Safety: September 2008 Archives

Took a little longer than expected, but the FAA has finally come out with the airworthiness directive following the AAIB investigators' of the BA 777 crash at Heathrow. As far as I can see it follows the Boeing guidance which is already out.

The one extra bit is that it officially confirms that the FAA doesn't think Pratt & Whitney and General Electric-powered 777s are likely to be affected by the ice issue that is believed to have brought down BA038. So the AD covers only Rolls-Royce Trent-powered 777s.

I had a chance to talk to Boeing about what they're now recommending and why. Although Boeing are not saying so I understand that the various manufacturers suspect that the risk only applies to Trent-powered aircraft due to the design of the fuel/oil heating system which Pratt and GE don't have.

Boeing are investigating whether other Rolls-Royce-powered current and legacy models are at risk. Anecdotally I also understand that it's by no means certain that Trent-powered Airbus widebodies will be affected due to different fuel-tank designs. Anyway, below is what Boeing is telling operators.

Tucked away in today's interim report by the UK Air Accidents Investigation Branch on the BA Boeing 777 crash is the fact that Britain's beleaguered prime minister Gordon Brown was not responsible for making it happen.

I mention this because it is contrary to what you will read suggested in quite a few places on the web. It is pointed out that Brown was flying through Heathrow that day and it is claimed as a serious possibility that radio emissions from his motor entourage (a modestly British affair by the way) could have, well, I don't know, screwed up the engine controls or something. Don't ask me - wasn't my idea.

Anyhow, the AAIB tried frying the fuel and engine controls with bizarrely strong radio signals and failed. They also point out that the less robust nav and comms systems on the aircraft behaved normally throughout. So, with customary diplomacy, they conclude: "There is therefore no evidence to suggest that HIRF (high intensity radiated field) or EMI (electro-magnetic interference) played any part in this accident."

So basically it's just the economy he needs to worry about.

As happens once in a while, the investigators of the crash of BA038 at Heathrow back in January are rather coming to the conclusion that, despite the millions of comparable flights the industry has made, we don't know as much about a basic element of long-haul flight as we thought we did. The element in question being the potential for ice to form in fuel in-flight.