# NTSB LAX92LA235: Mcquen Glassair III, N115DM, Casa Grande, AZ, May 10, 1992

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: May 10, 1992, 07:30 local (14:30 UTC)
- Place: Casa Grande, AZ
- Location: 32.8795° N, 111.7574° W: Placed by OpenAirDocs: center of Casa Grande, AZ, within about 6 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=32.8795&lon=-111.7574&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report June 30, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27640
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX92LA235
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27640/pdf
- Page: https://openairdocs.org/ntsb/LAX92LA235

## Probable cause

FUEL STARVATION DUE TO THE PILOT'S MISREADING OF A NEWLY INSTALLED FUEL SELECTOR PANEL WITH PLACARDS AND A POSITION POINTER WHICH WERE CONFUSING. FACTORS IN THE ACCIDENT WERE THE CONFUSING NATURE OF THE FUEL PANEL AND PLACARD DESIGN AND THE SCHOOL BUS WHICH SUDDENLY TURNED IN FRONT OF THE LANDING AIRCRAFT.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Loss of engine power(total) - nonmechanical, cruise
  - fluid,fuel - starvation (cause)
  - fuel tank selector position - improper, pilot in command (cause)
  - acft/equip,inadequate control shape/size, manufacturer (contributing factor)
- Forced landing, descent - emergency
  - terrain condition - roadway/highway
- In flight collision with object, landing
  - object - vehicle (contributing factor)
  - proper touchdown point - not possible, pilot in command (contributing factor)
  - object - tree(s)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

ACCORDING TO THE PILOT, THE AIRCRAFT HAD JUST COME OUT OF A MAINTENANCE PERIOD WHERE PLACARDS WERE INSTALLED ON THE FUEL SELECTOR PANEL. THE FUEL SELECTOR HAS A HANDLE AND A POINTER, WHICH, ACCORDING TO THE PILOT, ARE SIMILAR IN SHAPE AND SIZE. THE PILOT SAID THAT HE HAD NEVER MOVED THE FUEL SELECTOR VALVE FROM THE MAIN TANK POSITION SINCE HE PURCHASED THE AIRCRAFT. THE VALVE WAS APPARENTLY FOUND IN THE 'HEADER TANK' POSITION AFTER THE ACCIDENT. THE HEADER TANK ONLY HOLDS 4 GALLONS OF FUEL AND IS FOR EMERGENCY USE ONLY. THE PILOT THOUGHT THE FUEL SELECTOR WAS POSITIONED TO THE MAIN TANK. THE AIRCRAFT HAD BEEN AIRBORNE FOR 15 MINUTES WHEN THE ENGINE SUDDENLY QUIT. THE PILOT LINED UP FOR A LANDING ON A ROAD, HOWEVER, WHEN THE AIRCRAFT WAS ON SHORT FINAL A SCHOOL BUS TURNED ONTO THE ROAD DIRECTLY IN FRONT OF THE AIRCRAFT. THE PILOT TURNED LEFT TO AVOID COLLIDING WITH THE BUS AND HIT A LARGE TREE.

## Aircraft

- Registration: [N115DM](https://openairdocs.org/deregistered/N115DM-2007-06-04), registration cancelled 2007-06-04, S/N 3029, built 1989 (OpenAirDocs)
- Reported make and model: MCQUEN GLASSAIR III (GLASSAIR I)
- Registry model: [Mcewen Dick GLASAIR III](https://openairdocs.org/model/mcewen-dick-glasair-iii) (registry code 056559M) (OpenAirDocs)
- Registry engine: [Lycoming IO-540 series](https://openairdocs.org/engine/lycoming-io-540-series) (registry code 41530, reciprocating) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 3029
- Airframe hours: 122
- Engines: LYCOMING IO-540-R 300 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Charles J. Rothweiler
- Registered owner: Charles J. Rothweiler
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, April 1, 1992, 6 hours before
- Departed: CHD, CHANDLER, AZ

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 56; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 1,250 total, 12 in this make and model, 1,250 as pilot in command, 52 in the last 90 days, 32 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 70 °F, dew point 50 °F
- Altimeter: 29.00 inHg

## Other investigations on N115DM (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB LAX92LA176](https://openairdocs.org/ntsb/LAX92LA176), Apr 10, 1992: Mcewen Dick Glasair III (N115DM), Casa Grande, AZ, substantial damage. Probable cause: A FAILURE OF THE PILOT TO SELECT THE PROPER FUEL TANK AND SUBSEQUENT FUEL STARVATION. CONTRIBUTING TO THE ACCIDENT WAS AN INADEQUATE DESIGN BY THE MANUFACTURER THAT PERMITTED THE FUEL SELECTOR TO BE…

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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