Well,
Away for a few days and it seems I have a new handle (the mouth), nice ring to it.
For Overtalk,
My qualifications are my concern, but for your info I am a UK qualified licenced engineer, both CAA and JAA with 757 A/B2/C type rating on my licence, which I have held since '87. I am also an incorporated engineer and a member of the RAeS.
From August '97 to March 98, I was employed at RNAC by a western 3rd party maintenance organisation to oversee the line maintenance at KTM on RNAC's B757's (the company had been contracted to carry the maintenance for RNAC, both line and hangar).
When I have more time to write I may say a little more about my experiences at RNAC, Indeed I may speculate a little more about the possible causes of the triple IRS failure.
For now I will say this. I suspect the IRS failure may have been down to poor racking. I recall replacing an IRU at RNAC which required some force to correctly rack. It may be that others were equally difficult to rack resulting in poor pin contact which became apparent as T/O power was applied. This may provide some clue as to why the crew did not, or were not able to, select ATT to restore at least horizontal and directional information to the EHSI and EADI, as I am sure this would be a QRH action (I don't have a QRH to hand to verify)
This scenario may also explain why at first there was only one U/S IRU, then all 3, then back to just one, as some re-racking may have taken place to attempt to restore servicability and perhaps move a U/S IRU from the left side to another position to restore GPWS data (IRU is hard wired not switched into the GPWC, so a U/S IRU can mean certain GPWS terrain envelope modification is not enabled).I cannot say more than this as I don't know enough information as to the current RNAC a/c mod state.
Qavion, You are of course right, TOGA press sets the datum for FMGC PPOS (runway threashold). The 757 anti-skid is identical in operation to the 76 with the exception that the normal a/skid uses the right system not the centre.
Hope this clarifies things.
Cheers,
Mono (the mouth)
