18-in Fiume Mark I Torpedo
The 18-in Fiume Torpedo was a torpedo manufactured by Whitehead from 1890 onward. Before the advent of the Mark II model, it was commonly referred to as the 18-in Fiume Torpedo.
Like a slightly later R.G.F. model, it was built in both "long" and "short" versions.
In 1919, it was approved to break up all 18-in Weymouth and Fiume torpedoes.[2]
Development
A delivery of 150 18-in torpedoes from Fiume was completed in 1890, two of which were "short" were found to do 28.44 knots to 800 metres in 65 degree water.[3] The short models gave good results, but had a distressingly high 32 pounds negative buoyancy, making exercise risky.[4][5]
The two trial short torpedoes made 26.3 knots over 800 metres at Fiume and 25.93 knots over 600 yards at Horsea, with Horsea's water being 64 degrees. This was less than test articles of the short R.G.F. competitor.[6]
These long and short torpedoes were evaluated in 1890 alongside a long R.G.F. model and proven 14-in designs.[7]
Fired from Seagull while she was at 18 knots, the long Fiume deflected 26 degrees when fired 57 degrees (this angle may be misread from a blurry image) abaft the beam, the same when fired 30 degrees abaft, 22 degrees abeam, and 11.5 at 30 degrees ahead and 5 degrees at 60 degrees ahead. The short torpedo generally did a little better except at the last angle: 21, 17, 17, 6 and 7 degrees. When these deflections were allowed for, the long Fiume would have been lost on 4/23 shots, and the short Fiume on 5/14 versus just 2/20 for a long R.G.F. Mark I model.[8]
Second Order
In 1891, a second order of 100 torpedoes was made to a slightly improved design of 18 refinements.[9]
In 1896, one of these was adjusted at Horsea, making 25.82 knots at 600 yards in 63 degree water.[10]
Mark I*
This model appeared in 1902. They were converted Mark Is with a steel afterbody, a Mark IV type of valve group and balance chamber mechanism.[11]
Footnotes
- ↑ Annual Report of the Torpedo School, 1890. Plate 1.
- ↑ Annual Report of the Torpedo School, 1919. p. 11.
- ↑ Annual Report of the Torpedo School, 1890. p. 29.
- ↑ Annual Report of the Torpedo School, 1890. pp. 22-4.
- ↑ Annual Report of the Torpedo School, 1891. p. 6.
- ↑ Annual Report of the Torpedo School, 1891. p. 6.
- ↑ Annual Report of the Torpedo School, 1890. pp. 22-4.
- ↑ Annual Report of the Torpedo School, 1890. p. 32.
- ↑ Annual Report of the Torpedo School, 1891. pp. 5,25-6.
- ↑ Annual Report of the Torpedo School, 1896. p. 42.
- ↑ Annual Report of the Torpedo School, 1902. p. 23.
Bibliography
