Accident Overview
On 17 July 2021, a Cessna 402C (registration VQ-TIN) operated a commercial air transport flight from Providenciales International Airport to Harold Charles International Airport on Ambergris Cay, Turks and Caicos Islands. The pilot, who held an Airline Transport Pilot Licence and had 10,500 total flying hours (400 on type), was the sole crew member with five passengers on board. The aircraft landed on Runway 07 at approximately 1923 UTC without the landing gear extended, resulting in extensive damage to the flaps, propellers, and underside of the fuselage. Both engines were shock-loaded. No injuries occurred.
Flight History
The flight was the pilot’s seventh of the day. After initial difficulty starting the assigned aircraft's engines, the pilot elected to switch to another Cessna 402C that had already completed two sectors that day with a different pilot. The pilot conducted a visual external check of the replacement aircraft but did not perform a thorough internal pre-flight check, which included testing the landing gear warning horn. One passenger sat in the co-pilot's seat at the pilot's offer. The departure and cruise were uneventful. Weather at Ambergris Cay was good with wind from 070° at 13 kt.
At approximately 3 nm from landing, the pilot selected flaps 45 and later stated that he believed he selected the landing gear down and observed three green lights indicating down and locked. The approach continued normally until touchdown, when the pilot felt a gentle contact, after which the aircraft skidded on its underside and propellers struck the runway. The aircraft slid to a stop. The pilot advised ATC, and airport rescue and firefighting services responded promptly. Four passengers and the pilot exited through the front left side window; one passenger exited through the main cabin door window.
Aircraft and System Details
The Cessna 402C is a twin-engine piston aircraft (2 TSIO-520-VB engines) manufactured in 1979. According to the Pilot’s Operating Handbook, the landing gear warning horn sounds intermittently when either throttle is retarded below approximately 13.0 inches Hg manifold pressure with the gear retracted, or when flaps are lowered past 15° with the gear not extended and locked. The system includes a press-to-test button on the annunciator panel to check the horn and indicator lights. Post-accident inspection revealed that the landing gear handle was in the down position, but the main and nose gear were found up and locked. Power application showed gear-up indication; the unlocked and transit lights were not illuminated. The emergency blow-down system subsequently produced three green lights. The landing gear warning horn was unserviceable due to a broken wire near the flap selector lever, an area subject to constant motion. It was not determined when the wire broke, but it likely failed during flap selection on the previous flight or the accident flight.
Checklists and Pilot Actions
The operator’s Operations Manual requires use of the Normal Procedures checklist. An abbreviated checklist was carried on all aircraft, including items for annunciator panel press-to-test before starting engines and landing gear down before landing. The operator issued a memo on 18 July 2021 reminding pilots to use the checklist. The pilot commented that he usually tests the warning horn and tries to use the checklist, but on the accident flight he probably did not use the checklist. Passengers reported not observing any pre-flight testing, checklist use, engine run-up, or safety briefing. One passenger did not hear the gear being lowered; another noted noise from gear on a subsequent return flight. During evacuation, some passengers struggled with exits; one initially tried the main cabin door but the stairs did not deploy due to the retracted gear. Smoke entered through an open window, causing concern. The pilot assisted passengers and was the last to exit.
Post-Accident Findings
Aircraft examination confirmed the landing gear was up and locked at touchdown. The landing gear warning horn was found unserviceable due to a broken wire. The pilot did not test the horn before the flight as prescribed. The Normal Procedures checklist, which includes items that might have alerted the pilot to the gear position, was not used during the flight.