# NTSB BFO91LA070: Grumman AA5, N9599L, Oakland, MD, July 20, 1991

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: July 20, 1991, 14:45 local (19:45 UTC)
- Place: Oakland, MD
- Coordinates: 39.409976, -79.410049 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.4100&lon=-79.4100&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 2 serious
- Status: Completed, report August 13, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 11695
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=BFO91LA070
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/11695/pdf
- Page: https://openairdocs.org/ntsb/BFO91LA070

## Probable cause

THE PILOT'S FAILURE TO MAINTAIN ADEQUATE AIRSPEED WHICH RESULTED IN AN INADVERTENT STALL.

## Sequence of events

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

- Loss of control - in flight, approach - vfr pattern - final approach
  - airspeed - not maintained, pilot in command (cause)
  - stall - inadvertent, pilot in command (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE PILOT WAS GIVING A DEMONSTRATION FLIGHT TO THE PASSENGER WHO WAS A PROSPECTIVE BUYER.  DURING THE APPROACH TO THE AIRFIELD THE AIRPLANE COLLIDED WITH THE GROUND ABOUT 700 FEET SHORT OF AND ALIGNED WITH THE RUNWAY. THE ACCOUNTS OF THE PILOT AND PASSENGER WERE NOT ASCERTAINED; HOWEVER, RESCUE PERSONNEL REPORTED THE PILOT SAID THE AIRPLANE STALLED. AN EXAMINATION OF THE AIRPLANE DID NOT DISCLOSE EVIDENCE OF MECHANICAL MALFUNCTION. THE FLAPS WERE FULL DOWN.

## Aircraft

- Registration: [N9599L](https://openairdocs.org/deregistered/N9599L-2013-05-23), registration cancelled 2013-05-23, S/N AA5-0599, built 1974 (OpenAirDocs)
- Reported make and model: GRUMMAN AA5
- Registry model: [Grumman American Avn. AA-5](https://openairdocs.org/model/grumman-american-avn-aa-5) (registry code 3960104) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: AA50599
- Engines: LYCOMING O-320-E3G 180 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Operator: Daniel K. Barnhart
- Registered owner: Daniel K. Barnhart
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, October 30, 1990
- Departed: 2G4, OAKLAND, MD
- Destination: 2MD8, OAKLAND, MD
- Airport: 2MD8, Greater Gortner, runway 4, 2,000 ×  ft, grass/turf

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 44; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 158 total

## Weather

- Conditions: Visual (VMC), Day
- Wind: 220° at 4 knots
- Visibility: 3 statute miles
- Lowest ceiling: 4,000 ft broken
- Temperature: 91 °F, dew point 66 °F
- Altimeter: 30.00 inHg
- Observed at: MGW, 1 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 19910720028929A](https://openairdocs.org/incident/19910720028929A), Jul 20, 1991: Gulstm AA5, Oakland, MD, Destroyed. Stalled and crashed on short final thunderstorm near airport and report of windshear.

## Other investigations on N9599L (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 FTW75DPJ07](https://openairdocs.org/ntsb/FTW75DPJ07), Sep 30, 1974: Amer Avco AA5 (N9599L), Yukon, OK, substantial damage

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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