Primary finding
Probable cause
The pilot's failure to recognize that both engines were being supplied fuel only from the right main fuel tank, resulting in fuel starvation and a subsequent loss of engine power from both engines. Contributing to the incident were the pilot's inability to properly position the left fuel selector valve and the airplane operator's misinterpretation of the manufacturer's service recommendations to lubricate the fuel selector detents.
Investigator assessment
Analysis narrative
In the three months prior to the incident there were no reported discrepancies by any flight crew member related to either fuel selector valve. The incident flight was the pilot's fourth flight of the day in the incident airplane. The first three flights were uneventful; however, the pilot noticed that the difference between the left and the right fuel quantities became increasingly larger during the second, third, and fourth flights when the left fuel quantity indicator was indicating a greater amount than the right. During the third flight, the pilot attempted to correct the fuel imbalance by supplying fuel to both engines from the left main fuel tank for a brief period, then returned the right fuel selector to the right tank position. Before takeoff of the incident flight, the pilot noted a 100-pound fuel imbalance; the left fuel quantity was indicating 300 pounds and the right fuel quantity was indicating 200 pounds. While climbing to 6,000 feet, he noticed a slight right-wing-heavy tendency but did not correct it at that time. The flight continued toward the destination airport and the fuel imbalance became greater as the flight progressed. Approximately halfway into the flight, for approximately 15 minutes, the pilot repositioned the left fuel selector to the right tank position; at that time the left fuel quantity gauge indicated 300 pounds and the right fuel quantity gauge indicated between 90 and 100 pounds. After 15 minutes he repositioned the left fuel selector to its respective tank position but was not able to position it into the detent and he failed to detect that the left fuel selector was not in the detent. The flight continued toward the destination airport with both engines being supplied fuel from the right main fuel tank. As the flight approached an area called Marco Island, the pilot became concerned because the left fuel quantity gauge was indicating 300 pounds and the right fuel quantity gauge indicated 50 pounds. He later stated that he thought the imbalance to be an indication issue. The flight continued toward the destination airport and the right engine began surging; the right fuel quantity indicator was indicating zero at that time while the left fuel quantity indicator was indicating approximately 300 pounds. He immediately moved the right fuel selector to the left tank position (crossfeed), which restored engine power; then the left engine began to surge, followed by the right engine. Unable to restore engine power in both engines, the pilot declared an emergency with air traffic control and executed a 180-degree turn towards Naples Municipal Airport. While descending he successfully feathered both propellers and landed uneventfully on runway 14 at the Naples Municipal Airport. Following recovery of the airplane only residual fuel was noted in the fuel lines and both engine compartments, which is consistent with total fuel starvation. An adequate quantity of fuel was noted in the left main fuel tank. Postincident testing revealed the left main fuel selector would not travel into the main tank detent upon selection in the cockpit because of inadequate lubrication of the fuel selector detents. Lubrication of the fuel selector detents was not being performed by the operator due to their misinterpretation of the airplane manufacturer maintenance manual. Additionally, the operator was using an incorrect lubricant on the fuel selector gearbox. Misinterpretation of the maintenance manual also occurred with six other operators who operate the Cessna 402C airplanes. Both engines operated normally after an adequate quantity of fuel was supplied to them.
Source record
Factual narrative
HISTORY OF FLIGHT On January 22, 2009, about 1910 eastern standard time, a Cessna 402C, N2615G, registered to Hyannis Air Service, Inc., operated by Cape Air as Continental Connection Flight 9399, experienced a total loss of engine power from both engines and was not damaged during a forced landing at Naples Municipal Airport (APF), Naples, Florida. Visual meteorological conditions prevailed at the time and an instrument flight rules (IFR) flight plan was filed for the 14 Code of Federal Regulations (CFR) Part 135 scheduled, domestic passenger flight from Key West International Airport (EYW), Key West, Florida, to Southwest Florida International Airport (RSW), Fort Myers, Florida. The airline transport-certificated pilot and six passengers were not injured. The flight originated about 1828, from EYW. The incident flight was the pilot’s fourth leg that day in the incident airplane. Prior to the first flight that day from RSW to EYW operating as flight 9396, a total of 90 pounds of fuel were added to each main fuel tank. The fuel quantity gauges indicated 500 pounds total after fueling. The 55 minute flight (block time) to EYW was uneventful and was flown at 7,000 feet. He operated the airplane with each fuel selector positioned to its respective tank and did not crossfeed during this flight. After landing at EYW 90 pounds of fuel were added into each main tank. He did not recall the left or right fuel gauge reading after the fueling. He stated he did not recall a difference between the left and right fuel quantity indications. The second flight that day from EYW to RSW, operating as flight 9397, was uneventful and flown at 6,000 feet. The flight lasted approximately 55 minutes (block time). He operated the airplane with each fuel selector positioned to its respective tank and did not crossfeed during this flight. After landing at RSW, 180 pounds of fuel were added into each main tank. He watched the fueling and also checked the fuel slip. After fueling, the fuel quantity gauges indicated a total of 650 pounds; the left fuel quantity gauge indicated 350 pounds and the right fuel quantity gauge indicated 300 pounds. The third flight that day from RSW to EYW, was operated as flight 9398. Before departure he noted the 50 pound fuel imbalance. The flight departed with each fuel selector positioned to its respective fuel tank, and climbed to 7,000 feet. Upon reaching cruise, he set cruise power, then moved the right fuel selector to the left main fuel tank position (crossfeed). He stated that he believed he flew in this condition for 15 to 20 minutes in order to balance the fuel load. At the end of the estimated time he repositioned the right fuel selector to its respective tank then began to descend. He did not recall the left or right fuel quantity gauge readings at the end of the crossfeeding. The block time was 55 minutes or maybe 1 hour. No fuel was added at EYW. The fourth flight that day from EYW to RSW (incident flight), was operated as flight 9399. The pilot did not visually inspect the fuel tanks before departure. Before takeoff, he noted the left fuel quantity gauge indicated 300 pounds and the right fuel quantity gauge indicated 200 pounds. He did a quick engine run-up before takeoff to check the operation of the magnetos with no discrepancies reported. He does not recall the seating positions but noted a male was in the co-pilot’s seat. He did brief the passengers; a total of 6 passengers were on-board. The flight departed with each fuel selector positioned to its respective tank, and while climbing to 6,000 feet, he noted the airplane appeared to be right wing heavy (slightly). He noted this but did not perform any action. He set cruise power and noted during cruise flight the left fuel quantity gauge indicated 280 pounds and the right fuel quantity gauge indicated 160 pounds. Approximately ½ way into the flight during cruise flight, he repositioned the left fuel selector valve to the right main tank position (crossfeed) and left it there for approximately 15 minutes. At that time the left fuel quantity gauge indicated 300 pounds and the right indicated between 100 and 90 pounds. He repositioned the left fuel selector to its respective tank position; at that time the flight was 60 to 55 nautical miles from RSW. Air traffic control communications were transferred from Miami Air Route Traffic Control Center (Miami ARTCC), to Fort Myers Approach Control. He obtained the automated terminal information service (ATIS) from RSW, and when the flight was approaching Marco Island, the left fuel quantity gauge was indicating 300 pounds and the right fuel quantity gauge indicated 50 pounds. He stated he was “starting to get concerned.” When approaching Naples, Fort Myers Approach Control instructed him to descend to 4,000 feet. He was “still seeing 300 pounds on the left and below 50 pounds on the right.” He never operates the airplane below 100 pounds in either tank, and later stated he thought the fuel load difference was an indication issue. He later stated, “I was working on that problem” and when asked he stated he meant in his head. All engine instruments were normal. The flight continued towards the destination airport and when past Naples flying at 4,000 feet over land, he was just about to call operations reporting in-bound and the right engine began surging first. He looked at the right fuel gauge and it indicated 0. The left fuel quantity gauge at that time indicated 300 pounds or “maybe north of that.” He immediately moved the right fuel selector to the left tank position (crossfeed), which restored engine power. He did not consider this an emergency at that time. The left engine then began surging, followed by the right engine. He repositioned the right fuel selector to its respective tank, adjusted power, and visually checked the positions of the fuel selectors, mixture controls, engine instruments, and magnetos. With respect to the magneto switches, he only visually verified they were on. Unable to maintain altitude due to the loss of power from both engines, he declared an emergency with Fort Myers Approach Control and advised he needed to fly to APF. He was cleared to APF, did a 180 turn towards there, and while flying at 3,000 feet, he feathered the propellers and began looking for the APF airport. He saw the runway end identifier lights (REILS), and Fort Myers Approach asked him if he could see the APF airport. He stated he did, and aimed for the middle of the airport. The runway lights for runway 14 came into view and he lined up for runway 14. He held the gear until he was sure he could land on the runway then blew down the gear with the emergency blow down bottle. He landed with full flaps, and rolled to the end of the runway then onto a taxiway and stopped the airplane. He turned around to the passengers and the fire department (FD) showed up. He talked with FD personnel but doesn’t recall too much more. He did not recall moving the fuel selectors and stated he didn’t think he did. He also recalled that the right fuel quantity gauge precipitously went from 50 pounds to 0. Five of the six passengers reported in writing that the left engine quit first followed by the right engine. One male passenger reported in writing that upon takeoff from EYW, the left fuel quantity gauge indicated “[300] lb and the right around [100] lb. On landing at Naples the left hand gauge showed [350] lb but the right showed empty.” All of the passengers reported the pilot told them to brace for impact and to make sure their seatbelts were tight. The airplane was towed by Naples Airport Authority personnel to the ramp, and was put into a hangar later that evening and secured. Naples Airport Authority did not put any fuel into the airplane after it landed. PERSONNEL INFORMATION The pilot, age 63, holds an airline transport pilot certificate with rating(s) airplane single and multi-engine l