# NTSB BFO93LA108: Burkhart Grob Speed Astir II, N164SS, Chester, VT, July 4, 1993

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 4, 1993, 13:00 local (17:00 UTC)
- Place: Chester, VT
- Location: 43.2692° N, 72.5963° W: Placed by OpenAirDocs: center of Chester, VT, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=43.2692&lon=-72.5963&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report May 17, 1994
- Report: Approved by Office Director
- NTSB case key (mKey): 8782
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=BFO93LA108
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/8782/pdf
- Page: https://openairdocs.org/ntsb/BFO93LA108

## Probable cause

THE PILOT'S INADEQUATE INFLIGHT PLANNING AND AN IN FLIGHT ENCOUNTER WITH A DOWNDRAFT WHILE ON FINAL APPROACH.

## Sequence of events

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

- In flight encounter with weather, approach - vfr pattern - final approach
  - weather condition - downdraft (cause)
  - in-flight planning/decision - inadequate, pilot in command (cause)
- In flight collision with object, maneuvering - turn to landing area (emergency)
  - object - tree(s)

## Analysis

THE PILOT REPORTED THAT HE ATTEMPTED TO RETURN TO THE AIRPORT AFTER A LOCAL SOARING FLIGHT.  HE ENCOUNTERED A 'SUDDEN HEAVY SINK' AND IMPACTED TREES NEAR A FIELD LOCATED ABOUT TWO MILES FROM THE AIRPORT.

## Factual narrative

On July 4, 1993, about 1300 hours eastern daylight time, N164SS, a Grob Speed Astir II glider, registered to Louis Groundal, Newtown, Connecticut, was destroyed after impacting trees during landing near Chester, Vermont.  The certificated private pilot, the sole occupant, was not injured.  Visual meteorological conditions prevailed and a flight plan was not filed.  The local personal flight originated from Springfield, Vermont, and was conducted under 14 CFR 91.

According to the pilot;

"After about one hour of soaring, attempts to return to airport to land [were] hampered by sudden heavy sink.  Terrain consisted of trees and [lacked] appropriate off field landing sites, except a pond and one small very rough field (1.5 to 2 miles from airport).  Attempted to land glider in field, but on final approach heavy sink put glider in a tree near the edge of the field."

No mechanical malfunctions were reported.

## Aircraft

- Registration: [N164SS](https://openairdocs.org/deregistered/N164SS-1993-11-16), registration cancelled 1993-11-16, S/N 4020 (OpenAirDocs)
- Reported make and model: Burkhart Grob SPEED ASTIR II (SPEED ASTI)
- Registry model: [Burkhart Grob Flugzeugbau SPEED ASTIR II](https://openairdocs.org/model/burkhart-grob-flugzeugbau-speed-astir-ii) (registry code 1660302) (OpenAirDocs)
- Category: Glider
- Serial number: 4020
- Airframe hours: 220
- Engines: unknown
- Damage: Destroyed
- Flight: Personal, Part 91
- Operator: Louis Groundal
- Registered owner: Louis Groundal
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, September 12, 1992, 64 hours before
- Departed: VSF, SPRINGFIELD, VT
- Destination: VSF
- Airport: VSF, Hartness State

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 59; private; medical: unknown, unknown; seat: front; flight hours: 251 total, 63 in this make and model, 233 as pilot in command, 55 in the last 90 days, 20 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 340° at 10 knots
- Visibility: 25 statute miles
- Lowest ceiling: none
- Temperature: 81 °F, dew point 54 °F
- Altimeter: 29.00 inHg
- Observed at: LEB, 30 nm away

## 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 19930704021939A](https://openairdocs.org/incident/19930704021939A), Jul 4, 1993: Springfield, VT, Destroyed. Unable to return to airport due heavy sink rate. Struck trees trying for a small field.

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.