1991 — March 21, Mid-Air Collision, US Navy P-3C’s, SW off San Diego Coast, CA — 27
— 27 Baugher. US Navy…Marine Corps BuNos Third Series (150139 to 156169). 10-29-2011.
— 27 Gero. Military Aviation Disasters: Significant Losses Since 1908. 1999, p. 154.
Narrative Information
Baugher: “Lockheed P-3C-150-LO Orion. 158930 (c/n 185-5602, VP-50) in midair collision with 159325 off coast of San Diego, CA Mar 21, 1991. All 27 on both planes killed.” (Baugher. US Navy…Marine Corps BuNos Third Series (150139 to 156169). 10-29-2011.)
Gero: “This disastrous mid-air crash occurred during an anti-submarine warfare training exercise. Designated as the ‘on-station’ aircraft, 159325 was being relieved by 158930, having provided sonobuoy contact as part of the operation. The two four- engine turboprop patrol aircraft collided at an approximate altitude of 3,000ft (1,000m) and some 60 miles (100km) south-west of San Diego, and both then plummeted into the Pacific Ocean [~2:15 a.m.]. All 27 crewmen from both aircraft, 14 aboard 158930 and 13 aboard 159325, lost their lives….
“Both aircraft had been based at the Moffett Field Naval Air Station, located near San Jose, California. The altitude separation to be used in the turn-over had been established in pre-flight briefings by their crews. Though both were operating under visual flight rules procedures, horizontal separation at the scene would have been afforded through air-to-air tactical air navigation (TACAN) facilities. In addition, the aircraft were in radio contact with each other.
“According to radar transcripts, 158930 had, prior to the accident, descended from its en-route altitude, and was maintaining its height, while 159325 had ascended an estimated 300 to 1,000ft (100-300m). Just before impact, the former was headed generally north, the latter generally east. The crew of a Navy helicopter observed the fireball produced by the collision. It was dark at the time, and the meteorological conditions consisted of intermittent rain, with the cloud level down to around 2,000ft (600m) and a visibility of between 5 and 10 miles (10-151cm). There was also thunderstorm activity in the area. The weather was considered a possible contributing factor.
“Although the exact sequence of events could not be determined, the accident apparently occurred after one crew either misunderstood the other’s intentions, lost situational awareness at a critical time, or violated a previous understanding or agreement made in radio communications as to how each P-3 would shift altitudes in order to effect the turn-over. Significantly, the flight of 159325 had been marked by equipment failures, an inoperative autopilot system, and extended time in turbulent weather conditions, which reportedly caused airsickness among some of its crewmen. These factors, combined with the added distractions of reported interference on its crew intercom system and fatigue associated with the length of time on station and the night-time duty, could have contributed to the accident had this crew been at fault. As previously mentioned, 159325 was the aircraft that deviated from the self-assigned swap height of 2,500ft (750m), although this could have been agreed upon between both crews by radio. Despite a recommendation for such, the investigative report noted no plans to retrofit the US Navy’s P-3 fleet with crash-survivable flight data recorders.” (Gero 1999, 154-155)
Sources
Baugher, Joseph F. US Navy and US Marine Corps BuNos Third Series (150139 to 156169). 3-31-2016 revision. Accessed at: 4-28-2016 at http://www.joebaugher.com/navy_serials/thirdseries19.html
Gero, David. Military Aviation Disasters: Significant Losses Since 1908. UK and Newbury Park, CA: Patrick Stephens Limited, an imprint of Hayes Publishing, 1999.