Sunday, June 19, 2016

Velocity SEFG, N7044Q: Accident occurred April 30, 2016 at Worcester Regional Airport (KORH), Worcester County, Massachusetts

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

Analysis 

The commercial pilot stated that, immediately after landing the experimental, amateur-built airplane, the nose landing gear (NLG) collapsed. Examination of the NLG revealed that the nosewheel and its mounting fork had separated. Further examination of the NLG fork revealed that it had fractured from overstress. The NLG fork was the original one installed in the airplane. Since that time, the manufacturer had determined that the original design was prone to shimmying, which could result in overstress fractures, and had twice modified the design to eliminate the failure. The new part design had not been installed on the airplane; therefore, the original NLG fork design, which was prone to fracture due to overstress, eventually fractured during the accident landing.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The overstress failure of the nose landing gear fork assembly.

Findings

Aircraft
Nose/tail landing gear - Failure (Cause)

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

Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Worcester, Massachusetts

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

Investigation Docket - National Transportation Safety Board: https://dms.ntsb.gov/pubdms

http://registry.faa.gov/N7044Q

NTSB Identification: ERA16LA177
14 CFR Part 91: General Aviation
Accident occurred Saturday, April 30, 2016 in Worcester, MA
Aircraft: MAHER DANIEL J VELOCITY, registration: N7044Q
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 April 30, 2016, about 1556 eastern daylight time, an experimental amateur-built Velocity SEFG, N7044Q, was substantially damaged during landing at Worcester Regional Airport (ORH), Worcester, Massachusetts. The airline transport pilot and passenger were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight conducted under the provisions of 14 Code of Federal Regulations Part 91.

According to the pilot, immediately after nose wheel contact upon landing, the nose wheel fork separated from the nose wheel landing gear strut, and the airplane began skidding on the bottom of the nose landing gear strut. After the separation of the nosewheel fork, the pilot applied held backpressure on the control stick, which resulted in a propeller strike.

The pilot stated that he had purchased the airplane in November 2015. There were no preflight anomalies noted before the local area flight, and no mechanical or performance deficiencies before the final full-stop landing. There was no record of any maintenance done on the nose landing gear fork.

Examination of photographs revealed the airplane rested on the nose landing gear strut with the nose wheel and its mounting fork separated. The nose wheel remained in the fork and the nose gear fork was fractured at the gear mount attach point. The propeller tips were damaged, and parallel slash marks consistent with a propeller strike were visible on the runway surface prior to where the airplane came to rest. The composite airframe structure at the nose landing gear strut attach point had also fractured, and had punctured the cockpit footwell, which resulted in substantial damage to the airframe. 

Further examination of the nose landing gear fork revealed it fractured from overstress. The manufacturer stated that this part and design had been modified twice because of similar fractures, as it had been discovered that excessive nose landing gear shimmying would result in overstress fractures. The first redesign included a dampener consisting of bellville washers to reduce stress on the nose fork. The next iteration included a hydraulic dampener. In addition to changing the design of the nose fork, the new parts were made of a different material. 

The accident airplane did not have either modification installed , and was the original nose fork installed on the airplane.

NTSB Identification: ERA16LA177
14 CFR Part 91: General Aviation
Accident occurred Saturday, April 30, 2016 in Worcester, MA
Aircraft: MAHER DANIEL J VELOCITY, registration: N7044Q
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 April 30, 2016, about 1556 eastern daylight time, a Velocity SEFG, N7044Q, was substantially damaged during landing at Worcester, Massachusetts. The airline transport rated pilot and passenger were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight conducted under the provisions of Title 14 Code of Federal Regulations Part 91, which originated at Worcester Regional Airport (ORH), Worcester, Massachusetts.

In a statement submitted to a Federal Aviation Administration (FAA), the pilot stated that upon landing, immediately after nose wheel contact, the nose strut collapsed and the airplane skidded on its nose. 

In a telephone interview with National Transportation Safety Board investigator-in-charge, the pilot stated that he had purchased the airplane in November, 2015. There were no preflight anomalies noted before the local area flight, and no mechanical or performance deficiencies before the final full-stop landing. There was no record of any maintenance done on the nose gear casting.

At 1554, the weather recorded at ORH included winds from 160 at 5 knots.

Examination of photographs revealed the airplane rested on the nose landing gear strut with the nose wheel and its mounting trunion separated. The nose wheel remained in the trunion, and the nose gear casting was fractured at the gear mount attach point. The propeller tips were damaged, and parallel slash marks consistent with a propeller strike were visible on the runway surface prior to where the airplane came to rest. The composite airframe structure at the nose landing gear strut attach point was fractured, and punctured the cockpit footwell, which resulted in substantial damage to the airframe. 

The nose gear casting segments were forwarded to the NTSB Materials Laboratory in Washington, DC for examination.

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