Ercoupe (Eng & Research Corp.) 415E accident near Kingman, Arizona, March 20, 1999
On March 20, 1999 at about 4:23 pm local time, a Ercoupe (Eng & Research Corp.) 415E, registered N94818, was destroyed in an accident near Kingman, Arizona (Kingman airport). It was a personal flight under general aviation rules (Part 91). 2 people were killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The in-flight loss of airplane control due to rear wing spar attachment fitting failure. The failure resulted from severe corrosion that was undetected during performance of an inspection specified by an airworthiness directive. The airworthiness directive developed by the FAA was deficient in its specificity relating to recurrence. The directive was also deficient in its procedure requiring external inspection, which would not reveal development of internal corrosion. Contributing factors to the accident were the turbulent atmospheric condition that exacerbated the wing loading and the pilot's operation of the airplane in excess of maximum authorized gross weight.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- March 20, 1999 · about 4:23 pm local time
- Place
- Kingman, Arizona · Kingman · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Ercoupe (Eng & Research Corp.) 415E
- Registration
- N94818 · no longer on the register · serial 4932
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
A ground-based witness, located north of the airport, reported observing the accident airplane's wings rolling right and left to nearly a vertical bank. Thereafter, the airplane entered a spin and impacted the ground while in a 30- to 45-degree nose low pitch attitude. The impact site was 0.6 miles from the approach end of the runway. Pilots ahead and behind the airplane reported experiencing moderate to extreme turbulence in the traffic pattern. The surface wind was reported at 14 knots with gusts to 22 knots. At the time of the accident the airplane was calculated to be between 94 and 127 pounds over its maximum certificated 1,400 pounds gross weight. During the on scene wreckage examination, the left wing's rear spar attachment fitting was found severely corroded, with missing rivet heads and was separated. Metallurgical examination of the severely corroded spar attachment fitting revealed the presence of rivet heads that had failed and popped off in flight and an associated corrosion-related crack that had compromised the structural integrity of the fitting assembly. Unable to sustain the imposed wing loading, the fitting failed in flight. The failed rivet heads and evidence of the corrosion was on the backside of the spar in an area not visible during inspections. In 1995, a one-time visual inspection of the wings' internal structure for corrosion was mandated by the Federal Aviation Administration through issuance of Airworthiness Directive 94-18-04. This 'one time' visual inspection requirement was complied with according to a logbook entry dated 1997, and thereafter the wings were recovered with fabric. In May 1998, the pilot purchased the airplane, which had been manufactured in 1948. In September 1998, the airplane received another annual inspection during which no logbook entry was made indicating that the wing's internal structure had been reexamined for evidence of corrosion. The corrosion developed due to the presence of moisture and the dissimilar metals (steel bracket riveted to an aluminum spar) being in contact with each other. The severity of the ongoing corrosion process between the metal components would not have been evident during an external visual inspection, despite the fact that a required access panel had not been installed pursuant to the AD. The AD inadequately addressed the aging aircraft issue by indicating compliance could be achieved through performance of a one-time visual inspection to ferret out nonviewable evidence of internal corrosion.
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: private
- Ratings: single-engine land
- Flight time: 254 hours in all; 23 in this make and model; 23 in the last 90 days; 12 in the last 30 days; 219 as pilot in command
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 1,887 hours
- Last inspection: annual inspection, September 29, 1998; 71 hours since
- Maximum gross weight: 1,400 lb
- Seats: 2
- Landing gear: fixed
- Engine: Continental C85-12F (piston); 0 hours total
The flight
- Departed from: HII Lake Havasu Cty AZ at 3:30 pm
- Destination: IGM
- Flight plan: none
- Runway 21, 6,831 ft by 150 ft
Weather at the time
- Light: daylight
- Wind: from 150° at 14 knots, gusting 22
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 66°F (19°C), dew point 36°F (2°C)
- Altimeter: 30.00 inHg
- Observation at 4:23 pm from IGM, 1 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.