What happened
On March 6, 2009, the Saras Prototype PT2, an aircraft owned and operated by National Aerospace Laboratories, was conducting its 49th test flight. The mission was designed to evaluate various flight characteristics, including handling checks and simulated engine-out procedures. The crew, consisting of a pilot, co-pilot, and a flight test engineer, commenced the flight from HAL airport with the intent to perform engine shutdown and relight maneuvers at altitude.
Following a successful takeoff and initial handling checks, the crew performed a simulated single-engine approach. After completing the approach, the right engine was throttled up to match the left engine as the aircraft climbed back to 9000 feet. At approximately 10:00:40 UTC, following established test protocols, the left engine was shut down. Shortly thereafter, the crew initiated the procedure to relight the left engine at approximately 9200 feet.
During this engine relight phase, the aircraft experienced a sudden descent from 9200 feet to 7300 feet lasting roughly 13 seconds. During this period, radio contact with the flight test director became intermittent, and the telemetry link also began to fail. Although telemetry data indicated that the engine relight had been successful, the aircraft entered a continuous loss of altitude. Just ten seconds before the impact, the commander reported that the aircraft had departed from controlled flight. The Saras Prototype PT2 crashed near Sehsagirihalli, near Bidadi, at approximately 10:04 UTC. The impact and subsequent fire resulted in 3 fatalities.
Findings
Telemetry data recorded during the final moments showed that while the engine relight appeared successful in terms of ITT and fuel flow, the aircraft was in a state of uncontrolled descent. The aircraft's nose was found facing east, with the fuselage broken and the aircraft resting in an inverted position.