Interflug Flight 450

Interflug Flight 450
An Interflug Il-62, similar to the one involved in the crash
Accident
Date14 August 1972
SummaryIn-flight fire leading to mid-air breakup
Site
Aircraft
Aircraft typeIlyushin Il-62
OperatorInterflug
IATA flight No.IF450
ICAO flight No.IFL450
Call signINTERFLUG 450
RegistrationDM-SEA
Flight originBerlin-Schönefeld Airport, Schönefeld, East Germany
DestinationBurgas Airport, Burgas, Bulgaria
Occupants156
Passengers145
Crew11
Fatalities156
Survivors0

Interflug Flight 450 was a holiday charter flight to Burgas, Bulgaria operated by an Ilyushin Il-62 that crashed shortly after take-off from Berlin-Schönefeld Airport in Schönefeld, East Germany, on 14 August 1972. The accident was caused by a fire in the aft cargo bay which spread quickly, destroying the aircraft's structural integrity. All 156 passengers and crew died. To this day, it is the deadliest aviation accident to occur on German soil and the third deadliest accident involving an Ilyushin Il-62.

Aircraft and crew

The aircraft was an Il-62 registered DM-SEA, with serial number 00702. It was the first Il-62 delivered to Interflug and entered service in April 1970. It was handed over to the airline to mark the centenary of the birth of Vladimir Lenin. By the time of the accident, it had flown about 3,520 hours.

The captain, Heinz Pfaff, aged 51, had joined the East German Deutsche Lufthansa in 1956 and remained with the airline when it was merged into Interflug in 1963. He had flown the Aero 45, the Ilyushin Il-14 and the Ilyushin Il-18, and had flown the Il-62 since its introduction at Interflug in 1970.: 409  He had about 8,100 flight hours and had flown more than four million kilometres.: 409  The first officer, Lothar Walther, aged 35, had been with Interflug since 1961 and had 6,041 flight hours.: 409  The navigator, Achim Filenius, aged 38, had joined Deutsche Lufthansa in 1955 and had 8,570 flight hours.: 409  He had survived an air crash near Königsbrück in 1963.: 409  The flight engineer, Ingolf Stein, aged 32, had been with Interflug since 1963 and had 2,258 flight hours.: 409  The cabin crew consisted of four flight attendants.: 409 

Accident

Flight 450 was a holiday flight from Berlin-Schönefeld to Burgas, on Bulgaria's Black Sea coast, with 148 passengers on board. The aircraft took off at 16:29 local time.: 294ff.  At about 16:43, while flying at an altitude of about 8,900 m (29,200 ft) south-east of Cottbus, about 100 km (62 mi) from Berlin, the crew noticed problems with the trim of the horizontal stabiliser.: 294ff.  A minute later, after consulting air traffic control, the crew turned back towards Schönefeld.: 294ff.  At 16:51, the crew decided to dump five tonnes of fuel to avoid an overweight landing, and dumping began three minutes later.: 294ff.  The aircraft then turned left towards the Hotel Mike radio beacon south of Storkow, which it passed shortly afterwards.: 294ff. 

At 16:59, the crew made a final distress call, reporting increasing problems with pitch control: "Mayday, Mayday, Mayday. Impossible to hold altitude, we had a fire, we are having difficulty with the elevator control.": 294ff.  As the aircraft continued to descend, the rear fuselage, carrying the horizontal and vertical stabilisers, separated from the aircraft, which lost all stability and control.: 294ff.  The aircraft pitched over, and the resulting aerodynamic loads tore off part of the forward fuselage and parts of the wings in the air.: 294ff.  The wreckage struck the ground at 17:01, 400 to 600 m (1,300 to 2,000 ft) east of the edge of Königs Wusterhausen.: 294ff.  All 156 people on board were killed.

According to a 2022 article in the Frankfurter Allgemeine Zeitung, an emergency landing at the nearer airfield at Cottbus might have saved many lives. The article suggests that Pfaff, an experienced captain, probably did not attempt it because the crew could not have known how serious the situation was.

Investigation and aftermath

The East German aviation inspectorate, the criminal police and the Ministry for State Security investigated the accident in detail, and their files are preserved in the German Federal Archives. Interflug's Il-62s were grounded during the investigation. In the Il-62, an inaccessible space outside the pressurised cabin in the tail contained ducts that carried hot, pressurised bleed air at 300 °C (572 °F) from the engines to the air-conditioning system.: 294ff.  A leak in these ducts damaged the insulation of nearby electrical cables, causing a short circuit with arcing that ignited magnesium alloys in the structure at temperatures of up to 2,000 °C (3,630 °F).: 294ff.  The damaged cables had already caused the trim problems shortly after take-off. Sparks started a fire in the rear cargo area, where flammable de-icing fluid was stored and also caught fire. At the time, the Il-62 had no fire detectors in the tail section, and there was no view from the cabin into the rear compartment, so the crew did not notice the fire and was unaware of the extent of the problem. The fire weakened the tail section until it separated from the fuselage together with the entire tail unit. The investigating commission concluded that leaking hot-air ducts in the unpressurised tail section had caused the crash, which made it the result of a design flaw.: 294ff.  The Ilyushin design bureau, whose general designer Genrikh Novozhilov took part in the investigation, never confirmed this finding.: 294ff. : 110–111 : 58  Out of consideration for the Soviet Union, the East German authorities never officially announced the cause.

The Il-62 was nevertheless modified in line with the commission's proposals, with additional fire detectors, fire-extinguishing equipment and a viewing window in the partition to the tail compartment. Additional periodic inspections, known as "special air-conditioning checks", were also introduced. No further problems of this kind occurred in Interflug's later operation of the Il-62.

Memorials

Memorial at the cemetery in Wildau
Memorial plaque in Königs Wusterhausen

The 60 victims who could not be identified were buried in a common grave at the cemetery in Wildau, in the district of Hoherlehme, marked by a memorial stone bearing their names. The other victims were buried in their home towns. The first public commemoration of the disaster was held on its 40th anniversary in 2012. A memorial stone near the crash site was created on the private initiative of a local eyewitness, and a new memorial plaque was unveiled at the site on the 50th anniversary in 2022. In August 2024, a street in Königs Wusterhausen, Am Wasserwerk, was renamed Heinz-Pfaff-Straße in honour of the captain, whose actions were credited with preventing the aircraft from crashing into a residential area.

The disaster was the subject of Der Todesflug der IL 62 ("The Death Flight of the Il-62"), a 1998 documentary by Jens Stubenrauch and Titus Richter in the Mitteldeutscher Rundfunk series Vergessene Katastrophen ("Forgotten Disasters"). It was also covered in a 2022 episode of the German podcast Flugforensik.

See also

References

  1. ↑ Denes, Benjamin; Spaeth, Andreas (13 August 2022). ""Mayday! Kurs 90 Grad, unmöglich Höhe zu halten."" ["Mayday! Course 90 degrees, impossible to maintain altitude."]. Berlin-Brandenburg Broadcasting (in German). Retrieved 14 August 2022.
  2. ↑ "156 Are Killed in Air Crash In a Suburb of East Berlin". The New York Times. Vol. 121, no. 41842. 15 August 1972. ISSN 0362-4331.
  3. 1 2 Ranter, Harro. "Accident Description". Aviation Safety Network. Flight Safety Foundation. Retrieved 18 May 2020.
  4. ↑ "Stotterndes Geheul" [Stuttering howl]. Der Spiegel (in German). Spiegel-Verlag. 21 August 1972. Archived from the original on 5 November 2013.
  5. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Ritter, Gerd (17 August 2017). "DM-SEA". Interflug.biz (in German). Archived from the original on 9 June 2026. Retrieved 22 October 2026.
  6. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Huber, P. (16 August 2022). "Vor einem halben Jahrhundert: Urlaubsflug in den Tod – der Absturz von Interflug 450" [Half a century ago: A holiday flight to death, the crash of Interflug 450]. Austrian Wings (in German). Archived from the original on 27 September 2023. Retrieved 10 September 2023.
  7. ↑ "Stotterndes Geheul" [Stuttering howl]. Der Spiegel (in German). No. 35. 21 August 1972. pp. 58–59. Archived from the original on 30 April 2019. Retrieved 14 April 2013.
  8. 1 2 3 4 5 6 7 Flieger Revue, No. 10, 1972.
  9. 1 2 ""Mayday! Kurs 90 Grad, unmöglich Höhe zu halten."" ["Mayday! Heading 90 degrees, impossible to hold altitude."]. rbb24 (in German). 14 August 2022. Archived from the original on 26 September 2023. Retrieved 10 September 2023.
  10. 1 2 3 4 5 6 7 8 9 10 11 12 13 Seifert, Karl-Dieter (2008). Weg und Absturz der Interflug: Die Geschichte des Unternehmens [The Rise and Fall of Interflug: A History of the Company] (in German). Zweibrücken: VDM. ISBN 978-3-86619-030-6.
  11. ↑ Ranter, Harro. "ASN Aircraft accident Ilyushin 62 DM-SEA Königs Wusterhausen". aviation-safety.net. Aviation Safety Network. Archived from the original on 3 January 2024. Retrieved 25 August 2018.
  12. ↑ "Vor 40 Jahren: Absturz bei Königs Wusterhausen" [40 years ago: The crash near Königs Wusterhausen]. airliners.de (in German). 14 August 2012. Archived from the original on 27 August 2019. Retrieved 24 June 2016.
  13. 1 2 3 4 5 Denes, Benjamin; Spaeth, Andreas (12 August 2022). "Die verdrängte Katastrophe: Vor 50 Jahren ereignete sich bei Königs Wusterhausen das schwerste Flugzeugunglück in Deutschland" [The suppressed disaster: Fifty years ago, Germany's worst air crash happened near Königs Wusterhausen]. Frankfurter Allgemeine Zeitung (in German). p. 6.
  14. 1 2 3 4 5 6 Steyer, Claus-Dieter (15 August 2012). "Erstes Gedenken nach 40 Jahren" [First commemoration after 40 years]. Der Tagesspiegel (in German). Retrieved 28 March 2016.
  15. ↑ Billig, Detlef; Meyer, Manfred (2002). Flugzeuge der DDR [Aircraft of the GDR] (in German). Vol. 2. Friedland: TOM Modellbau. ISBN 3-613-02241-9.
  16. ↑ Meyer, Manfred (2000). "Flugzeuge in der DDR: Il-62 – Der "weiße Riese"" [Aircraft in the GDR: The Il-62, the "white giant"]. Flieger Revue (in German). No. 1.
  17. ↑ "Interflug-Absturz 1972: Straße in Königs Wusterhausen nun nach Pilot benannt" [Interflug crash of 1972: Street in Königs Wusterhausen now named after the pilot]. rbb24 (in German). 1 August 2024. Retrieved 14 August 2024.
  18. ↑ Jens Stubenrauch, Titus Richter (1998). Der Todesflug der IL 62 [The Death Flight of the Il-62] (Television documentary). Vergessene Katastrophen (in German). Mitteldeutscher Rundfunk.
  19. ↑ "Episode 5: Interflug IF 450 – Die Katastrophe von Königs Wusterhausen" [Episode 5: Interflug IF 450, the Königs Wusterhausen disaster]. Flugforensik – Abstürze und ihre Geschichte (Podcast) (in German). 6 July 2022.