# NTSB NYC87LA231: Cessna 172, N9425D, Islip, NY, August 11, 1987

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: August 11, 1987, 14:00 local (18:00 UTC)
- Place: Islip, NY
- Coordinates: 40.730331, -73.209526 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=40.7303&lon=-73.2095&mi=10
- Phase of flight: [Taxi](https://openairdocs.org/ntsb-phases/250) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 4 uninjured
- Status: Completed, report May 26, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 30718
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC87LA231
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/30718/pdf
- Page: https://openairdocs.org/ntsb/NYC87LA231

## Sequence of events

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

- Airframe/component/system failure/malfunction, taxi - from landing
  - hydraulic system,line - failure,total (cause)
  - landing gear,normal brake system - failure,total (cause)
- On ground/water collision with object, taxi - from landing
  - object - aircraft moving on ground
- On ground/water collision with object, taxi - from landing
  - object - aircraft moving on ground
  - brakes(normal) - not possible, pilot of other aircraft (cause)

## Analysis (aircraft 2)

AFTER LANDING ON AN INSTRUCTIONAL FLIGHT, CESSNA 172, N9425D, EXPERIENCED BRAKE FAILURE DUE TO A BROKEN HYDRAULIC FLUID LINE. N9425D ROLLED INTO ANOTHER CESSNA. BOTH AIRCRAFT RECEIVED SUSTANTIAL DAMAGE.

## Analysis (aircraft 1)

AFTER LANDING ON AN INSTRUCTIONAL FLIGHT, CESSNA 172, N9425D, EXPERIENCED BRAKE FAILURE DUE TO A BROKEN HYDRAULIC FLUID LINE. N9425D ROLLED INTO ANOTHER CESSNA. BOTH AIRCRAFT RECEIVED SUBSTANTIAL DAMAGE.

## Aircraft 1

- Registration: [N9425D](https://openairdocs.org/deregistered/N9425D-2026-02-23), registration cancelled 2026-02-23, S/N 172RG1156, built 1984 (OpenAirDocs)
- Reported make and model: CESSNA 172
- Registry model: [Cessna 172RG](https://openairdocs.org/model/cessna-172rg) (registry code 2072438) (OpenAirDocs)
- Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 172RG1156
- Airframe hours: 1247
- Engines: LYCOMING O-360-F1A6 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Registered owner: Mid Island Air Service
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, November 1, 1986, 5 hours before
- Departed: ISP, ISLIP, NY
- Airport: ISP, Islip, runway 33L, 5,186 × 150 ft, asphalt

## Aircraft 2

- Registration: [N4868N](https://openairdocs.org/aircraft/N4868N), registered now, S/N 18267425, built 1979 (OpenAirDocs)
- Reported make and model: CESSNA 182
- Registry model: [Cessna 182Q](https://openairdocs.org/model/cessna-182q) (registry code 2072732) (OpenAirDocs)
- Registry engine: [Continental O-470 series](https://openairdocs.org/engine/continental-o-470-series) (registry code 17026, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 18267425
- Airframe hours: 1100
- Engines: CONTINENTAL O-470U 230 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Red Neck Warbler Aviation Inc.
- Airworthiness certificate: Standard, Normal
- Airport: ISP, Islip, runway 33L, 5,186 × 150 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot, aircraft N9425D; age 23; commercial, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: right; flight hours: 1,653 total, 57 in this make and model, 1,534 as pilot in command, 313 in the last 90 days
- Pilot, aircraft N4868N; age 39; private; airplane ratings: single-engine land, single-engine sea; medical: class 2, valid medical--w/ waivers/lim; seat: left; flight hours: 140 total, 140 in this make and model, 100 as pilot in command, 20 in the last 90 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 360° at 10 knots
- Visibility: 15 statute miles
- Lowest ceiling: none

## FAA reports on this event (2)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19870811048751A](https://openairdocs.org/incident/19870811048751A), Aug 11, 1987: Cessna 172RG, Islip, NY, Substantial damage. Brakes failed as aircraft turned off runway onto taxiway, struck a holding acft N4868N. Found broken hydraulic line
- [Accident 19870811048752A](https://openairdocs.org/incident/19870811048752A), Aug 11, 1987: Cessna 182, Islip, NY, Substantial damage. While waiting on taxiway for clearance to ramp, was struck by N9425D that had turned off runway. Had brake failure.

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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