Oh absolutely and the difference in the graph between 87 and 100 tested in game appears small - repeat tests may well show the difference is due to random variation between tests rather than a real difference between the models in game. Perhaps I misread your post, I was merely pointing out that there should not be a real difference between 87 and 100 octane without boost.

Something that does seem off in the Spit 1a 100Oct vs 87Oct is engine overheat, particularly in the climb and at altitude (not using boost) where the Spit 1a 100Oct is far more sensitive to overheating and so I find I have to use lower power settings in the 100Oct version currently than in the 87Oct version. I haven't done much testing in the Hurricane versions but it wouldn't surprise me if it was a problem here also. It's important to have people testing the new FM as they are WIP and so they can be modeled properly and it's great that people are doing so.

The big cause for concern at the mo is the difference between the modeled ac and rl performance which is off in both the Spit 1a and Hurricane, I haven't seen much data for the 109 but would love to as it's important that all aircraft in game are modeled as accurately as possible and it may well turn out that the 109 is also suffering under-performance.

No Milo,

I said the Notes on a Merlin Engine does not list 100 Octane as the specified fuel. That points to the extent of use and service.

By January 1942, 100 Octane was common enough for the Notes on a Merlin Engine to distinguish 100 Octane as the fuel for operations and 87 Octane for training.

I can see why you would be confused.

The extent of use and service is pointed to by the expenditure of thousands of tons of 100 octane fuel, numerous RAF documents stating its use during the BofB, numerous combat reports, and pilot accounts of 12lb boost and a complete lack of evidence of the same for 87 octane...but this is an argument long past now.

This issue now is that 87 and 100 octane performance in CLoD is completely FUBARed.

Tht's only your interpretation. It wld be more honest to point it in the right manner.

As for an example and as already said, an article of "Flight" reviewing just after the war's end and written at the occasion of the Merlin anniversary list all Merlin version with the type of fuel used. It does not state any Fighter powered with Merlin using 100oct before 41/42.

More can be said of course. But if all this has been alrdy written it does not mean that it could be swapped out like you did summing it up.

And frankly thinking seriously about it I wonder how you can imagine that a fighter aircraft designed to be operated above the cold seas of the Channel and the North sea would have seen is fuel swapped with as much technical care as a Ford Hotrod boosted for the quarter mile.

The arguement about 100 octane fuel use is over. However, the fact is that the Merlin II/III was engineered for 100 octane use right from the start, so that when 100 octane was approved for RAF FC, it was a simple matter to convert the engines over to 100 octane. The documentation on how this was done, on a per aircraft basis, has been presented here numerous times, but here it is again:
http://www.wwiiaircraftperformance.org/ap1590b.jpg

and no, it is not just my interpretation regarding universal 100 octane fuel use by RAF FC; the available evidence, from numerous sources, points to universal 100 octane use by RAF FC during the battle.

I have repeatedly challenged the 100 octane fuel deniers to produce evidence for even a single RAF FC Hurricane or Spitfire 87 octane sortie during the BofB, and so far there's no takers.

It is like this Eugene: no 100 octane fuel, no 12lb boost.

So that must be why those in denial of 100 octane fuel use during the BoB can't name the 16 squadrons that they claim were the only squadrons to use 100 octane during the BoB.

However did the Bf110s and the few Bf109s use C3 fuel then?

S!

Well, Bf110C with DB601N engines/C3 and Bf109E-4/N using C3 are not modelled in game at the moment but no-one is complaining ;) Bf110C with 100oct would be easily faster than Hurricane and faster than Spit at some altitudes, but still no-one is whining for them, even they existed ;) Will be added if devs deem it OK based on data supplied to them. No need to make a drama out of it at all.

I flew red on ATAG and damn that Spitfire Mk.Ia 100oct and Spitfire Mk.II are easy to fly, even with slightest grasp of retaining E with proper maneuvers the Spits eat Bf109's for breakfast. The view out is best bar none and handling so forgiving, saw a lot of Bf109's spin out of the sky. Sure CEM caused a bit of problems for me but initial impression of Spitfire was pleasing. Sure maybe not up to speeds and all that but it can hold it's own easily with a competent pilot :)

Of course, they're German planes.

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