Grumman G-164B accident near Port O'Connor, Texas, May 20, 1986
On May 20, 1986 at about 9:00 pm local time, a Grumman G-164B, registered N6740Q, was substantially damaged in an accident near Port O'Connor, Texas. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). No one was hurt; 1 person was 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
- May 20, 1986 · about 9:00 pm local time
- Place
- Port O'Connor, Texas · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Grumman G-164B · all G-164Bs on the register
- Registration
- N6740Q · no longer on the register · serial 254-B
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
ACFT FLIPPED OVER ON TOUCHDOWN DURING AN EMERGENCY LANDING IN A CULTIVATED FIELD FOLLOWING A PARTIAL POWER LOSS DURING A SWATH RUN AT 30 FT AGL. INVESTIGATION REVEALED THAT THE NO. 1 CYL EXHAUST VALVE PUSH ROD HAD FAILED. EXACT CAUSE OF THE PUSH ROD FAILURE WAS NOT DETERMINED.
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; rotorcraft: helicopter
- Flight time: 10,900 hours in all
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: ctr
The aircraft
- Airframe total time: 3,533 hours
- Last inspection: inspection type not recorded, April 20, 1986; 90 hours since
- Maximum gross weight: 4,500 lb
- Seats: 1
- Landing gear: fixed
- Engine: P&W R-1340-4N1 (piston); 0 hours total
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 030° at 5 knots
- Visibility: 15 statute miles
- Sky: not recorded; not recorded
- Temperature: 82°F (28°C), dew point 55°F (13°C)
- Altimeter: 29.00 inHg
- Observation at 9:49 pm from IAH, 130 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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.
Other NTSB records under N6740Q 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.