L-410 MA OM-SAB Gear-Up Landing at Příbram-Dlouhá Lhota

Incident Overview On 4 December 2004, an L-410 MA aircraft, registration OM-SAB, operated by Dubnica Air, s.r.o., made a gear-up landing on the asphalt surface of runway 060 at Příbram-Dlouhá Lhota (LKPM). The aircraft came to rest on the centerline of runway 24. No injuries were reported to the crew, passengers, or other persons, and no other damage occurred. ## Flight Details The crew was conducting a parachute test drop flight, releasing dummies from passes along runway 060 at altitudes of 200 and 350 meters. After the second pass, the crew continued on a left circuit to the final approach for runway 24. The AFIS dispatcher radioed the pilots about persons crossing the runway. The pilots confirmed this information to each other via intercom, but their subsequent intercom discussion about the situation masked the dispatcher's warning about the landing gear being retracted. The pilots focused on the persons on the runway and did not extend the gear. A later transmission from the AFIS dispatcher warning about the retracted gear was overmodulated and unintelligible, and was not received by the pilots. The pilots heard the warning tone for the retracted gear only shortly before touchdown, when they moved the engine power levers to idle during the flare. They realized their error, but it was too late to correct it. ## Aircraft and Crew The aircraft was an L-410 MA, serial number 750405, manufactured by Letecké závody, a.s. Kunovice in 1975. At the time of the incident, it had accumulated 4,432 flight hours and 9,819 landings. The aircraft had valid operating documents, and its technical condition did not contribute to the accident. Maintenance was performed according to the manufacturer's procedures. Both pilots held valid qualifications and medical fitness for the flight. The pilot-in-command had a total of 13,500 flight hours and 44,000 landings, with 5,000 hours and 4,800 landings on the L-410. The first officer had a total of 837 flight hours and 2,254 landings, with 150 hours and 386 landings on the L-410. A preliminary breath test found no alcohol influence on the pilots. Technicians on board operating the test drops did not contribute to the accident. ## Environmental and Operational Factors The weather was CAVOK, with wind from 240° at 4-5 m/s, suitable for the operation. The condition of the airport did not contribute to the accident. The operator held a valid permit for aerial work at the time of the accident. ## Findings and Cause The investigation found that the crew did not have checklists available in the cockpit and did not perform the pre-landing procedures thoroughly. The probable cause of the accident was the crew's failure to extend the landing gear. Due to the absence of checklists in the cockpit, the crew was unable to perform a complete check of the aircraft's readiness for landing. ## Safety Recommendations The investigation recommended that checklists be provided on board the aircraft for the flight crew. Further measures were left to the operator's discretion.