A Red Arrows pilot was killed today after being ejected from his aircraft while on the ground.
The RAF said a full independent inquiry was being launched into the incident at RAF Scampton in Lincolnshire.
The tragic accident came less than three months after another pilot with the world-famous aerobatics team, Flight Lieutenant Jon Egging, 33, was killed in an air show crash in Dorset.
Medical teams rushed to RAF Scampton, the base of the Red Arrows, after the incident at about 11am this morning.
The Lincolnshire and Nottinghamshire Air Ambulance airlifted the pilot to Lincoln County Hospital but his injuries were so severe that he could not be saved.
The Red Arrows completed their final display of the season in September and are carrying out their winter training at RAF Scampton.
Speaking at RAF Scampton, Group Captain Simon Blake said: "The pilot was ejected from the aircraft whilst the aircraft was on the ground.
"The director-general of the Military Aviation Authority is in the process of initiating a full and independent service inquiry to determine the cause of this tragic incident.
"It would be inappropriate to speculate on the cause of the incident until that inquiry is complete. The investigation will determine the facts.
"The pilot's next of kin have been informed. Our thoughts and prayers are with the pilot's family and friends at this difficult time."
The pilot will be named tomorrow.
The Red Arrows Hawk T1 jets could be seen lined up on the tarmac at a misty RAF Scampton after the accident. One of the aircraft had the front part of its canopy missing.
Flt Lt Egging crashed to his death on August 20 minutes after performing a display with the Red Arrows watched by his wife.
Eyewitnesses described seeing the aircraft flying low before smashing into a field and coming to a standstill with its nose in the River Stour near the village of Throop.
Hundreds of RAF servicemen and women joined the hugely popular pilot's family and friends at a packed memorial service in Lincoln Cathedral last week.
The RAF temporarily halted flying of all 126 of its Hawk T1 training jets while preliminary investigations were carried out into the cause of the earlier tragedy.
The Red Arrows have used the dual-control BAE Systems Hawk T1, which has a top speed of Mach 1.2, since 1979.
Hawk T1s are also used for training fast-jet pilots at RAF Valley in Anglesey, North Wales, and RAF Leeming, near Northallerton, North Yorkshire.
During winter training each Red Arrows pilot flies three times a day, five days a week, beginning with small formations of three or four aircraft, according to the team's website.
All members of the squadron change from their distinctive red outfits into green flying suits and overalls to mark the transition from performing displays to practising for the next season.
Every training sortie is filmed from the ground and discussed in minute detail once the pilots are back on the ground.
The Red Arrows aim to fly their first formation involving all nine aircraft in the team in March.