The reconnaissance aircraft S 6 (S = Spaning,
reconnaissance) Fokker/CVM C.VD were intended to be
replaced with S 7 Hawker Harts in the latter 1930's, but
the Harts were instead employed as bombers, with the
designation B 4. It was found that the B 5 Saab Northrop
8-A 1 was not suitable for reconnissance and artillery
spotting, as the visibility was too limited.
In 1938, ASJA (AB Svenska Järnvägsverkstädernas Aeroplanavdelning) offered to build a trial aircraft for the air force, either Gassner F-1 or their own L 10 which had been started in 1937. As Fieseler Storchs had been purchased for artillery spotting, that requirement was already filled, and the air force ordered two ASJA L 10s, designated P 7 (P = prov, trial).
The L 10 had mostly been designed by the 40 Americans working for ASJA/SAAB. It was a modern all metal design with flush rivets and in some respects was similar to Kingfisher and Helldiver.
As a dive bomber, the wing had to be strong, so the landing gear was not retracted into the wing, but folded back under it, covered by an aerodynamic fairing. When lowered, it was intended to be used as an airbrake (which had been a good solution if the hydraulic system had been powerful enough to extend the gear quickly and evenly). Skis could also be fitted. Later there was also a floatplane version.
It had a very roomy cockpit for the crew of two, the pilot and the observer/radio operator who could slide his seat back and forward between his different work stations. Fixed armament was two forward firing 8 mm guns in the wings, and one for the radio operator.
The air force had assigned the designation S 15 for the reconnaissance version and B 8 for the bomber. But at this time they figured out it would be more logical to give each aircraft type a single number, and Saab L 10 was the first to be given a number in this series: B 17.
The first prototype flew in spring 1942 , with a Bristol Mercury XII 880 hp engine, the same as used in the SAAB built Junkers 86s. Production aircraft were to have 1065 hp Pratt and Whitney SC3-G Twin Wasps. Due to the outbreak of the war, licence to produce it wasn't given, instead it was reverse engineered by SFA (and licence given retroactively after the war, for USD (or was it SEK?) 1).
The chronologically first production version was give 980 hp Mercury XXIV engines, which NOHAB already licence produced for Junkers 86.
It was made in two main versions, reconnaissance and bomber.
Of the bomber 54 were made between 1939 and 1942. They were used as such until 1945, when 44 were converted in to reconniassance aircraft.
This was the only dive bomber version, and as such it was fitted with a trapeze to make the 500 kg bomb clear the propeller. It could also carry bombs under the wings.
It also had an advanced bomb sight, SAAB M41, which was later exported to among others the USAF.
The light level bombing version utilized the internal bomb bay as well as the hardpoints under the wings.
The reconnaissance version, which entered service in 1942, was fitted with a camera in the fuselage. In service it replaced S 5 HE 5 Hansa and S 6 Fokker C.VD/C.VE.
![[S 17]](../img/fvmus96/s17.jpg)
The land version looked very similar to the bomber version
and a total of 65 (of which 44 ex bombers) remained in
service until 1949.
The floatplane version (S = Sjö, sea or lake) was fitted with twin floats, with large, single, aerodynamic struts and given small endplates on the stabilisers. A total of 56, of which 18 were ex B 17BLs, served until 1949.
A few were sold to civilian operators.
At the same time the air force purchased Reggiane Re 2000, they also purchased more engines and propellers of the same type, 1040 hp Piaggio P XI bis RC 40D, which was fitted to the second production version. 77 were produced in 1942-43. Due to problems with spares supplies to the engines, they were all retired in 1947-48.
Weapons fit was the same as B 17B II.
During late 1942, the Twin Wasp copy, STWC-3 with 1065 hp,
was ready, and until 1944 132 B 17As were delivered to the
air force where they remained in front line service until
1948 and for other duties, like target towing, until 1955,
as they were considered reliable and robust.
![[Target towin winch]](../img/b17/b17_tt.jpg)
A few were
also sold to civilan operators.
Weapons fit was identical to B 17B II to begin with, but some were converted to carry ground attack rockets.
B 17A B 17B S 17BS B 17C
Span 13.7 m 13.7 m 13.7 m 13.7 m
Length 9.8 m 9.8 m 10.0 m 10.0 m
Height 4.0 m 4.0 m 4.8 m 4.15 m
Wing area 28.5 m2 all versions
Empty weight 2600 kg 2635 kg 2700 kg 2680 kg
Operating weight 3790 kg 3605 kg 3825 kg 3870 kg
Warload 500 kg 700 kg 700 kg
normal load was 450 kg for all versions
Top speed 435 km/h 395 km/h 330 km/h 435 km/h
Cruise speed 390 km/h 375 km/h 315 km/h 370 km/h
Range 1800 km 1400 km 2000 km 1700 km
Max altitude 8700 m 8000 m 6800 m 9800 m
During 1947-53 46 B 17As were exported to the Ethiopian air force, which at that time had several ex-Swedish air force personnell employed.
The Danish Brigade, which was formed in 1943 in Sweden, had an air arm with 15 pilots who were allowed to take part in Swedish air force training and exercises.
In 1945, 15 B 17Cs were loaned to the Danish Brigade and on May 4:th they were painted in Danish colours and were loaded and ready for take of on the 5:th, but they never got permission to take off in order to arrive in Denmark along with the rest of the Danish Brigade.
These 15 aircraft were offered to Denmark, but seven days after the cease fire the pilots and mechanics were ordered to go to Denmark by train, and the Danish government said they weren't interested in purchasing the B 17s.
Two S 17BS were sold to Osterman Aero and was entered in the civlian aircraft register in 1949/50. They were used for miscellaneous duties, among them the flying fish and shellfish from Bergen in Norway to Stockholm. This cargo was carried in the floats which had been modified with doors.
A total of 19 B 17A were loaned to the companies Svensk Flygtjänst AB and AVIA and modified for target towing duties. They were still owned by KFF, but got civilian registrations and operated by the companies. The first of them started flying in this duty in 1951 and eventually they were all painted yellow.
At least five of them were fitted with ECM equipment in 1959.
One of the target towing B 17As was sold to Austria in 1957. (It had first been sold to Svensk Flygtjänst so the deal could be done without selling a military owned aircraft.)
In 1960 two target towing B 17As were exported to Finland.
This example was restored to flying condition in 1997, with first post-restoration flight on June 11:th.
It made by Saab in Trollhättan and was delivered to the air force on July 27:th 1943 and served with the second sqn of F 7 at Såtenäs, coded "Blue J" (Blå Johan).
After 398 flying hours it was retired as a bomber in 1948, and started service as a target tug with Svensk Flygtjänst until 1957 and Avia after that until 30:th June 1968 when it was retired with 2730 flying hours and put in storage with the air force museum.
The restoration was a wholly volunteer project, which took only 170 days. Airframe corrosion had been negliable, all instruments were working and didn't need adjustment.
A propeller bearing had to be replaced, but fortunately Avia had included a spare supply with the donation in 1968, so it could be replaced, as was a broken piston (the reason the aircraft was retired when it was).
The wiring insulation needed a lot of work, new fabric for the control surfaces had to be cut and stitched (fortunately people who remembered how could be found).
Tires and hoses were difficult to find, but they were found in Canada and Korea.
A modern radio was also installed, otherwise the aircraft is in original condition.
