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Hi Peril,
I'm afraid I don't have one. In fact, I have found Merlin curves to be somewhat inconsistent in general, which is quite surprising considering that this is the engine Hooker et al. based their "Performance of the Super-Charged Aero-Engine" on.
Regards,
Henning (HoHun)
29.04.1941 - Spitfire V X.4922: Merlin 45 @ 3000 rpm/+9 lbs all-out level, 2850 rpm/+9 lbs climb, increased to 3000 rpm above ca. 25000 ft
18.06.1941 - Spitfire VB W.3134: Merlin 45 @ 3000 rpm/+9 lbs all-out level, 2850 rpm/+9 lbs climb, increased to 3000 rpm above ca. 25000 ft
xx.01.1942 Merlin 45 type test +16lbs boost. (The Merlin 100 series. RR Heritage Trust).
03.01.1942 - Ministry of Aircraft Production mentions +12 lbs and +15 lbs boosts
08.03.1942 - Spitfire Vc AA.873: Merlin 45 @ 3000 rpm/+9 lbs all-out level, 2850 rpm/+9 lbs climb, increased to 3000 rpm above ca. 20000 ft
30.06.1942 - No. 129 sqn ORB, speed tests at +16lbs boost.
29.07.1942 - R.D.T.3. R.D.E.2. R.T.P.7 Increased Rating for Merlin Engines. Approval 3,000rpm +16lbs boost Merlin 45,46 and 47 engines, operational units of Fighter Command. Previously only applicable to Seafire aircraft and for special applications. 3 minutes duration.
xx.08.1942 - Air Ministry issues memorandum declaring conversion to +16 lbs is currently done
25.11.1942 - Spitfire VC AA.878: Merlin 45 @ 3000 rpm/+16 lbs climb and level
27.01.1943 - Spitfire VB W.3322: Merlin 45 @ 3000 rpm/+9 lbs all-out level, 2850 rpm/+9 lbs climb, increased to 3000 rpm above ca. 20000 ft, 3000 rpm/+12 lbs take-off
03.02.1943 - 1 Sqn (Spitfire V tropicalized and Aboukir filter) clipped wings and +18lbs boost. SB.45457 Performance improvements on Spitfire F Mark V.
12.02.1943 - RAAF clears Merlin 46 and 47 for use of +12 lbs
25.05.1943 - Spitfire VB W.3228: cropped Merlin 50 @ 3000 rpm/+18 lbs climb and level
Makes little sense based on the data I have seen.
The SC ratios and size differed and the curve should differ in FTH and low end hp. The 46/47 curve should not achieve the same path as the Merlin 45 above FTH from my understanding.
It should over take it and sit above it at higher alts. What you have drawn below is a Merlin 45 with different boost levels.
Thanks.