Back to work in the back of the 139 soon.
Excerpts from e-mail today
"
the reason for the tailboom failure on the Gulf Helicopters AW 139 has been identified as a weakening of the structure caused by an earlier tailboom strike (March 2009). This damage was not detected during post-incident inspections and the weakened tailboom structure failed when a high (not excessive) load was placed on it during the ground taxi. AW has developed new ultrasonic tests to be applied to any tailboom that has suffered any form of impact damage to ensure that the potential internal damage can be detected. Furthermore, AW have developed a modification (Bollettino Tecnico 139-200) to strengthen the tailboom structure by the addition of ‘doubler’ plates and extended longerons. In addition, and most importantly, the investigation proved that the well-known tailboom delamination problem did not contribute to the failure. This delamination problem appears to have been addressed in the latest generation tailbooms, which have aluminium (Al) skins.”
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At 0645 hours on 25th August 2009, the AW 139 Helicopter with registration mark A7-GHC (S/N 31225) was ready for take off and while performing the U-turn during taxing in the direction of the taxiway, the tail boom structure collapsed. This helicopter had a tail boom strike prior incident prior to this event. An Aircraft Accident Investigation Committee with Accredited Representative from the Italian AIB (ANSV) and an Advisor from the Manufacturer was created by the Qatar Civil Aviation Authority (QCAA) to perform the investigation. The Helicopter with the failed tail boom assembly was examined and inspected at the location of the event and later sent to the Manufacturer facility in Italy for further testing, investigation, evaluation and modifications under the Qatar AAIC oversight.
Based on the results of the investigation, the tail boom fracture under ground taxing load was recognized as static failure mode. The structure collapse derived from compression failure of the RH panel with external skin bucking and tension failure on the LH side panel. The RH panel failed area resulted in an external skin debonding for about 40% of the section involving the flat and curved zones.
The helicopter than went through a series of modifications at the manufacturer facility in Italy, was tested and its airworthiness is approved by the manufacturer and Qatar Civil Aviation Authority. This helicopter returned to Gulf Helicopters in Doha last week.
Improvements and modifications done to the AW 139 fleet:
1. The first step of improvements implemented a new manufacturing process and design of the panels. The design of manufacturing has been improved by introducing supported adhesive on all the panel surface.
2. The second step of improvements implemented the production curing phase of the panels. The load pressure during autoclave curing process has been increased to enhance adhesion of the honeycomb in the corners areas.
3. The third step of improvements introduced metallic (aluminium) Flexcore honeycomb and increased the pressure during autoclave curing process. Mandatory periodic destructive test every 25 manufactured panels are required in addition to the curing coupons tests.
4. The fourth improvement step reinforced the tail fin area spars to enhance the tail boom.
5. Gulf Helicopter Aircraft maintenance Program requirements for this helicopter has been reviewed and approved by QCAA. Gulf Helicopters and its helicopter fleet is under continuing safety monitoring and oversight surveillance by the QCAA.
Shellair conducted an audit of Gulf Helicopters after arrival of this aircraft in Doha, which incorporated ConocoPhillips audit requirements. The audit team is satisfied that the tail boom modification on the AW139 helicopter A7GHC has been incorporated and that Gulf Helicopters maintenance staff are competent to conduct ongoing inspection requirements on the tail boom.
Based on the improvements done to the aircraft and the subsequent positive audit by Shellair of Gulf Helicopters, Qatargas 3&4 Shareholders Aviation Advisors have approved the resumption of AW 139 Helicopter A7-GHC flights for our operations.
"
end quote:
ahhhh, the gentle glow of fire round yer ringpiece from sunshine being blown up yer hoop . .
I realise Spinwing is happy enough to go to work in one so have no real issues with doing the same, I just _wish_ they didn't treat us like 3 year olds.
Official line from company "Mr Manufacturer has made it all better"
Unofficial line used by rigpigs "spent _just_ enough money to get away with it . ."