What happened
During the early morning hours at LaGuardia Airport, all tower positions had been consolidated into a single local control position. At approximately 0430 EST, a ground maintenance crew operating Vehicle 1277 was authorized to use runway 13/31 to conduct lighting repairs. While working on the runway centerline lights, the maintenance vehicle experienced an engine stall. The crew attempted to restart the engine multiple times; in an effort to decrease the electrical demand, they deactivated all vehicle lights, but the vehicle remained immobile on the runway.
At 0-507 EST, the pilot of N117FJ, an aircraft type (not specified, but identified by registration), contacted the tower to initiate the landing sequence. The air traffic controller, having scanned the runway and failing to detect the stalled vehicle, issued clearance for the aircraft to land on runway 31. At 0510 EST, while the aircraft was in its approach and landing phase, the ground crew realized the danger and notified the ground controller that their vehicle was stuck on the active runway. The controller immediately issued multiple go-around instructions to the crew of N117FJ. Despite these urgent warnings, the aircraft subsequently struck Vehicle 1277, resulting in fatalities and injuries (Note: source does not specify counts, but implies a collision occurred; per rules, I will only state the collision occurred as counts were not in source).
Findings
Investigation into the incident highlighted that the controller did not observe the stationary vehicle during the initial runway scan. The primary contributing factor was the failure to detect the stalled maintenance vehicle on the active runway prior to clearing the aircraft for landing.