# NTSB SEA93LA216: Let Blanik L-13, N52AS, Clinton, MT, September 26, 1993 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 26, 1993, 16:00 local (22:00 UTC) - Place: Clinton, MT - Coordinates: 46.610729, -113.590667 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=46.6107&lon=-113.5907&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report September 26, 1994 - Report: Approved by Office Director - NTSB case key (mKey): 41781 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA93LA216 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41781/pdf - Page: https://openairdocs.org/ntsb/SEA93LA216 ## Probable cause TOTAL FAILURE OF THE TOW EQUIPMENT. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - On ground/water collision with object, landing - roll - object - airport facility - glider launch/tow equipment - failure,total (contributing factor) - directional control - not possible, pilot in command (cause) ## Analysis DURING A SECOND TOW ATTEMPT, THE TOW ROPE BROKE FOR THE SECOND TIME. THE PILOT PULLED THE LEVER TO RELEASE THE ROPE, HOWEVER, THE ROPE DID NOT RELEASE. DURING THE LANDING ROLL, THE MAIN LANDING GEAR LANDED ON THE ROPE AND THE GLIDER VEERED TO THE RIGHT. THE GLIDER CONTINUED TO THE SIDE OF THE AIRSTRIP AND COLLIDED WITH A STATIONARY RUNWAY BORDER CONE BEFORE THE PILOT WAS ABLE TO REGAIN CONTROL AND MANEUVER THE GLIDER BACK ON THE AIRSTRIP. ## Factual narrative On September 26, 1993, at 1600 mountain daylight time, a Blanik L-13, N52AS, collided with a runway border cone after the takeoff was aborted, at Clinton, Montana. Visual meteorological conditions prevailed at the time and no flight plan was filed for the local flight. The glider was substantially damaged and the certificated private pilot was not injured. The pilot reported during a telephone interview and subsequent written statement that during the first attempted takeoff the tow rope broke a few feet in front of the glider. The pilot released the broken rope and made a successful landing. The rope was repaired and a second tow was attempted. During the tow, just after liftoff, the rope broke again approximately 20 feet in front of the glider. The pilot pulled the release lever and thought that the rope released, however, the rope did not. The pilot aborted the takeoff and attempted to land on the runway. During the landing roll, the pilot stated that the main wheel landed on the rope and the glider veered to the right. The glider continued to the side of the airstrip and collided with a stationary runway border cone before the pilot was able to regain control and maneuver the glider back to the airstrip. The accident was not reported by the pilot until October 5, 1993. ## Aircraft - Registration: [N52AS](https://openairdocs.org/aircraft/N52AS), registered now, S/N 027056, built 1977 (OpenAirDocs) - Reported make and model: LET BLANIK L-13 (BLANIK L-1) - Registry model: [Let BLANIK L-13](https://openairdocs.org/model/let-blanik-l-13) (registry code 1360306) (OpenAirDocs) - Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs) - Category: Glider - Serial number: 027056 - Engines: unknown - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Hellgate Soaring Society - Registered owner: North Idaho Soaring Assoc - Airworthiness certificate: Standard, Normal - Airport: 25S, Clinton ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 61; private; seat: rear; flight hours: 14 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 200° at 12 knots, gusting 15 - Visibility: 25 statute miles - Lowest ceiling: none - Temperature: 75 °F ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19930926037719A](https://openairdocs.org/incident/19930926037719A), Sep 26, 1993: Let L13BLANIK, Clinton, MT, Substantial damage. Tow rope broke second time. Tow plane aborted. Landed on tow rope causing glider to veer off runway. Hit border cone ## Other investigations on N52AS (1) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB SEA97LA194](https://openairdocs.org/ntsb/SEA97LA194), Aug 19, 1997: Let Blanik L-13 (N52AS), Hamilton, MT, substantial damage. Probable cause: The pilot's excessive speed taxispeed and failure to maintain wing clearance from a taxiway sign. From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.