Saab 17

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Swedish dive bomber

title: "Saab 17" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["saab-aircraft", "1940s-swedish-bomber-aircraft", "single-engined-tractor-aircraft", "mid-wing-aircraft", "aircraft-first-flown-in-1940", "aircraft-with-retractable-conventional-landing-gear", "single-engined-piston-aircraft"] description: "Swedish dive bomber" topic_path: "geography/sweden" source: "https://en.wikipedia.org/wiki/Saab_17" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Swedish dive bomber ::

::data[format=table title="Infobox aircraft"]

FieldValue
nameSaab 17
imageSAAB B17-20 - Flickr - Ragnhild & Neil Crawford.jpg
typeReconnaissance-dive bomber
national_originSweden
manufacturerSAAB
first_flight18 May 1940
introductionMarch 1942
retired1977 (Ethiopia)
primary_userSwedish Air Force
more_usersImperial Ethiopian Air Force
Royal Danish Air Force
produced1941–1944
number_built326 (including 2 prototypes)
::

|name=Saab 17 |image=SAAB B17-20 - Flickr - Ragnhild & Neil Crawford.jpg |type=Reconnaissance-dive bomber |national_origin=Sweden |manufacturer=SAAB |designer = |first_flight=18 May 1940 |introduction=March 1942 |retired=1977 (Ethiopia) |primary_user=Swedish Air Force |more_users=Imperial Ethiopian Air Force Royal Danish Air Force |produced=1941–1944 |number_built=326 (including 2 prototypes) The Saab 17 is a Swedish single-engine monoplane reconnaissance dive-bomber aircraft of the 1940s originally developed by ASJA prior to its merger into Saab. It was the first all-metal stressed skin aircraft developed in Sweden.

Design and development

::figure[src="https://upload.wikimedia.org/wikipedia/commons/a/a3/Assembly-Halls-with-B17-planes-in-Trollhättan-142370502302.jpg" caption="B 17s in [[Trollhättan]] assembly hall in 1944"] ::

The project was initiated in response to a 1938 request from the Flygvapnet (Swedish Air Force) for a reconnaissance aircraft to replace the obsolete Fokker S 6 (C.Ve) sesquiplane. Design work began at the end of the 1930s as the L 10 by ASJA, but once accepted by the Flygvapnet it was assigned the designations B 17 and S 17 for the bomber and reconnaissance versions respectively, and it became better known as the Saab 17.

The design chosen was a conventional mid-wing cantilever monoplane with a long greenhouse canopy and a single radial engine in the nose. Control surfaces were covered in fabric but the remainder was stressed-skin duraluminum. It could be fitted with wheels or skiis, both of which retracted straight to the rear along the underside of the wing, leaving prominent fairings, and when fitted with wheels the undercarriage doors could be used as dive brakes. A retractable tailwheel was provided. A floatplane version was built in small numbers for coastal reconnaissance to replace the obsolete Svenska Aero S 5, with massive fairings joining the floats to the wings where the wheels would have been. To maintain stability small vertical fins were added to the horizontal stabilizer. The wings were reinforced so that it could be used as a dive bomber. Bomb racks were provided under the wings, along with a small bomb bay below the cockpit, although some examples used a conventional rack on the centreline. On the bomber versions, a crutch was fitted to swing the bomb clear of the aircraft in vertical diving attacks, when the bomb could otherwise have passed through the propeller. The reconnaissance versions lacked the crutch. Split flaps broken into four segments were fitted to the underside trailing edge of the wing.

Two L 10 prototypes were ordered, the first being powered by a 880 hp Bristol Mercury XII radial engine built by Nohab in Sweden, and the second with an imported 1065 hp Pratt & Whitney R-1830 Twin Wasp C radial.

Supplies of suitable engines remained a major problem, and resulted in the aircraft being built in three versions with different engines. The definitive B 17A used the Swedish-built STWC-3 (Swedish Twin Wasp C-3), an unlicenced copy of the R-1830. The B 17B used a Bristol Mercury XXIV built by Svenska Flygmotor AB (SFA) in Sweden, and the B 17C used an imported 1060 hp Piaggio P.XI radial from Italy. The United States government denied a request to purchase a licence to build the Twin Wasp, so an unlicensed, reverse engineered copy was built instead as the STWC-3 (Swedish Twin Wasp C-3) to supplement and replace the lower powered Mercury radials already being built under licence. Until production caught up with demand, the earliest aircraft being delivered were flown to their destinations, the engines were removed and shipped back, to be used on the next aircraft to be delivered.

Operational history

::figure[src="https://upload.wikimedia.org/wikipedia/commons/1/1d/Saab_B_17B_on_ground.jpg" caption="Saab B 17B showing bombing crutch under the fuselage needed to allow the bomb to clear the propeller during a dive, and the large undercarriage doors which acted as dive brakes"] ::

::figure[src="https://upload.wikimedia.org/wikipedia/commons/e/e9/Saab_B17B_in_the_air.jpg" caption="Saab B 17B in flight"] ::

The first flight was on 18 May 1940 and first deliveries of dive bombers to the Flygvapnet began in March 1942,

A B 17 was used to test the ejection seat Saab had developed for use in the Saab 21 pusher fighter, which was first successfully fired on 27 February 1944 with a dummy.

Stig Wennerström gained some fame in Sweden for successfully bailing out from a B 17 from low altitude, with his gunner, but would later become a spy for the Soviet Union.

For several months in late 1944 and early 1945 fifteen B 17As were operated by the Danish Brigade in Sweden (Danforce) a unit of 5000 men (including 50 airmen) in Sweden which had been formed to assist in liberating occupied Denmark from the Nazis, and preventing the retreating German soldiers from using civilians as human shields, and carrying out scorched earth tactics as they had done elsewhere. However, due to the German surrender on 7 May 1945, the aircraft were no longer needed and were returned to Flygvapnet control a couple of months later.

Rapid advances in aviation related to improved aerodynamics, higher engine power and finally the introduction of jet engines, resulted in it having a short career, and it was gradually withdrawn from frontline service between 1948 and 1950, while the last examples were retired from secondary roles by 1954. Over the next few years, examples would be sold off to various operators.

Due to the efforts of Carl Gustaf von Rosen, the Imperial Ethiopian Air Force bought 47 B 17As which were operated from 1947 Ethiopian B 17s were used to suppressed the 1960 coup attempt in Addis Ababa. Several aircraft were stationed at Kebri Dahar in Ogaden during the 1964 conflict with Somalia. By late summer 1977, the 3rd Squadron based at Dire Dawa was deactivated and its remaining twelve B 17s were stored at the airbase. During the Ogaden War, eight B 17s that were stored at Dire Dawa airbase were destroyed by Somali bombardment in August 1977.

From 1951, 19 B 17s were loaned to Svensk Flygtjanst AB and AVIA for use as target tugs and painted yellow with civilian markings.

Variants

Company designations

;L 10 :internal ASJA/Saab designation; two produced ::figure[src="https://upload.wikimedia.org/wikipedia/commons/7/79/Saab_S_17BS.jpg" caption="Saab S 17BS mounted on floats"] ::

;L 10A :internal ASJA/Saab designation for 17A, B, and C ;L 10BL :internal ASJA/Saab designation for S17BL ;L 10BS :internal ASJA/Saab designation for S17BS

Flygvapnet designations

;P 7 :L 10 development prototypes

;B 8 :Preliminary designation for bomber version of L 10, not used ::figure[src="https://upload.wikimedia.org/wikipedia/commons/7/75/Saab_B_17C.png" caption="Saab B 17C in flight. The three main versions could be distinguished by their intakes and exhausts. The 17A had a single intake centred on the top of the cowling, the 17B had a single intake offset to [[starboard]] along with a prominent exhaust on the same side, and the 17C had two intakes on either side of the top"] ::

;B 17A :Bomber with 1065 hp Svenska Flygmotor Aktiebolaget (SFA)-built STWC-3 (Pratt & Whitney R-1830-S1C3G Twin Wasp) radial engine; 132 built ;B 17B :Bomber with 980 hp SFA-built Bristol Mercury XXIV radial engine; 55 built ;B 17C :Bomber with 1060 hp Piaggio P.XIbis R.C.40D radial engine; 77 built

;S 15 :Preliminary designation for reconnaissance version of the L 10, not used ;S 17BL :Reconnaissance version of B 17B with wheeled or ski landing gear; 21 built ;S 17BS :Reconnaissance version of B 17B with floats, powered by a Bristol Mercury XXIV engine; 38 built

A total of 326 Saab 17 aircraft of all types were produced, and some bombers were converted into reconnaissance aircraft.

Operators

::figure[src="https://upload.wikimedia.org/wikipedia/commons/2/21/17320_Danmarks_Tekniske_Museum.jpg" caption="Saab B 17A displayed in [[Helsingør]] in Danish markings"] ::

;

Surviving aircraft

::figure[src="https://upload.wikimedia.org/wikipedia/commons/d/d1/Saab_B17A_Fv17239_1.jpg" caption="Saab B 17A flown by the [[Swedish Air Force Museum]]. A second B 17 is displayed in the museum."] ::

Five Saab 17s are known to be in existence today, three of which are on public display.

The Swedish Air Force Museum in Linköping has two aircraft in their collection, a S 17BL '5', serial 17005 which is on static display in the museum, and a B 17A '7', serial 17239, the latter being kept in airworthy condition and which is periodically flown.

Another B 17A 'E', serial 17320 which was donated by the Flygvapnet after having served as a target tug is on display at the Danish Museum of Science and Technology in Helsingør/Elsinore.

Two former Ethiopian B 17As were recovered in the 1990s and purchased by a South African collector as a part of a large batch of ex-Ethiopian aircraft. These were shipped to Lithuania but their current status and location is unknown following the collapse of the collector's business interests.

Specifications (B 17C)

|ref=Saab Aircraft since 1937 |prime units?=met |crew= Two |capacity= |length m=10 |span m=13.7 |height m=4.5 |wing area sqm=28.5 |airfoil= |empty weight kg=2680 |gross weight kg=3870 |eng1 number=1 |eng1 name=Piaggio P.XIbis R.C.40D |eng1 type=14 cylinder air-cooled radial piston engine |eng1 hp=1060 |prop blade number=3 |prop name=Piaggio P.1001 variable pitch propeller |prop dia m= |max speed kmh=435 |cruise speed kmh=370 |minimum control speed kmh=125 |range km=1700 |ceiling m=9800 |climb rate ms=10 |wing loading kg/m2=139 |power/mass=0.220 kW/kg |guns=

  • 2 × fixed forward-firing 8 mm Flygplanskulspruta Ksp m/22F (M1919 Browning AN/M2) machine guns

  • 1 × rear cockpit flexible 8 mm Flygplanskulspruta Ksp m/22R (M1919 Browning AN/M2) machine gun |bombs=

  • 700 kg of bombs could be carried. Racks were provided under the wings, in an internal bomb bay and externally on the fuselage centreline.

References

Citations

Bibliography

References

  1. Annerfalk, 1999, p.58
  2. Karlström, 1988, p.52
  3. "B 17 – Saab 17 (1941–1955)".
  4. Annerfalk, 1999, p.84
  5. (June 2020). "Fpl 17 – Saabs första konstruktion". Svensk Flyghistorisk Tidskrift (Swedish Aviation History Journal).
  6. Annerfalk, 1999, p.95
  7. Annerfalk, 1999, p.144
  8. Annerfalk, 1999, p.100
  9. until 1977.Cooper, 2014, p.9
  10. Cooper, 2014, p.12-13
  11. Cooper, 2014, p.16
  12. Cooper, 2014, p.26
  13. Cooper, 2014, p.39
  14. Cooper, 2014, p.58
  15. Annerfalk, 1999, p.59
  16. Poelstra, Jack. "SE-BYH Saab B 17A c/n 17239 - Swedish Air Force Museum - Groningen Airport Eelde in Holland - 7 July 2005".
  17. "Baltbound Bombers – 2".
  18. Andersson, 1989, pages 59–65

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