KLM Super Constellation Triton crash at Shannon in 1954

Super Constellation Triton, registered as PH-LKY, operated by KLM Royal Dutch Airlines, was en route from Amsterdam to New York, carrying 46 passengers and a crew of 10. As planned, the aircraft made a refueling stop at Shannon, Ireland on flight number 633, and took off at 02:30, on September 5, 1954. However, just 35-40 seconds after takeoff, the Triton crashed on the mud flats in the Shannon River, approximately 2500m from the end of the runway. Tragically, 25 passengers and 3 crew members lost their lives in the crash.

The plane also carried mail from Burma, which was recovered after the crash and marked with a cachet reading "SALVAGED FROM K.L.M. CRASH AT SHANNON." These cachets are available in two colors: black and violet.

References: 

http://www.cyberbore.com/sansrancune/triton.html
https://aviation-safety.net/photo/6065/Lockheed-L-1049C-Super-Constellation-PH-LKY

1931 Air Orient Aircraft crashed at Sandoway, Burma

Air Orient's Fokker plane V.VIIB PH-AEO, a three-engine aircraft, was en route from Saigon to Paris with Claude Beauregard and Ange Bourgeois as pilots, accompanied by Pierre Patard (Engineer) and Olivier Leroux (Radio Navigator). The journey started from Saigon on 5 Jun, included a scheduled overnight stop in Bangkok (5 Jun), Rangoon (6 Jun) before continuing towards Akyab. However, on June 7, tragedy struck as the plane went out of control and crashed into the Sandoway River due to a storm, resulting in the loss of the entire crew. The aircraft sustained irreversible damage and was beyond repair. 

Registered from Nam-Dinh, to Paris

Registered from Moncay

Despite this, the mail was fortunately recovered a few days later and sent to Paris, arrived on 2 Jul, where it received a black stamp bearing the inscription "COURRIER ACCIDENTE LE 7 JUNE 1931."

Crash cachet applied in France

Reference: John Garner, "A Burma Crash Cover", The Burma Fantail, Vol. 13, No. 1, Whole Number 47, pp. 11-12, January 2016.

Burma Aerogramme found in BOAC "Comet - York Peter" Crash, 1954

The B.O.A.C flight 781 crashed near the Elba Island, Italy on 10 Jan 1954.  The comet was operating the flight from Singapore to London via Rome where it made a stop at 10:30 AM.  20 minutes after take off, from Ciampino airport, the aircraft crashes take place when the Comet broke up in the air, near the Elba island.  All occupants were killed in the accident. 

  

The following day postal bags were recovered by a fishing boat and taken to Genoa by the steamer “Persia”.  The recovered mail bears several different cachets depending on the destination. Covers and aerogrammes sent from Burma to UK were found in these mails.  The aerogramme highlighted below is sent from Rangoon addressed to Scotland.

7 Jan 1954, RANGOON to SCOTLAND. Backstamped London 30 Jan 1954.

Cachet in Red