Waco YMF5 accident near Lake Buena Vist, Florida, July 28, 1997
On July 28, 1997 at about 8:40 pm local time, a Waco YMF5, registered N14128, was substantially damaged in an accident near Lake Buena Vist, Florida. It was a flight of an unrecorded kind under general aviation rules (Part 91). No one was hurt; 3 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
failure of maintenance personnel to follow installation procedures pertaining to the torque of the propeller retention nut, which resulted in a loose propeller retention nut, subsequent fatigue failure of the crankshaft, and loss of engine power. The lack of suitable terrain for an emergency landing was a related factor.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 28, 1997 · about 8:40 pm local time
- Place
- Lake Buena Vist, Florida · map
- Type
- Accident
- Injuries
- No one was hurt; 3 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Waco YMF5
- Registration
- N14128 · registry record · serial 4213
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
During cruise flight, the pilot noted an engine vibration followed by a total loss of engine power. He made a forced landing, but was unable to reach suitable terrain. During the landing rollout, he observed a ditch and intentionally ground looped the airplane, but the airplane collided with a pole. Examination of the propeller revealed the propeller retention nut was hand tight. Galling was present on the propeller hub mounting flange and the rear cone. Disassembly of the engine assembly revealed the crankshaft was broken at the counterweight flange. Visual inspection of the shear surfaces on the crankcase showed tell tale benchmarks that appeared to have originated at the oil way plug threads and progressed through approximately one fifth of the crank circumference. Interviews with personnel involved with the installation revealed they had retorqued the propeller, but had not followed accepted industry practices in establishing proper hub to rear cone contact surfaces.
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: airline transport pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: glider; instructor: helicopter; instructor: instrument airplane; instructor: instrument helicopter; instrument: airplane; instrument: helicopter; rotorcraft: glider; rotorcraft: helicopter
- Flight time: 6,636 hours in all; 179 in this make and model; 225 in the last 90 days; 72 in the last 30 days; 5,973 as pilot in command; 1,872 on instruments
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 4,045 hours
- Last inspection: continuous airworthiness programme, July 6, 1997; 33 hours since
- Maximum gross weight: 2,500 lb
- Seats: 3
- Landing gear: fixed
- Engine: Jacobs R-755-9 (piston); 0 hours total
- Operator: Reilly Aviation
The flight
- Departed from: ISM Kissimmee FL at 8:10 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 200° at 5 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 5,000 ft; not recorded
- Temperature: 91°F (33°C), dew point 72°F (22°C)
- Altimeter: 30.00 inHg
- Observation at 7:55 pm from MCO, 20 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 2 |
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.
Other NTSB records under N14128 the same tail number, which may have belonged to a different aircraft at the time
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.