What happened
During an experimental flight operation known as 'Tip Tow,' a formation involving a Boeing EB-29A and two Republic EF-84D fighters experienced a catastrophic failure. The maneuver involved linking the wingtips of the fighter aircraft to the bomber to test towing capabilities. While the right-hand fighter successfully uncoupled after failing to receive electrical power from the bomber, the left-hand EF-84D successfully docked with the EB-29A in a locked position.
Once the aircraft were stabilized and the crew believed electrical power was being shared, the pilot engaged the automatic flight control system. This activation triggered an immediate and intense nose-up elevator command. The resulting pitch caused the fighter to roll violently toward the outer wing panel of the bomber. Although explosive bolts were deployed to jettison the fighter from the bomber, the separation was not completed before the collision occurred.
The impact caused the EF-84D to strike the outer wing of the EB-29A, leading to the destruction of the bomber's wing spar and the shearing off of the fighter's nose section. The structural damage caused the left wing of the EB-29A to fail, sending the bomber into a steep spiral that ended in a crash into Peconic Bay, Long Island. The fighter also crashed shortly after the collision. The accident resulted in 6 fatalities, including the pilot of the fighter and five crew members from the bomber.
Findings
- The activation of the autopilot system on the fighter aircraft caused an uncommanded hard nose-up movement.
- The timing of the explosive bolt deployment was insufficient to prevent the mid-air impact.