robust and detailed.
Checkboard, no worries - everyone's keen to find out and thank goodness for that. PJ2
Join Date: Aug 2005
Location: fairly close to the colonial capitol
Age: 55
Posts: 1,693
Likes: 0
Received 0 Likes
on
0 Posts
The fusible plugs are placed on the rims, near the brake assembly in order to react to heat generated from the brake pack. If the heat in the tyre is not generated from the brake pack (i.e. it is generated in the tyre itself during long taxi operation for instance) then the fusible plugs more often than not won't operate (as rubber is a poor conductor of heat, sufficient heat doesn't reach the plug) and the tyre will burst.
I have it my mind that I saw a report about the FAA loading a 747 up and taxiing it around on a desert airfield. After 9 miles, the first fusible plug went.
I also have heard of tyres deflating at Jeddah where, I believe, it is a very long taxi from the Haj terminal to the runway.
I also have heard of tyres deflating at Jeddah where, I believe, it is a very long taxi from the Haj terminal to the runway.
Last edited by JW411; 6th Feb 2010 at 07:48.
I've never heard of a fuse plug meting due to taxiing or anything tire related.
Yes, indeed.
I once had BOTH tires burst on one bogie of a 737 whilst taxiing in after a normal landing.. Seems the first sent shrapnel into the second.
I once had BOTH tires burst on one bogie of a 737 whilst taxiing in after a normal landing.. Seems the first sent shrapnel into the second.
Join Date: Nov 2006
Location: SoCalif
Posts: 896
Likes: 0
Received 0 Likes
on
0 Posts
Air or Nitrogen?
Are we sure that tires everywhere are being filled with nitrogen, and not air? The difference can be explosive, as you know.
With third party maintenance, especially, there are opportunities to cut costs, and this would be one.
GB
With third party maintenance, especially, there are opportunities to cut costs, and this would be one.
GB
Join Date: Oct 2009
Location: Durham
Posts: 483
Likes: 0
Received 0 Likes
on
0 Posts
Unbelievable
"Whatever problem they had, they considered it fixable as they requested a parking bay simply to get more fuel. They taxied clear of the runway, requested Fire services to check their undercarriage. Shortly after the fuse plugs melted and it became apparent they weren't going anywhere."
Gave a lift to a bloke once..he was an NZer..a farmer. Told me his son worked in civil aviation after the military. Now most farmers learn young often by trial and error and the occasional kick up the A from elders. This was NOT his son....tractor drivers know all about brakes and heat and damage and costs...this team had zero idea of what they had just asked the machine to do.
Gave a lift to a bloke once..he was an NZer..a farmer. Told me his son worked in civil aviation after the military. Now most farmers learn young often by trial and error and the occasional kick up the A from elders. This was NOT his son....tractor drivers know all about brakes and heat and damage and costs...this team had zero idea of what they had just asked the machine to do.
Join Date: Sep 1998
Location: wherever
Age: 55
Posts: 1,616
Likes: 0
Received 0 Likes
on
0 Posts
The 777 OPT does not do a Balanced Field calculation. It does an optimized or improved climb calculation depending on where it is limited. I don't know if the Kiwis have an EFB or if they use RTOW charts. In any case, it very possibly was not a balanced field calcultion so for anyone to suggest that an abort above V1 is not viable is BS. If this is too confusing for you, good. Go to the spotters forum.
They had an incident, no one was hurt, and the a/c can be used again. Good result!!! That's all we know. Pronouncements by wannabes don't further our understanding.
They had an incident, no one was hurt, and the a/c can be used again. Good result!!! That's all we know. Pronouncements by wannabes don't further our understanding.
Tosh!
If they were accel stop field limited then they would be off the end.
Join Date: Jun 2001
Location: UK
Posts: 114
Likes: 0
Received 0 Likes
on
0 Posts
Gentlemen,
Setting aside this particular incident there is a fair amount of rubbish being talked on this thread about 777 take off performance.
When V1 is determined for a particular take off it will always be safe to go above this speed following an engine failure and it will always be safe to stop below this speed. (Assuming no multiple failures!)
Usually in a 777 V1 and Vr will be coincident, sometimes there will be a small gap. If an increased climb performance is required it may be a large gap.
From a pilots view the difficulty is that you have no idea what the go speed and the stop speed actually are, only that V1 is between them. On some days it would be safe to continue 20 kts (or more) below V1 and on some days it would be safe to stop 20 kts (or more) above V1. YOU JUST DONT KNOW!
Setting aside this particular incident there is a fair amount of rubbish being talked on this thread about 777 take off performance.
When V1 is determined for a particular take off it will always be safe to go above this speed following an engine failure and it will always be safe to stop below this speed. (Assuming no multiple failures!)
Usually in a 777 V1 and Vr will be coincident, sometimes there will be a small gap. If an increased climb performance is required it may be a large gap.
From a pilots view the difficulty is that you have no idea what the go speed and the stop speed actually are, only that V1 is between them. On some days it would be safe to continue 20 kts (or more) below V1 and on some days it would be safe to stop 20 kts (or more) above V1. YOU JUST DONT KNOW!