Aircraft Information
The aircraft, serial number 34-7250309, was manufactured in 1972. It had an empty mass of 1260 kg and a maximum takeoff mass of 1905 kg. The airframe had accumulated 9,136 flight hours. It was equipped with two Lycoming IO-360-C1E6 engines and two-blade metal propellers, each with 1,166 hours since new. The last 100-hour inspection was certified on 6 July 2021, and the airworthiness review certificate (ARC) was renewed on 26 March 2021 with one-year validity. The aircraft featured a retractable landing gear actuated by a hydraulic system with an electric pump.
Flight and Personnel
The instructor, aged 37, held a CPL(A) license issued by AESA on 30 January 2009, with valid FI(A), CRI(A), MEP(land), SEP(land), and IR(A) ratings. He had 1,605 total flight hours, of which 517.5 were as an instructor. The student pilot, aged 30, held a Class 1 medical certificate valid until 19 September 2021 and had 197 flight hours.
Event Sequence
The flight departed Requena at 15:30 local time to practice maneuvers for the multi-engine rating, including turns, slow flight in landing configuration, and stalls. After 45 minutes, they returned to the aerodrome. During an engine failure simulation, the student performed a go-around. Subsequently, a circuit was flown for a touch-and-go. The landing gear was extended at 120 mph and 3,100 ft altitude, with three green lights confirmed. Flaps were selected at appropriate speeds. After landing, flaps were retracted and takeoff power was applied. Approximately two seconds later, the nose of the aircraft dropped and the aircraft began to slide on the runway. The instructor took control, applied brakes gently, and brought the aircraft to a stop. Fuel and electrical systems were shut down, and both occupants evacuated unaided.
Damage and Injuries
The primary damage consisted of both propellers striking the pavement, resulting in deformations, and damage to the lower fuselage. No other damage was reported. Both the instructor and student remained uninjured.
Probable Cause
The investigation determined that the incident was caused by an uncommanded retraction of the nose landing gear, due to the failure of the locking bolt tensioner of the drag brace that holds it in the extended position.