Cessna 172L accident near Aberdeen, Maryland, July 16, 1986
On July 16, 1986 at about 5:30 am local time, a Cessna 172L, registered N3933Q, was destroyed in an accident near Aberdeen, Maryland (Phillips Aaf airport). It was a public-use flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 16, 1986 · about 5:30 am local time
- Place
- Aberdeen, Maryland · Phillips Aaf · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 172L · all 172Ls on the register
- Registration
- N3933Q · no longer on the register · serial 60033
- Damage
- Destroyed
- Flight
- Public-use flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE PLT STATED THAT THE ENG BEGAN TO RUN ROUGH DURING FLT, THEN ALL AT ONCE, IT STARTED VIBRATING EXCESSIVELY. HE ATTEMPTED TO LAND AT THE PHILLIPS AAF, BUT THE ARPT WAS CLOSED & THE RWY LIGHTS WERE NOT ILLUMINATED. BY THE TIME HE SAW THE RWY, THE ACFT WAS NOT IN A POSITION TO LAND, SO HE TRIED MANEUVERING TOWARD AN OPEN AREA ON THE ARPT. HOWEVER, THE ACFT COLLIDED WITH TREES & CRASHED. AN EXAM OF THE ENG REVEALED THAT THE #3 EXHAUST VALVE PUSHROD WAS BENT & THE #1 INTAKE VALVE WAS BROKEN. AFTER THIS ACCIDENT, THE OWNER/OPERATOR (CAP) STOPPED USING PHILLIPS XC2 ENG OIL DUE TO POSSIBLE PROBLEMS ASSOCIATED WITH ITS USE WHICH INCLUDED STICKING VALVES.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land
- Flight time: 95 in this make and model; 129 in the last 90 days
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 3,464 hours
- Last inspection: annual inspection, November 15, 1985; 151 hours since
- Maximum gross weight: 2,150 lb
- Landing gear: fixed
- Engine: Lycoming O-360-A1A (piston); 0 hours total
- Operator: Civil Air Patrol-Maryland Wing
The flight
- Departed from: FME Ft Meade MD at 4:45 am
- Flight plan: VFR
- Runway 22, 8,000 ft by 200 ft
Weather at the time
- Light: night, dark
- Wind: from 250° at 5 knots
- Visibility: 12 statute miles
- Sky: scat at 10,000 ft
- Temperature: 72°F (22°C), dew point 66°F (19°C)
- Altimeter: 30.00 inHg
- Observation at 5:00 am from BAL, 29 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.