PSA Flight 182

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Pacific Southwest Airlines Flight 182
A photo taken of N533PS seconds after collision with Cessna 172
Accident summary
Date September 25, 1978
Summary Mid-air collision resulting from pilot error and ATC error
Site San Diego, California
Total injuries (non-fatal) 9 (on ground)
Total fatalities 144 (7 on ground)
Total survivors 0
First aircraft
Type Boeing 727-214
Operator PSA
Registration N533PS
Flight origin Sacramento Int'l Airport
Stopover Los Angeles Int'l Airport
Destination San Diego Int'l Airport
Passengers 128
Crew 7
Survivors 0
Second aircraft
Type Cessna 172
Operator Gibbs Flite Center, Inc.[1]
Registration N7711G
Flight origin Montgomery Field
San Diego, California[1]
Crew 2
Survivors 0

Pacific Southwest Airlines (PSA) Flight 182, registration N533PS, was a Boeing 727-214 commercial airliner that collided with a private Cessna 172 over San Diego, California on September 25, 1978. It was Pacific Southwest Airlines' first accident involving fatalities. The death toll of 144 makes it the deadliest aircraft disaster in California history. Until the crash of American Airlines Flight 191, it was also the deadliest plane crash in U.S. aviation history.

Both aircraft crashed into North Park, a San Diego neighborhood, killing all 137 people on both aircraft and seven people on the ground in houses, including two children. Nine others on the ground were injured and 22 homes were destroyed or damaged by the impact and the spreading of debris.

The PSA 182 accident caused the revision of air traffic rules applicable to the busiest airports across the U.S., with the intention of improving separation of aircraft operating in the vicinity of large airports.[citation needed]

Accident[edit]

Pacific Southwest Airlines Flight 182 was a popular early-morning commuter flight terminating at San Diego's Lindbergh Field. The flight originated in Sacramento on Monday, September 25, 1978, with a stopover in Los Angeles. At the controls were 42-year-old Captain James E. McFeron, 38-year-old Co-Pilot Robert E. Fox, and 44-year-old Flight Engineer Martin J. Wahne. Captain McFeron was a seasoned pilot with nearly 14,400 flight hours to his credit. He was a hugely experienced Boeing 727 pilot, having logged close to 10,500 hours in them. First Officer Fox and Flight Engineer Wahne were also very experienced, having accumulated approximately 10,000 total flight hours and 10,800 total flight hours, respectively. They, too, were very familiar with the Boeing 727, having logged 5,800 hours and approximately 6,600 hours of flight time in the aircraft type.

As they neared the end of their flight in full sunlight and clear weather conditions, with visibility extending 10 miles (16 km), the PSA crew was alerted by the approach controller about a small Cessna 172 Skyhawk aircraft nearby. The Cessna was being flown by two licensed pilots. One was 32-year-old Martin B. Kazy Jr., who possessed single-engine, multi-engine and instrument flight ratings, as well as a commercial certificate and an instrument flight instructor certificate. He had flown a total of 5,137 hours. The other, 35-year-old David Boswell, a U.S. Marine Corps sergeant, possessed single-engine and multi-engine ratings and a commercial certificate. He had flown just 407 hours and, at the time of the accident, was practicing ILS approaches under the instruction of Kazy in pursuit of his instrument rating. They had departed from Montgomery Field, and were navigating under VFR, which did not require the filing of a flight plan. Boswell was wearing a "hood" to limit his field of vision straight ahead to the cockpit panel, much like an oversize sun visor with vertical panels to block peripheral vision, as is normal in IFR training.

Abridged communication between PSA 182 and the controllers, and among the PSA flight crew
# = Nonpertinent word; * = Unintelligible word (); = Questionable text; (()) = Commentary; Shading = Radio communication
Time Source Content
08:59:39 San Diego
approach control
PSA one eighty-two, additional traffic's ah, twelve o'clock, three miles ((five km))
just north of the field, northeast-bound, a Cessna
one seventy-two climbing VFR out of one thousand four hundred
08:59:39 Flight engineer Yeah ((Sound of laughter))
08:59:39 First officer Very nice
08:59:41 Flight engineer He really broke up laughing
I said so I'm late
08:59:48 ((Off-duty captain relays an anecdote until 09:00:10))
08:59:50 First officer (to San Diego
approach control)
Okay we've got that other twelve.
08:59:57 San Diego
approach control
Cessna seven seven one one golf, San Diego departure radar contact,
maintain VFR conditions at or below three thousand five hundred,
fly heading zero seven zero, vector final approach course.
09:00:15 San Diego approach control PSA one eighty-two, traffic's at twelve o'clock, three miles out of one thousand seven hundred.
09:00:21 First officer Got 'em.
09:00:22 Captain (to San Diego
approach control)
Traffic in sight.
09:00:26 First officer Flaps two.
09:00:34 Captain (to Lindbergh tower) Lindbergh, PSA one eighty-two downwind.
09:00:38 Lindbergh tower PSA one eighty-two, Lindbergh tower, ah, traffic twelve o'clock one mile a Cessna.
09:00:41 First officer Flaps five.
09:00:42 Captain Is that the one (we're) looking at?
09:00:43 First officer Yeah, but I don't see him now.
09:00:44 Captain (to Lindbergh tower) Okay, we had it there a minute ago.
09:00:47 Lindbergh tower One eighty-two, roger.
09:00:50 Captain (to Lindbergh tower) I think he's pass(ed) off to our right.
09:00:51 Lindbergh tower Yeah.
09:00:52 Captain He was right over here a minute ago.
09:00:53 First officer Yeah.

The PSA pilots reported that they saw the Cessna after being notified of its position by ATC, although cockpit voice recordings revealed that shortly thereafter the PSA pilots no longer had the Cessna in sight and they were speculating about its position. Lindbergh tower heard the 09.00:50 transmission as "He's passing off to our right" and assumed the PSA jet had the Cessna in sight.

After getting permission to land, and about 40 seconds before colliding with the Cessna, the conversation among the four occupants of the cockpit (captain, first officer, flight engineer and the off-duty PSA captain, Spencer Nelson, who was riding in the cockpit's jump seat) was as follows, showing the confusion:

# = Nonpertinent word * = Unintelligible word () = Questionable text (()) = Commentary
Time Source Content
09:01:07 Lindbergh tower PSA one eighty-two, cleared to land.
09:01:08 Captain (to Lindbergh tower) One eighty-two's cleared to land.
09:01:11 First officer Are we clear of that Cessna?
09:01:13 Flight engineer Suppose to be
09:01:14 Captain I guess
09:01:15 First officer (Fifteen)
Between 09:01:15 and 20 Unknown ((Sound of laughter))
09:01:20 Off-duty captain I hope
09:01:21 Captain Oh yeah, before we turned downwind,
I saw him at about one o'clock,
probably behind us now

Actually, the Cessna was directly in front of and below the Boeing, and the PSA plane was descending and rapidly closing in on the small plane, which had taken a right turn to the east, deviating from the assigned course. According to the report issued by the National Transportation Safety Board (NTSB), the Cessna may have been a difficult visual target for the jet's pilots, as it was below them and blended in with the multicolored houses of the residential area beneath; the Cessna's fuselage was yellow, and most of the houses were a yellowish color. Also, the apparent motion of the Cessna as viewed from the Boeing was minimized, as both planes were on approximately the same course. The report said that another possible reason that the PSA aircrew had difficulty observing the Cessna was that its fuselage was made visually smaller due to foreshortening. However, the same report in another section also stated that "the white surface of the Cessna's wing could have presented a relatively bright target in the morning sunlight."

A visibility study cited in the NTSB report concluded that the Cessna should have been almost centered in the windshield of the Boeing from 170 to 90 seconds before the collision, and thereafter it was likely positioned on the lower portion of the windshield just above the windshield wipers. The study also said that the Cessna pilot would have had about a 10-second view of the Boeing from the left-door window about 90 seconds before the collision, but visibility of the overtaking jet was blocked by the Cessna's ceiling structure for the remainder of the time.

Flight 182's crew never explicitly alerted the tower that they had lost sight of the Cessna. If they had made this clear to controllers, the crash might not have happened. Also, if the Cessna had maintained the heading of 70 degrees assigned to it by ATC instead of turning to 90 degrees, the NTSB estimates the planes would have missed each other by about 1000 feet (300 meters) instead of colliding. Ultimately, the NTSB maintained that regardless of that change in course, it was the responsibility of the crew in the overtaking jet to comply with the regulatory requirement to pass "well clear" of the Cessna.

Approach Control on the ground picked up an automated conflict alert 19 seconds before the collision but did not relay this information to the aircraft because, according to the approach coordinator, such alerts were commonplace even when there was no actual conflict. The NTSB stated: "Based on all information available to him, he decided that the crew of Flight 182 were complying with their visual separation clearance; that they were accomplishing an overtake maneuver within the separation parameters of the conflict alert computer; and that, therefore, no conflict existed."

This was the conversation in the PSA cockpit starting 16 seconds prior to collision with the Cessna:

# = Nonpertinent word * = Unintelligible word () = Questionable text (()) = Commentary
Time Source Content
09:01:31 First officer Gear down
09:01:34 ((Clicks and sound similar to gear extension))
09:01:38 First officer There's one underneath
09:01:39 Unknown *
09:01:39 First officer I was looking at that inbound there
09:01:42 ((Sound of thump similar to nose gear door closing))
09:01:45 Captain Whoop!
09:01:46 First officer Aaargh!
09:01:47 ((Sound of impact))
09:01:47 Off-duty captain Oh # #

PSA Flight 182 overtook the Cessna, which was directly below it, both approximately on a 090 (due east) heading. The collision occurred at approximately 2,600 feet (790 m) and broke the Cessna, and the 727's right wing and empennage, to pieces.[1] According to several witnesses on the ground, there was first a loud metallic "crunching" sound, then an explosion and fire that drew them to look up.

Staff photographer Hans Wendt of the San Diego County Public Relations Office was attending an outdoor press event with a still camera, and was able to take two post-collision photographs of the falling 727, its right wing burning.[2] Cameraman Steve Howell from local TV channel 39 was attending the same event, and captured the Cessna on film as it fell to earth, the sound of the impacting 727 and the mushroom cloud from the resulting crash. For its coverage of the disaster, The San Diego Evening Tribune, a predecessor to The San Diego Union-Tribune, was awarded a Pulitzer Prize in 1979 for "Local, General, or Spot News Reporting".[3]

The wreckage of the Cessna plummeted to the ground, its vertical stabilizer torn from its fuselage and bent leftward, its debris hitting around 3,500 feet (1,100 m) northwest of where the 727 went down. PSA 182's right wing was heavily damaged, rendering the plane uncontrollable and sending it careening into a sharp right bank (clearly seen in the Wendt photos), and the fuel tank inside it ruptured and started a fire, when this final conversation took place inside the cockpit:

# = Nonpertinent word * = Unintelligible word () = Questionable text (()) = Commentary
Time Source Content
09:01:48 Unknown #
09:01:49 Captain Easy baby, easy baby
09:01:50 Unknown Yeah
09:01:51 ((Sound of electrical system reactivation tone on voice recorder,
system off less than one second))
09:01:51 Captain What have we got here?
09:01:52 First officer It's bad
09:01:52 Captain Huh?
09:01:53 First officer We're hit man, we are hit
09:01:55 Captain (to Lindbergh tower) Tower, we're going down, this is PSA
09:01:57 Lindbergh tower OK, we'll call the equipment for you
09:01:58 Unknown Whoo!
09:01:58 ((Sound of stall warning))
09:01:59 Unknown Bob!
09:01:59 Captain (to Lindbergh tower) This is it, baby!
09:02:00 First officer # # #
09:02:01 Unknown # #
09:02:03 Captain (on intercom, to passengers) Brace yourself
09:02:04 Unknown Hey, baby *
09:02:04 Unknown Ma, I love ya
09:02:04.5 ((Electrical power to recorder stops))
PSA 182 crash site as it appeared in 2010. Looking west down Dwight St., Nile Street intersection is in foreground; Boundary St. intersection in background. The initial impact was about 30 feet to the right of the photographer, on Nile St.

Flight 182 impacted a house 4830 meters (three miles) northeast of Lindbergh Field, in a residential section of San Diego known as North Park. It impacted at a 300 mph (480 km/h), nose-down attitude while banked 50° to the right. Seismographic readings indicated that the impact occurred at 09:02:07, about 2.5 seconds after the cockpit voice recorder lost power. The plane impacted just west of the I-805 freeway, approximately nine meters (30 feet) north of the intersection of Dwight and Nile streets, with the bulk of the debris field spreading in a northeast to southwesterly direction towards Boundary Street. One of the plane's wings lodged in a house. The coordinates for the Boeing crash site are 32°44′37″N 117°07′14″W / 32.74361°N 117.12056°W / 32.74361; -117.12056Coordinates: 32°44′37″N 117°07′14″W / 32.74361°N 117.12056°W / 32.74361; -117.12056. The largest piece of the Cessna impacted about six blocks away near 32nd St. and Polk Ave. The coordinates for the Cessna crash site are 32°45′7.97″N 117°7′32.57″W / 32.7522139°N 117.1257139°W / 32.7522139; -117.1257139. The explosion and fire from the 727 crashing created a mushroom cloud that could be seen for miles (and was photographed and filmed), Approximately 60% of the entire San Diego Fire Department was ultimately dispatched to the scene, and first responders said nothing resembling an airplane was anywhere to be seen, since the impact, explosion, and fires had destroyed the 727 with no sizable components remaining except the engines, empennage, and landing gear.[2] On the other hand, the impact and debris area was relatively small due to the plane's steep, nose-down angle.

In total, 144 people[4] lost their lives in the disaster, including Flight 182's seven crew members, 30 additional PSA employees[5] deadheading to PSA's San Diego base, the two Cessna occupants, and seven residents (five women, two male children) on the ground. Among the victims on board PSA Flight 182 were Alan Tetelman, professor of metallurgy at UCLA and president of Failure Analysis Associates (now Exponent), who was en route to investigate a U.S. Navy helicopter crash; Charles Dunsmoor Bren, the 34-year-old son of actress Claire Trevor Bren; Richard "Ric" Horne, the 51-year-old brother of American mezzo-soprano opera singer Marilyn Horne; and Valerie Woods Kantor, the first wife of future United States Secretary of Commerce Mickey Kantor. An additional nine people on the ground were injured, and 22 homes across a four-block area were destroyed or damaged. One potential passenger, Jack Ridout, a survivor of the Tenerife airport disaster the year before, had also booked a ticket on Flight 182 from Los Angeles, but cancelled his booking to leave for home the day before.[6]

The accident was notable for the extreme carnage it created, as the entire crash site was strewn with human remains. An officer from the San Diego Police Academy assigned to work the scene that day said that "There were no bodies to speak of - only pieces. One alley was just filled with arms, legs, and feet... I was no stranger to dead bodies, but I wasn't ready to see the torso of a stewardess slammed against a car.... The heat of the fires and the sun made the whole scene surreal. We couldn't drink enough water. All around us was the stench of kerosene and burning flesh. We did our job by rote, locating the pieces so the SWAT team could mark the spot and cover the body parts".[7]

Investigation[edit]

Sequence of events leading to the collision, X - PSA 182 ♦ - Cessna 172

At the nearby St. Augustine High School, a triage and command and control center was established, with its gymnasium being used as a makeshift morgue and for forensic investigation. [8][citation needed] Freezer units were used to preserve the biological remains, as San Diego was in the middle of a severe heat wave, with temperatures exceeding 100 °F (37 °C).

National Transportation Safety Board report number NTSB/AAR-79-05,[1] released April 19, 1979, determined that the probable cause of the accident was the failure of the PSA flight crew to follow proper air traffic control (ATC) procedures. Flight 182's crew lost sight of the Cessna in contravention of the ATC's instructions to "keep visual separation from that traffic", and did not alert ATC that they had lost sight of it. Errors on the part of ATC were also named as contributing factors, including the use of visual separation procedures when radar clearances were available. Additionally the Cessna pilots, for reasons unknown, did not maintain their assigned east-northeasterly heading of 070 degrees after completing a practice instrument approach, nor did they notify ATC of their course change. Concerning this the NTSB report states, "According to the testimony of the controllers and the assistant chief flight instructor of the Gibbs Flite Center (owner of the Cessna), the 08:59:56 transmission from approach control to the Cessna only imposed an altitude limitation on the pilot, he was not required to maintain the 070° heading. However, the assistant chief flight instructor testified that he would expect the [Cessna] pilot to fly the assigned heading or inform the controller that he was not able to do so."

A dissenting opinion in the NTSB crash report by member Francis H. McAdams strongly questioned why the unauthorized change in course by the Cessna was not specifically cited as a "contributing factor" in the final report; instead, it was listed as simply a "finding", which carries less weight. McAdams also "sharply disagreed" with the majority of the panel on other issues, giving more weight to inadequate ATC procedures as another "probable cause" to the accident, rather than merely treating them as a contributing factor. McAdams also added the "possible misidentification of the Cessna by the PSA aircrew due to the presence of a third unknown aircraft in the area" as a contributing factor. The majority panel members did not cite this as a credible possibility. In an August 1982 amendment to the probable cause finding, the NTSB adopted McAdams’ viewpoints regarding both ATC and pilot failings.[9]

The report states that in the PSA cockpit, some conversation in the cockpit was not relevant to the flight during critical phases of the flight. The report states that the conversation was not a causal factor in the accident but that "it does point out the dangers inherent in this type of cockpit environment during descent and approach to landing."[1]

The two photographs of Flight 182 taken by Hans Wendt revealed that the left wing flaps were extended as the crew tried hopelessly to steer the crippled aircraft and that the right wing had a large piece missing where the Cessna had struck. Although it was obvious that the flaps were damaged or destroyed from the collision, NTSB investigators could not determine the condition of the hydraulic system in the wing and whether the plumbing inside it had actually been ruptured or merely flattened. Since the right wing was extremely fragmented, examination of debris provided no useful information. It was thought that the crew may have tried to guide the 727 away from impacting a residential area and onto Route 805 where damage would be lessened, but could not do so, and the final conclusion of the NTSB was that even if the hydraulic lines in the right wing were undamaged, the missing flaps and spreading fire would have adversely affected the plane's aerodynamic profile and in all likelihood, Flight 182 was completely uncontrollable post-collision.[1]

Aftermath[edit]

In the aftermath of the devastation on the ground, a controversy renewed in San Diego over the placement of such a busy airport in a heavily populated area. Despite proposals to relocate it, San Diego International Airport, the busiest single-runway commercial airport in the U.S., remains in use.[10]

At the time, PSA Flight 182 was the U.S.'s deadliest commercial air disaster, and it remains the worst in California's history. As mentioned above, the former distinction was surpassed eight months later on Friday, May 25, 1979, when American Airlines Flight 191 (a McDonnell Douglas DC-10) crashed in Chicago, Illinois. The crash of Flight 191 resulted in 273 deaths (all 271 on the plane and 2 on the ground) - nearly double the number caused by Flight 182's crash.

As a result of the crash, the NTSB recommended the immediate implementation of a Terminal Radar Service Area around Lindbergh Field to provide for the separation of aircraft, as well as an immediate review of control procedures for all busy terminal areas. This initial rule did not include small general aviation aircraft. Therefore, on May 15, 1980, the Federal Aviation Administration (FAA), implemented what is called Class B airspace to provide for the separation of all aircraft operating in the area. Additionally, all aircraft, regardless of size, are required to operate under "positive radar control," a rule that allows only radar control from the ground for all aircraft operating in the airport's airspace.[4]

At the time of the crash, Lindbergh Field was the only airport in San Diego County with an Instrument Landing System. Since the Cessna pilot was practicing instrument landings, the FAA quickly installed the system at Montgomery and Gillespie fields, and at McClellan-Palomar Airport, in order to allow pilots to practice at smaller airports.[4]

As a result of this and other mid-air collisions (including an almost identical one in 1986) the "Traffic Collision Alert and Avoidance System" (TCAS) is now installed in all commercial passenger aircraft and in most commercial cargo airplanes. TCAS gives the pilots visual and audible warnings in the cockpit when two aircraft are approaching each other, and directs pilots to either climb or descend to avoid the other aircraft.

Because the PSA 182/Cessna collision was the result of pilot error, it is used as a teaching aid in modern flight training. Some flight schools use the crash in "human factors" classes, others refer to it while teaching airspace or visual separation rules.[4]

The midair collision contributed to Lindbergh Field airport being ranked 10th among the world's Most Extreme Airports in a two-hour documentary of the same name released in July 2010, which aired in the U.S. on the History Channel.

Memorials[edit]

Plaque honoring crash victims

A memorial plaque honoring those who died on both planes and on the ground is located in the San Diego Aerospace Museum, near the Theodore Gildred Flight Rotunda in San Diego's Balboa Park. On the 20th anniversary of the crash, a tree was planted next to the North Park branch library, and a memorial plaque was dedicated to those who lost their lives. The library is not in the immediate vicinity of the actual crash site, which is completely rebuilt and bears no visible evidence of the crash.

On September 25, 2008, over 100 relatives and friends of the victims of PSA 182 gathered at Dwight and Nile streets in North Park for a 30th anniversary memorial of the crash.[11]

Prior telemovie[edit]

In a case of life imitating art, the NBC telemovie Emergency!: Survival on Charter #220 (effectively a two-hour Emergency! episode filmed after the show was no longer a weekly series) had aired in March 1978, six months before the accident involving PSA Flight 182. It detailed the accidental daytime mid-air collision of a Douglas DC-8 airliner, and a much smaller two-person aircraft and the resulting crash and carnage in a residential area of Los Angeles County.

Dramatization[edit]

The accident was covered in Mayday's season 11 episode "Blind Spot" (alternatively "On Course To Disaster" in the UK and "Hiding in Plane Sight" in Australia).

See also[edit]

References[edit]

External links[edit]