Mid-Air of PSA Flight 182 and its Impacts on U. S. Aviation Lance Paston Utah Valley University Abstract
This paper reviews the tragic mid-air crash of PSA flight 182 and Cessna N7711G a Cessna 172 over San Diego and its resulting FAA rules and regulation changes, and their affect on the U. S. aviation industry. PSA Flight 182’s mid-air resulted in the most sweeping FAA changes to airspace to date. The FAA rules and regulation changes was a success in preventing similar mid-airs of this type.
On September 25, 1978, I was a 16-year-old inspiring young pilot going to high school within 10 miles of San Diego’s Lindbergh International Airport. It was about nine a. m. and clear skies when I noticed a large towering black cloud of smoke to the northwest. Minutes later, our High School Teacher informed us that two planes just collided over downtown San Diego. Pacific Southwest Airlines (PSA) flight 182, a Boeing 727-214 carrying 135 passengers collided with a Cessna 172 with two on board crashed 3 miles northeast of Lindbergh field over the San Diego community of North Park.
PSA flight 182 originated as a routine regularly scheduled early flight from Sacramento International with 35 PSA employees on board deadheading to San Diego. PSA flight 182 made a brief stop over at Los Angeles International before continuing on to San Diego Lindbergh (NTSB). PSA flight 182 was on a visual extended right downwind leg for runway 27 entering from Mission Bay (MZB) VORTAC and Cessna N7711G a Cessna 172M with an Instructor and licensed private pilot student practicing ILS approaches to runway 9 at Lindbergh, since Lindbergh was the only airport in the area equipped with an ILS at the time (University of Chicago Press).
The Cessna 172 just completed their second ILS approach and departed towards the northeast heading back to their home base of Montgomery Field. PSA flight 182 starting to make a descending right turn to base descended upon the Cessna impacting the right wing of the Boeing 727 and striking the nose and cockpit area of the Cessna causing it to brake apart and explode in-flight. PSA flight 182 suffered severe damage to its right wing rendering it virtually uncontrollable causing it to crash in a fire ball at a 50-degree right bank with a severe nose down attitude (Super70s. om) . The two main debris fields came to rest about 3,500 feet apart engulfing the neighborhood of North Park in fire and destroying about two dozen homes. PSA flight 182 was the worst aviation crash in history to that date and is still California’s worst to date killing 144 people, seven of which were on the ground and destroying or damaging 22 homes. According to the National Transportation Safety Board’s report, there were several mistakes that led up to and contributed to the mid-air collision, which could have been avoided.
Upon contacting San Diego Approach Control PSA, flight 182 was cleared for a visual to runway 29 with unknown traffic at twelve o’clock. The PSA aircrew initially was unable to make visual contact with the unknown traffic when approach again called out additional traffic at one O’clock a Cessna 172 three miles north of the field northeast bound out of 1,400 feet. Initially the PSA aircrew replied to approach that they had additional traffic in sight, approach then issued PSA a visual separation clearance (Macpherson).
However, it was later discovered according to cockpit tapes what was really going on was confusion among the PSA aircrew as to weather they ever had the Cessna in sight. They had lost sight of the Cessna and a discussion broke out in the PSA cockpit as to weather the Cessna had passed below and off their right wing prior to the Boeing starting their right turn to base. The PSA aircrew failed to let approach control know that they had lost visual contact with the Cessna or was not sure.
PSA flight 182 started their right turn to base thinking that the Cessna was already past them and was no longer a factor. While starting their turn the flight data recorder picked up a noise which initially sounded like a gear door closing, it was later determined this noise was the two aircraft colliding in mid-air at approximately 9:01 and 47 seconds. 19 seconds before the mid-air the controller received a conflict alert alarm in the tower indicating a possible aircraft conflict.
The controller subsequently ignored the alarm because he felt that since PSA flight 182 had acknowledged having the Cessna in sight and the controller felt that the aircrew of PSA flight 182 was meeting their requirement of visual separation, notification was not required in his opinion. The controller did try to notify the Cessna that PSA 182 had them in sight and that PSA 182 was eastbound at six o’ clock and descending.
There was no response from the Cessna as they had already switched frequencies as was being controlled by Miramar TRACON for the ILS approach procedures. The Cessna was unaware of the PSA flight coming from behind as the Cessna could only monitor one frequency at a time, unlike PSA flight 182 which was being controlled by Lindbergh tower had capabilities of monitoring both Lindbergh tower and Miramar TRACON (Time).
According to the National Transportation Safety Board, the mid-air was primarily the fault of the PSA aircrew for failing to maintain visual separation and not informing the tower that they had lost visual contact. Contributing factors were control tower procedures allowing controllers to use visual separation when radar separation of either vertical or lateral was available, failing to inform aircrews of conflict alarm within the control tower, and ignoring the conflict alarm.
I am amazed the National Transportation Safety Board did not address unnecessary talking in the PSA cockpit below 10,000 feet not related to landing. The early morning sun, which would have caused a glare on the windscreens of the aircraft making it harder to see each other was not addressed or the fact that Lindbergh, authorized the Cessna 172 to us an ILS approach to runway 9 while the active runway in use was runway 27 (NTSB).
This fact alone increases the potential future conflict of the two aircraft as they were both traveling east into the sun, the Cessna ascending and the Boeing descending with flaps, gear, slats extended with a nose high attitude trying to bleed off airspeed for landing (Wikipedia). At some point, the controllers should have been concerned because the Boeing would have to make a turn to base leaving both aircraft in each other’s blind spots getting ready to possibly turn into each other.
The FAA’s rules, regulations, and procedures instituted because of this horrific accident to insure that this type of accident would never happen again are as follows: The FAA immediately implemented a Terminal Radar Service Area at Lindbergh Field. The FAA issued new safety regulations requiring all unscheduled small commuter aircraft, charter and on demand, air taxis to be piloted by certified ATP licensed pilots and their aircraft to be equipped with cockpit voice recorders, ground warning systems, as well as thunderstorm detection equipment.
A review of procedures at all airports servicing air courier service mixed with general civil aviation aircraft of a dissimilar nature and requiring a Terminal Radar Service Area to protect the public at those airports as well. Discontinuing the use of visual separation 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 pilots of the Cessna failure to stay on its assigned course of 070 degrees instead changing to a heading of 090 degrees failing to notify controllers of that change (NTSB).
It was later determined that general aviation aircraft were left out of these new rules, so on May 15, 1980 the FAA started was is now known as “Class B airspace” around the nations busiest airports. Class B airspace as we know it today requiring all aircraft regardless of size to operated under radar control while within class B airspace and does not allow visual separation as was in effect during the PSA flight 182 mid-air collision.
In conclusion, I believe the FAA’s new rules and regulations borne out of this mid-air mishap were right on point and have served the commercial and general aviation communities well in preventing another mid-air crash of this type. I am in disagreement as to the contributing factors as I feel that controller actions and inactions played a larger role in this mishap than what the National Transportation Board acknowledges. References Macpherson, Malcom: The Black Box: All-New Cockpit Voice Recorder Accounts of in-flight Accidents.
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