Loral Corp. GZ-22 accident near Mogadore, Ohio, October 28, 1999
On October 28, 1999 at about 10:41 pm local time, a Loral Corp. GZ-22 (airship), registered N4A, was substantially damaged in an accident near Mogadore, Ohio (Wingfoot Lake Balloonport airport). It was an other work-use flight under general aviation rules (Part 91). 1 person had minor injuries; 1 other was unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The failure of the flight control system manufacturer to meet design (hardness) specifications that resulted in stripped splines.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 28, 1999 · about 10:41 pm local time
- Place
- Mogadore, Ohio · Wingfoot Lake Balloonport · map
- Type
- Accident
- Injuries
- 1 person had minor injuries; 1 other was unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Loral Corp. GZ-22
- Registration
- N4A · registry record · serial 4120
- Damage
- Substantial damage
- Flight
- Other work-use flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot of the fly-by-wire airship flew several traffic patterns and approaches from both the pilot and co-pilot stations. After he departed the traffic pattern and leveled the airship, it entered an uncommanded, descending left-hand turn. The control panel displayed no indication of a malfunction, and emergency and troubleshooting procedures failed to regain control of the airship. The airship landed in trees, and both the pilot and the technician on board escaped injury. Metallurgical examination of the actuators that convert electrical signals to mechanical flight control inputs revealed that the splined shafts on the output side of the starboard actuator were almost completely stripped, and provided no flight control input. The gear teeth of the splined shafts on the output side of the port actuator were worn to 25 percent of their original thickness, and did not provide full flight control input. Hardness testing revealed the output shafts of both the port and starboard actuators did not meet the manufacturer's specified hardness requirement. The manager of the airship fleet said the one-of-a-kind airship would not be rebuilt.
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; instructor: airplane single-engine; instrument: airplane; rotorcraft: airship
- Flight time: 1,468 hours in all; 374 in this make and model; 190 in the last 90 days; 60 in the last 30 days; 918 as pilot in command; 451 on instruments
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 12,632 hours
- Last inspection: annual inspection, October 19, 1999; 43 hours since
- Maximum gross weight: 16,500 lb
- Seats: 10
- Landing gear: fixed
- Engine: Allison 250-B17C (turboshaft); 0 hours total
The flight
- Departed from: 4OH6 at 9:25 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 190° at 8 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 25,000 ft; not recorded
- Temperature: 63°F (17°C), dew point 37°F (3°C)
- Altimeter: 30.00 inHg
- Observation at 9:51 pm from CAK, 4 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | 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.