Now we all know where the fuel tank bladder AD comes from:
accident report
SUMMARY
2010060
Accident
14 August 2010, approximately 12.30 hours Stroe
D-HNOC
Robinson R44
Helicopter
During a positioning flight, both ground handling wheels were left attached to the helicopter. While hover taxiing before landing, the left ground handling wheel fell from the aircraft. The right ground handling wheel, however, was still attached to the right skid with its lifting handle pointing downwards. When the lifting handle hit the ground, the helicopter pivoted over to the left, the tail hit the ground and the tail, including the tail rotor, broke off. The helicopter became uncontrollable and came to a standstill lying on its side. The pilot suffered no injuries. The helicopter was damaged beyond repair.
D-HNOC was equipped with a single-walled aluminum fuel tank. This tank has proved to be vulnerable to post-accident fuel leaks and fires in other R44 accidents. To improve the R44 fuel system’s resistance to a post-accident fuel leak and possible fire, the helicopter manufacturer issued R44 Service Bulletin SB-78 (see Appendix C) on 20 December 2010. This bulletin requires R44 and R44 II helicopters with single-walled aluminum fuel tanks to be retrofitted with bladder- type tanks. With this modification the tank consists of a metal outer tank and a rubber inner tank which makes it double-walled and less vulnerable to fuel leaks and fire in the event of disruption of the outer tank. The SB states that compliance should be “as soon as practical but no later than 31 December 2014.”
