Appendix VI: Main Engines
This Appendix is divided into two parts VIA and VIB as follows:
- APPENDIX VIA - Gives the results of bench tests carried out by Vickers on the engines for the various vessels named. The engines for the HOLLAND Class to A12 were Wolseley type petrol engines and for A13 a Hornsby-Ackroyd diesel. The remainder were Vickers design engines.
- APPENDIX VIB - Gives information on the engines for those boats up to L Class not covered in Appendix VIA and for all vessels thereafter.
- A11 engines were 4-cycle. All the diesel engines had solid injection except for A13 and the D Class which had blast injection.
- Broxburn quality of fuel was used in the tests of the diesel engines except that American Distillate was used for G13, the K Class and M1 - 2.
- Includes the weight of the engine air compressor which was fitted in A13 and the D Class only.
- The actual bhp developed at 400 rev/min was 350 in A1 and 450 in A2 - 4.
- Reversible type engines. The G13 engines were not a success in service and were replaced by standard E type engines.
- Not the main engine.
- In the as built weights, the main engine weight was given a 7.52 tons in the HOLLAND, 7.1 tons in A1, 17.7 tons in A2 - 4 and 16.2 tons in A5 - 12. These weights would include some incidental items in addition to the actual weight of the main engine.
- This figure is considered to be low.