Red Arrows Hawk jet at RAF Scampton, Lincolnshire, November 8, 2011. Picture: Press Association.
A Red Arrows pilot died after the parachute on his ejection seat failed to deploy in an event that would only happen "once every 115 years", a court has heard.
Flight Lieutenant Sean Cunningham suffered fatal injuries when his parachute on the Mark 10B ejector seat did not deploy, causing the South African-born airman to fall 200ft. He later died in hospital.
The parachute on the Mark 10B ejector seat did not deploy and the South African-born airman fell 200ft before he later died in hospital.
But the defence submissions for Martin-Baker Aircraft Company Ltd said an assessment by the Ministry of Defence (MoD) was that such an incident would happen only once in more than 100 years.
The court was also told that the Middlesex-based firm had a "good system" in place and it "just failed in this instance".
Martin-Baker Aircraft Company Ltd admitted failing to ensure the safety of non-employees in connection with the 35-year-old's death at a hearing on January 22.
On Monday, Lincoln Crown Court heard how the company has already agreed to pay £550,000 in prosecution costs as a result of the guilty plea.
Although the company pleaded guilty, it disputes some of the allegations made by the prosecution.
Opening the case against the firm, prosecutor Rex Tedd QC said: "The defendant admits that the breach of duty was a substantial or significant cause of the death of Flight Lieutenant Sean Cunningham."
Mr Tedd said the company had a duty to "ensure none of the pilots" were exposed to a health and safety risk.
He continued: "The defendant accepts that the risk persisted for a long period.
"If the pilot was ejected from the Hawk aircraft, two shackles would not release from one another and would jam together and the main parachute would not deploy.
"The pilot would be several hundred feet in the air and there could only be one result of that, and that is the pilot's death."
Richard Matthews, defending, said:
"The company accepts its responsibility for the significant contribution and failings it has made in the death of Lieutenant Cunningham.
"Nobody can convey the sadness, regret and the apology on behalf of the company and all those who stand behind it. I know you will accept that it is enormous.
"The ethos of the company from its inception is for the ejection seat to be a lifeboat that should operate effectively in every situation."
Mr Matthews added: "In the 1990s, what Martin-Baker had in place was a good system and it just failed in this instance.
"The MoD's assessment of the likelihood of a similar event such as this happening is that it would only happen once every 115 years."
In a statement released after the guilty plea, the company said: "It should be noted that this was an isolated failure relating to the tightening of a nut during maintenance procedures conducted by RAF Aerobatic Team (RAFAT) mechanics."
But the prosecution claims Martin-Baker Aircraft Company's position that Mr Cunningham's death was an isolated incident is "not accurate".
Mr Tedd added: "There was a risk to many pilots over a lengthy period. The defendant's failure was anything but isolated.
"Each pilot should have complete confidence in the ejector seat."
However, the court heard how the company had invented the ejector seat and "undoubtedly saved the lives of many pilots".
The firm describes itself on its website as a family-run business and "the world leader in the design and manufacture of ejection and crashworthy seats for nearly 70 years".
The court heard how Mr Cunningham's two greatest fears became a reality when he was ejected from the stationary aircraft.
Despite the Hawk undergoing a routine inspection in October, the pilot still fell from a considerable height and sustained injuries that were "unsurvivable".
Mr Tedd said:
"Sean's two biggest fears in life were being ejected from an aircraft and the injuries that would be sustained, and dying at a young age. He was to tragically experience both of these."
"This tragic incident was the eventuation of the risk of the shackles jamming at low speeds."
The Honourable Mrs Justice Carr adjourned sentencing until Friday, February 23.