Glider in near miss with US fighter jets over Downham Market
US fighter jets may have come as close as 50ft (15m) to a glider as they flew to land at an airbase in Suffolk, a near-miss inquiry has found.
The four F-15s were over Downham Market, Norfolk, heading towards RAF Lakenheath when the incident happened.
The jets were warned by air traffic control and the lead F-15 pilot took evasive action as they saw the glider.
The UK Airprox Board said the glider and the jets did not have compatible electronic warning systems.
These allow communication between planes when they move close to each other.
The Nimbus glider had taken off from Marham and was on its way to March on 17 April when the pilot spotted the jets "closing range", said the Airprox Board report.
"The pilot considered the best action to descend and pass below the aircraft, and initiated a descent by opening the airbrakes and increasing speed," the report said.
The pilot "didn't see a reaction from the other aircraft to suggest the glider had been seen, but the descent was enough to remove the collision risk".
"When they passed there was no lateral separation but the pilot estimated the closest jet passed overhead with 50-100ft (15-30m) vertical separation," the report said.
The F-15 lead pilot estimated the aircrafts passed within 500ft (150m) of each other.
The board said in its conclusion that fast moving jets can be perceived as closer than they are. It rated the degree of risk as B, its second highest rating.
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