LH engineer seriously injured at MAN 13th Nov
if a heavy truck is passing me on the motorway I always wind the window up just in case,
Why do I wind the window up, well as far as I know side windows on cars are toughened so no big lumps of glass to cut the jugular, saying that you can only try to protect yourself with whatever you have,
To who ever asked about big truck tyres and inflation pressures, it about 120psi.
Nick.
To who ever asked about big truck tyres and inflation pressures, it about 120psi.
Nick.
Reverting to the need for nitrogen inflation please, and just a little off thread. Tyre rubber compounds break down over time and emit volatile flammable compounds. If tyre is inflated with air the internal mixture is potentially explosive, hence the need to use inert nitrogen.
If I remember correctly nitrogen inflation only became mandatory as a result of accident to Mexicana B727 in March 1986. Details at http://aviation-safety.net/database/record.php?id=19860331-1&lang=en. Airlines did not willingly embrace the change!
If I remember correctly nitrogen inflation only became mandatory as a result of accident to Mexicana B727 in March 1986. Details at http://aviation-safety.net/database/record.php?id=19860331-1&lang=en. Airlines did not willingly embrace the change!
Well spotted Hotdog,... but without wanting to pick a fight that pic is the inboard half of the wheel as Terry stated, you can see the splines where it engages on the brake rotors. Good pic tho!
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No it is not Terry. I took the picture after I made them change the wheel.
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Normally in such cases....Its the lack of a pressure regulator used while Tire servicing.
Non deflation of the tire prior to removal.
Excessive serviced.
Sad event.....
regds
MEL
Non deflation of the tire prior to removal.
Excessive serviced.
Sad event.....
regds
MEL
The Reverend
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Sorry vs69, SMOC et al. The picture is as I saw it on my walkaround. It is the No. 12 body gear wheel on a 747F-200 in Manchester. As I was the chief check and training flight engineer on the fleet, I used this picture in a notice to F/Es to keep their eyes open. If you have access to a B747-200 Maintenance Manual, have a look at 35-45-00. The picture is of the outboard wheel half.
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Inboard or outboard, i'm surprised the wheel was clean enough to see the cracks.
All ours are usually covered in a layer of sooty black brake dust.
Either way it was a good spot as a lot of crews tend to focus on the tyres on their walkround.
All ours are usually covered in a layer of sooty black brake dust.
Either way it was a good spot as a lot of crews tend to focus on the tyres on their walkround.
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re-Commercial vehicle tyres.....they're designed for lower speed,poorer surface,much more load-variation and long cycles,
Thick tread and sidewalls (curb impact is an everyday occurence) heavy carcass construction.....they are not designed to smack onto a road with a speed differential of~150 mph, though!
when a commercial tyre blows, the chunks are probably bigger and heavier, pro -rata, compared with Aviation tyres.
Av. tyres appear to be of substantially larger cross-section,therefore, given the higher inflation pressure,I'd suggest:-
close in, both types are lethal if they let go........Av tyres the danger diminishes much more rapidly with distance (see the fire video) as the weight and energy is lower in the "shrapnel" compared with a road-tyre..
Safety inspector for my compressor reservoir had many a tale about tyres and deceased ex-customers.
Thick tread and sidewalls (curb impact is an everyday occurence) heavy carcass construction.....they are not designed to smack onto a road with a speed differential of~150 mph, though!
when a commercial tyre blows, the chunks are probably bigger and heavier, pro -rata, compared with Aviation tyres.
Av. tyres appear to be of substantially larger cross-section,therefore, given the higher inflation pressure,I'd suggest:-
close in, both types are lethal if they let go........Av tyres the danger diminishes much more rapidly with distance (see the fire video) as the weight and energy is lower in the "shrapnel" compared with a road-tyre..
Safety inspector for my compressor reservoir had many a tale about tyres and deceased ex-customers.
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Hi Ozaub,
You are absolutely correct. A dragging brake caused that accident and the gas involved was Isoprene, which is given off by rubber when it gets hot. Isoprene is highly explosive in the presence of compressed air and in the Mexicana flight, the exploding tyre fractured the hydraulic lines in the wheel well, causing the accident.
Nitrogen is also used in struts and accumulators to prevent Dieseling that would occur between the hydraulic oil and any compressed air previously used.
You are absolutely correct. A dragging brake caused that accident and the gas involved was Isoprene, which is given off by rubber when it gets hot. Isoprene is highly explosive in the presence of compressed air and in the Mexicana flight, the exploding tyre fractured the hydraulic lines in the wheel well, causing the accident.
Nitrogen is also used in struts and accumulators to prevent Dieseling that would occur between the hydraulic oil and any compressed air previously used.
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What a horrible accident! I hope the engineer gets well soon!
Does anybody have any hint as to where I could find out who he was? I did two internships at Lufthansa CityLine-Technik in Hamburg and am kind of afraid that it was one of the people I know. Not that that would make it any worse, I would just still like to know... On the other hand I'm not sure if it is the right gesture to call CLH-Technik and ask...
Thanks for any advice.
All the best and fly safe!
-Jakob
Does anybody have any hint as to where I could find out who he was? I did two internships at Lufthansa CityLine-Technik in Hamburg and am kind of afraid that it was one of the people I know. Not that that would make it any worse, I would just still like to know... On the other hand I'm not sure if it is the right gesture to call CLH-Technik and ask...
Thanks for any advice.
All the best and fly safe!
-Jakob
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Have to agree with Terry. I find it difficult to understand how the picture shown of the cracked wheel could have been visable on a pre-flight. The picture is of the I/B side, the brake pack covers this area completely. (unless the outer split sheel was cracked also)
I hope the injured engineer gets well soon.
I hope the injured engineer gets well soon.
The Reverend
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Date: 6th October, 1993
From: C.F.E.T. TO: All Aircrew
Subj : Wheel inspections
The attached illustration shows the #12 main wheel (right rear body gear) removed from ****** at ********** recently.
It is very unlikely that the damage to this wheel occured during the last landing. This highlights the necessity to carry out a thorough inspection of all wheels during walkaround checks. Although several broken wheel tie bolts have been discovered by our crews during walkaround inspections on *** airplanes in the past, damage of this type could easily be missed by a cursory inspection.
The potential consequences of this wheel disintegrating need no elaboration.
Regards,
*************
*************
Chief Flight Engineer, Training.
Last edited by HotDog; 17th Nov 2008 at 22:10. Reason: Addition of Memo to Crew
Warning Toxic!
Disgusted of Tunbridge
Disgusted of Tunbridge
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Can one of you tyre experts say what is the best way for checking tyre pressure for pilot walkarounds as in seeing if a tyre is deflated? Thinking in terms of medium jet tyres. Widebody tyres just seem rock hard whatever their pressure.