What happened
On March 9, 2016, an L-23 Super Blanik glider, registration VT-GLK, was conducting a routine flight from the Glider Centre Pune. After a successful winch launch that reached an initial height of 300m, the pilot began soaring and reached an altitude of 1000m.
While flying toward Loni, approximately 9.18 km from the runway threshold, the aircraft encountered a severe downdraft. The pilot attempted to find rising air by changing direction several times, but the aircraft continued to sink rapidly. Realizing the runway was no longer reachable, the pilot attempted an emergency landing in an open field near a canal. During the touchdown, the glider's tailwheel became entangled in overhead electrical wires, causing the aircraft to spin and eventually crash into a stack of pipes. The pilot escaped the wreckage with only a minor injury to a finger.
The investigation
AAIB India examined the wreckage and the circumstances surrounding the flight. The investigation confirmed that the aircraft was airworthy and the pilot held a valid license with sufficient experience on the type. Investigators analyzed the flight path, noting that the pilot's attempt to search for updrafts led to a critical loss of altitude, which reduced the available time for decision-making.
Technical examination of the wreckage revealed that the tailwheel disintegrated upon impact with the wires, and the left horizontal stabilizer also struck the electrical lines. The investigation also looked into the pilot's use of the rudder, finding evidence of forceful deflection that likely induced a side-slip, increasing drag and further contributing to the sink rate.
Findings
- The pilot encountered a heavy downdraft that caused the glider to lose altitude rapidly.
- The pilot's decision to continue searching for lift rather than immediately planning a return to the airfield resulted in the loss of a safe altitude for decision-making.
- The selection of the emergency landing site was deemed unsafe and insufficient.
- The tailwheel became entangled in overhead electric wires, which acted as an arrestor and prevented the glider from sliding into the adjacent canal.
- There was a lack of formal Standard Operating Procedures (SOPs) at the Glider Centre Pune for handling such emergency situations.
- Local meteorological information was not formally obtained from a MET service prior to the flight, relying instead on visual assessment.
Safety action
- The DGCA has been advised to instruct gliding institutes to develop training manuals with an emphasis on emergency handling.
- Recommendations were made for clubs to implement SOPs for collecting and documenting meteorological data before daily flights.
- Instructors should provide more rigorous training regarding field selection and out-field landing procedures.