A coroner today slammed safety pins in an ejector seat as "useless" as he criticised a manufacturer for failing to warn the RAF of defects which led to the death of a Red Arrows pilot.

Flight Lieutenant Sean Cunningham, 35, was killed after he was accidentally ejected 220ft into the air from his Hawk T1 aircraft while on the ground at RAF Scampton on November 8 2011.

The South African born pilot 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, an inquest heard.

Recording a narrative verdict into the death today, Central Lincolnshire coroner Stuart Fisher criticised manufacturer Martin Baker for failing to inform the RAF of risks associated with the seat.

The inquest, held in Lincoln, heard that the ejection seat firing handle had been left in an unsafe position which meant it could accidentally activate the seat.

Mr Fisher said the safety pin mechanism was "entirely useless" and that it was "likely to mislead".

Tests of the MK 10 Martin Baker seat had showed that the safety pin could be inserted even when the seat was in an unsafe position; giving the impression the seat was safe, the coroner said.

However the coroner noted that the failure of the handle should not have proved fatal as the parachute should have opened when Flt Lt Cunningham was ejected.

Mr Fisher also 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.

Despite being aware of the risks since 1990, Martin Baker failed to warn the Ministry of Defence, the coroner said.

Mr Fisher said: "There was a very serious failure of communication by Martin Baker (the manufacturer) in my view. It is unexplained by the evidence. It seems there is no logic to warn and inform some but not others."

Lawyers acting for the family today confirmed it had secured an undisclosed settlement from the Ministry of Defence in December 2013 following a full admission of liability for the incident in July that year.

Speaking after today's verdict, Flt Lt Cunningham's father Jim said: "We still find it difficult to accept that so many people could have missed, between Sean's last sortie on Friday and the following Tuesday, what should have been obvious to those having a duty to ensure the safety of the seat, and we remain unconvinced as to that aspect of the coroner's finding.

"Nevertheless, we accept that how the seat firing handle came to be in a position where it could be inadvertently activated may never be fully understood.

"We welcome the conclusions of the coroner, which confirm what we knew all along, which is that Sean was blameless and his tragic death was preventable. We therefore welcome the coroner's recommendations, which we hope and pray will ensure that no family such as ours has to endure such a pointless and avoidable death."

Mr Fisher said that, on the day of the incident, a shackle jammed and stopped the main parachute from opening and Flt Lt Cunningham being separated from his seat.

The coroner said Martin Baker had failed to have or operate a "sufficient, coherent and robust process" to inform all those who need to be warned about the known risks associated with the over-tightening of nuts and bolts.

The RAF also came under some criticism from the coroner for failing to ensure that crews were aware that a pin could be in the seat firing handle but still unsafe.

RAF personnel had 19 opportunities to check the ejection seat firing handle, but did not notice it was in the unsafe position.

Mr Fisher said the RAF had failed to take "sufficient steps" to bring the risk to the attention of all the air and ground crew who worked on the aircraft.

However coroner noted that Flt Lt Cunningham, described as a highly regarded and experienced pilot, also missed that the seat firing handle was unsafe and the pin incorrectly placed.

The inquest heard that he was going through pre-flight routine checks when he unintentionally activated the ejector seat.

Referring to failures by the RAF, Mr Fisher said: "The RAF's failures in this respect resulted in the seat firing handle being left in an unsafe position between last sortie on November 4 and the morning of 8 November 2011 during which time the lives of numerous RAF personnel were put at risk as they carried out cockpit activity.

"Whilst the RAF demanded mandatory pin checks to be carried out on each and every interaction with the cockpit, the RAF's failure to draw to the attention of all air and ground crew that it was possible for the seat firing handle to be raised and for the safety pin to be inserted through the seat firing handle but above the housing meant that an unsafe pin position was easily capable of being interpreted as being in a safe position.

"The need for briefing on what to look out for, for specific caution and the need to do a housing specific check was insufficiently emphasised."

Mr Fisher made two recommendations following his findings.

These were that Martin Baker and the MoD reach a design solution in aircraft ejection seats to prevent the strapping in process impacting on the safety of the seat and that Martin Baker introduce a new process for the urgent distribution of safety information.

In a statement released after the inquest, Martin Baker Aircraft Limited, said: "On 8 November 2011, Flt Lt Sean Cunningham died when he inadvertently ejected from an RAF Hawk T1, the seat pan firing handle having been mistakenly left in an unsafe position.

"We would like to extend our sincere condolences to Flt Lt Cunningham's family and friends.

"Martin Baker is a family-owned company producing vital equipment for people doing a dangerous and important job. We take our responsibilities to these individuals very seriously and we are all deeply saddened by this terrible accident.

"The ejection seat is qualified to save life on a ground level ejection (zero-zero). On this occasion, uniquely and in the entire history of Martin Baker ejection seats using this particular feature, it failed due to a shackle bolt being too tight. This prevented the main parachute from deploying.

"We supplied the seat to Hawker Siddeley (now part of BAE Systems) in 1976. Since then, for the last 35 years, the seat has been used and operated by the RAF.

"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.

"Martin Baker is proud to be able to say that, since 1946, it has led the world in the design, development and manufacture of ejection seats. As of today's date these seats have saved 7,436 lives, seven in this month alone."

Speaking outside court, Jim Cunningham said: "Our son Sean died aged 35 doing what he loved, which was flying with the Red Arrows. From the age of 17, he had wanted nothing more than to join the Royal Air Force and serve his country, which he did with utmost pride and sense of duty.

"He served a number of tours in Iraq flying Tornados in close air support of coalition forces. "Sean's death was a tragedy which we hope the evidence revealed in this inquest will help to avoid in the future.

"We are very grateful to the coroner, Mr Fisher, for allowing a full exploration of how this tragic death occurred.

"We would also like to thank our wonderful and dedicated legal team, Tom Kark QC and Polly Dyer from QEB Hollis Whiteman and Keith Barrett from Irwin Mitchell, for helping us in testing the evidence presented to the coroner of this inquest, so as to reveal the full details and background leading up to Sean's death on November 8 2011."

The MoD also paid tribute to the pilot and said lessons had been learned.

Speaking outside court, Air Commodore Terry Jones, said: "The tragic loss of Flight Lieutenant Sean Cunningham at RAF Scampton in November 2011 is still keenly felt by the Royal Air Force, the Red Arrows and all of Sean's former colleagues.

"Our thoughts have always been and continue to be with his mother and father Monika and Jim and sister Nicolette and his extended family and friends. They remain in our thoughts and prayers as always.

"We are grateful to the Coroner for his thorough examination of the facts and to the preceding thorough inquiry conducted by the Military Aviation Authority. There have been a number of lessons for us and others to absorb and correct and we have made and will continue to make every effort to ensure that such a tragic accident cannot occur again. The Red Arrows in particular will be a stronger, safer and better team as a result.

"Sean had an enthusiasm for flying and life that endeared him to all. He was enjoying his second year with the Red Arrows as Red 5 and he had become a principal mentor for the new pilots.

"Sean's professionalism, flying skill, constant smile and boundless energy earned him the respect and admiration of all. His tragic accident has been a shattering blow to everyone on the team in particular.

"Now that the inquest into this tragic event has concluded it is time to reflect on what a wonderful man and pilot Sean was. We were extremely privileged to have known him and to have had him within our ranks."