Vintage: The crash of South African Airways Flight 295, Helderberg, November 1987
South African Airways Flight 295 was a commercial flight from Chiang Kai-shek International Airport, Taipei, Taiwan to Jan Smuts International Airport, Johannesburg, South Africa, with a stopover in Plaisance Airport, Plaine Magnien, Mauritius. On 28 November 1987, the aircraft serving the flight, a Boeing 747 Combi named Helderberg, experienced a catastrophic in-flight fire in the cargo area, broke-up in mid-air, and crashed into the Indian Ocean east of Mauritius, killing all 159 people on board. An extensive salvage operation was mounted to try to recover the black box recorders, one of which was recovered from a depth of 4 900 metres (16 100ft). The official inquiry, headed by Judge Cecil Margo, was unable to determine the cause of the fire. This lack of a conclusion led to conspiracy theories being advanced in the years following the accident.
The aircraft involved, a Boeing 747-244BM Combi registered ZS-SAS and named Helderberg, made its first flight on 12 November 1980 and was delivered to South African Airways on 24 November 1980.
The Boeing 747-200B Combi model permits the mixing of passengers and cargo on the main deck according to load factors on any given route and Class B cargo compartment regulations. Flight 295 had 140 passengers and six pallets of cargo on the main deck. The master waybills stated that 47 000 kilograms (104 000 lb) of baggage and cargo were loaded on the aircraft. A Taiwanese customs official performed a surprise inspection of some of the cargo; he did not find any cargo that could be characterised as suspicious.
The aircraft took off on 27 November 1987 from Taipei Chiang Kai Shek International Airport, on a flight to Johannesburg via Mauritius.
The flight crew consisted of 49-year-old captain Dawie Uys, with 13 843 hours' experience; 36-year-old first officer David Attwell and 37-year-old relief first officer Geoffrey Birchall, with 7 362 and 8 749 hours' experience respectively; and 45-year-old flight engineer, Giuseppe "Joe" Bellagarda and 34-year-old relief flight engineer, Alan Daniel, with 7 804 hours and 1 595 hours of experience respectively.
Thirty-four minutes after departure, the crew contacted Hong Kong air traffic control to obtain clearance from waypoint ELATO (22°19′N 117°30′E) to ISBAN. A position report was made over ELATO at 15:03:25, followed by waypoints SUNEK at 15:53:52, ADMARK at 16:09:54 and SUKAR (12°22′N 110°54′E) at 16:34:47. The aircraft made a routine report to the South African Airways base at Johannesburg at 15:55:18.
At some point during the flight, believed to be during the beginning of its landing approach, a fire developed in the cargo section on the main deck which was probably not extinguished before impact. The 'smoke evacuation' checklist calls for the aircraft to be depressurised and for two of the cabin doors to be opened. No evidence exists that the checklist was followed or that the doors were opened. A crew member might have gone into the cargo hold to try to fight the fire. A charred fire extinguisher was later recovered from the wreckage on which investigators found molten metal.
The fire started to destroy the aircraft's important electrical systems, resulting in loss of communication and control of the aircraft. At exactly 00h07 UTC (4h07 local time), the aircraft broke apart in mid-air, the tail section breaking off first, due to the fire beginning to burn the structure of the aircraft, and crashed into the Indian Ocean, about 134 nautical miles (154 miles) from the Airport.
After communication with Flight 295 was lost for 36 minutes, at 00h44 (4h44 local time), Air Traffic Control at Mauritius formally declared an emergency.
When the Helderberg last informed Mauritian air traffic control of its position, its report was incorrectly understood to be relative to the airport rather than its next waypoint, which caused the subsequent search to be concentrated too close to Mauritius. The United States Navy sent aircraft from Diego Garcia, which were used to conduct immediate search and rescue operations in conjunction with the French Navy. By the time the first surface debris was located 12 hours after impact, it had drifted considerably from the impact location. Oil slicks and eight bodies showing signs of extreme trauma appeared in the water. All 140 passengers and 19 crew on the manifest were killed.
South Africa sent a total of six naval and civilian vessels to the search area.
After recovery of the wreckage from 4 000 m (13 000ft) below the surface of the ocean, the aircraft's fuselage and cabin interior were partly reassembled in one of SAA's hangars at Jan Smuts Airport where it was examined and finally opened for viewing to the airline's staff and selected members of the public.
Rennie Van Zyl, the head Southern African investigator, examined three wristwatches from the baggage recovered from the surface; two of the watches were still running according to Taiwan time. Van Zyl deduced the approximate time of impact from the stopped watch. The aircraft crashed at 00:07:00, around three minutes after the last communication with air traffic control. Immediately after the crash, the press and public opinion suspected that terrorism brought down the Helderberg. Experts searched for indicators of an explosion on the initial pieces of wreckage discovered, such as surface pitting, impact cavities and spatter cavities caused by white hot fragments from explosive devices that strike and melt metal alloys found in aircraft structures. Experts found none of this evidence. The investigators drew blood samples from two of the recovered bodies and found that the bodies had soot in their tracheae, indicating that they had died from smoke inhalation before the aircraft had crashed.
The South Africans mounted an underwater search, named Operation Resolve, to try to locate the wreckage. The underwater locator beacons (ULBs) attached to the flight recorders were not designed for deep ocean use; nevertheless, a two-month-long sonar search for them was carried out before the effort was abandoned on 8 January 1988 when the ULBs were known to have stopped transmitting (at the time a ULB had to generate sonic pulses for 30 days). Steadfast Oceaneering, a specialist deep ocean recovery company in the US, was contracted at great expense to find the site and recover the flight recorders. The search area is described as being comparable in size to that of the RMS Titanic, with the water at 5 000 metres (16 000ft) being considerably deeper than any previously successful salvage operation. The wreckage was found within two days of Steadfast Oceaneering commencing its search.
Three debris fields were found: 19°10′30″S 59°38′0″E, 19°9′53″S 59°38′32″E and 19°9′15″S 59°37′25″E. These locations were spread 1,5km (0,93mi), 2,3km (1,4mi) and 2,5km (1,6mi) apart, indicating that the aircraft broke up in mid-air (it was suggested that the tail separated first). On 6 January 1989, the cockpit voice recorder (CVR) was salvaged successfully from a record depth of 4 900 metres (16 100ft) by the remotely operated vehicle (ROV) Gemini but the flight data recorder was never found.
Van Zyl took the voice recorder to the United States National Transportation Safety Board (NTSB) in Washington, DC, to show his goodwill and to ensure neutral observers. Van Zyl believes that if he kept the CVR in South Africa he could have been accused of covering up the truth. At the NTSB, van Zyl felt frustration that the degraded (but still functional) CVR, which had been in the deep ocean for fourteen months, did not initially yield any useful information. Around 28 minutes into the recording the CVR indicated that the fire alarm sounded. Fourteen seconds after the fire alarm, the circuit breakers began to pop. Investigators believe that around 80 circuit breakers failed. The CVR cable failed 81 seconds after the alarm. The recording revealed the extent of the fire.
Van Zyl discovered that the front-right pallet was the seat of the fire. The manifest said that pallet mostly comprised computers in polystyrene packaging. The investigators said that the localised fire likely came in contact with the packaging and produced gases that accumulated near the ceiling. They also said that gases ignited into a flash fire that affected the entire cargo hold. The cargo fire of Flight 295 did not burn lower than one metre above the cargo floor. The walls and ceiling of the cargo hold received severe fire damage. Van Zyl ended his investigation without discovering why the fire started.
The official report noted the presence of the computer equipment, and suggested that a possible cause could have been the lithium batteries contained in the computers exploding or spontaneously combusting, although this was not given as a conclusive cause of the fire.
An official commission of inquiry was chaired by Judge Cecil Margo, with co-operation from the NTSB and the aircraft manufacturer, Boeing.
The official report determined that while the Helderberg was over the Indian Ocean, a fire had occurred in the cargo hold of the main deck, originating in the front right-hand cargo pallet. Aircraft parts recovered from the ocean floor showed fire damage sustained in temperatures over 300°C (570°F); tests showed that temperatures of 600°C (1 100°F) would have been required to melt a carbon-fibre tennis racket recovered from the crash site. The reason for the aircraft's loss was not identified beyond doubt but there were two possibilities detailed in the official report: firstly, that the crew became incapacitated due to smoke penetrating into the cockpit and secondly, that the fire weakened the structure so that the tail separated, leading to impact with the ocean. The commission concluded that it was not possible to apportion blame to any one individual for the fire, removing any terrorism concerns. The manufacturer is quoted in the report as having "contested" any scenario that involved a break-up of the aircraft, hence the commission went no further than simply mentioning the two possible scenarios in its final report, as incidental to the primary cause of the accident.
The commission determined that inadequate fire detection and suppression facilities in the class B cargo bays (the type used aboard the 747-200 Combi) were the primary cause of the aircraft's loss. The accident alerted aviation authorities worldwide to the fact that the regulations regarding class B cargo bays had lagged far behind the growth in their capacity. The exact source of ignition was never determined, but the report concluded that there was sufficient evidence to confirm that the fire had burned for some considerable time and that it might have caused structural damage.
The crash was the first fire incident on the 747 Combi and one of few fires on widebody aircraft. Fred Bereswill, the investigator from Boeing, characterised the Flight 295 fire as significant for this reason. Barry Strauch of the NTSB visited Boeing's headquarters to inquire about the Combi's design. Boeing's fire test in the Combi models did not accurately match the conditions of the Helderberg's cargo hold; in accordance with federal US rules, the Boeing test involved setting a bale of tobacco leaves ablaze. The fire stayed within the cargo hold. The air in the passenger cabin was designed to have a marginally higher pressure than cargo area hold, so if a crew member opened the door to the cargo hold, the air from the passenger cabin would flow into the cargo hold, stopping any smoke or gases from exiting through the door.
Investigators devised a new test involving a cargo hold with conditions similar to the conditions of Flight 295; the plastic covers and extra pallets provided fuel for the fire, which would spread quickly before generating enough smoke to activate smoke alarms. The hotter flame achieved in the new test heated the air in the cargo hold. This heated air had a higher pressure than normal and overcame the pressure differential between the cargo hold and the passenger cabin. When the door between the passenger and cargo holds was open, smoke and gases therefore flowed into the passenger cabin.
The test as well as evidence from the accident site proved to the investigators that the 747 Combi's use of a class B cargo hold did not provide enough fire protection to the passengers. The FAA confirmed this finding in 1993 with its own series of tests.
After the accident, South African Airways discontinued use of the Combi and the Federal Aviation Administration introduced new regulations in 1993 specifying that manual fire fighting must not be the primary means of fire suppression in the cargo compartment of the main deck. Complying with these new standards required weight increases, which made the 747 Combi no longer viable. Nevertheless, the Combi remained in the 747 product line up until 2002, when the last 747-400 Combi was delivered to KLM.