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Quote:

Originally Posted by NZtyphoon (Post 399324)

According to Ted Hooton Spitfire Camouflage 1938-1940 Scale Aircraft Modelling Vol 5 No. 2, November 1982, the transition from Black/White under-surfaces to what was meant to be Sky (Type S) - there were some unit applied colours that were non standard - took place between 6 -17 June 1940 (p. 56).

R6692 - the Spitfire in the hanger, and the subject of the maintenance film, first flew June 3 was delivered to 6MU 5 June, then 609 Sqn. 7 June http://www.spitfires.ukf.net/p009.htm : in the film the aircraft code letter had yet to be applied, so the film was shot early-mid June, while it was still working into 609 Sqn. service. The 2nd photo of 609 Sqn Spitfires shows two of them still had black wheels, meaning they originally were painted black under the port wing, yet the undersurfaces of the wing were painted Sky, meaning the unit was in the middle of repainting its operational aircraft - again early - mid June 1940.

Thanks for the info NZtyphoon.

Here's a 602 Squadron Spitfire at Drem. Note the black & white undersides and the 100 octane label stenciled in white. This photo was taken during a press day, probably late February or March 1940. See also the Flight article from 28 March 1940 which describes 602 Squadron's operations using 100 octane fuel, probably the same event. (Ironically, for those that like to "get in the weeds" with this stuff, the author of the flight article was none other than H. F. King ;) ) 602 Squadron converted to 100 octane at Drem during February 1940.

http://www.spitfireperformance.com/6...-100octane.jpg

http://www.spitfireperformance.com/6...-100octane.jpg

As the Stations did have there own ORB, did anyone check them for entries concerning 100 octane fuel?

Quote:

Originally Posted by 41Sqn_Banks (Post 399512)

As the Stations did have there own ORB, did anyone check them for entries concerning 100 octane fuel?

I tried. The detail for each station varied, some did what you would expect as per the above, some only did entries for the station and ignored anything to do with the squadrons, and some were missing. Duxfords was missing two months of entries.

I also started to review the squadron records and what was interesting was that any squadron that formed after May 1940 had no mention of 100 octane at all and I checked these through to May 1941 by which time they certainly would have been using 100 octane. The inference I drew was that they didn't mention it as by then it was standard issue and therefore wouldn't be mentioned. This would support the view that the paper in May which referred to the stations concerned was talking about the Operational stations that had not been converted by April 1940.

I think its worth mentioning that Drem is in the North of Scotland. Not the first place I would issue 100 Octane too, if supply and distribution was to be limited.

It's interesting that so far ORB was found that mentions the switch to 100 octane fuel after May 1940. Of course some ORBs don't mention the switch at all. However if at least one squadron could be found it would clearly proof that it was not in use by all squadrons.

BTW: Anyone know what Merlin Modification 102 and 123 was? It was applied to the Spitfire of 41 Squadron in November 1939: http://www.oldrafrecords.com/records/424/4240052.gif

Also I remembered that there are two different Pilot's Notes for the Spitfire II are circulating, one that mentions the use of 100 octane only and another that mentions 100 octane (operational) and 87 octane (non-operational). Wouldn't it be logical that the first issue only contains 100 octane use as the new Spitfire II was only used operational at first, and only later when non-operational units used it the handling of 87 octane is mentioned.

Quote:

I think its worth mentioning that Drem is in the North of Scotland. Not the first place I would issue 100 Octane too, if supply and distribution was to be limited.

And the perfect place to conduct operational trials of a new fuel.

One of the things that greatly hampered the Luftwaffe was the inability to conduct operational testing outside of combat operations.

There was no place like Drem outside of the maelstrom of combat to collect operational data.

Quote:

Originally Posted by 41Sqn_Banks (Post 399525)

Also I remembered that there are two different Pilot's Notes for the Spitfire II are circulating, one that mentions the use of 100 octane only and another that mentions 100 octane (operational) and 87 octane (non-operational). Wouldn't it be logical that the first issue only contains 100 octane use as the new Spitfire II was only used operational at first, and only later when non-operational units used it the handling of 87 octane is mentioned.

Both are from June 1940 IIRC so any later amendments can be ruled out. In addition, Spitfire I pilot notes note 87 octane limits as well. I am haven't seen but its probably true for Hurricanes as well.

Quote:

Originally Posted by lane (Post 399500)

Here's a 602 Squadron Spitfire at Drem. Note the black & white undersides and the 100 octane label stenciled in white. This photo was taken during a press day, probably late February or March 1940.

Quite an unlikely date given that it seems the aircraft on the picture has armored glass and no Spitfires had any armor fitted until about June 1940.

Quote:

Originally Posted by Kurfürst (Post 399547)

Quite an unlikely date given that it seems the aircraft on the picture has armored glass and no Spitfires had any armor fitted until about June 1940.

Improved windshields were fitted regardles of the rest of the armor before June 1940.

Quote:

Originally Posted by 41Sqn_Banks (Post 399525)

<...> BTW: Anyone know what Merlin Modification 102 and 123 was? <...>

Hi 41Sqn_Banks,

Merlin/102: To make provision for increased ratio starter gearing the slipping torque of the starter clutch has been increased by extra spring pressure.

Merlin/123: Introduction of epicyclic type of starter motor gears having a 94.6 to 1 turning ratio.

A bit off topic but flip back one page in your 41 Sqdn ORB and check out Spitfire Alteration 1/36 - Armour Plating ;)

http://www.spitfireperformance.com/4...v39-armour.jpg

The Spit II was introduced in august in OTU.

Regarding the armoured windshield I hd the same remark as KF looking at the picture... weird.

Spit II was introduced a bit latter during BoB. Link Alrdy posted on ATAG

http://plane-crazy.purplecloud.net/A...e%20mk%202.htm