Operator Image

Crash of a Boeing 747-121A in Lockerbie: 270 killed

Date & Time: Dec 21, 1988 at 1903 LT
Type of aircraft:
Operator:
Registration:
N739PA
Flight Phase:
Survivors:
No
Site:
Schedule:
London - New York
MSN:
19646
YOM:
1970
Flight number:
PA103
Region:
Crew on board:
16
Crew fatalities:
Pax on board:
243
Pax fatalities:
Other fatalities:
Total fatalities:
270
Captain / Total flying hours:
10910
Captain / Total hours on type:
4107.00
Copilot / Total flying hours:
11855
Copilot / Total hours on type:
5517
Aircraft flight hours:
72464
Aircraft flight cycles:
16497
Circumstances:
Flight PA103 departed London-Heathrow runway 27R for New York at 18:25. The aircraft levelled off at FL310, 31 minutes later. At 19:03 Shanwick Oceanic Control transmitted an oceanic clearance. At that time an explosion occurred in the aircraft's forward cargo hold at position 4L. The explosive forces produced a large hole in the fuselage structure and disrupted the main cabin floor. Major cracks continued to propagate from the large hole while containers and items of cargo ejected through the hole, striking the empennage, left- and right tail plane. The forward fuselage and flight deck area separated when the aircraft was in a nose down and left roll attitude, peeling away to the right at Station 800. The nose section then knocked the no. 3 engine off its pylon. The remaining aircraft disintegrated while it was descending nearly vertically from 19000 feet to 9000 feet. A section of cabin floor and baggage hold (from approx. Station 1241-1920) fell onto housing at Rosebank Terrace, Lockerbie. The main wing structure struck the ground with a high yaw angle at Sherwood Crescent, Lockerbie causing a massive fire. The Semtex bomb which caused the explosion had probably been hidden in a radio cassette player and was transferred to PA103 from a Pan Am Boeing 727 flight, arriving from Frankfurt. After a three-year joint investigation by the Dumfries and Galloway Constabulary and the U.S. Federal Bureau of Investigation indictments for murder were issued on November 13, 1991, against Abdel Basset Ali al-Megrahi, a Libyan intelligence officer and the head of security for Libyan Arab Airlines (LAA), and Lamin Khalifah Fhimah, the LAA station manager in Luqa Airport, Malta. United Nations sanctions against Libya and protracted negotiations with the Libyan leader Colonel Muammar al-Gaddafi secured the handover of the accused on April 5, 1999. On January 31, 2001, Megrahi was convicted of murder by a panel of three Scottish judges, and sentenced to 27 years in prison. Fhimah was acquitted.
Probable cause:
The in-flight disintegration of the aircraft was caused by the detonation of an improvised explosive device located in a baggage container positioned on the left side of the forward cargo hold at aircraft station 700.
Final Report:

Crash of a Boeing 747-121 in Karachi

Date & Time: Aug 4, 1983 at 0438 LT
Type of aircraft:
Operator:
Registration:
N738PA
Survivors:
Yes
Schedule:
New Delhi – Karachi – London – New York
MSN:
19645
YOM:
1970
Flight number:
PA073
Country:
Region:
Crew on board:
16
Crew fatalities:
Pax on board:
227
Pax fatalities:
Other fatalities:
Total fatalities:
0
Aircraft flight hours:
53324
Circumstances:
Flight PA073 was cleared to land on runway 25R of Karachi International Airport (KHI), Pakistan. The approach speed just prior to touchdown was 152 knots. After touchdown reverse thrust was applied on engines n°1, 2 and 3. Engine No.4 which had an unserviceable reverser was left in forward idle. Seventy knots was called and some three seconds later reverse power was decreased. At this stage EPR on n°4 engine increased rapidly. The aircraft veered to the left of the centerline at about 7400 feet from the approach end of runway 25R and departed the runway edge at 8000 feet from the approach end of runway 25R with 2,500 feet of runway remaining. Shortly before the aircraft departed the runway, the pilot flying (copilot) reported that he had no brakes and no nose wheel steering. The captain stated that he got on the brakes and tiller at this time to assist. After departing the runway surface the aircraft travelled 380 feet through soft mud before it came to rest at a point about 2100 feet from the end of runway 25R, heading about 160 degrees on the Southern side of the runway with the tail of the aircraft 120 feet from the runway edge. Shortly after the aircraft departed the runway, the nose gear struck a VASI light installation and its concrete base causing the nose gear to collapse backwards and to the left, resulting in total destruction of the VASI light installation and damage to the forward cargo hold, floor of the first class section and the stairway leading to the upper deck. Damage to the aircraft was substantial and it was not repaired. All 243 occupants evacuated safely.
Source: ASN
Probable cause:
Loss of directional control as the result of inadvertent application of forward thrust on n°4 engine at the time the pilot flying was coming out of reverse thrust on engines n°1, 2 and 3 during the landing roll, and subsequent failure of the crew to recognize the asymmetric power condition. Contributing were failure of the crew to monitor the engines, and failure to follow specified procedures during the landing.

Crash of a Boeing 727-235 in New Orleans: 153 killed

Date & Time: Jul 9, 1982 at 1608 LT
Type of aircraft:
Operator:
Registration:
N4737
Flight Phase:
Survivors:
No
Site:
Schedule:
Miami - New Orleans - Las Vegas - San Francisco - San Diego
MSN:
19457
YOM:
1968
Flight number:
PA759
Crew on board:
7
Crew fatalities:
Pax on board:
138
Pax fatalities:
Other fatalities:
Total fatalities:
153
Captain / Total flying hours:
11727
Captain / Total hours on type:
10595.00
Copilot / Total flying hours:
6127
Copilot / Total hours on type:
3914
Aircraft flight hours:
39253
Aircraft flight cycles:
35643
Circumstances:
Pan Am Flight 759 was a scheduled flight from Miami (MIA) to Las Vegas (LAS), with an en route stop at New Or1eans (MSY). At 15:58:48 Boeing 727 "Clipper Defiance" taxied from its gate at the New Orleans International Airport. Before leaving the gate, the flightcrew had received ATIS message Foxtrot which read in part "....time one eight five five Zulu, weather, two thousand five hundred scattered, two five thousand thin broken, visibility six miles in haze, temperature niner zero, wind two four zero at two, winds are calm altimeter three zero zero one...". The flightcrew requested runway 10 for the takeoff and ground control cleared the flight to taxi to runway 10. At 15:59:03, the first officer requested a wind check. Winds were 040 degrees at 8 knots. At 16:02:34, while Flight 759 was taxiing to runway 10, the crew heard a transmission from ground control, advising another airplane of low level wind shear alerts in the northeast quadrants of the airport. At 16:03:33, the first officer requested another wind check. Ground control replied, "Wind now zero seven zero degrees at one seven... peak gusts two three, and we have low level wind shear alerts all quadrants, appears to be a frontal passing overhead right now, we're right in the middle of everything." The captain then advised the first officer to "...let your airspeed build up on takeoff..." and said that they would turn off the air conditioning packs for the takeoff, which would enable them to increase the EPR's on engines Nos. 1 and 3 to 1.92. The flightcrew completed the takeoff and departure briefings and turned onto the active runway for takeoff. At l6:06:22, Flight 759 informed the tower that it was ready for takeoff. The local controller cleared the flight for takeoff, and the first officer acknowledged the clearance. About 16:07:57, the Boeing 727 began its takeoff. According to witnesses, the airplane lifted off about 7,000 feet down runway 10, climbed in a wings-level attitude, reached an altitude of about 100 feet to 150 feet above the ground (AGL), and then began to descend towards trees. The airplane crashed into a residential area and was destroyed during the impact, explosion, and subsequent ground fire. Eight persons on the ground were killed.
Probable cause:
The airplane's encounter during the lift-off and initial climb phase of flight with a micro-burst induced windshear which imposed a downdraft and a decreasing headwind, the effects of which the pilot would have had difficulty recognizing and reacting to in time for the airplane's descent to be arrested before its impact with trees. Contributing to the accident was the limited capability of current ground based low level windshear detection technology to provide definitive guidance for controllers and pilots for use in avoiding low level wind shear encounters.
Final Report:

Crash of a Boeing 727-21 in San José

Date & Time: Sep 3, 1980 at 1437 LT
Type of aircraft:
Operator:
Registration:
N327PA
Survivors:
Yes
Schedule:
Miami - San José
MSN:
19036
YOM:
1966
Flight number:
PA421
Country:
Crew on board:
6
Crew fatalities:
Pax on board:
67
Pax fatalities:
Other fatalities:
Total fatalities:
0
Circumstances:
On final approach to San José-Juan Santamaría Airport, the crew encountered poor weather conditions. In limited visibility due to rain falls, the airplane descended below the glide until the right main gear struck the ground 15 meters short of runway 07 threshold. On impact, the landing gear was torn off. Out of control, the airplane struck the ground, lost its undercarriage then slid on several dozen meters before coming to rest. All 73 occupants escaped uninjured while the aircraft christened 'Clipper Meteor' was damaged beyond repair.
Final Report:

Crash of a Boeing 747-121 in Tenerife: 335 killed

Date & Time: Mar 27, 1977 at 1706 LT
Type of aircraft:
Operator:
Registration:
N736PA
Flight Phase:
Survivors:
Yes
Schedule:
Los Angeles – New York – Las Palmas
MSN:
19643
YOM:
1969
Flight number:
PA1736
Country:
Region:
Crew on board:
16
Crew fatalities:
Pax on board:
380
Pax fatalities:
Other fatalities:
Total fatalities:
335
Captain / Total flying hours:
21043
Captain / Total hours on type:
564.00
Copilot / Total flying hours:
10800
Copilot / Total hours on type:
2796
Aircraft flight hours:
25725
Aircraft flight cycles:
7195
Circumstances:
The KLM Boeing 747, registration PH-BUF, took off from Schipol Airport (Amsterdam) at 0900 hours on 27 March 1977, en route to Las Palmas de Gran Canaria. This flight was part of the Charter Series KL4805/4806 Amsterdam-Las Palmas (Canary Islands) - Amsterdam operated by KLM on behalf of the Holland International Travel Group (H.I.N.T.), Rijswijk-Z.H. The Boeing 747 registration N736PA, flight number 1736, left Los Angeles International Airport, California, United States, on 26 March 1977, local date, at 0129Z hours, arriving at John F. Kennedy International Airport at 0617Z hours. After the aeroplane was refuelled and a crew change effected, it took off for Las Palmas de Gran Canaria (Spain) at 0742Z. While the aeroplanes were en route to Las Palmas, a bomb exploded in the airport passenger terminal. On account of this incident and of a warning regarding a possible second bomb, the airport was closed. Therefore, KLM 4805 was diverted to Los Rodeos (Tenerife) Airport, arriving at 1338Z on 27 March 1977. For the same reason, PAA1736 proceeded to the same airport, which was its alternate, landing at 1415. At first the KLM passengers were not allowed to leave the aeroplane, but after about twenty minutes they were all transported to the terminal building by bus. On alighting from the bus, they received cards identifying them as passengers in transit on Flight KL 4805. Later, all the passengers boarded KLM 4805 expect the H.I.N.T. Company guide, who remained in Tenerife. When Las Palmas Airport was opened to traffic once more, the PAA 1736 crew prepared to proceed to Las Palmas, which was the flight's planned destination. When they attempted to taxi on the taxiway leading to runway 12, where they had been parked with four other aeroplanes on account of the congestion caused by the number of flights diverted to Tenerife, they discovered that it was blocked by KLM Boeing 747, Flight 4805, which was located between PAA 1736 and the entrance to the active runway. The first officer and the flight engineer left the aeroplane and measured the clearance left by the KLM aircraft, reaching the conclusion that it was insufficient to allow PAA 1736 to pass by, obliging them to writ until the former had started to taxi. The passengers of PAA 1736 did not leave the aeroplane during the whole time that it remained in the airport. KLM 4805 called the tower at 1656 requesting permission to taxi. It was authorized to do so and at 1658 requested to backtrack on runway 12 for take-off on runway 30. The tower controller first cleared the KLM flight to taxi to the holding position for runway 30 by taxiing down the main runway and leaving it by the (third) taxiway to its left. KLM 4805 acknowledged receipt of this message from the tower, stating that it was at that moment taxiing on the runway, which it would leave by the first taxiway in order to proceed to the approach end of runway 30. The tower controller immediately issued an amended clearance, instructing it to continue to taxi to the end of the runway, where it should proceed to backtrack. The KLM flight confirmed that it had received the message, that it would backtrack, and that it was taxiing down tile main runway. The tower signalled its approval, whereupon KLM 4805 immediately asked the tower again if what they had asked it to do was to turn left on taxiway one. The tower replied in the negative and repeated that it should continue on to the end of the runway and there backtrack. Finally, at 1659, KLM 4805 replied, "O.K., sir." At 1702, the PAA aeroplane called the tower to request confirmation that it should taxi down the runway. The tower controller confirmed this, also adding that they should leave the runway by the third taxiway to their left. At 1703:00, in reply to the tower controller's query to KLM 4805 as to how many runway exits they had passed, the latter confirmed that at that moment they were passing by taxiway C4. The tower controller told KLM 4805, "O.K., at the end of the runway make one eighty and report ready for ATC clearance ." In response to a query from KLM 4805, the tower controller advised both aeroplanes - KLM 4805 and PAA 1736 - that the runway centre line lights were out of service. The controller also reiterated to PAA 1736 that they were to leave the main runway via the third taxiway to their left and that they should report leaving the runway. At the times indicated, the following conversations took place between the tower and the KLM 4805 and PAA 1736 aeroplanes. Times taken from KLM CVR.
1705:44.6 KLM 4805: The KLM four eight zero five is now ready for take-off and we are waiting for our ATC clearance. (1705:50.77).
1705:53.41 Tower: KLM eight seven zero five you are cleared to the Papa Beacon, climb to and maintain flight level nine zero, right turn after take-off, proceed with heading four zero until intercepting the three two five radial from Las Palmas VOR. (1706 :08.09).
1706:09.61 KLM 4805: Ah - Roger, sir, we are cleared to the Papa Beacon, flight level nine zero until intercepting the three two five. We are now (at take-off). (1706:17.79).
1706:18.19 Tower : O.K..... Stand by for take-off, I will call you. (1706: 21.79).
Note: A squeal starts at: 1706:19.39 The squeal ends at: 1706:22.06
1706:21.92 PAA 1736: Clipper one seven three six. (1706 : 23.39).
1706:25.47 Tower: Ah - Papa Alpha one seven three six report the runway clear. (1706: 28.89).
1706:29.59 PAA 1736: O.K., will report when we're clear. (1706:30.69).
1706:31.69 Tower: Thank you.
Subsequently, KLM 4805, which had released its brakes to start take-off run 20 seconds before this communication took place, collided with the PAA aeroplane. The control tower received no further communications from PAA 1736, nor from KLM 4805. There were no eyewitnesses to the collision. All 248 occupants on board the KLM 747 were killed. Among the 396 people on board the Pan Am 747, 335 were killed (among them nine crew members) and 61 others were injured.
Probable cause:
The KLM aircraft had taken off without take-off clearance, in the absolute conviction that this clearance had been obtained, which was the result of a misunderstanding between the tower and the KLM aircraft. This misunderstanding had arisen from the mutual use of usual terminology which, however, gave rise to misinterpretation. In combination with a number of other coinciding circumstances, the premature take-off of the KLM aircraft resulted in a collision with the Pan Am aircraft, because the latter was still on the runway since it had missed the correct intersection.
Final Report:

Crash of a Boeing 707-321C near Denpasar: 107 killed

Date & Time: Apr 22, 1974 at 2226 LT
Type of aircraft:
Operator:
Registration:
N446PA
Survivors:
No
Site:
Schedule:
Hong Kong - Denpasar - Sydney - Suva - Honolulu - Los Angeles
MSN:
19268/544
YOM:
1966
Flight number:
PA812
Country:
Region:
Crew on board:
11
Crew fatalities:
Pax on board:
96
Pax fatalities:
Other fatalities:
Total fatalities:
107
Captain / Total flying hours:
18247
Captain / Total hours on type:
7192.00
Copilot / Total flying hours:
6312
Copilot / Total hours on type:
4776
Aircraft flight hours:
27943
Aircraft flight cycles:
9123
Circumstances:
Following an uneventful flight from Hong Kong-Kai Tak, the crew started the descent to Denpasa-Ngurah Rai Airport by night and limited visibility. While descending to runway 09 at an altitude of 4,000 feet, the airplane initiated a turn to 263° when it struck the slope of Mt Masehe located about 68 km from the airport. The wreckage was found few hours later. The aircraft was totally destroyed upon impact and all 107 occupants have been killed.
Probable cause:
The premature execution of a right-hand turn to join the 263 degrees outbound track which was based on the indication given by only one of the ADF's while the other one was still in steady condition.
Final Report:

Crash of a Boeing 707-321B in Pago Pago: 97 killed

Date & Time: Jan 30, 1974 at 2341 LT
Type of aircraft:
Operator:
Registration:
N454PA
Survivors:
Yes
Schedule:
Auckland - Pago Pago - Honolulu - Los Angeles
MSN:
19376/661
YOM:
1967
Flight number:
PA806
Region:
Crew on board:
10
Crew fatalities:
Pax on board:
91
Pax fatalities:
Other fatalities:
Total fatalities:
97
Captain / Total flying hours:
17414
Captain / Total hours on type:
7416.00
Copilot / Total flying hours:
5107
Copilot / Total hours on type:
5107
Aircraft flight hours:
21625
Circumstances:
On January 30, 1974, Pan Am Flight 806, Boeing 707-321B 'Clipper Radiant' operated as a scheduled flight from Auckland, New Zealand, to Los Angeles, California. En route stops included Pago Pago, American Samoa, and Honolulu, Hawaii. Flight 806 departed Auckland at 2014. It was cleared to Pago Pago on an IFR flight plan. At 2311, Flight 806 contacted Pago Pago Approach Control and reported its position 160 miles south of the Pago Pago airport. Approach control responded, "Clipper eight zero six, roger, and Pago weather, estimated ceiling one thousand six hundred broken, four thousand broken, the visibility - correction, one thousand overcast. The visibility one zero, light rain shower, temperature seven eight, wind three five zero degrees, one five, and altimeter's two nine eight five." At 2313, Pago Pago Approach Control cleared the flight to the Pago Pago VORTAC. Flight 806 reported leaving FL330 three minutes later and leaving FL200 at 2324. Pago Pago Approach Control cleared the flight at 2324: "Clipper eight zero six, you're cleared-for the ILS DME runway five approach - via the two zero mile arc south-southwest. Report the arc, and leaving five thousand." At 2333, the flight requested the direction and velocity of the Pago Pago winds and was told that they were 360 degrees variable from 020 degrees at 10 to 15 knots. At 2334, the flight reported out of 5,500 feet and that they had intercepted the 226 degree radial of the Pago Pago VOR. The approach controller responded, "Eight oh six, right. Understand inbound on the localizer. Report about three out. No other reported traffic. Winds zero one zero degrees at one five gusting two zero." At 2338, approach control said, "Clipper eight oh six, appears that we've had power failure at the airport. " The first officer replied, "Eight oh six, we're still getting your VOR, the ILS and the lights are showing." Approach control then asked, "See the runway lights?" The flight responded, "That's Charlie." The approach controller then said, " ...we have a bad rain shower here. I can't see them from my position here." "We're five DME now and they still look bright," the first officer responded. Approach Control replied, "´kay, no other reported traffic. The wind is zero three zero degrees at two zero, gusting two five. Advise clear of the runway." At 23:39:41, the flight replied, "Eight zero six, wilco." This was the last radio transmission from the flight. On the flight deck the windshield wipers were turned on and the flaps were set at the 50° position, which completed the checklists for landing. At 23:40:22, the first officer stated, "You're a little high." The radio altimeter warning tone then sounded twice and the first officer said "You're at minimums." He reported the field in sight and said that they were at 140 kts. At 23:40:42, the aircraft crashed into trees at an elevation of 113 feet, and about 3,865 feet short of the runway threshold. The first impact with the ground was about 236 feet farther along the crash path. The aircraft continued through the jungle vegetation, struck a 3-foot-high lava rock wall, and stopped about 3,090 feet from the runway threshold. Of the 101 occupants of the aircraft, 9 passengers and 1 crew member survived the crash and fire. One passenger died the next day; the crew member and three passengers died 3 days after the accident. One passenger died of his injuries 9 days after the accident. Thus only four passengers survived the crash.
Probable cause:
The flight crew's late recognition, and failure to correct in a timely manner, an excessive descent rate which developed as a result of the aircraft's penetration through destabilizing wind changes. The winds consisted of horizontal and vertical components produced by a heavy rainstorm and influenced by uneven terrain close to the aircraft's approach path. The captain's recognition was hampered by restricted visibility, the illusory effects of a "black hole" approach, inadequate monitoring of flight instruments, and the failure of the crew to call out descent rate during the last 15 seconds of flight.
Final Report:

Ground explosion of a Boeing 707-321B in Rome: 33 killed

Date & Time: Dec 17, 1973 at 1300 LT
Type of aircraft:
Operator:
Registration:
N407PA
Flight Phase:
Survivors:
Yes
Schedule:
New York - London - Rome - Beirut - Tehran
MSN:
18838
YOM:
1965
Flight number:
PA110
Country:
Region:
Crew on board:
11
Crew fatalities:
Pax on board:
166
Pax fatalities:
Other fatalities:
Total fatalities:
33
Circumstances:
While parked at Rome-Fiumicino-Leonardo da Vinci Airport and ready for departure, the aircraft was attacked by six members from a Palestinian terrorist group. Shots burst with police forces and several grenades detonated, causing the aircraft to catch fire. 15 occupants were seriously injured while 129 others were unhurt. Unfortunately, 33 passengers were killed during this terrorist attack.
Probable cause:
Terrorist attack.
Final Report:

Crash of a Boeing 707-321C in Boston: 3 killed

Date & Time: Nov 3, 1973 at 0939 LT
Type of aircraft:
Operator:
Registration:
N458PA
Flight Type:
Survivors:
No
Schedule:
New York - Glasgow - Frankfurt
MSN:
19368/640
YOM:
1967
Flight number:
PA160
Crew on board:
3
Crew fatalities:
Pax on board:
0
Pax fatalities:
Other fatalities:
Total fatalities:
3
Captain / Total flying hours:
16477
Captain / Total hours on type:
5824.00
Copilot / Total flying hours:
3843
Copilot / Total hours on type:
3843
Aircraft flight hours:
24537
Circumstances:
Pan American World Airways Clipper Flight 160 was a scheduled cargo flight from New York-JFK to Frankfurt (FRA), Germany, with a scheduled stop at Prestwick (PIK), Scotland. At 08:25 the flight departed JFK. The aircraft was carrying 52912 lb (24000 kg) of cargo, 15,360 lb (6967 kg) of which were chemicals. After departure, Clipper 160 was vectored on course while climbing to FL330. At 08:44, Clipper 160's clearance was amended, and it was instructed to maintain FL310 as a final cruising altitude. Clipper 160 reported level at FL310 at 08:50. As the flight approached Sherbrooke VORTAC 100 miles east of Montreal, Canada, at about 09:04, it advised Pan American Operations (PANOP) in New York that smoke had accumulated in the "lower 41" electrical compartment, and that the flight was diverting to Boston. At 09:08, Clipper 160 advised Montreal Center that they were level at FL310 and wanted to return to JFK. Montreal Center cleared Clipper 160 for a right turn to a heading of 180 degrees. At 09:10, Clipper 160 advised PANOP that it was returning to New York and that the smoke seemed to be "getting a little thicker in here." At 09:11, the crew advised PANOP that they were now going to Boston and that "this smoke is getting too thick." They also requested that emergency equipment be available when they arrived at Boston. During this conversation, the comment was made that the "cockpit's full back there." During its return to Boston, the flight was given preferential air traffic control treatment, although it had not declared an emergency. After issuing appropriate descent clearances en route so that fuel could be burned off more rapidly at lower altitudes, at 09:26:30 Boston Center advised Boston Arrival Radar that the flight was at 2,000 feet. At 09:29, Clipper 160 asked Boston Center for the flight's distance from Boston, and added, "The DME's don't seem to be working." The Center answered, "You're passing abeam, Pease Air Force Base, right now, sir, and you're about 40 to 45 miles to the northwest of Boston." The first communication between Clipper 160 and the arrival radar controller was at 09:31:21. The flight was cleared "direct Boston, maintain 2,000." The controller asked if the flight was declaring an emergency; the reply was "negative on the emergency, and may we have runway 33 left?" The controller approved the request, and the flight proceeded to Boston as cleared. At approximately the same time, the captain instructed the crew to "shut down everything you don't need." At 09:34:20, the controller asked, "Clipper 160, what do you show for a compass heading right now?" Clipper 160 answered, "Compass heading at this time is 205." The controller then asked, "will you accept a vector for a visual approach to a 5-mile final for runway 33 left, or do you want to be extended out further?" The crew replied, "Negative, we want to get it on the ground as soon as possible." At 09:35:46, the controller stated, "Clipper 160, advise anytime you have the airport in sight." Clipper 160 did not reply. At 09:37:04, the arrival controller made the following transmission: "Clipper 160, this is Boston approach control. If you read, squawk ident on any transponder. I see your transponder just became inoperative. Continue inbound now for runway 33 left, you're No. 1. There is a Lufthansa 747 on a 3-mile final for runway 27, the spacing is good. Remain on this frequency, Clipper 160." There was no reply from the flight. With flaps and spoilers had been extended for speed reduction, the airplane approached runway 33L. The yaw damper was rendered inoperative by the uncoordinated execution of emergency procedures earlier. This made the 707 extremely difficult to control at low speeds. Control was lost and the airplane struck the ground nose down about 262 feet from the right edge of the approach end of runway 33.Pan American World Airways Clipper Flight 160 was a scheduled cargo flight from New York-JFK to Frankfurt (FRA), Germany, with a scheduled stop at Prestwick (PIK), Scotland. At 08:25 the flight departed JFK. The aircraft was carrying 52912 lb (24000 kg) of cargo, 15,360 lb (6967 kg) of which were chemicals. After departure, Clipper 160 was vectored on course while climbing to FL330. At 08:44, Clipper 160's clearance was amended, and it was instructed to maintain FL310 as a final cruising altitude. Clipper 160 reported level at FL310 at 08:50. As the flight approached Sherbrooke VORTAC 100 miles east of Montreal, Canada, at about 09:04, it advised Pan American Operations (PANOP) in New York that smoke had accumulated in the "lower 41" electrical compartment, and that the flight was diverting to Boston. At 09:08, Clipper 160 advised Montreal Center that they were level at FL310 and wanted to return to JFK. Montreal Center cleared Clipper 160 for a right turn to a heading of 180 degrees. At 09:10, Clipper 160 advised PANOP that it was returning to New York and that the smoke seemed to be "getting a little thicker in here." At 09:11, the crew advised PANOP that they were now going to Boston and that "this smoke is getting too thick." They also requested that emergency equipment be available when they arrived at Boston. During this conversation, the comment was made that the "cockpit's full back there." During its return to Boston, the flight was given preferential air traffic control treatment, although it had not declared an emergency. After issuing appropriate descent clearances en route so that fuel could be burned off more rapidly at lower altitudes, at 09:26:30 Boston Center advised Boston Arrival Radar that the flight was at 2,000 feet. At 09:29, Clipper 160 asked Boston Center for the flight's distance from Boston, and added, "The DME's don't seem to be working." The Center answered, "You're passing abeam, Pease Air Force Base, right now, sir, and you're about 40 to 45 miles to the northwest of Boston." The first communication between Clipper 160 and the arrival radar controller was at 09:31:21. The flight was cleared "direct Boston, maintain 2,000." The controller asked if the flight was declaring an emergency; the reply was "negative on the emergency, and may we have runway 33 left?" The controller approved the request, and the flight proceeded to Boston as cleared. At approximately the same time, the captain instructed the crew to "shut down everything you don't need." At 09:34:20, the controller asked, "Clipper 160, what do you show for a compass heading right now?" Clipper 160 answered, "Compass heading at this time is 205." The controller then asked, "will you accept a vector for a visual approach to a 5-mile final for runway 33 left, or do you want to be extended out further?" The crew replied, "Negative, we want to get it on the ground as soon as possible." At 09:35:46, the controller stated, "Clipper 160, advise anytime you have the airport in sight." Clipper 160 did not reply. At 09:37:04, the arrival controller made the following transmission: "Clipper 160, this is Boston approach control. If you read, squawk ident on any transponder. I see your transponder just became inoperative. Continue inbound now for runway 33 left, you're No. 1. There is a Lufthansa 747 on a 3-mile final for runway 27, the spacing is good. Remain on this frequency, Clipper 160." There was no reply from the flight. With flaps and spoilers had been extended for speed reduction, the airplane approached runway 33L. The yaw damper was rendered inoperative by the uncoordinated execution of emergency procedures earlier. This made the 707 extremely difficult to control at low speeds. Control was lost and the airplane struck the ground nose down about 262 feet from the right edge of the approach end of runway 33. The aircraft was totally destroyed and all three crew members were killed.
Probable cause:
The presence of smoke in the cockpit which was continuously generated and uncontrollable. The smoke led to an emergency situation that culminated in loss of control of the aircraft during final approach, when the crew in uncoordinated action deactivated the yaw damper in conjunction with incompatible positioning of flight spoilers and wing flaps. The NTSB further determines that the dense smoke in the cockpit seriously impaired the flight crew's vision and ability to function effectively during the emergency. Although the source of the smoke could not be established conclusively, the NTSB believes that the spontaneous chemical reaction between leaking acid, improperly packaged and stowed, and the improper sawdust packing surrounding the acid's package initiated the accident sequence. A contributing factor was the general lack of compliance with existing regulations governing the transportation of hazardous materials which resulted from the complexity of the regulations, the industry wide lack of familiarity with the regulations and the working level, the over-lapping jurisdictions, and the inadequacy of government surveillance.
Final Report: