Minor nitpick to an otherwise fantastic drawing Heuhen. SÆL was a "torpedobåt av 1. klasse", not 3rd Class like the drawing says. We didn't really have any "torpedobåt av 3. klasse" save for MYG, which was a prototype that didn't really work out that well and was struck in 1920 and sunk during live fire exercises in 1922. For reference, we had at the outbreak of war on April 9, 1940 a total of seventeen torpedoboats under command, ten "torpedobåt av 1. klasse" and seven "torpedobåt av 2. klasse". The boats of "2. klasse" had been built between 1882 and 1912, while the "1. klasse" were built from 1892 until 1901. Of these, KJELL, TRYGG and SNØGG (of the "2. klasse") and BRAND, LAKS and SKREI were captured by the Germans and pressed into service as Vorpostenboots.
Armament was relatively poor, with one to two 37mm revolver cannons, a bow-mounted torpedo tube or two for the "2. klasse", one to two "torpedo cannons" (trainable torpedo launchers, but we like to call them cannons), and small-arms. Crew size was around 21 personnel, with displacement varying from 60 to 260 tons and a top speed of 18-25 knots.
The Norwegian authorities knew perfectly well that the torpedo boat fleet was antiquated, and had started taking steps to replace the aging ships of the fleet, including the torpedo boats, with newer ships. In the case of the torpedo boats, they would be replaced by MTBs from Vosper. Eight boats were ordered in 1939, but the outbreak of WW2 meant that the Royal Navy requisitioned six of them for their own use. The last two (MTB 5 and MTB 6) weren't completed by the time of the invasion, and were delivered to the Norwegian Government in Exile in Britain in May 1940.
As a small digression, I can add that the Norwegian MTB fleet was further increased during the exile years, with a total of 21 boats serving (though never more than 12 simultaniously due to battle losses) with distinction and laying the foundation for the post-war boom in the torpedo boat fleet. The lineage of today's SKJOLD-class coastal corvettes (until two years ago referred to as MTBs, despite a total lack of torpedoes in their design) can be traced back to the "torpedobåt av 1. og 2. klasse" design in both mentality and mission: to protect Norway's coast from foreign invasion. Despite the lack of success of the "1. og 2. klasse" due to their antiquated state, several of the boats did serve with distinction until they were lost in April and May 1940, including SÆL, STORM and STEGG.
Sorry for the disgression, but I felt it appropriate to include a little bit of information and background to the picture Heuhen made.
Oh, and Heuhen: We didn't start with the "HNoMS/KNM" prefix until 1947. Just for info.
good to know, will take to change the text!