Originally Posted by
Helinut
B73 - thanks for pointing me at the second link. However, is it not less to do with the aircraft type/variant but more with the gearbox shaft batch part number/method of manufacture?
It is indeed. And the next section of the 'Fact Sheet' addresses that very point. (Bear in mind the target audience (ie the passengers) so the serial and part numbers themselves are not mentioned). Also, PPRuNE/vbulletin doesn't want to accept the original tabular formatting so I've had to re-jig it slightly:
Why are some Super Pumas flying and others not?
The difference is down to a certain type of component – the main gearbox vertical shaft. For ease, these have been labelled below as shafts 1 and 2.
Type of shaft.......Can be fitted in.......What is it?.........Approved for use?
“Shaft 1”......L, L1 and L2 models........This is the original design of shaft. Has accumulated 4.5 million flight hours without incident......Yes
“Shaft 2”...... L, L1, L2 and EC225 L, L1 and L2 aircraft can be fitter with either Shaft 1 or Shaft 2 If not already so, these will now be re-fitted with shaft 1 in order to be fly again. All EC225s feature shaft 2 and cannot be fitted with Shaft 1........... A change in the manufacturing process of specific batches of Shaft 2 was originally thought to be the cause of the G-REDW ditching in May. New evidence is coming to light which suggests that the scope of the problems associated with Shaft 2 are wider. Use of aircraft which feature this shaft is not supported by the aircraft operators and is also no currently permitted by the CAA.