# NTSB ATL86FA041: Mooney M20K, N231A, Langhorne, PA, December 15, 1985

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: December 15, 1985, 17:20 local (22:20 UTC)
- Place: Langhorne, PA
- Coordinates: 40.170429, -74.909484 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=40.1704&lon=-74.9095&mi=10
- Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 6915
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL86FA041
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/6915/pdf
- Page: https://openairdocs.org/ntsb/ATL86FA041

## Sequence of events

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

- Undershoot, approach - vfr pattern - final approach
  - light condition - dark night (contributing factor)
  - landing lights - not used, pilot in command (contributing factor)
  - procedures/directives - not followed, pilot in command (cause)
  - proper glidepath - not followed, pilot in command (cause)
  - clearance - not maintained, pilot in command (cause)
- In flight collision with object, approach - vfr pattern - final approach
  - object - wire,transmission(marked) (contributing factor)
  - altitude - below, pilot in command (cause)
- In flight collision with terrain/water, approach - vfr pattern - final approach

## Analysis

ACFT COLLIDED WITH MARKED BUT UNLIGHTED TRANSMISSION LINES 670 FT FM RWY THRESHOLD. THE LINES ARE 81 FT ABOVE THE THRESHOLD ELEVATION AND ARE MARKED BUT UNLIGHTED. THEY ARE ALSO 1193 FT FROM THE DISPLACED THRESHOLD. THE PILOT DID NOT HAVE A CURRENT MEDICAL OR PILOT CERTIFICATE. INSULIN AND CHLOROTHIAZIDE WERE FOUND IN THE PILOTS PERSONAL EFFECTS WITNESSES DID NOT RECALL SEEING ACFT LDG LIGHTS DISPLAYED PRIOR TO THE LINE COLLISION ALTHOUGH EVIDENCE OF ELECTRICAL AVAILABILITY WAS FOUND.

## Aircraft

- Registration: [N231A](https://openairdocs.org/deregistered/N231A-1996-04-04), registration cancelled 1996-04-04, S/N 250645 (OpenAirDocs)
- Reported make and model: MOONEY M20K
- Registry model: [Mooney M20K](https://openairdocs.org/model/mooney-m20k) (registry code 5870220) (OpenAirDocs)
- Category: Airplane
- Serial number: 25-0645
- Airframe hours: 1566
- Engines: CONTINENTAL TSIO-360-GB 210 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Jeffery M & Barbara Adelglass
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, October 26, 1985, 78 hours before
- Departed: ACY, ATLANTIC CITY, NJ
- Airport: N54, Buehl Field, runway 24, 3,125 × 49 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 50; student; medical: expired; seat: left; toxicology performed

## Weather

- Conditions: Visual (VMC), Night/dark
- Wind: 210° at 8 knots
- Visibility: 7 statute miles
- Lowest ceiling: none
- Temperature: 32 °F, dew point 19 °F
- Altimeter: 30.00 inHg
- Observed at: PNE, 8 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 19851215061959A](https://openairdocs.org/incident/19851215061959A), Dec 15, 1985: Mooney M20K, Langhorne, PA, Substantial damage, 1 fatal. Too low on night landing. Collided with unlighted power lines. Pilot had diabetes and severe heart disease.

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.