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

[28_Condor]

The writer Michael Korda, who served in the RAF, said in his latest book ("With Wings Like Eagles") that the RAF as a whole was served by american 100-octane fuel since 1939. And that was the advantage used against the German fighters that had fuel injection (but 87 octane fuel).

The British only really manufactured the fuel of 87 octane. It was Dowding who insisted that the British government to acquire the fuel from the Americans.

[Robo.]

According to some sources, the test certificate (this 'Page 40' document) is from testing of Merlin III improvements - of what has later become the Merlin XII. Unfortunately, without the rest of this paperwork (previous 39 pages) we can only assume what exactly is that all about I am afraid...

Anyway, knowing RR habit of testing and 'breaking' engines while improving parts that fail first to get more power, this makes perfect sense to me. Ratings of both Merlin XII and Merlin III are well documented and researched - Merlin in perspective pg. 155 and onwards states all ratings according to improvements along from III to XII:

R.M.1.S. (Merlin III)

combat power: 1310hp, 3000rpm, 9000ft., +12lbs
(combat power: 1440hp, 3000rpm, 5500ft., +16lbs - Sea Hurricane only)
take off: 880hp, 3000rpm, +6.25lbs.
cruising: 2600rpm, +4.5lbs.
climbing: 2600rpm, +6.5lbs.

R.M.2.S. (Merlin III, as R.M.1.S. but with increased take-off power on 100 octane fuel, superseded by the use of combat ratings on R.M.1.S.)

combat power: 1000hp, 3000rpm, 15500ft.,+6.25lbs.
take off: 1000hp, 3000rpm, +8.25lbs.
cruising: 2600rpm, +4.5lbs.
climbing: 2600rpm, +6.5lbs.

R.M.3.S. (as Merlin IV but higher supercharger gear ratio (note was 8.588 on Merlin III, is 9.089 on Merlin XII) and 100 octane fuel. For Spitfire II)

combat power: 1280hp, 3000rpm, 10500ft.,+12lbs.
take off: 1175hp, 3000rpm, +12.5lbs.
cruising: 2650rpm, +7bs.
climbing: 2850rpm, +9lbs.

R.M.4.S. was regarding further improvements on Merlin XII, but was never production type; superseded by Merlin 45

[Glider]

CRUMPP
Your reply doesn't give the additional pages of the pilots notes that would give some indication as to the type of Spitfire we are looking at.

Can you give us a link to the rest of the pilots notes so we can review them in detail. You will understand as the sheet from the pilots notes shown don't mention a date.

As I said if it doesn't mention the fuel then it almost certainly refer to an early version of the Spitfire. By June 1940 we know from combat and squadron records that 100 octane was in use and this would be reflected in the pilots notes.

One last thing, where do the pilots notes state 400 hp? or have we dropped that theory?

[Al Schlageter]

Glider, it is even less HP than that. Morgan and Shacklady in Spitfire: The History gives 990 hp for early Merlin engines. So that would be 330hp according to Eugene's generalization.

Eugene is a little short on specifics, isn't he? But that is understandable when a document shows a times 2.5 increase in hp over what he claims at a lower boost level. Until he comes up with specifics, it is only so much smelly shovel from him.

I have not seen anything that proves there were any more by September. What I have seen is misuse of information such as a single Inspection and Test certificate to build a case the entire RAF was using 100 octane or failure to explain an illogical use to reserve ratio.

So squadron log books and pilot reports are garbage. Sure.

Quite dodging the question. What are the squadron numbers for those 16 squadrons.

Fill in the blanks __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ .

[NZtyphoon]

Originally Posted by Al Schlageter

Until he comes up with specifics, it is only so much smelly shovel from him.



So squadron log books and pilot reports are garbage. Sure.

Quite dodging the question. What are the squadron numbers for those 16 squadrons.

Fill in the blanks __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ .

And while you're about it Crumpp,

* Please explain why the Merlin III was cleared to use +12lbs boost, and instructions were issued for all Merlin engines to be modified to use 100 octane fuel and +12lbs boost in November 1939? Please explain what "it is understood there are adequate reserves of [100 Octane] fuel for this purpose." means?

* Please explain why it was that several squadrons were using 100 Octane fuel in February 1940? Then explain when the RAF decided to restrict the fuel's use to operational trials. Properly documented, of course.

* Please provide documentation showing that the RAF was engaged in nothing more than "operational trials" from Feb - Sept 1940.

*Then explain why A.P1590B.J.2-W states that all production engines from March 1940 were fitted with the necessary modifications on the production line, contradicting your convoluted explanation that a limited number of Merlins might have been modified, based on a 4 to 1 head reserve?

* Please provide documentary evidence that a reserve of 4 heads to 1 was required by the RAF?

* Please explain why Hurricane squadrons based in France used 100 Octane fuel operationally during May 1940, when you insist the RAF needed to use 16 squadrons to engage in "operational trials" up to September.

* Then please explain why you now insist that no Spitfire Is used 100 octane fuel, based on a single, so far undated, set of pilot's notes, when there are squadron and combat reports clearly showing that emergency +12 lbs boost was used by Spitfire, Hurricane and Defiant units?

* Please explain the administrative and logistical arrangements FC put in place to ensure that only 16 squadrons were able to use 100 octane fuel.

* Please explain what happened to at least 52,000 tons of 100 octane fuel. Provide documentary evidence showing that the stuff was merely sent back to reserves, was stored, or rejected for use.

You have been asked several times to come up with some decent evidence to prove that your speculative spin is correct - instead all we have been treated to is your usual evasion and evidence avoidence. Please, stop wasting everybody's time, including your own.

[Glider]

Originally Posted by Al Schlageter

Glider, it is even less HP than that. Morgan and Shacklady in Spitfire: The History gives 990 hp for early Merlin engines. So that would be 330hp according to Eugene's generalization.

How foolish of me. I know that the Rolls Royce Eagle in WW1 was producing 300 hp, do you think that he is mixing up Eagle and Merlin?

[NZtyphoon]

Originally Posted by 28_Condor

The writer Michael Korda, who served in the RAF, said in his latest book ("With Wings Like Eagles") that the RAF as a whole was served by american 100-octane fuel since 1939. And that was the advantage used against the German fighters that had fuel injection (but 87 octane fuel).

The British only really manufactured the fuel of 87 octane. It was Dowding who insisted that the British government to acquire the fuel from the Americans.

The British were manufacturing the iso-octane needed to produce 100 Octane fuel at Heysham, Billingham and Stanlow in Britain, while there were other sources of 100 Octane fuel from the Dutch East Indies, Trinidad etc, mostly from the British Shell Company and Anglo-American Oil Co, so it's not correct to say that all 100 Octane fuel came from the United States. (see attachments)

For Crumpp's benefit: the Trimpell article states that by 31 July 1940 there were 384 Spitfires in 19 Squadrons using the fuel, as well as PR Spitfires -

* On 13 July the OOB's show 19 Spitfire squadrons; in addition there are 31 Hurricane squadrons and 2 Defiant.

Crumpp can sneer all he likes, but this alone scuppers his blind addiction to 16 fighter squadrons.

[Al Schlageter]

NZt, there is that river in Egypt called the da nile.

[Kwiatek]

I think some forgot about these:

Pilot's Notes. Spitfire I Aircraft. AP 1565.

Merlin III Engine limitation:

[NZtyphoon]

Originally Posted by Kwiatek

I think some forgot about these:

Pilot's Notes. Spitfire I Aircraft. AP 1565.

Merlin III Engine limitation:

If I read things rightly this is where we came in...about 94 pages ago! Really, this thread has run its course - if Crumpp wants to continue with his evidence avoidance, fact evasion, all round inability to respond to direct questions and general time wasting he can do so alone. I have far more important things to do with my life.

28_Condor; lane, aka Mike Williams has an excellent site here Well worth the time to go through.