The final version, of which 52 were built, was designated T 18B, as they were intended for anti-shipping attacks with torpedos, entered service in 1947.
It had a more aerodynamic nose section since it from the beginning wasn't intended to have the lower gun, and thus faster. Otherwise it was structurally identical.
In addition to the bombs and rockets carried by B 18B, it was also intended to be able to carry a 1000 kg mine or 950 kg torpedo internally. The torpedo trials weren't successful, so the main armament for anti-ship attacks were rockets, two 20 mm guns in the lower nose and a 57 mm Bofors m/47 L/50 gun which could be mounted in the bomb bay in about two hours, with the muzzle protruding through a hatch in the lower nose. It weighed 735 kg and a total length of 5.3m Magazine capacity was 40 rounds plus one in the chamber. Reloading in the air wasn't possible. Firing rate was 3 rds/s and the maximum practical range for the 2.5 kg HE or AP projectiles was 2000 m. It had a well working recoil damper so in spite of the high recoil force (6 tons) flying properties weren't affected much. Reloading was by pneumatics, firing electric.
Trial armament was two 40 mm guns under the nose, but test firing shattered the nose glazing. The anti-ship missile Rb 302 was also trialled but didn't enter service. The descendant Rb 304/Rb 04 entered service on Lansen and Viggen.
The last ones were retired in 1958 after having been replaced by A 32A Lansen.
