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

[TomcatViP]

I am not sure it can works like that. For example I hve bought RoF with enthusiasm as soon as it was released and can't play it anymore.... There is no default FM left anywhere on any server !

[Al Schlageter]

The following Spitfire and Hurricane squadrons are known to have used 100 octane fuel before or during the BoB:
1, 17, 19, 41, 43, 54, 56, 64, 65, 66, 72, 73, 74, 79, 85, 87, 92, 141, 145, 151, 152, 222, 229, 234, 245, 249, 264, 303, 602, 603, 605, 609, 610, 611, 616

These squadrons were stationed at the following airfields (bold text) at sometime during the BoB.


11 Group

RAF Biggin Hill

- RAF West Malling

RAF Debden

- RAF Martlesham Heath

RAF Hornchurch

- RAF Hawkinge
- RAF Gravesend
- RAF Manston, night fighter base
- RAF Rochford

RAF Kenley

- RAF Croydon

RAF Northolt

RAF North Weald

- RAF Martlesham
- RAF Stapleford

RAF Tangmere

- RAF West Malling
- RAF Ford
- RAF Lee on Solent, RN airfield
- RAF Gosport, RN airfield
- RAF Thorney Island
- RAF Westhampnett


Not sure which Sector airfield these were assigned to but as all the sector airfields had 100 octane fuel, these to would need a stock of 100 octane fuel.

RAF Detling

RAF Eastchurch

RAF Hendon

RAF Lympne


In 10 Group, 5 of the 6 airfields had stocks of 100 octane fuel.

In 12 Group, 7 of the 8 airfields had stocks of 100 octane fuel.

In 13 Group, 7 of the 10 airfields had stocks of 100 octane fuel. Of the 3 that possible didn't have stocks of 100 octane fuel, one was based in the Shetland Is. and the other in the Orkney Is.

[winny]

Originally Posted by Al Schlageter

The following Spitfire and Hurricane squadrons are known to have used 100 octane fuel before or during the BoB:...

74 squadron were based at Hornchurch but flew (I think) to a forward Station (Manston) every day. You should maybe add that.

Good list

[Danelov]

74 squadron were based at Hornchurch but flew (I think) to a forward Station (Manston) every day. You should maybe add that.

Yes, same for the 54, Hornchurch was the normal base but the Squadron expended much of July using Rochford as base.

Yes, a good list. Not more mistery about this theme.

[Glider]

Originally Posted by Al Schlageter

The following Spitfire and Hurricane squadrons are known to have used 100 octane fuel before or during the BoB:
1, 17, 19, 41, 43, 54, 56, 64, 65, 66, 72, 73, 74, 79, 85, 87, 92, 141, 145, 151, 152, 222, 229, 234, 245, 249, 264, 303, 602, 603, 605, 609, 610, 611, 616

These squadrons were stationed at the following airfields (bold text) at sometime during the BoB.


11 Group

RAF Biggin Hill

- RAF West Malling

RAF Debden

- RAF Martlesham Heath

RAF Hornchurch

- RAF Hawkinge
- RAF Gravesend
- RAF Manston, night fighter base
- RAF Rochford

RAF Kenley

- RAF Croydon

RAF Northolt

RAF North Weald

- RAF Martlesham
- RAF Stapleford

RAF Tangmere

- RAF West Malling
- RAF Ford
- RAF Lee on Solent, RN airfield
- RAF Gosport, RN airfield
- RAF Thorney Island
- RAF Westhampnett


Not sure which Sector airfield these were assigned to but as all the sector airfields had 100 octane fuel, these to would need a stock of 100 octane fuel.

RAF Detling

RAF Eastchurch

RAF Hendon

RAF Lympne


In 10 Group, 5 of the 6 airfields had stocks of 100 octane fuel.

In 12 Group, 7 of the 8 airfields had stocks of 100 octane fuel.

In 13 Group, 7 of the 10 airfields had stocks of 100 octane fuel. Of the 3 that possible didn't have stocks of 100 octane fuel, one was based in the Shetland Is. and the other in the Orkney Is.

I did go to the NA today for a while to do some family history but did spent some time looking at a few of the squadron operational records. Once again I found that the details vary by squadron but can add two maybe three additional squadrons to the list of 100 Octane users.

No 111 squadron (based at Drem)
On the 15th February 1940 the squadron was released while the tanks were drained and replaced by 100 Octane.

No 32 Squadron (based Gravesend)
29th February 1940, 20 new type aircraft fitted with Metal Wings, new propellers and fuel were delivered during the month. 13 L type machines were flown away

No 213 Squadron
24th February new aircraft were delivered to the squadron.

As you can see, no 111 and 32 squadrons are pretty clear, but I have little doubt that no 213 squadron will be debated by some. My personal view is that if 32 squadron received new aircraft with all the improvements, its unlikely that 213 wouldn't less than a week earlier.

I did go to look up 232 squadron but they only formed in July 1940 when 100 Octane was the normal issue, so it wouldn't have been worth mentioning, i did look but there was no mention. I found it interesting that all the dates are in February.

[NZtyphoon]

Okay, how about some simple calculations?

Now, there is no doubt that 100 Octane fuel was available to Fighter Command before and during the Battle of Britain.

How Much? Woods and Dempster say 22,000 tons - which is too low.

http://www.ww2aircraft.net/forum/tec...b-16305-2.html

Mike Williams #26 scroll down to Table II Monthly Consumption of fuel & oil:

June - Aug 1940 = 10,000 tons consumed
Sept - = 14,000 tons consumed
Oct = 17,000 tons consumed

1 imperial gallon of 100 Octane = 7.1 pounds ("Oil" by D.J Peyton-Smith the official British war history on the oil and petroleum industry during WW2 page xvii "Note on Weights and Measures"):

1 ton of 100 octane = 2,240 lbs therefore 2,240 divided by 7.1 = 315.5 imp gal

Fuel Capacities:

Defiant I = 97 imp gal
Hurricane I = 90 imp gal
Spitfire I & II = 84 imp gal
TOTAL = 271 imp gal divide by 3 = average fighter fuel load = 90.3 imp gal (Defiant from memory, so feel free to correct me. Defiant II = 104 imp gal)

1 ton = 315.5 imp gal divided by 90.3 imp gal = 3.5 fuel loads (or sorties) per ton of 100 octane fuel. Assuming all aircraft emptied their tanks for each sortie, and assuming all aircraft shot down = 1 fuel load of 90.3 imp gal

NB: Not all aircraft returned with empty tanks and RAF policy was to refill each aircraft as soon as possible after landing, or each evening or early morning, to avoid vapour traps.

Blenheims were the only other aircraft known to have used 100 Octane fuel, albeit only in their outer wing fuel tanks, making things complicated for the poor pilots. (Warner, The Bristol Blenheim:A Complete History 2nd ed, page 100.)

Merlin III & XIIs could still use 87 octane fuel, hence training flights and other secondary flight duties, such as delivery, ferry flights, etc could use 87 octane fuel instead of 100.

June to August: 10,000 tons x 3.5 = 35,000 fuel loads
September: 14,000 tons x 3.5 = 49,000 fuel loads
October: 17,000 tons x 3.5 = 59,500 fuel loads

June to October = 41,000 tons x 3.5 = 143,500 fuel loads in 22 weeks = 6,523 fuel loads = 931.8 fuel loads per day

If Woods and Dempster 22,000 tons distributed (not consumed) between July and September = 77,000 fuel loads divided by 13 weeks = 5,923 fuel loads per week = 846 fuel loads daily.

The Battle of Britain by T.C.G. James shows 51,364 sorties, day & night from July 10 through Sept 30; some of the most intensive combat took place between these dates. Of course there were quiet periods when far fewer combat sorties were flown by Fighter Command; eg: August 16 & 17, between two days of intensive combat August 15 & 18.

51,364 divided by 13 weeks = 4,280 fuel loads = 611 fuel loads daily
average:

Hooton’s Eagle in Flames, Table 2, FC flew Sep 23-29: 4,825 defensive sorties Sep 30 – Oct 6: 1,782 defensive sorties, and yet consumption of 100 Octane was still increasing.

Been here before, unfortunately http://www.ww2aircraft.net/forum/avi...a-20108-7.html

[TomcatViP]

Originally Posted by NZtyphoon

Now, there is no doubt that 100 Octane fuel was available to Fighter Command before and during the Battle of Britain.

really ?

20000 post of the same "piece of evidence" does not makes it a demonstrated fact. We are still waiting for some cross references.

[41Sqn_Banks]

Originally Posted by TomcatViP

really ?

20000 post of the same "piece of evidence" does not makes it a demonstrated fact. We are still waiting for some cross references.

One combat report that shows the use of +12 boost (which requires 100 octane) is enough to proof that 100 octane was available. Of course it doesn't proof that it is available to all units, that's why NZtyphoon did the calculation.

[lane]

Originally Posted by 41Sqn_Banks

One combat report that shows the use of +12 boost (which requires 100 octane) is enough to proof that 100 octane was available.

Here's one!

[NZtyphoon]

100 Octane Fuel Consumed

July - Aug 1940 = 20,000 tons consumed
Sept - = 14,000 tons consumed
Oct = 17,000 tons consumed
Total = 51,000 tons of 100 octane fuel consumed
1 imperial gallon of 100 Octane = 7.1 pounds ("Oil" by D.J Peyton-Smith the official British war history on the oil and petroleum industry during WW2 page xvii "Note on Weights and Measures"):

1 ton of 100 octane = 2,240 lbs therefore 2,240 divided by 7.1 = 315.5 imp gal

Fuel Capacities:

Defiant I = 97 imp gal
Hurricane I = 90 imp gal
Spitfire I & II = 84 imp gal
Blenheim IV = 199 imp gal outer fuel tanks
TOTAL = 470 imp gal divide by 4 = average fighter/bomber fuel load = 117.5 imp gal (Defiant from memory, so feel free to correct me. Defiant II = 104 imp gal)

1 ton = 315.5 imp gal divided by 117.5 imp gal = 2.6 fuel loads (or sorties) per ton of 100 octane fuel.

*This is assuming all aircraft emptied their tanks for each sortie, and assuming all aircraft shot down = 1 fuel load of 90.3 imp gal

NB: Not all aircraft returned with empty tanks and RAF policy was to refill each aircraft as soon as possible after landing, or each evening or early morning, to avoid vapour traps.

Merlin III & XIIs could still use 87 octane fuel, hence training flights and other secondary flight duties, such as delivery, ferry flights, etc could still use 87 octane fuel

July to August: 20,000 tons x 2.6 = 52,000 sorties
September: 14,000 tons x 2.6 = 36,400 sorties
October: 17,000 tons x 3.5 = 44,200 sorties
Total July-October 132,600 fuel loads consumed or 132,600 sorties in which all aircraft landed with empty tanks.


The Battle of Britain by T.C.G. James shows 51,364 sorties, day & night from July 10 through Sept 30; some of the most intensive combat took place between these dates. Of course there were quiet periods when far fewer combat sorties were flown by Fighter Command; eg: August 16 & 17, between two days of intensive combat August 15 & 18.

Hooton’s Eagle in Flames, Table 2, FC flew Sep 23-29: 4,825 defensive sorties Sep 30 – Oct 6: 1,782 defensive sorties.

Total = 57,971 sorties yet

In spite of Blenheims being mixed in there are still 74,629 fuel loads available.

OR

Originally Posted by Kurfürst

And that is just that, about 1/3 to 1/2 the units

were using 100 octane fuel = 19,323 to 28,985 sorties, either that or the aircraft using 100 octane fuel carried out all the sorties, leaving the rest, who were confined to using 87 Octane, to do other things.

Originally Posted by Kurfürst

And that is just that, about 1/3 to 1/2 the units, so quite simply there's no factual basis, or evidence to, that all the others were using 100 octane. It's merely a wishful assumption.

132,600 sorties - 19,323 to 28,985 = 113,277 sorties or 103,615 sorties unaccounted for, including Blenheim sorties Where did all that fuel go?

The only engines cleared to use 100 Octane were the Merlin II III and XII and the Bristol Mercury XV, so it wasn't Bomber Command or Coastal Command who used it all, nor was it Army Co-Operation Command.