Engineering news
Ejector seat manufacturer Martin Baker has been heavily criticised by a coroner after an inquest into the death of a Red Arrows pilot.
Central Lincolnshire coroner, Stuart Fisher, criticised Martin Baker for a "serious failure of communication" relating to known risks associated with over-tightening of crucial nuts and bolts which could "hinder or prevent" the deployment of the main parachute. He also described safety pins in the ejector seat's handle as "useless".
Flight Lieutenant Sean Cunningham, 35, was killed when he unintentionally activated the ejector seat on his Hawk T1 aircraft during pre-flight checks and was ejected 220ft in the air on November 8 2011. He remained attached to his seat and fell unrestrained by the main parachute to the ground. He suffered non-survivable injuries, in particular to his brain and cardiovascular system, as a consequence of the high velocity impact with the ground.
Following a three week inquest, coroner Stuart Fisher, said the main parachute had not opened and Flt Lt Cunningham had remained in the seat because a shackle had jammed in the seat's mechanism.
The coroner said that the over-tightening of nuts and bolts in the mechanism of the seat
could cause the main parachute not to deploy properly. He added that despite being aware of these issues since 1990, Martin Baker had failed to warn the Ministry of Defence, when it had warned over customers.
Fisher said: "There was a very serious failure of communication by Martin Baker in my view. It is unexplained by the evidence. It seems there is no logic to warn and inform some but not others."
The inquest heard that both Flt Lt Cunningham and some 19 separate checks on the Hawk aircraft carried out in the four days leading up to the incident had failed to identify that the seat firing handle was unsafe and a safety pin incorrectly placed.
However, Mr Fisher said tests had showed that the pin could be inserted into the MK 10 seat even when it was in an unsafe position, giving the impression to RAF personnel that the seat was safe. He described the safety pin that goes through the firing handle as "entirely useless" and said its presence was "likely to mislead".
Mr Fisher recorded a narrative verdict, which does not attribute the cause of death to a named individual. He said he was satisfied that substantial improvements had been made to the ejector seat system since the incident
Martin Baker said: "The ejection seat is qualified to save life on a ground level ejection. On this occasion, uniquely and in the entire history of Martin Baker, it failed due to a shackle bolt being too tight. This prevented the main parachute from deploying.
"In light of this incident, lessons have been learned and we have taken steps to alert all our customers worldwide who still use this type of seat, of the risk of over-tightening the shackle.
"Furthermore our designers, working closely with military experts, have developed a new type of shackle bolt and firing handle housing, which both Martin Baker and the military authorities consider will prevent the reoccurrence of the circumstances that led to this tragic accident.