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Flight recorders under water: list of longest periods before recovery
19 June 2016
Air France flight 447 Cockpit voice recorder (CVR) on the sea bed

Air France flight 447 Cockpit voice recorder (CVR) on the sea bed

Twenty-eight days after the accident, both flight records of EgyptAir flight 804 were recovered from the Mediterranean Sea this week.  How does this compare to recorder recovery operations of other commercial aircraft accidents at sea?

According to ASN data the longest period before recovery of a flight recorder was just over eleven years. An Itavia DC-9 passenger plane crashed into the Tyrrhenian Sea, off the Italian island of Ustica on June 27, 1980, killing all 81 on board. Several investigations failed to conclusively establish the cause of the accident.  In 1987 the government appropriated funds for the recovery of the wreckage of the DC-9. Two distinct recovery campaigns, in 1987 and in 1991 , made it possible to bring to the surface some 96% of the wreckage, including both flight recorders. Data was succesfully retrieved from both recorders.

Current flight recorders are tested to specifications as stated in EUROCAE document ED-112A, Minimum Operational Performance Specification for Crash Protected Airborne Recorder Systems. ED-112A states that a flight recorder must be able to withstand sea water immersion for at least 30 days, and a deep sea pressure of 21000 feet / 6100 meters.

ASN data show that there were at least six accidents in which the flight recorders were recovered after this period of 30 days.

days accident accident date retrieval date depth (m)
4038
2535
[FDR] Itavia flight 870
[CVR]
27 June 1980 18 July 1991
6 June 1987
-3500
700 Air France flight 447 1 June 2009 2 May 2011 -3900
415 South African Airways flight 495 28 Nov. 1987 6 Jan. 1989 -4500
238 Adam Air flight 574 1 Jan. 2007 27 Aug. 2007 -2000
59 Yemenia flight 626 30 June 2009 28 Aug. 2009 -670
ca 36 Korean Air flight 007 1 Sept. 1983 ca 7 Oct 1983 -200
28 EgyptAir flight 804 19 May 2016 16 June 2016 -3000
25 China Airlines flight 611 25 May 2002 19 June 2002 -70
24 Tuninter flight 1153 6 Aug. 2005 30 Aug. 2005 -1500
22 Birgenair flight 301 6 Feb. 1996 28 Feb. 1996 -2140
21 Air Moorea flight 1121 9 Aug. 2007 30 Aug. 2007 -670
19 Armavia flight 967 3 May 2006 22 May 2006 -700
18 AeruPeru flight 603 2 Oct. 1996 20 Oct. 1996 -183
17 Air India flight 182 23 June 1985 10 July 1985 -2040
13 Flash Airlines flight 604 3 Jan. 2004 16 Jan. 2004 -900
12 EgyptAir flight 990 1 Nov. 1999 13 Nov. 1999 -70

Note: on 11 November 2015 the flight recorders of an IAI 1124 Westwind ambulance jet aircraft were recovered from depth of 48 m near Norfolk Island, almost six years after the accident (18 Nov. 2009). The recorders were successfully decoded.