The AAIB discovered the seat’s security pin was not totally put in and the beforehand disconnected harness chest strap caught on and inadvertently actuated the seat’s deal with.
An improperly inserted security pin after touchdown and a disconnected harness chess strap getting caught on the ejection seat deal with brought about the unintended ejection that killed T-6A Texan II teacher pilot on Could 13, 2024 at Sheppard AFB, Texas. An Accident Investigation Board (AAIB) report launched on Jun. 23, 2025, additionally noticed that unbuckling whereas nonetheless taxiing after touchdown was discovered to be a standard follow by some T-6A instructors, though correct pointers about when to disconnect from the seat are usually not offered.
The deceased teacher pilot, Capt. John Robertson, and the coed pilot, have been assigned to the eightieth Operations Help Squadron, and flew with the 89th Flying Coaching Squadron throughout the eightieth Flying Coaching Wing. Robertson was ejected practically 100 ft into the air and, since he was not linked to the parachute, crashed down by the roof of an plane sunshade.
Robertson handed away within the hospital the next day resulting from “non-survivable accidents,” stated a abstract of the AAIB report. The coed pilot didn’t eject and thus didn’t maintain accidents, safely stopping the plane and shutting it down.
The AAIB report famous Robertson’s “revered” standing among the many management, fellow instructors, and college students, including that he was additionally acknowledged because the Teacher Pilot of the Yr for 2023. He would additionally “spend additional time” on troublesome subjects with struggling college students to assist them succeed.
The eightieth Flying Coaching Wing, below the Air Training and Coaching Command (AETC), is a part of the Euro-NATO Joint Jet Pilot Coaching (ENJJPT) program, the world’s solely internationally manned and managed flying coaching program which is supposed to coach fight pilots for NATO. It contains contributors from 14 NATO member nations, together with america, Germany, Italy and Turkey.
The T-6A is a single-engine, two-seat main coach plane used to show primary flying expertise to college students within the Joint Major Pilot Coaching (JPPT) program for each the U.S. Air Drive and Navy. The T-6A was formally named the Texan II in 1997 when it entered service. The plane is provided with Martin-Baker US16LA ejection seats.

Security pin
AAIB investigators relied on bodily examination of the spot, the plane, proof recovered from the scene and several other trials on simulators to achieve their findings. The mishap flight was Robertson’s second sortie that day, whereas he was scheduled for just one instruction flight on the T-6A.
That is what the abstract of the AAIB report stated:
“The mishap was attributable to the teacher pilot failing to totally set up the ejection seat security pin through the after touchdown guidelines. Moreover, throughout taxi, the teacher pilot partially disconnected from the rear cockpit ejection seat system, together with the parachute. Throughout that technique of disconnecting from numerous connection factors to the ejection seat, the teacher pilot’s harness chest strap V-ring unknowingly received caught on and inadvertently activated the ejection seat management deal with, initiating the ejection sequence.”

The stated Texan II, tail 08-3915, landed on Sheppard AFB’s Runway 33R with the Mishap Teacher Pilot (MIP) Robertson within the rear seat and the Mishap Scholar Pilot (MSP), who was piloting the plane, within the entrance. Throughout taxi, upon clearing the runway, the MSP initiated the usual After Touchdown Guidelines, “together with verbal question-and-answer steps, with the MIP.”
This stage contains inserting the security pin into their ejection seats, when Robertson didn’t totally set up it in his personal seat. An skilled teacher interviewed by the AAIB talked about “he noticed pupil pilots improperly set up the security pin midway on a number of events.”
The board drew the conclusion concerning the improperly put in pin primarily based on the “elongation of the seat security pin gap on each the main floor of the housing and the entrance fringe of the ejection deal with.” The report additional provides “the elongation is barely doable if the pin was put in”, which “signifies the seat security pin was not less than partially put in through the ejection sequence.”
Ejection seat deal with actuation
Following the partial disconnection from the seat, Robertson “inadvertently actuated” the ejection deal with and was thrown from the plane, whereas remaining “partially linked to, and seated in, the ejection seat till computerized seat/pilot separation.” At this level the pilot and seat are supposed to separate, adopted by the parachute being deployed. Nonetheless, since Robertson had disconnected from his parachute, there was nothing to arrest his descent.

To find out the trigger behind the inadvertent activation of the ejection seat management deal with, AAIB investigators analyzed a number of eventualities, together with utilizing the T-6A simulator to “recreate chest strap positioning eventualities within the T-6A cockpit.” That recreation confirmed that disconnecting the harness chest strap brought about each the ejector snap and the V-ring “to hold from the pilot’s harness.”
Whereas reaching all the way down to disconnect the left leg restraint garter, the V-ring from the pilot’s harness chest strap “can unknowingly change into caught within the ejection seat management deal with.” Thus, whereas sitting again upright “the pilot can inadvertently actuate the ejection seat management deal with if the V-ring from the pilot’s harness chest strap is caught within the ejection seat management deal with and the seat security pin isn’t totally put in into the seat,” the report states.
Notably, the report famous that unbuckling and disconnecting from the “ejection seat connections whereas nonetheless taxiing, earlier than the aircraft comes to an entire halt, is a standard follow not solely with Robertson, who had achieved the identical in his first instruction flight that morning, but additionally amongst different instructors. “The After Touchdown Guidelines, Engine Shutdown Guidelines, and Earlier than Leaving Plane Guidelines within the T-6A Flight Guide don’t embody info on when to disconnect from the ejection seat,” says the AAIB.
