Old 1st May 2016, 13:32
  #201 (permalink)  
Join Date: Jul 2002
Location: ZA
Age: 62
Posts: 19
There is no reason so far to believe that this accident is not a repeat of the G-REDL incident. I was not very satisfied with the report on this accident as it struck me as being complacent, that just to keep on doing the same things, but better was going to prevent the same thing happening again.
In the repotr it was said:-
"Safety Recommendation 2011-036 It is recommended that the European Aviation Safety Agency (EASA) re-evaluate the continued airworthiness of the main rotor gearbox fitted to the AS332 L2 and EC225 helicopters to ensure that it satisfies the requirements of Certification Specification (CS) 29.571 and EASA Notice of Proposed Amendment 2010-06."
Was this done?
The report contains the following passage:-
"Epicyclic gearbox spalling events on the AS332 L2 helicopter Data provided by the helicopter manufacturer indicated that between 2001 and 2009 there were nine recorded cases of planet gear spalling on the AS332 L2 (see Table 2). In addition, information provided by the operator showed that there had been seven events in 2010 on their fleet where magnetic particles had been found on the MGB magnetic chip detectors which had resulted in the removal of the gearbox for repair. The information provided by the manufacturer regarding the number of planet gear rejections due to spalling was incomplete. During the investigation anecdotal evidence was provided that indicated that overhaul facilities disposed of rejected gears without routing them for investigation."
This indicates to me a high level of complacency, the kind that brought down two NASA shuttles. Bearing spalling is not something you ever want to see in a gearbox, as it's progression is not predictable and often results in rolling elements being deposited into the gear mesh. At which point it is game over for the gearbox.
mostlylurking is offline