Svenska Flygmotor AB is owned by AB Volvo and AB Bofors and builds engines for jets and other material for the Swedish air force.

-In addition to notable research work in different fields of aeronautics.

Originally it was known as Nohab Flygmotor AB that was founded in 1930. It built engines under Bristol license: the Mercury and the Pegasus.

-In 1941 it was acquired by AB Volvo to become known (along with other acquisitions of the time) as the SFA or Svenska Flygmotor AB.

-The facilities are spread throughout Sweden, in Göttenborg, Ulvsunda, Skövde and Trollhättan.

-The first jobs as SFA were the construction of DB-603, DB-605 engines (for the Swedish B-18B bomber) and the American Pratt & Whitney Twin Wasp.

-Later, it made the DeHavilland “Goblin 3” and “Ghost 45” engines for the Swedish Vampire and Saab-29. They also built the DH Ghost 50 turbojet.

-The Goblin 3 was called RM-1A and the Ghost was called RM-2 and 2A. From 1955, it acquired licenses from Rolls Royce to build the Avon under the designation of RM5 and RM6.

-The RM5 was an Avon RA7R for the Saab 32.

-The RM6 was the Avon 200 series with afterburner and was fitted on the first Lansen and Draken J-35.

“SFA RM6, with afterburner

-For the Saab Viggen, the license was requested from Pratt & Whitney for the JT8D-1 and the engine was manufactured as RM8.

“Draken vs. Viggen Engine”

-It is worth mentioning that the STAL engines were transferred to SFA, so the “Dovern” that was in the company from the early days was assimilated and then another engine appeared, the “Glan” (No details at the moment).

-The RM12 is the F-404 under license from General Electric, and was destined for the Saab Grippen (see Flygmotor).

-Also with Garrett it made the TPE-331 and TFE-731-5. Also collaborating with the TFE-1042.

-The least known and very notable thing about the company is its own production of ramjets and rockets.

“The RR-1 on a missile”

-The RR-1 engine is capable of performing at speeds of 5-6 Mach. In the photo it appears with two “booster” rockets.

“RR-2 head”

-The RR-2, whose fuel system is shown in the above picture, has an internal compression diffuser (two shock waves) and its speed goes up to 3 Mach.

“SFA RR-2 ramjet”

“VR-3 rocket motors”

-The VR-3 rocket motor weighs 75 kg and can provide up to 2,600 kgf of thrust.

-As already mentioned in the chapter on Flygmotor, the HR-4 hybrid rocket together with other special propulsion projects were the subject of great attention.

“SFA Hybrid Rocket”

-We should not end this chapter without mentioning that the radial piston engines from Pratt & Whitney, such as the 1065 HP one, were known at the SFA as the STWC-3G. It had 14 cylinders in double row and they ended up on the Swedish FFVS J-22 aircraft and the Finnish Myrsky II.

-And less known have been the small engines for light aviation built at the SFA in Trollhättan, such as the 4-cylinder horizontally opposed F-451-A that gave 140 HP at 2,600 rpm. They wer known as “Trollet”, and they were made between 1946 and 1952.

“SFA F-451-A engine”

-Another version is the also horizontally-opposed six-cylinder that was manufactured in the same years. It produced 210 HP.

-As in the Lycoming engines, the air-fuel mixture was passed from the carburetor to the cylinders through the hot oil sump.

-Presumably due to the semi-arctic experience in Sweden.

From Appendix 6: Two executives of the brand showing the RRX-1 ramjet, which was of advanced design for that time. And it was prepared for a wide speed range from 2 to 6 Mach.

“RRX-1 ramjet”

-The RM8 engine is now provided as equipped with afterburner for the SAAB-37 Viggen.

“Svenska Flygmotor RM8 engine”

-There is a small difference between the RM8A and the RM8B. Because the latter has a third stage of the bypass compressor, and therefore it is 2.75 inches longer (about 7 centimeters).

“RM8A and B”

From Appendix 9: A photograph of a Swedish-built RM-1 licensed by the British DeHavilland has been made available at the Malmö museum. It is the Goblin model.

“SFA, RM-1”

From Appendix 12: Below we show a photo of the “STWC-3”, an engine recovered from a B-17 during WWII. See main text.

“SFA-STWC-3 engine” (PiP)

- And detail of the logo on the engine itself.

“SFA logo on engine plate” (PiP)

“An SFA RM5 cutaway ” (PiP)

-See main text for a list of engines built under license. Especially English ones.