Friday, July 28, 2017

Bob Howell, Howell Special, N4393H: Accident occurred May 27, 2016 at Minden-Tahoe Airport (MEV), Douglas County, Nevada

Aviation Accident Final Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

NTSB Identification: WPR16LA117
14 CFR Part 91: General Aviation
Accident occurred Friday, May 27, 2016 in Minden, NV
Probable Cause Approval Date: 09/06/2017
Aircraft: HOWELL BOB HOWELL SPECIAL, registration: N4393H
Injuries: 2 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

The private pilot reported that the landing was “normal” but that, during the landing roll, he noticed that the experimental, amateur-built airplane started veering to the left. Shortly thereafter, the right wing suddenly dropped and impacted the runway. He was unable to maintain directional control of the airplane, and it veered off the runway because the right main landing gear (MLG) had collapsed. 

Postaccident examination of the right MLG assembly revealed that the right main tire and wheel had separated from the airplane and that a strut had separated about midpoint. Examination of the fracture features of the right MLG assembly revealed that they exhibited matte-gray features on slant angles, consistent with a ductile overstress fracture. No evidence of preexisting cracks or significant corrosion was observed. The right MLG assembly likely failed due to a hard landing and/or side loading on the MLG. 

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:
The failure of the right main landing gear assembly due to overstress fracture. 

The National Transportation Safety Board did not travel to the scene of this accident.

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Reno, Nevada

Aviation Accident Factual Report - National Transportation Safety Board: https://app.ntsb.gov/pdf

http://registry.faa.gov/N4393H

NTSB Identification: WPR16LA117
14 CFR Part 91: General Aviation
Accident occurred Friday, May 27, 2016 in Minden, NV
Aircraft: HOWELL BOB HOWELL SPECIAL, registration: N4393H
Injuries: 2 Uninjured.

NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

On May 27, 2016, about 1050 Pacific daylight time, an amateur built - experimental Bob Howell, Howell Special airplane, N4393H, sustained substantial damage during the landing roll at the Minden-Tahoe Airport (MEV), Minden, Nevada, following a landing gear collapse. The private pilot and sole passenger on the airplane were not injured. The airplane was registered and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight which originated from Bryant Field Airport, Bridgeport, California, about 1015.

The pilot reported a normal landing, however, during the landing roll he noticed the airplane started to veer to the left. He counteracted the veering with right rudder, and brake. Shortly thereafter, about 400 ft down the runway, the right wing suddenly dropped and impacted the runway. He was unable to maintain direction control of the airplane as it veered off the runway. There were no witnesses to the accident.

Examination of the airplane by a Federal Aviation Administration inspector revealed that the right wing was substantially damaged. The wreckage was transported to a secure location for further examination.

Postaccident examination of the right landing gear assembly revealed that the right main wheel and tire assembly had separated from the airplane. Further, the remaining main gear, a-frame structure, had a strut that had separated about at the midpoint. The bolts and their respective attachment structures that attached the gear assembly to the airframe were intact. All fracture surfaces of the main gear assembly were sent to the NTSB Materials Laboratory for further examination.

The laboratory determined that the fracture features in the tubular steel structure portions showed matte gray features on slant angles consistent with a ductile overstress fracture. Some areas were observed that were consistent with sliding contact between the fracture surfaces under bending or shear loads. The end fitting was fractured in the threads and also had matte gray fracture features and the adjacent deformation of the threads was consistent with a ductile overstress fracture. No evidence of preexisting cracks or significant corrosion was observed.

The owner/builder stated that several years earlier he made a repair to the landing gear where he heated the welds to realign the gear. However, a ductile overstress fracture would be consistent with a hard landing and/or side loading on the main gear.

NTSB Identification: WPR16LA117
14 CFR Part 91: General Aviation
Accident occurred Friday, May 27, 2016 in Minden, NV
Aircraft: HOWELL BOB HOWELL SPECIAL, registration: N4393H
Injuries: 2 Uninjured.

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

On May 27, 2016, about 1050 Pacific daylight time, an experimental, amateur built, Howell Special, N4393H, sustained substantial damage during the landing roll at the Minden-Tahoe Airport (MEV), Minden, Nevada, following a landing gear collapse. The airplane was registered and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. The private pilot and sole passenger on the airplane were uninjured. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight which originated from Bryant Field Airport, Bridgeport, California, at about 1015. 

The pilot reported a normal landing, however, during the landing roll he noticed the airplane settled to the right and he was unable to maintain direction control of the airplane as it veered off the runway, to the left.

Examination of the airplane by a Federal Aviation Administration inspector revealed that the right wing was substantially damaged. The wreckage was transported to a secure location for further examination.

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