Wednesday, April 12, 2017

Beech A36TC Bonanza, Level '5', N755R: Incident occurred April 10, 2017 in Livermore, Alameda County, California

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

Additional Participating Entities: 
Federal Aviation Administration / Flight Standards District Office; Oakland, California
Honeywell; Olathe, Kansas

Aviation Incident Preliminary Report -  National Transportation Safety Board: 

LEVEL '5':

NTSB Identification: WPR17IA086
14 CFR Part 91: General Aviation
Incident occurred Monday, April 10, 2017 in Livermore, CA
Aircraft: BEECH A36TC, registration: N755R
Injuries: 1 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 used data provided by various sources and may not have traveled in support of this investigation to prepare this aircraft incident report.

On April 10, 2017, about 1030 Pacific daylight time, a Beech A36TC, N755R, landed gear-up at Livermore Municipal Airport, Livermore, California after the pilot experienced a flight control malfunction during the landing approach. The airplane was registered to Level '5' (Corporation) and operated by the pilot under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The commercial pilot was not injured, and the airplane sustained minor damage. The local personal flight departed Tracy Municipal Airport, Tracy, California, about 1015. Visual meteorological conditions prevailed and no flight plan had been filed.

The pilot stated that he departed earlier in the morning from Livermore with the intention of performing a "warm-up" flight. The preflight checks were uneventful, and after departing, he flew northeast for about 30 miles. He then turned southwest towards Tracy with the aid of the autopilot. As he approached Tracy, he disengaged the autopilot, and performed four uneventful landings and takeoffs. He then departed west towards Livermore, again using the autopilot after he had trimmed the airplane for level flight.

He contacted the Livermore Air Traffic Control Tower, and was given a straight-in clearance for runway 25L. Shortly after contacting the tower, he disengaged the autopilot using the autopilot disconnect button on the control yoke. The airplane immediately pitched aggressively up about 50 degrees with an immediate loss of airspeed. The pilot stated that the pitch up happened so fast that he feared the airplane was about to stall. He applied full forward pressure on the control yoke, and the airplane pitched almost directly nose down, and began to quickly build airspeed. He then reduced the yoke forward pressure, and the airplane pitched back up again. The pilot reduced engine power, set the landing gear selector switch to down, and extended the flaps. He stated that he heard the landing gear extend, and confirmed that the three green landing gear lights had illuminated. With full forward yoke pressure, he was able to maintain an approximate level attitude, although the control forces were so great that he needed to use both hands and his knee to keep the yoke forward.

He then called the tower, declared an emergency, and was given an amended clearance to land on runway 25R. He attempted to reach over to the autopilot circuit breaker, but it was out of his reach, and because of his hold on the yoke, he feared he would immediately lose control of the airplane if he released his grip. He previously experienced an engine throttle cable failure, and suspected that this time the elevator control system had either stuck or failed.

The pilot reached down to adjust the elevator trim wheel, but it would not move, and he could not safely move himself into a position to look down and observe the elevator tab position indicator. He continued the approach, and regulated pitch by adjusting engine power, and holding the yoke fully forward. The airplane continued to porpoise as he initiated a gradual descent back to the airport. He stated that at some point during the approach and ensuing struggle, he inadvertently knocked off his glasses and headset, so was no longer able to hear the tower controller. Although the tower controller made multiple calls during the final approach warning the pilot that the landing gear was not extended, but the pilot did not hear those calls due to his loss of the headset. The airplane touched down on runway 25R, and it was then that the pilot realized the landing gear was not extended. The airplane came to a stop on its belly and the pilot immediately egressed.

An airport operations staff member immediately responded to the airplane, and turned off the master switch, magnetos, and fuel selector valve. He noted that the landing gear selector switch was in the down position, and the landing gear and auxiliary fuel pump circuit breakers were both tripped.

Postaccident examination revealed that the elevator tab gauge indicated "18U" (up), and the elevator tabs were in the tab down (airplane nose-up) position.

The airplane was equipped with dual controls. Examination revealed that with the yoke in the full-forward position, the yoke T-bar obscured the view of the lower center portion of the instrument panel, blocking the view of the elevator tab indicator, and obscuring left seat occupant access to most of the circuit breakers, including the autopilot and trim breakers. Additionally, while holding the yoke fully forward with an extended left arm, it was not possible to reach the autopilot and trim circuit breakers.

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