# NTSB NYC87LA267: Grumman AA-5A, N9772U, Irwin, PA, September 26, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 26, 1987, 16:00 local (20:00 UTC)
- Place: Irwin, PA
- Coordinates: 40.319602, -79.690322 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=40.3196&lon=-79.6903&mi=10
- Phase of flight: [Taxi](https://openairdocs.org/ntsb-phases/250) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report May 26, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 30741
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC87LA267
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/30741/pdf
- Page: https://openairdocs.org/ntsb/NYC87LA267

## Sequence of events

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

- Loss of control - on ground/water, taxi - to takeoff
  - directional control - not maintained, pilot in command (cause)
- On ground/water collision with object, taxi - to takeoff
  - object - tree(s)

## Analysis

DURING TAXI OPERATION, THE PILOT LOST DIRECTIONAL CONTROL OF THE AIRCRAFT AND IT STRUCK A TREE STUMP WHICH WAS LOCATED TO THE SIDE OF THE RUNWAY. THE AIRCRAFT THEN CONTINUED TO ROLL ABOUT 500 FEET OFF THE RWY WHERE IT CAME TO REST WITH SUBSTANTIAL DAMAGE.

## Aircraft

- Registration: [N9772U](https://openairdocs.org/deregistered/N9772U-2012-09-12), registration cancelled 2012-09-12, S/N AA5A0172, built 1976 (OpenAirDocs)
- Reported make and model: GRUMMAN AA-5A
- Registry model: [Grumman American Avn. AA-5A](https://openairdocs.org/model/grumman-american-avn-aa-5a) (registry code 3960106) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: AA5A0172
- Engines: LYCOMING O-320-E2G 150 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Robert D. Milligan
- Registered owner: Robert D Milligan
- Airworthiness certificate: Standard, Normal
- Airport: 31D, Inter County, runway 9, 1,880 × 130 ft, grass/turf

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 52; private; airplane ratings: single-engine land; medical: class 3, expired; flight hours: 350 total

## Weather

- Conditions: Visual (VMC), Day

## 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 19870926057429A](https://openairdocs.org/incident/19870926057429A), Sep 26, 1987: Gulstm AA5A, Irwin, PA, Substantial damage. While taxiing struck a tree stump. Failed to close throttle, rolled off end of runway into ditch.

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.