Lake City, FL, USA
N9077C
CESSNA R182
The private pilot stated that, while on a cross-country flight, he noted that the airplane was losing electrical power and decided to make a precautionary landing. The pilot attempted to extend the landing gear and advised air traffic control of the emergency before all electrical power was lost. Since electrical power was lost before the landing gear extension cycle completed, he was unable to verify that the landing gear was down and locked in place, as the gear position indicator light would not illuminate due to the loss of electrical power. The pilot also referenced the manufacturer's emergency checklist for "Landing Without a Positive Indication of Gear Locking" and visually confirmed that the gear appeared to be fully extended. Upon touching down on the runway, the main landing gear collapsed, and the nose gear remained extended. Postaccident examination of the airplane revealed that the cause of the electrical power failure was the main electrical contactor, which had shorted out internally and burned. The part was original to the airplane and had accrued about 3,235 total hours. The landing gear was extended and retracted by hydraulic actuators operated by an electrically-driven hydraulic pump. It is likely that, when the pilot moved the landing gear selector to the down position, the extension cycle did not complete due to the loss of electrical power, resulting in insufficient hydraulic pressure to fully extend and lock the gear. The airplane was equipped with an emergency gear extension handle that would have allowed the pilot to manually complete the extension; however, the checklist that the pilot used did not instruct the pilot to manually lower and lock the gear. If the checklist had included the use of the emergency landing gear extension procedure, the pilot would likely have been able to manually increase hydraulic pressure in the system and avoid a gear collapse on landing.
On May 16, 2016, about 1106 eastern daylight time, a Cessna R182, N9077C, sustained substantial damage when the main landing gear collapsed during a precautionary landing at Lake City Gateway Airport (LCQ), Lake City, Florida. The private pilot was not injured. The airplane was registered to and operated by a private company. A visual flight rules flight plan was filed for the flight that originated from Punta Gorda Airport (PGD), Punta Gorda, Florida, about 0945, and was destined for DeKalb-Peachtree Airport (PDK), Chamblee, Georgia. Visual meteorological conditions prevailed for the personal flight conducted under 14 Code of Federal Regulations Part 91.The pilot stated that about one-hour into the flight, the entire instrument panel "began flickering then went completely dead." He checked all of the circuit breakers and reset the avionics master switch, but was unable to restore electrical power. Before losing all power, the pilot informed air traffic control of the electrical failure and that he would be making a precautionary landing at LCQ. He then reduced speed and extended the landing gear via the landing gear extension handle. The pilot said that when he visually checked the left main gear (pilot side) it appeared to be down and locked, but he was unable to verify because the gear down-and-locked light was not working due to the loss of electrical power. When the pilot arrived at LCQ, the control tower used light gun signals to instruct him to fly by the tower, after which, they cleared him to land with a solid green light signal. When the airplane touched down, the main landing gear collapsed and the nose gear remained extended. This resulted in substantial damage to the right horizontal stabilizer. Several antennas and the rightwing tip were also damaged. According to the Cessna R182 Pilot Operating Handbook (POH), page 7-11 to 7-12, Landing Gear System, "The landing gear extension, retraction, and main gear down and lock operation is accomplished by hydraulic actuators powered by an electrically-driven hydraulic power pack. Power pack operation is started and stopped by a pressure switch and hydraulic pressure is directed by the landing gear lever." Once the lever is moved to the up or down position, it directs hydraulic pressure to move the gear to the selected position. Two position indicator lights are provided to show the landing gear position; a green light indicates the gear is down and locked and an amber light means the gear is up or retracted. The POH also said, "During a normal cycle, the gear retracts or extends and locks, limit switches close, and the indicator lights comes on indicating completion of the cycle. After indicator light illumination, the power pack will continue to run until the fluid pressure reaches 1500 PSI, opens the pressure switch, and turns the power pack off. A normal operating pressure of 1000 PSI to 1500 PSI is automatically maintained in the landing gear system, and is sufficient to provide a positive up pressure on the main landing gear. The nose gear incorporates an over-center mechanical linkage which provides a positive mechanical up and down lock." If electrical power was interrupted at any point prior to or during the extension cycle, the hydraulic power pack would have been unable to maintain sufficient pressure in the system to fully extend the landing gear. A review of the airplane's POH Emergency Procedures, page 3-9, LANDING WITHOUT POSITIVE INDICATION OF GEAR LOCKING stated: 1. Before Landing Check - - COMPLETE. 2. Approach -- NORMAL (full flap). 3. Landing Gear and Gear Pump Circuit Breakers --IN. 4. Landing -- TAIL LOW as smoothly as possible. 5. Braking -- MINIMUM necessary 6. Taxi -- SLOWLY. 7. Engine -- SHUTDOWN before inspecting gear The pilot stated that he followed this checklist prior to landing, in addition to visually checking the landing gear himself. Though the airplane was equipped with an emergency landing gear extension handle, though this checklist did not call out for its use. The POH only instructed the pilot to use the emergency landing gear extension handle when the landing gear failed to extend. A review of the emergency checklist procedures for Electrical Power Supply System Malfunctions also did not mention for the pilot to use the emergency hand pump to extend the landing gear in the event of a complete electrical failure. A postaccident examination of the airplane by a mechanic revealed the main electrical contactor was installed correctly, but was burned and had shorted out internally. The part was original to the airplane and had accrued about 3,235 total hours of operation. The pilot held a private pilot certificate with a rating for airplane single-engine land. He reported a total of 369 hours of flight experience, of which 272 hours were in a Cessna R182. Weather reported at the airport around the time of the accident was clear skies, visibility 10 miles, and light winds.
Internal failure of the main electrical contactor, which resulted in a complete loss of electrical power and an inability to extend the landing gear through normal means.
Source: NTSB Aviation Accident Database
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