MUMBAI: Competing theories about what triggered AI 171 to crash have generated a brand new set of attainable explanations. Amongst them is the query that since Boeing’s 787 changed typical pneumatic and hydraulic techniques with electrical techniques – to make the plane lighter to save lots of gas and upkeep prices – whether or not there was {an electrical} system failure.There is no consensus. However as pilots proceed to search for solutions, electrical system failure has emerged as one of many newest makes an attempt, by some, to clarify the tragedy.All theories begin from the premise that the lone survivor heard a increase, which can point out a single engine failure. That would not have triggered a contemporary plane to crash? So what else went mistaken? Did the second engine fail or was it one thing else?Twin engine failures are uncommon occasions: seven cases have been recorded previously seven a long time, the world over. The causes had been chook strikes (US Airways Hudson river touchdown in 2009), mistaken engine shutdown (1989 British Midland flight 92, technical points led to the mistaken shutdown of the nice engine) and gas contamination or hunger. The potential for chook strike has been largely dominated out in case of the AI 171 crash on June 12.However B787 is a “more-electric” plane. So, pilots and consultants are taking a look at this accident otherwise. A senior B787 commander mentioned: “The increase sound signifies it is extremely possible one of many two engines had a partial or full shutdown.” However what occurred after that?Did the pilots shut off the nice engine, like in an earlier crash? However many pilots mentioned that the method of shutting off gas to the malfunctioning engine begins solely at 400 ft and it takes a while to execute – the plane had crashed earlier than that may very well be accomplished.Did the “startle impact” – pilots’ involuntary response to a sudden, surprising occasion – make the pilots overlook they needed to retract the touchdown gear? Or, had been the flaps (gadgets on a wing’s trailing edge that, when lowered, generate raise at decrease speeds) retracted as an alternative of the touchdown gear? However because the B787 commander mentioned: “Even when that had occurred, with one engine intact, the plane may have climbed out safely to return again and land”.It is the both-engines-down state of affairs that is making some pilots consider electrical failure. “Preliminary assessments point out that sooner or later through the take-off a number of VFSGs (Variable Frequency Starter Mills: these begin engines and supply predominant electrical energy throughout flight) might have failed or turn into electrically remoted, leading to partial or complete lack of engine management,” mentioned a senior Airbus commander, who has flown Boeing wide-body plane.