Pan Am Flight 708 (lost flight recorders of fatal cargo aircraft crash; 1966)
On 15th November 1966, cargo aircraft Pan Am Flight 708 was on-route from Frankfurt Airport to Berlin Tegel when it crashed near Dallgow, East Germany, killing all three crew members on-board. The crash's cause has yet to be officially explained, primarily due to a lack of key information surrounding the flight. This was caused by the Soviet Union controversially deciding not only to forbid US investigators access to the crash site, but also providing less than half the wreckage to West Berlin for analysis. Among missing components include the flight data and cockpit voice recorders.
Pan Am Flight 708, consisting of a Boeing 727, took off at around 01:04 am GMT on 15th November from Frankfurt Airport, West Germany. A routine mail flight, Flight 708's typical destination of Tempelhof Airport had been undergoing runway resurfacing, and so the new destination became Berlin Tegel in East Germany. The flight before, it had transported mail from Tegel to Frankfurt. Its crew consisted of captain Walter T. Reavis; co-pilot Raymond B. Foppe; and flight engineer John W. Charlton. All were vastly experienced, and later pathological and toxicological analysis indicated none were incapacitated. Additionally, a fellow Pan-American pilot had been speaking to captain Reavis prior to departure, noting nothing out of the ordinary with his behaviour. The flight was expected to reach its destination at around 02:55 am.
By 01:33:50 am, the flight was cleared for a descent by Berlin Control. This occurred during snowy weather, and with a maximum visibility of 2.6 kilometres. At around 01:41:30 am, the airport's flight controller informed 708's crew that their plane was now approximately 6.5 miles from the airport's outer marker, clearing the flight to land at ILS (Instrument Landing System) runway eight on the right approach. Eight seconds later, the crew acknowledged this, stating "'ger zero six zero clear ILS seven oh eight." Ultimately, this proved to be the final communication from 708, and seconds later, it disappeared from radar.The flight controller was unable to resume contact with 708 despite several attempts. It took ten hours before the Soviet Union's Berlin Air Safety Center representative informed that the flight had crashed 9.7 miles from Tegel, not far from Dallgow. The subsequent impact caused the wreckage to erupt into flames. None of the three crew members survived the crash.
Following the accident, Soviet officials began assessing the accident. However, no Western officials, including those from America's National Transportation Safety Board (NTSB), were granted access to the wreck site. Crucially, the Soviet Union was not yet a member of the International Civil Aviation Organization (ICAO), which encouraged international cooperation and enabled official observers to join crash investigations to mutually improve safety. Two days following the accident, the Soviet Union agreed to transfer the bodies, surviving mailbags, and wreckage to the NTSB at the Staaken checkpoint.The bodies therefore underwent the aforementioned pathological and toxicological analysis, wiping out the theory the crew was incapacitated. But, in a move provoking intense debate as of the present day, the NTSB discovered that Soviet officials had handed over less than 50% of the wreckage.
The final NTSB report indicated that twelve vital components were not included as part of the transfer. These included the flight data recorder; the cockpit voice recorder; the stabiliser jackscrew, feel computer and box beam of the vertical fin and horizontal stabilisers; key components from the No. 1 engine; the majority of the flight control systems; cockpit instrumentation devices such as the navigation and communication equipment and the flight engineer's panel; both the pilot and co-pilot's seats; the cockpit pedestal; the key landing gears and wheels; and the support beam for the left main landing gear. The Soviet Union's decision to withhold key components was widely criticised; however, it should be noted that Western countries like the United Kingdom were accused of withholding components crucial for the Soviet Union's previous crash investigations, such as a Jak-28P crash on 6th April 1966. NTSB representatives believed that the withheld contents were of little strategic value for the Soviet Union, as the American equipment had been in long-term use.
The NTSB's investigation was therefore considerably hampered. Aside from being unable to analyse the missing components, being forbidden from accessing the crash site meant they could not gather ground markings and wreckage distribution information. Using the remaining materials and second-hand information, the NTSB deduced that the flight had reached the stage where landing gears were extended. The report discredited a few possible causes of the accident. Among these included disproving the plane was not airworthy or overweight, while the transferred wreckage showed no signs that the aircraft was brought down by a mechanical failure. In its evaluation, the NTSB determined the probable cause was that the flight's descent was below its altitude clearance limit. While it was unable to explain why this occurred, the poor visibility and presence of snow prompted by the weather was a potential crash contributor.
The NTSB assessed that the surviving wreckage contained no signs of in-flight fire, bullet or explosion damage. However, it also acknowledged that, at the time of 708's descent and eventual crash, a policeman situated at the Berlin control points heard what sounded like a detonation occurring southwest from the Soviet occupation zone. This contributed to theories that the plane may have actually been shot down as it approached Berlin Tegel. While US officials were quick to deny initial allegations from West German media, several Pan Am personnel from Berlin also believed the plane was compromised. Pan Am had for years been working for the CIA. Ranging from some of its flight attendants being CIA spies, to having some of its aircraft fly off-course and captured key imagery and audio from attached camera ports and antennas, The Wall Museum deemed Pan Am's connections with the CIA to be an "open secret". Considering this, the withholding of key materials, and other Soviet methods of preventing espionage by firing tracer shots to deflect planes away from its bases, some alleged the plane was brought down by an explosion or via bullets. However, NTSB analysis seemingly discredits this theory.
A third theory concerned pilot error. Because it was believed the plane was descending below its altitude clearance limit, the plane's four altimeters may have been incorrectly programmed. Particularly, the Federal Aviation Administration (FAA) believed the altimeter was calibrated to reflect Frankfurt's height, about 100 metres above the sea level. However, Tegel was just 37 metres in comparison. Another theory alleged that Soviet anti-aircraft defence in Estal had recently received radar. Thus, one theory as detailed in Flugplatz Döberitz indicated the new radar might have compromised the radio guidance beam. Nevertheless, the altimeters theoretically should have remained active even in spite of the radar interference. The NTSB estimated the point of impact occurred at 01:41:47 am, meaning that the final transmission was completed by 708's crew just six seconds before the crash. Since the plane crashed in a rather level attitude reflecting an ordinary descent, it noted the crew might not have realised 708's close proximity to the ground.
None of the aforementioned theories have been conclusively proven or debunked, leaving 708's fate unclear. The answers likely could be deduced from the missing components, including those within the scope of lost media such as the flight data and cockpit voice controllers. The recorders are designed and incorporated into planes to resist severe shock and fire, and are considered among the most crucial components for investigating non-survivor plane crashes. Particularly, the cockpit voice recorder would have captured the final 30 minutes of the crew's dialogue and with Berlin Control. Thus, the recorders likely survived the impact and resulting fire, but their whereabouts over the years remains unknown. Even events such as the Soviet Union joining ICAO in 1970, the reunification of Germany in 1989, and the dissolution of Soviet Union in 1991 did not reveal any further details surrounding the recorders' fates.
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- Malaysia Airlines Flight 370 (partially found contents of missing flight recorders from disappeared passenger aircraft; 2014)
- Malév Flight 240 (lost flight recorders and crash investigation reports of fatal passenger aircraft crash; 1975)
- Varig Flight 967 (lost flight recorders and Manabu Mabe paintings of disappeared cargo aircraft; 1979)
- NTSB report into the accident. Retrieved 5th Jan '23
- Bureau of Aircraft Accident Archives summarising the crash and NTSB investigation. Retrieved 5th Jan '23
- The Wall Museum summarising the crash and presenting the main theories surrounding its cause. Retrieved 5th Jan '23
- 27th June 1968 issue of The Victoria Advocate reporting on the NTSB blocking access to the accident site and to more than 50% of the wreckage. Retrieved 5th Jan '23
- Western Allies Berlin detailing the Jak-28P crash on 6th April 1966 and the recovery controversy. Retrieved 5th Jan '23
- National Post detailing Pan Am's connection with the CIA. Retrieved 5th Jan '23
- Flugplatz Döberitz detailing the crash and theorising new Soviet anti-aircraft defence radar may have contributed to the accident (book in German). Retrieved 5th Jan '23
- NTSB explaining the characteristics of cockpit voice and flight data recorders. Retrieved 5th Jan '23
- 21st October 1970 issue of The New York Times reporting on the Soviet Union joining ICAO. Retrieved 5th Jan '23