Abstract: The article titled “Mid-Air of PSA Flight 182 and its Impacts on U. S. Aviation” is written by Lance Paston from Utah Valley University.
This article discusses the catastrophic crash between PSA flight 182 and Cessna N7711G, a Cessna 172. It also explores the subsequent regulatory changes made by the FAA in response to this incident, which had a profound effect on the U.S. aviation industry. The collision of PSA Flight 182 led to extensive alterations being made to airspace regulations by the FAA, making it the most significant modification implemented thus far. These new rules and regulations effectively prevented any further occurrences of mid-air collisions.
On September 25, 1978, while attending high school near San Diego’s Lindbergh International Airport, I witnessed a large black cloud of smoke in the northwest around nine a.m. The news quickly spread that two planes had collided above downtown San Diego. The collision involved Pacific Southwest Airlines (PSA) flight 182, a Boeing 727-214 with 135 passengers on board, and a Cessna 172 carrying two individuals. This tragic crash happened three miles northeast of Lindbergh field in the North Park neighborhood of San Diego.
PSA flight 182, which had 35 PSA employees on board who were deadheading to San Diego, originated from Sacramento International as a routine early flight. Before reaching San Diego Lindbergh, the flight made a brief stopover at Los Angeles International. During its approach to runway 27 from Mission Bay (MZB) VORTAC, PSA flight 182 was on a visual extended right downwind leg. At the same time, a Cessna N7711G, a Cessna 172M with an Instructor and licensed private pilot student, was practicing ILS approaches to runway 9 at Lindbergh. This was because Lindbergh was the only airport in the area equipped with an Instrument Landing System (ILS) at that time.
The Cessna 172 completed its second ILS approach and headed back to Montgomery Field. Meanwhile, PSA flight 182 descended on a right turn towards its base and collided with the Cessna. The impact caused the Cessna to break apart and explode while severely damaging PSA flight 182’s right wing. The uncontrollable plane crashed in a fireball at a 50-degree right bank with a severe nose down attitude (Super70s.com). As a result, two debris fields were created about 3,500 feet apart, causing fires that destroyed around two dozen homes in North Park neighborhood. This tragic event marked the worst aviation crash in history up until that time and remains California’s deadliest incident to date. It claimed the lives of 144 individuals, including seven on the ground, while also destroying or damaging 22 homes. The National Transportation Safety Board’s report highlighted several avoidable mistakes leading to this mid-air collision.
Upon contacting San Diego Approach Control, flight 182 received clearance for a visual approach to runway 29. There was unknown traffic reported at twelve o’clock. Initially, the PSA aircrew could not visually identify the unknown traffic. Approach then notified them of additional traffic at one O’clock, specifically a Cessna 172 three miles north of the field, flying northeast bound at an altitude of 1,400 feet. The PSA aircrew initially informed approach that they had spotted the additional traffic. As a result, approach issued a visual separation clearance to PSA (Macpherson).
However, further investigation revealed that according to cockpit tapes, the confusion among the PSA aircrew stemmed from their uncertainty regarding whether they still had visual contact with the Cessna. The aircrew had lost sight of the Cessna, leading to a discussion in the PSA cockpit about whether the Cessna had passed beneath and to the right of their wing before the Boeing initiated its right turn towards base. Regrettably, the PSA aircrew neglected to inform approach control that they had lost visual contact with the Cessna or that they were unsure of its whereabouts.
PSA flight 182 initiated a right turn to base under the assumption that the Cessna had already passed them and was no longer a concern. As the turn began, the flight data recorder registered a sound resembling a gear door closing. However, it was later discovered that this noise was the result of the two aircraft colliding in mid-air at around 9:01:47. 19 seconds prior to the collision, the controller in the tower received a conflict alert alarm, signaling a potential aircraft conflict.
The controller chose to disregard the alarm because he believed that PSA flight 182 had confirmed visual contact with the Cessna. Thus, he considered the aircrew of PSA flight 182 to be fulfilling their obligation of maintaining visual separation, and he deemed communication unnecessary. However, the controller did attempt to inform the Cessna that PSA 182 had spotted them and was heading east at six o’clock while descending.
The Cessna did not respond because they had changed frequencies and were being controlled by Miramar TRACON for the ILS approach procedures. The Cessna did not know about the PSA flight approaching from behind because it could only monitor one frequency at a time. In contrast, PSA flight 182, which was being controlled by Lindbergh tower, could monitor both Lindbergh tower and Miramar TRACON.
According to the National Transportation Safety Board, the primary cause of the mid-air incident was the PSA aircrew’s failure to maintain visual separation and inform the tower about losing visual contact. Contributing factors included control tower procedures that permitted controllers to use visual separation instead of radar separation, failure to inform aircrews about conflict alarms in the control tower, and neglecting the conflict alarm.
The PSA cockpit below 10,000 feet should not engage in unnecessary talking unrelated to landing, according to the National Transportation Safety Board. The NTSB also failed to address the lack of information regarding the early morning sun, which could potentially create a glare on the aircraft windscreens and hinder visibility. Additionally, Lindbergh authorized the use of an ILS approach to runway 9 for the Cessna 172, despite the active runway being runway 27 (NTSB).
Wikipedia states that the possibility of conflict between the two aircraft grew because they were both flying eastward into the sun. The Cessna was going up, whereas the Boeing was descending and had extended flaps, gear, and slats to keep a high nose attitude in order to decrease airspeed for landing. It is probable that at some stage, controllers should have shown concern because the Boeing would have needed to make a turn towards base, resulting in both planes being in each other’s blind spots and potentially leading them to collide.
In response to the mentioned accident, the FAA has implemented a range of rules, regulations, and procedures aimed at preventing similar incidents in the future. These measures involve creating a Terminal Radar Service Area at Lindbergh Field and introducing new safety regulations. These regulations require certified ATP licensed pilots to operate unscheduled small commuter aircraft, charter flights, and on-demand air taxis. Additionally, these aircraft must be equipped with cockpit voice recorders, ground warning systems, and thunderstorm detection equipment.
A review of procedures at all airports servicing air courier service mixed with general civil aviation aircraft of a different nature and requiring a Terminal Radar Service Area to protect the public at those airports as well. There will no longer be visual separation used in terminal areas and terminal radar service areas, unless the pilot specifically requests it or when sequencing on final approach backed up with radar monitoring. The Cessna pilots failed to stay on the assigned course of 070 degrees and instead changed to a heading of 090 degrees without notifying controllers of that change (NTSB).
The FAA discovered that the new rules did not include general aviation aircraft. As a result, on May 15, 1980, they established what is currently referred to as “Class B airspace” around the busiest airports in the country. This type of airspace mandates that all aircraft, regardless of size, must operate under radar control while within Class B airspace. Additionally, visual separation, which was allowed during the PSA flight 182 mid-air collision, is not permitted.
To summarize, I support the FAA’s new rules and regulations in preventing mid-air accidents. Nonetheless, I disagree with the National Transportation Board’s evaluation of the contributing factors, as I believe air traffic controllers’ actions had a more substantial impact. Macpherson’s book “The Black Box: All-New Cockpit Voice Recorder Accounts of in-flight Accidents” supports this viewpoint.
The following html tags and their contents contain information about the sources and references related to the topic:
New York: William Morrow, 1998 National Transportation Safety Board (NTSB) Aircraft Accident Report, Adopted Apr 20, 1979 Super70s. com, Retrieved Oct 1, 2009: http://www. super70s. com/super70s/tech/aviation/disasters/78-09-25(PSA). asp Time, Retrieved Oct 1, 2009: http://www. time. com/time/magazine/article/0,9171,919842-1,00. html University of Chicago Press, Clashes and Aircraft Crashes, Chicago, 1997 Wikipedia, Retrieved Oct 2, 2009: http://en. wikipedia. org/wiki/PSA_Flight_182
