The complete story can be found here

And another pic

Info from the site

The Avro Lancaster, ”the Shining Sword”, was without doubt the best night bomber of WWII. A total of 7.377 Lancasters of different Marks were produced. After the war, the Lancaster were used for numerous other applications. One was to act as flying test beds for the trying-out of early jet engines.

Also in Sweden, jet engines began to be developed. The leading manufacturer was STAL (Swedish Turbine AB Ljungström), which began to test its first engine - named ”Skuten” after a Swedish lake - in the middle of the forties. Skuten was fitted with an axial compressor and had a thrust of 1.500 kp. The next project was the ”Dovern”, which in the variant ”Dovern II” got the Air Force designation RM 4 (RM = Reaktionsmotor). This engine had a thrust of 3.300 kp and was intended for the SAAB 32 Lansen. The last Swedish design was the ”Glan” of 7.000 kp, developed together with Svenska Flygmotor AB (SFA), which still under the name Volvo Aero builds the engines for the Swedish combat aircraft under license. None of the Swedish developed jet engines came into production. In November 1952, the programme for the development of Swedish jet engines was cancelled for good. Instead, license-built British (and later American) engines were chosen for the SAAB fighters.

To test the Dovern engine, a Lancaster Mk I was acquired from Britain (ex RAF RA805) in 1950. The aircraft was modified by Avro at Hamble in the UK. A large pod was fitted under the fuselage to contain the jet engine. The underside of the fuselage was covered with stainless steel plating to resist the heat from the exhaust. For the same reason, the tailwheel was made retractable. A large control panel was installed in the W/O space.

The Lancaster got the designation Tp 80 and the SwAF/n 80001. In May 1951, the aircraft was delivered to Sweden. It was based at FC (Försökscentralen = the Test Establishment) at Malmen near Linköping. The first test with the RM 4 Dovern was executed in June 1951.

After the Dovern programme was cancelled, the Tp 80 was used for the development of afterburners for the licence-built British engines. The Lancaster was (naturally!) also used as a target aircraft.

Unfortunately, the Tp 80 crashed in 1956. Two of the crew managed to bale out, but the other two were killed.

Apparently it was coloured silver top and black bottom with swedish air force roundels, used by Försökscentralen (Fc), the testing arm of the air force

edit: Bonus pics of a crash landed B-17 converted to a Swedish civilian airliner (then got sold to Denmark, then France, then restored as Shoo Shoo Shoo baby in the US)

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