To Developers: New engine settings for Merlin III at +12 lbs

[Kwiatek]

When Cliffs of Dover is coming i wonder if 1C has detailed info about new engine settings for Spitfire MK1 +12 lbs with Melin III engine which was intruduced since using 100 octan fuel in engine Merlin III.

With lower octan fuel Merlin III maximum power was + 6 1/2 lbs. I found that most avaliable data claim that after using 100 Octan fuel Merlin III settings were +12 lbs - emergency power and +6 1/2 lbs for climbing power (nominal power) which isnt true.

I just put here document which show which engine settings were used in Merlin III at 100 Octan fuel :



As we see such engine settings are similar to these one in Merlin XII using in Spitfire MK II.

So we should have for Merlin III engine at 100 octan fuel:

- emergency power ( take off) - +12 lbs
- climb power ( rated power) - + 9lbs
- crusing powe - +7 lbs

I think it is important information regarding Spitfire performacne expecially climb and maximum speed at different engine settings.

At spitfireperformacne site we have climb rate for Spitfire MK1 at 6 1/2 lbs 2600RPM :

http://www.spitfireperformance.com/n3171.html

We see that climb rate was 2810 ft/min - 2900 ft/min at low level ( 14-14.5 m/s).

So if we take new engine settings with 100 Octan fuel for climb power at 9 lbs 2850 RMP - climb rate would me much better - ab. 3000-3100 ft/min ( 15-15.5 m/s) and with emergency power at +12 lbs 3000 RPM it would be much more higher.

Being in the topic of engine settings and WW2 fighters planes performacne i just wonder if 1C has detailed info about BOB fighters performance and engine settings to make correct FM and performacne of these planes.

I know that these topic is not simple easy beacuse there are many various information about performance of these planes expecially Bf 109 E and Spitfire MK1.

I wonder also about engine settings for Db601A and 601Aa for 1940 year ( BoB era). There are also various information about maximum allowed ATA - some claim that Ata was restricted for only 1.3 Ata when full emergency power for DB 601 A was 1.42Ata ( 1.45 Ata for 601Aa).

I hope some from 1C would read these topic.