Flight Sequence
A commercial pilot was undergoing an initial orientation flight in a Lear 35A after completing ground school. The flight proceeded to an airport for touch-and-go practice following airwork. After touchdown, the commercial pilot deployed reverse thrust. When the flight instructor called for the go-around, the commercial pilot stowed the thrust reversers and advanced the power levers for takeoff thrust. Upon applying power, the airplane became uncontrollable, departed the left side of the runway, and came to rest in a grassy area.
Thrust Reverser Operation
According to the flight instructor, the pneumatic thrust reversers installed on the airplane would not always deploy or stow simultaneously, even when initiated at the same time. The Federal Aviation Administration (FAA) stated that the flight manual supplement for the thrust reversers was not included in the airplane flight manual. This supplement contained a limitation prohibiting the use of reverse thrust during touch-and-go landings. It also included a caution not to advance the thrust levers until the IDLE and DEPLOY lights were extinguished.
Pilot Awareness and Actions
Both pilots reported they were looking outside and did not observe the thrust reverser lights. The commercial pilot stated he was unaware of the restriction on using reverse thrust in touch-and-go landings. The flight instructor reported being aware of the restriction but was not aware that the commercial pilot had initiated reverse thrust and did not expect it.
The aircraft came to rest in a grassy area adjacent to the runway after departing the left side.