Capt. Lucas Gruenther, 31st Fighter Wing chief of flight safety, is pictured mountain climbing in Italy. Gruenther was killed in an F-16 crash in January. (Courtesy photo)
- Filed Under
An F-16 pilot was killed as he ejected during a night training mission in January off the coast of Italy, an Air Force investigation has found.
Capt. Lucas Gruenther, chief of flight safety for the 31st Fighter Wing at Aviano Air Base, flew as part of a formation of three F-16CMs and one F-16DM during training over the Adriatic Sea. The pilots, flying with the use of night vision goggles after a 7:03 p.m. takeoff, were forced to abandon their first training mission because of weather, and instead focused on two simulated bomb drops as a backup mission. The four jets broke into teams of two, and the first part of the mission was executed withoutany problems.
At 7:48 p.m. local time, about 45 minutes after takeoff, Gruenther flew a simulated drop followed by a “last ditch” defensive maneuver followed by recover maneuvers, which were intended to simulate the threat of a surface-to-air missile. Gruenther pulled his F-16 to the right and nose down. He rolled the plane to stabilize at about 150 degrees, banking to the left with his nose down 40 degrees. He continued to descend and roll, accelerating through 400 knots and 17,700 feet above sea level until the simulated missile overshot him. This is where he began to experience spatial disorientation, according to the report.
“CLAW 1 missile overshot,” he radioed to his team in the air.
Three seconds later: “CLAW knock it off, I’m spatial D.”
The phrase “knock it off” tells the wingman or aircrew to stop their engagements.
The maneuvers resulted in a 45 degree nose low, 90 degree left wing down attitude, according to the report.
The maneuvers resulted in visual and aural warnings, with caution lights blinking in the aircraft, along with the high rate of descent and airspeed.
“Look at the round dials, disregard the HUD,” Gruenther’s wing man said back, telling him to ignore the warnings on the jet’s heads-up display and focus on the instruments in his cockpit to help him get his bearings.
At 7:49:17, he rolled away from the horizon to fully inverted, his canopy pointing directly toward the ground, and pulled his nose to 70 degrees nose low toward the water, now flying 535 knots through 12,000 feet. One second later, he rolled right, trying to even up the jet.
“1 status your round dials,” the wingman asked, but Gruenther did not respond.
He continued to try to gain control, but finally believed he could not recover, and decided to eject.
At about 7:49:24 p.m., Gruenther ejected. His jet was at 7,066 feet, traveling 569 knots at a dive angle of 16 degrees and an 18 degree left bank.
He immediately lost his helmet. The ejection seat launched with a left yaw from the cockpit, and there was slack in Gruenther’s harness. All of that, combined with a snap back with the force of 40 Gs following drogue chute deployment, quickly resulted in the pilot’s death from severe head and neck trauma, according to the report.
The crash destroyed the F-16 at a loss of about $28.4 million.
“I find, by clear and convincing evidence, that the cause of the mishap was the mishap pilot’s failure to effectively recover from spatial disorientation, due to a combination of weather conditions, the MP’s use of [night vision goggles], the [aircraft’s] attitude and high rate of speed, and the MP’s breakdown in visual scan,” accident investigation board president Brig. Gen. Derek Rydholm wrote in his opinion of the report. “This led the MP to misjudge the imminent need to eject.”
Quickly after losing contact with Gruenther, his wingman radioed the base to declare an emergency and begin search and rescue. The Italian Air Force and Coast Guard began the search with five boats and a helicopter. The search lasted about three days, and included the use of a Navy P-3 Orion, an Air Force C-130J, American F-16s and the Italian Coast Guard, which recovered his remains on Jan. 31.
PROBLEMS WITH THE GEAR
The report details issues with the F-16’s ejection system and Gruenther’s gear, but stops short of saying they contributed to his death. The jet’s speed and positioning was within the performance envelope of the ejection equipment. However, he launched wearing the night vision goggles and a helmet-mounted cueing system, which could place a potentially fatal load on the pilot’s neck, the report states.
Upon ejection, the seat’s retraction reels retracted to unequal lengths: the left side strap protruded 3 inches from the back of the seat to the tip of the fitting, while the right strap protruded 4.5 inches. This meant that Gruenther was off center, to the left of the seat when the ejection rockets fired.
He experienced an approximately 15G downforce when his helmet came off in the initial wind blast. The seat left the jet on a left yaw, with another 10Gs of left lateral force. The drogue chute, designed to stabilize the seat for fast ejections, caused a 40G snap back to the right.
As part of the report, investigators reviewed inspection and maintenance records of the ejection equipment that “revealed several discrepancies,” but “there is no evidence to suggest these discrepancies were a factor in the mishap or MP’s death.”
The Flight Equipment Records Management System showed that a G-suit fit check had not occurred within 120 days as required. A time compliance technical order for an inspection of the G-suit’s water check valve was marked on the suit itself, but not in the suit’s records. The personnel locator beacon was tested as “battery well,” but not marked as such in records.
PICTURED HIM A GENERAL
Gruenther came from a military pedigree. He graduated from the Air Force Academy in 2003, taught pilots in Texas and had deployed to Afghanistan.
“Luc has wanted to be a pilot since he was a little boy,” his mother Romel Mathias said in a statement following his death. “And, he did everything he had to do to get there. That’s what he does with everything in his life. If he wants to do something, he finds a way to do it.”
His grandfather is Army Gen. Alfred Gruenther, who served as Supreme Allied Commander in Europe from 1953 to 1956.
The pilot planned to stay in the Air Force.
“He loves what he does,” Gruenther’s wife Cassy said in a statement after Gruenther‘s body was found. “He’s the kind of officer who knows the name of every maintainer out there on the flight line. I’ve always pictured him as a general one day, making a difference.”