For all you trainees who think 30 psi is safe....

[Inevertouchedit]

Mid 80s, 27sqn at Marham.

I was on 617 at the time, but a FLM on 27 lost an arm blowin up a noseleg tyre straight from the big bottle trolley - much quicker than using the adaptor/walkround kit !!

 

[burglar]

Mid 80s, 27sqn at Marham.

I was on 617 at the time, but a FLM on 27 lost an arm blowin up a noseleg tyre straight from the big bottle trolley - much quicker than using the adaptor/walkround kit !!

I remember that story reaching LBH. Heard he'd inflated the canopy seal bottle to the same pressure of the blow down having got the two mixed up.
On the subject of blow outs etc not long before I was demobbed I was charging a pitch feel actuator when the turner adaptor blew off whilst I was equalising the pressure having stripped the threads of the charging point. All I heard was a bang and whistle as it went whizzing past my swede (350 psi seems to ring a bell!!). Wingcos face who was stood by the management cabin was a picture!! That was on 27 as well.
Also used to hate the sound of tyres creaking whilst they were being inflated--- scary!!

 

[Scaley brat]

the sound of tyres creaking whilst they were being inflated--- scary!!

Aah, the memories come flooding back. Saints tyre bay, mid 80's. Young long haired brat inflating Tomb mainwheels to 350 or more just to seat the bead. When the bead went in, it went with a f*cking loud bang...... it often took a few seconds before your brain would accept you were still alive, especially when Shanks dropped a big steel ring on the bloody bearing press behind you. DT_Xtremez_25:
It turned your bowels to water DT_Xtremez_31:

 

[Barch]

Once witnessed a linie on IX inflate a Tornado mainwheel tyre to about 15 times over pressure, he hadn't realised that the Nitrogen Trolley was in Bar and he pumped in what he thought was PSI.

 

[Talk Wrench]

Well,

Low Pressure can be just as dangerous as high pressure.

http://www.telegraph.co.uk/news/new...lame-for-Blink-182-drummer-Learjet-crash.html


There is a rather poignant quote. Taken from the article,


"This accident didn't have to happen," said NTSB Chairman Deborah Hersman. The crash, she said, should be a warning to everyone in
the aviation industry that "there are no small maintenance items, because every time a plane takes off lives are on the line."


Wise words, true words and words that are ignored constantly by accountants and pen pushers.


TW

 

[theladf]

Mid 80s, 27sqn at Marham.

I was on 617 at the time, but a FLM on 27 lost an arm blowin up a noseleg tyre straight from the big bottle trolley - much quicker than using the adaptor/walkround kit !!

Amazing the stories you here, I was at Marham at the time (other side of the runway) and heard that he had "got an adaptor" while on det in the USA which allowed high pressure bottles to connect directly to the Schraeder valve on the tyres. This he had done several times previously. However if he had checked the regulator before turning the bottle key he would have seen it set at over 2000PSI!!!!!!!! the rest as they say is (like his arm and the tyre) history...

 

[Past Engineering]

The 27 Sqd incident was from memory, as follows:

They where using the new regulator type nitrogen bottles with the high pressure line (instead of the low pressure line) connected to a Turner adaptor that was attached to the tyre valve, as we did not have the puff boxes at that time. It had nothing to do with bar/psi confusion or directly connecting to the tyre from the nitrogen trolley.

The tyre bay checked the bolts when they were recovered most showed evidence of failure due to fatigue cracks, as this wheel pair had the highest usage, another aircraft that was in the process of taxying was found to have high usage wheels fitted so we recalled it as a precaution and did an engine running nosewheel change, some of these bolts showed evidence of fatigue.

The summing up post the incident of why the wheel exploded was along the lines that; To produce the max tyre pressure from the low pressure line (the norm) took say approx 6 turns of the regulator handle, but as they had mistakenly connected it to the high pressure line, the high pressure regulator when turned approx 6 times at least doubled the pressure available at the turner adapter, but even having said that he was controlling the pressure with the turner adaptor lever and gauge, so it ended up being partially the misuse of the existing equipment we had to work with i.e allowing the tyre to be overpresurised, and the wheel bolt fatigue failure.

As I said to the unit enquiry if you hold the two outlets together and set the low and high pressure regulators to 30 psi that is all you will get out of the end of the line, the WO GEF claimed that if you set the high pressure regulator to 30 psi you will get more than that out of the end of the line.

 

[Inevertouchedit]

The 27 Sqd incident was from memory, as follows:

They where using the new regulator type nitrogen bottles with the high pressure line (instead of the low pressure line) connected to a Turner adaptor that was attached to the tyre valve, as we did not have the puff boxes at that time. It had nothing to do with bar/psi confusion or directly connecting to the tyre from the nitrogen trolley.

The tyre bay checked the bolts when they were recovered most showed evidence of failure due to fatigue cracks, as this wheel pair had the highest usage, another aircraft that was in the process of taxying was found to have high usage wheels fitted so we recalled it as a precaution and did an engine running nosewheel change, some of these bolts showed evidence of fatigue.

The summing up post the incident of why the wheel exploded was along the lines that; To produce the max tyre pressure from the low pressure line (the norm) took say approx 6 turns of the regulator handle, but as they had mistakenly connected it to the high pressure line, the high pressure regulator when turned approx 6 times at least doubled the pressure available at the turner adapter, but even having said that he was controlling the pressure with the turner adaptor lever and gauge, so it ended up being partially the misuse of the existing equipment we had to work with i.e allowing the tyre to be overpresurised, and the wheel bolt fatigue failure.

As I said to the unit enquiry if you hold the two outlets together and set the low and high pressure regulators to 30 psi that is all you will get out of the end of the line, the WO GEF claimed that if you set the high pressure regulator to 30 psi you will get more than that out of the end of the line.

Thanks for that. Excuse the lapses in my memory, but it was a while back.

As an ex-fairy, I'd like to point out that I understood some of the above !!