Enstrom F-28C accident near Waverly, Iowa, July 20, 2003
On July 20, 2003 at about 1:30 pm local time, a Enstrom F-28C (helicopter), registered N51699, was substantially damaged in an accident near Waverly, Iowa. It was an aerial observation flight 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
The main rotor blade push-pull rods being corroded, sustaining fatigue, and separating in cruise and the main rotor blade contacting the tail boom during the emergency landing. Factors were the diminished aircraft control and the vibrations encountered during flight after the rod separation.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 20, 2003 · about 1:30 pm local time
- Place
- Waverly, Iowa · map
- Type
- Accident
- Injuries
- No one was hurt; 3 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Enstrom F-28C · all F-28Cs on the register
- Registration
- N51699 · registry record · serial 416
- Damage
- Substantial damage
- Flight
- Aerial observation flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The helicopter sustained substantial damage when the main rotor blade impacted the tail boom during a forced landing. The helicopter experienced in-flight vibrations prior to the forced landing. The pilot stated that the helicopter experienced extreme vibration in-flight at 200 feet above ground level. He said that helicopter control was "10% to nil." An examination revealed that one of three Push-Pull Rod Assemblies, part number 28-16253-1, was found corroded and separated. The operator's fleet of aircraft was examined and four other control rods were found with corrosion. Examination of the rod with the separation from the accident helicopter at the National Transportation Safety Board's Materials Laboratory revealed that "most of the fracture areas were on a plane that was nearly perpendicular to the longitudinal axis of the rod, indicative of a brittle fracture mechanism such as fatigue cracking." The pilot stated, "Pitch control rod has no inspection procedure at this time. It rusted from inside and not visible from outside." Subsequent to the accident, Enstrom issued Service Directive Bulletin (SDB) No. 0096. The bulletin directs visual inspection of control rods with part number 28-16253-1 and 28-16253-101 according to their time in service on F-28A, F-28C, F-28F, 280, 280C, 280F, and 280FX helicopters.
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: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: helicopter; instructor: instrument airplane; instrument: airplane; rotorcraft: helicopter
- Flight time: 45,000 hours in all; 8,000 in this make and model; 200 in the last 90 days; 45,000 as pilot in command
- Last flight review: March 2, 2003
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 3,100 hours
- Last inspection: annual inspection, July 6, 2003; 20 hours since
- Maximum gross weight: 2,200 lb
- Seats: 3
- Landing gear: fixed
- Engine: Lycoming HIO360E1AD (piston); 0 hours total
The flight
- Departed from: C25 Waverly IA at 1:17 pm
- Destination: C25
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 290° at 7 knots
- Visibility: 5 statute miles
- Sky: a few clouds at 900 ft
- Temperature: 75°F (24°C), dew point 70°F (21°C)
- Altimeter: 29.93 inHg
- Observation at 12:54 pm from ALO, 12 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 N51699 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.