What happened
On July 9, 2019, a TAROM ATR 42-500, registration YR-ATF, was completing the final segment of its daily flight schedule, arriving at Bucharest-Otopeni Airport from Satu Mare. The aircraft was carrying 22 passengers and 4 crew members.
During the landing on runway 08L, the aircraft made contact with the runway within the touchdown zone. Immediately after the wheels touched the ground, the pilot moved the engine power levers to the ground idle position. At this moment, the aircraft underwent intense deceleration accompanied by heavy vibrations and unusual noises. Nearby aircraft observed dense smoke emanating from the right main landing gear area.
The aircraft came to a halt approximately 560 meters down the runway. Upon inspection by emergency response teams, it was discovered that all tires and wheel rims of the main landing gear had been destroyed. Debris from the tires had also struck the landing gear doors and parts of the fuselage. There were no injuries among the passengers or crew, though the runway was temporarily closed to manage the incident.
The investigation
The investigation focused on the mechanical state of the braking system and the operational procedures followed by the crew. Investigators examined the hydraulic architecture of the aircraft, specifically the green and blue circuits, noting that while the antiskid system is functional during normal braking via the green circuit, it becomes inoperative when the emergency/parking brake handle is engaged.
Data analysis revealed that at the moment of runway contact, all main landing gear wheels were locked. This resulted in a significant peak deceleration of 0.45g immediately upon touchdown. The investigation also reviewed cockpit management, finding that the crew had not strictly adhered to the "sterile cockpit" concept during the flight and had performed landing checklists superficially.
Findings
- The incorrect position of the emergency/parking brake handle, which had been moved from the "OFF" position prior to touchdown, was the primary cause of the incident.
- The use of the emergency brake bypassed the antiskid valves, leading to immediate wheel lock-up upon contact with the runway.
- Crew performance was hindered by inefficient monitoring of on-board equipment and a failure to properly execute critical landing checklists.
- The crew did not fully comply with standard operating procedures regarding cockpit discipline during the descent phase.