Iberia Airlines Flight 933 was an international flight from Madrid Barajas International Airport bound for its destination, Boston-Logan International Airport in Boston, that suffered a runway incident on December 17, 1973. As the McDonnell Douglas DC-10, the aircraft operating the flight was approaching the airport, it collided with the ALS system 500 feet short from the runway threshold. This critically damaged the frontal gear, collapsing it. The aircraft came to a rest 300 feet before the runway. Although all 168 onboard survived, the plane was written off. This accident was the first hull loss of the DC-10.