[Graham Boak]

Depending on the problem, of course, but this is partly the principle behind the "power egg" approach which RR (and Bristol) were pressing for adoption in the early war years, and can be seen on, for example, the Wellington Mk.II, Beaufighter Mk.II, Lancaster, and other some other Merlin types. In this principle the various accessories are mounted directly onto the engine, so are removed with the engine rather than requiring an additional number of actions to separate the engine from the airframe.

The arguments for this are more rapid engine changes improving serviceability of the aircraft, and more work/money for the engine company. The downside is that a standardised engine installation is rarely the best for all aircraft, and can produce a considerably reduction in performance. This was displayed with the example of installing these standard "power egg" installations on a Mosquito, but the benefits of integrating ancillary systems with the airframe can also seen in the very low drag of the cooling installation of a Mustang.