I must find the report…
Edit.
https://www.faa.gov/sites/faa.gov/files/2022-11/Concorde_Accident_Report.pdf
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Well it happens a lot to be honest, we had some tires explode and it just shreds everything there into bits, electrical boxes, gear panels etc, turns out a tire pumped up to 200PSI when cold has a lot of energy stored that can be released really quickly.
That bottom skin of the fuel tank though, what a horrible design decision.
Also that strip was traced back to the DC10 and then to a mechanic that fabricated it incorrectly, it has been one of the lessons drilled into us at school.
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So, comparing Hutchinsons interview in the video with the accident report, shows some discrepancies…
In the interview it is stated that the Flight Engineer initiated the shutdown of Eng. #2 by himself. The report states several times that it was called by the commander. The report also says that there was some confusion with engine surges on #1 and #2 and yes, #2 was shut down early, but none of this matters because the aircraft was doomed even with all engines working normally…
The missing spacer in the wheel bogie is brought up as a contributing factor in the interview and that the wheels were smoking, probably by the side tracking bogie. The reports states that the missing spacer did not contribute to the accident. Only the burst tire on that bogie had signs of wear and damage.
The report states that the Concorde was about one ton above max takeoff mass, but that this was negligible…!
The report also acknowledges that ATC called a 8kts tailwind but then says that the wind was in reality near zero…?
I’m having trouble making sense of this report. It is as if they disregard the questionable decisions by the crew, because it was the destruction of the tire that caused the leak and subsequent fire.
But, then again, accident reports being influenced by politics is not unheard of…
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Haven’t read too many BEA reports but I suspect they focused on the root cause for the aircraft to go down, all other factors taken into consideration without the root cause would probably have resulted in a normal take-off. Happens a lot with accident investigations once they’ve gathered up the evidence and start to rule out potential causes.
Then again, this is speculation on my part and I am not that intimately familiar with the Concorde crash.
Yes, root cause analysis was probably the tool for these investigators and was de rigueur for the period. Today investigators use a more systemic approach.
But saying that a metric ton overweight is negligible and a 8 kts wind reading is in reality no wind, is really hard to understand as both leads to higher tire loads… Contributing factors, at least…!
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The report is an interesting read, and seems to drive around in a few contradictory circles, likely based on the parties involved and some degree of national pride. It looks like the British were pretty well excluded (near the last few pages) from any real assistance or input, for better or worse.
My take is that if the fuel tanks had not been overfilled, it is very unlikely the tire damage would have resulted in a rupture of the tank, much less the catastrophic fire.
From what I can tell, the inability to retract the gear due to the damaged gear door sensor is what ultimately prevented the aircraft from climbing out, as the climb speed required with two engines failed (#1 not producing power, #2 shut down) was greater than 300 kts in that configuration. If only one engine had failed, it should have been able to maintain altitude and/or accelerate-climb at the achieved airspeed of 200kts. Who knows what the flame jet would have done had it continued, it’s possible that simply having the performance to climb still wouldn’t have resulted in a successful return for landing. There were certainly a number of factors for consideration, and the crew certainly had every one of the odds stacked against them at that point. What a tragedy.
In their defense, they had one bad tire ‘explosion’ early on in '78 (detailed in that report) which resulted in a number of changes (ADs). Then in the next decade they had a several more which resulted in more ADs including two iterations of improved tires, and (IIRC) ‘armoring’ the bottom of the fuel tanks. After that, both the number of tire incidents and the severity of the resulting damage drastically decreased over time, to a point where it was a relative non-event when it did infrequently happen. Successful example of the system working, right?
From what I gather they didn’t consider (nor understand the dynamics of- until the accident and substantial testing and analysis) the fluid shockwave mechanics of a completely full fuel tank (not a normal configuration, since between 800kgs and two tons of fuel gets burned during taxi) being impacted by a substantial piece of tire at high speed. The fuel itself is what actually ruptured the tank (unless I misunderstand the report), with the force of the shockwave punching a hole outward from the bottom of the tank, rather than the tire piercing the tank.
Even in the handful of previous incidents where impacts did pierce the tank, the leak rate was negligible and the resulting damage not critically severe.
It is fascinating, in a similar way to both of our Shuttle disasters.
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Indeed. And the crew stacked some of those odds themselves.
But it seems like the AIB concludes that none of that mattered since it wouldn’t have been an issue if the RWY had been free of FOD… It’s a very simplistic approach to accident investigation, by todays standards.
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Eh I think they have a point, it’s the final piece in the puzzle why it crashed, without that FOD it would have taken off normally given all other circumstances. I think it’s a fair assessment, not that there isn’t anything else to learn from the rest of the conditions though, it’s definitely showing a unhealthy amount of normalization of deviations for one.
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Not sure if this is the right place to post this. Interesting story. So nice to see such volunteering even though always some incompetent bureaucracy on the way
https://www.qcnews.com/news/investigations/sc-pilot-flying-volunteer-supply-and-rescue-missions-ordered-out-of-lake-lure-under-arrest-threat/
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Yes, the car drove at 250kmh but that’s not a factor since the accident wouldn’t have occurred had it not hit the semi truck. 
Root Cause Analysis has its place in accident investigations, but it paints a very simple picture.
You can say they chose the path of least resistance, in that investigation. But it’s over 2 decades ago and lessons have been learned.
That report would look very different, had it been written today, ref. the interview with Hutchinson.
Edit. But in the end I can’t shake the feeling that the report was written like that, in part to take the focus away from Air France and the crew…
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There is a mistaken belief among American local government officials that they have authority over the air six inches above the ground and higher. The R44 owner should have told the fire chief to “gfy”.
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Agreed, and I would have- professionally and calmly. Fire chiefs don’t have powers of arrest anyway, although a fire marshal may in many states, but only over narrow jurisdiction.
Sounds like the fire chief was suffering from a little but of Cartman Syndrome ™
