Inaccurate performance data for BOB fighters in COD comparing to RL data

[Seadog]

Originally Posted by Glider

On the contrary there are a number of papers, book, both technical and historical that mention that the RAF was equipped with 100 Octane for the BOB.

However There is nothing published anywhere that says that there was a fuel shortage, that they were forced to use 87 octane on operaions. All Kurfurst has posted is a pre war paper that said 18 squadrons of fighters and 2 squadrons of twin engined bombers. Plus an unsubstantiated posting from an Australian which
a) is riddled with errors.
b) is not supported by anything
c) that no one (not even Kurfurst) has seen
d) whee the archives that are supposed to hold it do not recognise.


Now the point of this was to ensure the people who are involved in the coding of the flight simulation were aware that if they followed the ideas put forward by Kurfurst were leaving themselves wide open for adverse comments.

I believe the case put foward for the use of 100 Octane in FC by all the units is a strong case, not perfect but strong.

We have
a) the pre war intention, of 18 + 2 squadrons
b) the preparation in Dec 1939 for the issues to the FC command stations in two stages initially the First Instance (covering all the Operational Bases and those that were identified at that time that would become operational) and the second tranch (The Non Operational bases). This paper outlines the conditions to be met (stocks to be in place) before it can be used.
c) the request from the Chief of the Air Staff simple and without limitation for fighter units and Blenheim units to start using the 100 Octane. The Chief of the Air Staff doesn't ask permission from the Oil Committee which is headed up by a senior but junior to him Air Force Officer. In the the British Armed Forces orders from senior officers were and are still today, requests.
d) The Oil Committee getting this underway. The Magic 'Certain' word comes up at this stage. Do I wish he hadn't written certain, of course, but I believe that it will refer to the first instance i.e. the operational stations not all the stations in Fighter Command. But Please note, I knew that information would casue confusion and I could have left it out, but I didn't I gave all the information that I had to the forum.
d) A very clear path that shows without any ambiguity that all Blenheim units in No 2 Group had 100 Octane
e) Confusion in Fighter Command about the changes needed and the sorting out of those questions (Mr Tweedie)
f) The completion of the task by the oil committee and the note of thanks on the job done.

Note that was all done by May. Even if there was a slight delay the BOB didn't start in anger until a few months later so time was on their side.

g) Finally we have in August permission given to use 100 Octane in all the commands.

All the above supported by consumption details, stock supplies, a good cross section of squadron notes, station notes and other documentation.

As I said earlier, is it a perfect case no, but its a strong one with a lot of documentation to support it.

What documentation have you got to say that 87 Octane was used in Operational missions during the BOB. None.

Some people doubt that all units didn't have 100 octane, so prove it, find any book, any article, any pilots notes or other station record that says that.

I will review Pps posting again with supporting docs as that seems to be key to the anti 100 Octane Brigade and then leave you to it. I can add nothing more.

I completely agree with you.

[winny]

I think there's a way to prove the majority of bases were converted, but it'll be time consuming.

Cross reference the combat reports from the battle mentioning 12lb boost, with the squadron involved, to the movements of that squadron for that date. ie. where were they, a: stationed? and b: where they scrambled from? (not always the same station).

In the past I counted at least 30 squadrons refering to 12lb boost in combat reports between May - July 1940.. That's nearly half of all FC's squadrons.
Add that to the fact that there were only around 30-32 'operational' stations being used at the time, and the rotation system, it would suggest widespread use of 100 octane.


Also does anyone know if you could actually run a converted Merlin on 87 oct?

If it was a case of just swithcing fuels then why the modification to the engine?

[Glider]

Originally Posted by winny

I think there's a way to prove the majority of bases were converted, but it'll be time consuming.

Cross reference the combat reports from the battle mentioning 12lb boost, with the squadron involved, to the movements of that squadron for that date. ie. where were they, a: stationed? and b: where they scrambled from? (not always the same station).

In the past I counted at least 30 squadrons refering to 12lb boost in combat reports between May - July 1940.. That's nearly half of all FC's squadrons.
Add that to the fact that there were only around 30-32 'operational' stations being used at the time, and the rotation system, it would suggest widespread use of 100 octane.


Also does anyone know if you could actually run a converted Merlin on 87 oct?

If it was a case of just swithcing fuels then why the modification to the engine?

Only a selection of squadrons were looked into so before you do this you would have to check every squadrons papers. You would also have to check every station for the fuel, a huge operation.
This is why I call the case a strong case but not a perfect case. The case for the limited use of 87 octane isn't supported by anything, making it a very weak case. They only have Pips posting which I have challenged with supporting documentation.
I would suggest that those who believe in the limited use of 100 octane should be asked to support that view. If they believe that Pips posting is the correct version of events then they need to support it and disprove the original documents that have been posted.

A converted Merlin could run on 87 octane but the performance would obviously be less. In a similar manner, a non converted merlin would run on 100 octane, but to get the performance gain, you need the fuel and the conversion