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#111
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Seems pretty straightforward but I wouldn't call this a primary source. Do they list their references?
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#112
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Stop editorializing what you think Kurfurst is doing (Kurfurst is desperate, etc) it only serves to make you look petty, petulant, and juvenile. Indeed from reading your postings at ww2aircraft.net that is the conclusion to which I have come about your character. In any case, I'm still reading the two threads and have yet to come across any definitive proof that RAF aircraft were 100% equipped with 100 octane at all times. I'm willing to be persuaded but that has not yet occurred. |
#113
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Kurfurst,
Could you kindly post a link to this article written by the australian author directly? I have been waiting almost 2 weeks for my account at allaboutwarfare.com to be activated but it hasn't happened yet. |
#114
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Data of the Fiat G.50 Freccia.
Weight(MTOW): 2402 kg Empty weight: 1963 kg Max speed: 472 kph/5000m Cruise speed: 415 kph Range: 670km Ceiling: 10,700m Climb rate: 6000m in 7'30'' ,5000m in 6'3'' Weapons: 2x Breda SAFAT with 150 rounds p/gun Gunsight Type S.Giorgio at riflesione Ammo: Counter included in panel Fire system: Warning light, extintor at biossido di carbonio. Radio: ARC 1 Fuel: 260 l(provision for 52 l of aux fuel in a fuselage tank) Power: Engine Fiat A.74 RC, radial, 14 cylinders 740 HP in take off. 840 HP with 2400rpm at 4000m 879 HP with "+100"(WEP) Propeller: Hamilton Standard 3D-41-1, constant speed, passo variabile Misc: In panel/cockpit: Carburator heat switch, gear indicators, fire warning light, compressed air indicators, ammo counter, engine instruments, compass, cowling flaps selector, Flaps lever, parking brake lever. Other: The G.50 turn well to the right but less satisfactory to the left . Stall with 125 to 130 kph. Exit of stall with turn to the right. Dates from: "Fiat G.50 Le Macchine e la Storia, Stem Mucchi, Modena-Italia" Last edited by Danelov; 06-17-2011 at 07:17 AM. |
#115
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That's all I have for now.
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#116
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![]() ![]() While not definative it provides a date when the British public may have become aware of 100 octane |
#117
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And here is a site that discusses in length the benefits of the 109/Spit including pilot anidotes and references the introduction of 100 Hi-Octane fuel
http://www.spitfireperformance.com/spit1vrs109e.html And for those to lazy to read... The Merlin III engine data is from Rolls-Royce. 24 The DB 601A engine data is taken from curves found in the DB 601 A u. B Motoren-Handbuch of May 1942. 25 Trials were successfully carried out in October 1939 to increase the power of the Spitfire's Merlin II and III engines by raising the manifold pressure to +12 lbs./sq.in. 26 Air Ministry A.P.1590B/J.2-W. dated 20 March 1940 gives official notice that "The emergency use of higher boost pressures up to +12 lb./sq. in. is now permitted for short periods by operation of the modified boost control cut-out". 27 Also during February and March 1940 Spitfire and Hurricane Squadrons were converting their aircraft over to 100 octane fuel, which made possible an increase in engine power by raising the boost to +12 lb/sq.in.. 28a 28b 28c 28d 28e 28f 28g 28h 28i 28j 28k 28l 28m 28n 28o 28p 28q 28r 28s 28t Combat reports show that +12 lb boost was used by the Spitfire (and Hurricane) squadrons during their first combats with the Me 109 E in May 1940 while covering the Dunkirk evacuation. 29 30 Hurricane Squadrons based in France during May of 1940 were also employing +12 lbs/sq.in. boost in combat. 31 31b The first Spitfire into service was delivered to No. 19 Squadron at Duxford on 4 August 1938. The use of 100 octane fuel was approved for Spitfire Squadrons by 24 September 1938. 32 Fighter Command noted on 6 December 1938 that Duxford, Debden, Northholt and Digby had received 100 octane fuel. 32b As of December 1938 Nos. 19 and 66 were based at Duxford and were the only RAF units then equipped with Spitfires. The Air Ministry noted in a memo dated 12 December 1939 that "100 octane fuel is approved for use in Hurricane, Spitfire and Defiant aircraft, and state that issue will be made as soon as the fuel is available in bulk at the distribution depots serving the Fighter Stations concerned." 32c Gavin Bailey concluded that "The actual authorisation to change over to 100-octane came at the end of February 1940 and was made on the basis of the existing reserve and the estimated continuing rate of importation in the rest of the year." 33 As of 31 March 1940 220,000 tons of 100 octane fuel was held in stock. 34 The Co-ordination of Oil Policy Committee noted in the conclusions of their 18 May 1940 meeting with regard to the "Supply of 100 Octane fuel to Blenheim and Fighter Squadrons" that Spitfire and Hurricane units "had now been stocked with the necessary 100 octane fuel". 35 The Committee recorded that actual consumption of 100 octane for the 2nd Quarter 1940 was 18,100 tons. 36 Jeffrey Quill recalled: It was only shortly before the Battle of Britain that we changed over to 100 octane. It had the effect of increasing the combat rating of the Merlin from 3000 rpm at 6 1/2 lb boost (Merlin III) or 9 lb boost (Merlin XII) to 3,000 rpm at 12 lb boost. This, of course, had a significant effect upon the rate of climb, particularly as the constant speed propellers (also introduced just before the battle) ensured that 3,000 rpm was obtainable from the ground upwards whereas previously it was restricted by the two-pitch propellers. It also had an effect upon the maximum speed but this was not so significant as the effect upon rate of climb. 37 Wood and Dempster wrote in their book "The Narrow Margin": As it turned out, aviation spirit was to prove no worry for the R.A.F. By July 11th, 1940, the day after the Battle of Britain opened, stocks of 100 octane petrol used in the Merlin engine stood at 343,000 tons. On October 10th, twenty-one days before the battle closed, and after 22,000 tons had been issued, stocks had risen to 424,000 tons. With other grades of aviation spirit total stock available on October 10th, 1940, was 666,000 tons. Oil reserves were 34,000 tons. 38 Wood & Dempster’s figures for stocks of 100 octane are in agreement with those of the War Cabinet, however, their figure of 22,000 tons issued falls short of the Air Ministry’s figures as shown below. By 7 August 1940 "authority has been obtained for the use of 100 octane fuel in all operational aircraft and that instructions to that effect are being issued to Commands", i.e. all operational aircraft in Bomber, Coastal, Training and Fighter Commands. 39 On October 29, just before the end of the Battle of Britain, 423,400 tons of 100 octane fuel was in stock in the UK. 40a The War Cabinet recorded that 100 octane stocks stood at 202,000 tons on 31 December 1939 and that 100 octane stocks had risen to 499,000 tons one year later on 31 December 1940. 40b The Air Ministry recorded that 58,000 tons of 100 octane were issued during the Battle of Britain. 40c The War Cabinet recorded that 100 octane consumption within the UK for the whole of 1940 amounted to 130,000 tons, an average of 2,500 tons per week. 40d Consumption of 100 octane during the Battle of Britain averaged 10,000 tons per month for the months of July and August rising to 14,000 tons in September followed by 17,000 tons during October. Total consumption of 100 octane fuel during the Battle of Britain therefore was on the order of 50,000 tons. 40e V. A. Kalichevsky, author of the 1943 book The Amazing Petroleum Industry wrote: It is an established fact that a difference of only 13 points in octane number made possible the defeat of the Luftwaffe by the R.A.F. in the Fall of 1940. This difference, slight as it seems, is sufficient to give a plane the vital "edge" in altitude, rate of climb and maneuverability that spells the difference between defeat and victory. 40f The Spitfire I Pilot's Notes lays out the use of +12 boost as follows:41 An August 1, 1940 memo from Air Chief Marshall Dowding to all Fighter Groups shows that the pilots often exceeded these limits. The use of the automatic boost cut out control enables the pilot to get an emergency boost of + 12 lbs. per sq.in. from the engine for 5 minutes when circumstances demand it. Some pilots "pull the plug" with little excuse on every occasion. 42 Last edited by Bobb4; 06-17-2011 at 08:57 AM. |
#118
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Being serious for a moment, if you have any questions or explanations don't hesitate to ask either on the forum or by PM. That offer is obviously open to anyone. |
#119
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Maybe i missed something but why the debate on 100 octane at all, is there a quotable source that says it was not available?
Again all the sources I have found indicate it was, and ironically even during the Battle for France 12 lb boost was used an indication 100 Octane was available then? |
#120
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