Fulmar in 1941/42/43: feasible and/or plausible upgrades?

[RCAFson]

I just discovered that the Merlin 30 was cleared for 16lb boost in late 1941/early 1942:

so my chart with Fulmar II:

(and others) performance at 16lb boost was probably correct to about 4000ft and it would then gradually join the curve for 12lb boost performance.

 

[wuzak]

Interesting that those documents specify MAP in inches of mercury (inHg) rather than the usual, for British aircraft, PSI boost. Was that because the RN operated a number of US types?

 

[RCAFson]

Interesting that those documents specify MAP in inches of mercury (inHg) rather than the usual, for British aircraft, PSI boost. Was that because the RN operated a number of US types?

It appears to be a UK MAP report, and I suspect that it is being written for US consumption.

 

[wuzak]

I don't have access to my books, but wasn't the Merlin 30 a 2 speed unit?

If that is the case, where is the advantage of the Merlin 45?

 

[RCAFson]

I don't have access to my books, but wasn't the Merlin 30 a 2 speed unit?

If that is the case, where is the advantage of the Merlin 45?

The Merlin 30 had a single speed SC but with a smaller rotor and lower gearing than on the 45, so it produced a bit more power at the same boost levels (because of lower losses to the SC), but it could only maintain 16lb boost to ~4000ft on a Fulmar versus 16lb boost at ~13000ft for the 45 on a Spit V.

 

[wuzak]

Still, a XX series would be better than the 45.