# NTSB SEA01LA058: Avia Stroitel AC-5m, N1635M, Bozeman, MT, March 4, 2001

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: March 4, 2001, 13:00 local (20:00 UTC)
- Place: Bozeman, MT
- Coordinates: 45.770256, -110.930267 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=45.7703&lon=-110.9303&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed, report July 30, 2001
- Report: Approved by Office Director
- Parties: Helena FSDO
- NTSB case key (mKey): 51859
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA01LA058
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/51859/pdf
- Page: https://openairdocs.org/ntsb/SEA01LA058

## Probable cause

the pilot's improper remedial action upon experiencing the unexpected opening of the aircraft's canopy during the initial part of the takeoff climb. Factors include his attention being diverted to the open canopy, his failure to use a checklist to ensure he did not miss any critical pre-takeoff actions, his failure to lock the canopy, and the unintentional opening of the canopy after liftoff.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- In flight collision with terrain/water, takeoff - initial climb
  - diverted attention, pilot in command (cause)
  - remedial action - improper, pilot in command (cause)
  - checklist - not used, pilot in command (contributing factor)
  - window,canopy - not secured (contributing factor)
  - window,canopy - open (contributing factor)

## Analysis

Prior to takeoff in a powered glider, the pilot opened and closed the canopy a number of times in order to communicate with members of his ground crew. When he was given clearance for departure, he closed the canopy one last time, but inadvertently did not get the latching mechanism fully engaged. After liftoff, as the aircraft climbed to about 30 feet above the runway, the canopy unexpectedly swung open. The pilot's attention was then momentarily diverted to the open canopy, and when he looked back toward the front of the aircraft, it was just about to impact the surface of the runway in a nose-down attitude. It was later determined that he had not reviewed his checklist just prior to departure to ensure that he had accomplished all critical items.

## Factual narrative

On March 4, 2001, approximately 1300 mountain standard time, an experimental/exhibition Avia Stroitel AC-5m motorized glider, N1635M, impacted the runway during takeoff from Gallatin Field, Bozeman, Montana. The commercial pilot, who was the sole occupant, received serious injuries, and the aircraft, which was owned and operated by Russia Sailplanes, Inc., sustained substantial damage. The local 14 CFR Part 91 flight was being operated in visual meteorological conditions. No flight plan had been filed.

According to the pilot, this was the first flight of this make and model aircraft within the United States. Witnesses reported that when the aircraft, which was taking off under its own power, reached about 30 feet above the runway surface, the canopy flipped open. Soon after the canopy came open, the aircraft pitched up and then nosed into the runway surface.  According to the pilot, he opened and closed the canopy a number of times while waiting for departure in order to communicate with his ground crew. When he closed the canopy the last time, he did not get it fully latched, and a couple of seconds after the aircraft lifted off, the canopy was sucked open. The pilot's attention was  then momentarily diverted to the canopy, which rotates to the side upon opening. When he again looked back straight ahead, the aircraft was just about to impact the runway in a nose-down attitude. It was later determined that the pilot had not reviewed his checklist just prior to departure in order to ensure that he had not missed any critical items.

## Aircraft

- Registration: [N1635M](https://openairdocs.org/deregistered/N1635M-2022-09-15), registration cancelled 2022-09-15, S/N 003, built 2001 (OpenAirDocs)
- Reported make and model: Avia Stroitel AC-5m
- Registry model: [Avia Stroitel AC-5M](https://openairdocs.org/model/avia-stroitel-ac-5m) (registry code 05610QZ) (OpenAirDocs)
- Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs)
- Category: Glider, amateur-built
- Serial number: 003
- Airframe hours: 5
- Engines: Zanzottera MZ-35 27 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Bill Ard
- Airworthiness certificate: Special, Experimental (Special)
- Departed: Bozeman, MT
- Airport: BZN, Gallatin Field, runway 30, 9,500 × 150 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 54; injuries: serious; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; last flight review August 23, 2000; seat: single; flight hours: 2,400 total, 0 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 32 °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 20010304002439A](https://openairdocs.org/incident/20010304002439A), Mar 4, 2001: Bozeman, MT, No damage. (-23) During a powered take-off on runway 30 at bzn, the canopy opened. The pilot failed to latch the canopy prior to take-off. The glider pitched up to…

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.

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