What happened
On June 30, 2019, a SpiceJet Dash8 Q400, registration VT-SUM, was operating flight SG3722 from Bhopal to Surat when it experienced a serious runway excursion. During the approach to Runway 22, the aircraft encountered deteriorating weather conditions, including heavy rainfall and thunderstorms. While visibility had been 4000 meters earlier, it dropped to approximately 1200 meters shortly before landing.
As the aircraft approached the runway, the pilot flying (PF) disconnected the autopilot at 77 feet AGL, which was below the recommended 200 feet AGL for precision approaches. The aircraft performed an extended flare at 30 feet, resulting in a float period of approximately 15 seconds. Although the crew applied maximum reverse thrust and progressive braking, the aircraft could not decelerate sufficiently on the wet surface. The aircraft overshot the runway end, coming to a stop in the Runway End Safety Area (RESA), approximately 2t33 meters past the runway threshold. There were no injuries to the 43 passengers or 4 crew members on board.
The investigation
AAIB India's investigation examined the flight data, meteorological reports, and organizational safety structures. Investigators found that while the airport had not officially reported a contaminated runway, video evidence confirmed the runway was flooded with water at the time of landing. The investigation also scrutinized the airline's training and oversight protocols, specifically regarding its turboprop fleet.
Findings
- The primary cause of the excursion was a combination of the pilot's failure to execute a go-around despite deteriorating weather, a late touchdown caused by an extended flare, and the use of a lower flap setting which increased the required landing distance.
- The pilot flying failed to adequately assess the rapidly worsening environmental conditions.
- The autopilot was disengaged too late, preventing the crew from better adapting to the heavy rain.
- There was a lack of standardized runway surface condition reporting, which left the crew without precise information regarding braking action.
- The investigation identified systemic issues within the operator, including a lack of active flight monitoring for the Q400 fleet and inadequate oversight of training management.
- The crew's approach speed was higher than normal due to the reduced flap configuration.