Multiple people were killed Thursday when two small planes collided in midair as they attempted to land at a municipal airport in Northern California, according to authorities.
One person was onboard the Cessna 152 and two people were on the Cessna 340, the agency said.
Images from the scene about 45 miles south of San Jose showed the mangled wreckage of the single-engine craft in a grassy field near the airport. The Cessna 340, which is larger and can carry up to five passengers, appeared to smash through the metallic walls of an airport building, sending plumes of black smoke rising into the air. No injuries were reported on the ground.
“We are grieving tonight from this unexpected and sudden loss,” Watsonville Mayor Ari Parker said in a statement. “I want to express my deepest and most heartfelt condolences.”
The FAA and the National Transportation Safety Board are investigating the crash.
Midair collisions are rare, with fewer than 30 happening in a typical year, according to aviation safety data. They almost always involve small private planes, like the two that collided in Watsonville, or military aircraft, not large commercial airliners.
Hundreds more near-midair collisions are reported annually; the FAA defines these incidents as the “possibility of a collision” when pilots are less than 500 feet apart, or when a collision hazard is reported by a pilot or flight crew member.
Heavy air traffic is a risk factor for collisions, which happen more frequently around busy airports. Other causes include navigation issues, high approach speeds and miscommunication. The FAA says many collisions occur in favorable weather and during daylight hours, and often happen when pilots are coming in for a landing. Generally these crashes are the result of human error, according the FAA.
“In most cases, at least one of the pilots involved could have seen the other in time to avoid contact, if he or she had just been using the visual senses properly,” the agency says in guidance on its website. “In sum, it is really that complex, vulnerable little organ — the human eye — which is the leading cause of inflight collisions.”
Transportation regulations require pilots to “see and avoid” other aircraft when weather permits. Pilots are instructed to keep a “vigilant lookout,” paying close attention to airport takeoff and landing procedures and refocusing their eyes when shifting views, according to the FAA.
The Watsonville airport was last inspected in May, according to a report listed in the FAA’s airport data and information portal. The inspection did not appear to highlight any hazards that would raise the risk of collisions in the skies over the facility.
The airport houses 280 aircraft, according to the report, including 256 single-engine planes, 15 multi-engine aircraft and several helicopters.
In 2011, two people were killed after a single-engine plane took off from the Watsonville airport, quickly nosedived into the parking lot of a community hospital and skidded into the building. Investigators later found that the pilot, who was licensed to fly by visual cues only, appeared to have taken off toward a patch of fog, then abruptly changed course.