NZTyphoon Posted July 2, 2019 Posted July 2, 2019 The memo dated 18 September 1944 was written by A.D.G.B, and referred to the operational requirements of A.D.G.B aircraft - it did not apply to 2 TAF operations or aircraft. The memo clearly states: Quote iii) The increased performance available by the use of 150 is not an essential operational requirement for the role which A.D.G.B aircraft will be called to undertake in the near future. meaning that the V-1 threat had subsided and Luftwaffe fighters were as rare as hen's teeth over A.D.G.B's operational area: why bother using the fuel, when it could be better used by 2 TAF aircraft? By November 1944, the ADGB Spitfire XIV squadrons had been transferred to 2 TAF and 150 grade fuel had been cleared for operational use by all 2 TAF Spitfires, as noted in a November 1944 memo from SHAEF: http://www.wwiiaircraftperformance.org/150grade/150_Grade_20-11-44.jpg also note the final sentence: Quote ALL OF THE SQUADRONS CAN BE TAKEN AS OF 20 AIRCRAFT STRENGTH. Couldn't be any clearer, really. 1 2
HBPencil Posted July 2, 2019 Posted July 2, 2019 16 hours ago, Talon_ said: HEADQUARTERS: AIR DEFENCE GREAT BRITAIN. ROYAL AIR FORCE BENTLEY PRIORY STANMORE MIDDLESEX 18th September 1944. Use of 150 Grade Fuel Sir, I have the honor to refer to the above subject, and state that during the last 6 months a considerable amount of experience has been gained in A.D.G.B. with the use of 150 Grade Fuel in operational aircraft. The use of this fuel allowed higher boost pressures, which gave substantial increases in aircraft performance, and these increases were of great value when Squadrons of A.D.G.B. were employed against the flying bomb. Attached at Appendix “A” is a summary of the experience gained. 2. Because the flying bomb menace no longer exists, and because under existing operational commitments, aircraft of A.D.G.B. will have to refuel at landing grounds in Belgium or Holland, it has been decided to revert to the use of 130 Grade Fuel and to adjust engines to their previous maximum boost pressure. To continue to use 150 Grade Fuel in operational Squadrons is undesirable for the following reasons:- (i) The free interchange of Squadrons with T.A.F would be complicated in that aircraft would have to be modified for the lower boost pressure on transfer. (ii) To use 150 Grade Fuel when operating from U.K and to use 130 Grade Fuel when refueling on the Continent, would call for repeated adjustments of the maximum boost pressure obtainable. (iii) The increased performance obtainable by the use of 150 Grade Fuel is not an essential operational requirement for the role, which A.D.G.B. Squadrons will be called to undertake in the near future. (iv) The supply of 150 Grade Fuel is such that stocks can only be laid down a certain airfields. This imposes a degree of inflexibility, which is undesirable. (v) The use of high boost pressures in Mosquito aircraft calls for the fitting of open exhausts as the night flying exhausts will not withstand the temperatures associated with the higher boost pressures. Therefore, to continue to use the higher boost pressures in Mosquito aircraft makes the aircraft unsuitable for normal Night Fighter operation. The Air Officer Commanding-in – Chief, Headquarters Allied Expeditionary Air Force. Legit yet off topic question (rather like the whole 150oct 'discussion'), perhaps someone here can clear this up... I've seen this quoted a few times (don't recall ever seeing a link to the source though) but I've never seen an explanation as to why the AO-CIC AEF (AM Leigh-Mallory) was the one to write to "Sir" (Portal or Sinclair I assume) about a command that wasn't his? AM Roderic Hill being the CIC of ADGB/FC at that time. Or is it the other way around and it was Hill who wrote that letter and, for some reason, signed it AO-CIC HQ AEAF? Anyhow, back on topic, should the XIV be included? It's a 'yes' from me.
Talisman Posted July 2, 2019 Posted July 2, 2019 Griffon power 150 Octane grade fuel (official document): 18 lbs and 25 lbs boost performance (official document): Another official document regarding 150 Octane fuel and the Spitfire XIV: 1
PainGod85 Posted July 2, 2019 Posted July 2, 2019 I'm reasonably sure the Mk XIV's engine was only ever cleared for +21 lb as the one time they tested +25 lb, they totaled the engine within one flight.
NZTyphoon Posted July 2, 2019 Posted July 2, 2019 (edited) 4 hours ago, PainGod85 said: I'm reasonably sure the Mk XIV's engine was only ever cleared for +21 lb as the one time they tested +25 lb, they totaled the engine within one flight. Definitely; the +21 lbs boost was considered 'interim' http://www.spitfireperformance.com/125wing-replacement-aircraft.jpg but AFAIK +25 lbs was never used operationally. Interestingly, manuals for the both the Griffon 64 and 69 referred to +25 lbs being cleared for service use. 42 Maintenance Group, which was responsible for supplying fuel and ordnance to 2 TAF, confirmed that the changeover from 100/130 grade to 100/150 grade fuel would start from 15 December 1944. Edited July 2, 2019 by NZTyphoon add 42 Maintenance Group
PainGod85 Posted July 2, 2019 Posted July 2, 2019 (edited) Well, the XIV used the Griffon 65. What the 64 and 69 were ultimately cleared for is irrelevant regarding the 65's maximum boost. That said, I do believe the 65 would've been modified and strengthened in order to take +25 lb if the war hadn't ended before the issues were fixed. E: For reference. Quote 4.3 Spitfire XIV (Griffon 65) Spitfire R.B.176, as received from Squadron, was operating at +19 lb./sq.in. boost and 2,750 r.p.m. (Griffon 65; 5-bladed Rotol propeller). It had a circular external rear view mirror with hemispherical fairing; no ice-guard on the air intake; a whip type aerial behind the hood; a radio mast projecting from the lower surface of the wing forward of the starboard aileron; another mast set in a fairing under the fuselage; small type bulges over the 20 m.m. cannon and the cannon stubs faired; the machine gun ports in the leading edge sealed. The 30 gal. auxiliary fuel tank (slipper type) was removed for the purpose of the tests. The paintwork was in poor condition. Parts of the leading edge and inboard surfaces of the wings were very badly chipped and scored. The leading edge was stripped of paint and repainted. The rest of the aircraft was rubbed down only. The engine was then modified to give +25 lb./sq.in. boost and one flight was made. Only two level speed measurements were obtained, as the engine became suddenly rough after about two minutes of the high boost on each level. Subsequent inspection showed that a blow back had occurred, damaging the air intake. The reduction gear was also found to be cracked and no further tests could be made with this engine. Edited July 2, 2019 by PainGod85
NZTyphoon Posted July 3, 2019 Posted July 3, 2019 2 hours ago, PainGod85 said: Well, the XIV used the Griffon 65. What the 64 and 69 were ultimately cleared for is irrelevant regarding the 65's maximum boost. That said, I do believe the 65 would've been modified and strengthened in order to take +25 lb if the war hadn't ended before the issues were fixed. E: For reference. I included the Griffon 64/69 data more for interest than anything else, because, as you rightly point out, neither of them were used in the Spitfire XIV/XVIII/XIX family during wartime operations: they were, in effect modified and strengthened variants of the Griffon 61.
trista Posted July 3, 2019 Author Posted July 3, 2019 (edited) actually,xiv in fsx is 21 lb,this picture was caught at height around 1000+ m Edited July 17, 2019 by aft1983
1CGS LukeFF Posted July 4, 2019 1CGS Posted July 4, 2019 @aft1983, English is the spoken language of this part of the forum.
trista Posted July 5, 2019 Author Posted July 5, 2019 9 hours ago, PainGod85 said: But what does it say? mean they don't care about what we want,just like spitfire xiv
blockheadgreen_ Posted July 7, 2019 Posted July 7, 2019 There may have been variations in the upper cowling, as there are in Mk IXs and XVIs, but i think it's just a trick of the camera.
trista Posted July 8, 2019 Author Posted July 8, 2019 this unpainted xiv can be a model when 777 decide to make xiv
[-=BP=-]Slegawsky_VR Posted July 8, 2019 Posted July 8, 2019 On 7/6/2019 at 3:44 PM, aft1983 said: That was the best sounding spit, dug out this from the archives:
trista Posted July 9, 2019 Author Posted July 9, 2019 2 hours ago, Slegawsky said: That was the best sounding spit, dug out this from the archives: maybe, i think so
trista Posted July 9, 2019 Author Posted July 9, 2019 3 hours ago, Slegawsky said: That was the best sounding spit, dug out this from the archives: but xiv don't have its skin,and this picture isn't clear enough to according to 3 hours ago, Slegawsky said: That was the best sounding spit, dug out this from the archives: actually the plane in this picture isn't xiv, it is spitfire pr xix
JV69badatflyski Posted July 9, 2019 Posted July 9, 2019 (edited) error Edited July 9, 2019 by JV69badatflyski
II/JG17_HerrMurf Posted July 10, 2019 Posted July 10, 2019 30 minutes ago, aft1983 said: i think airfix model is real,777can make their xiv model according to airfix prxix's model Outside of the obvious copyright issues, BoX models are created from original documents.
blockheadgreen_ Posted July 10, 2019 Posted July 10, 2019 Frankly the F Mk 21 is more interesting to me; I know it's not really relevant to the timeline to be depicted (in-service late March, reached the continent only at the end of hostilities) but it just tickles my fancy somehow I can't explain it.
trista Posted July 10, 2019 Author Posted July 10, 2019 12 minutes ago, Lythronax said: Frankly the F Mk 21 is more interesting to me; I know it's not really relevant to the timeline to be depicted (in-service late March, reached the continent only at the end of hostilities) but it just tickles my fancy somehow I can't explain it. it has the same shape as the xiv
ZachariasX Posted July 10, 2019 Posted July 10, 2019 14 minutes ago, aft1983 said: it has the same shape as the xiv But a rather different airframe underneath it.
blockheadgreen_ Posted July 11, 2019 Posted July 11, 2019 On 7/10/2019 at 1:47 PM, aft1983 said: it has the same shape as the xiv Not quite, the airframe is broadly similar externally, but internally everything is revised and reinforced. Add to that the entirely different wings, it truly is a much more potent aircraft. Griffon Spitfires are a very confusing story. After the F Mk XII interim type with a single-stage Griffon, there were meant to be two "super-Spitfires": the F XVIII with the E wing (albeit with new stainless steel spars which allowed for higher VnE and greater stores capacity) and the Supermarine Victor F 21 (new names were discussed but eventually dropped), which was a revised version of the original fuselage with a wholly revised wing with extended tips and much larger tabbed ailerons (the tips were later clipped to the original span but unmodified in planform, which is why they look a bit blunted). The 21 was intended to arrive first (which it did) with the XVIII with a fail-safe in case the new wing was a flop. The XIV was in fact an offshoot of the Mk 21 project using the Mk VIII airframe, as an interim to get a two-stage Griffon "super-Spitfire" out as soon as possible for the invasion - but it ended up sticking just as the Mk V and IX did. Unfortunately it inherits the downsides of using an airframe specifically designed for the Merlin, unlike the XVIII and 21 which were purpose-built. 1 1
1CGS LukeFF Posted July 11, 2019 1CGS Posted July 11, 2019 2 hours ago, aft1983 said: this can be taken as a blueprint when 777 decide to make xiv for players 777 knows plenty well how to acquire good blueprints when modeling a new aircraft, but it certainly doesn't include all of these images that you've posted that have been flipped 180 degrees horizontally. 1
trista Posted July 11, 2019 Author Posted July 11, 2019 6 hours ago, LukeFF said: 777 knows plenty well how to acquire good blueprints when modeling a new aircraft, but it certainly doesn't include all of these images that you've posted that have been flipped 180 degrees horizontally. fine
ShadowStalker887 Posted July 15, 2019 Posted July 15, 2019 (edited) I'm really kind of want the Spitfire XIV and but I also kind of don't. I really want it because it's a beautiful aircraft and has very good performance..........but I also don't want it because it has better performance then my beloved Dora 9. And since I'm a campaign guy, the AI's super spotting abilities and terminator level of determination it will probably make it a colossal pain to fight......... Nethertheless it fits the timeframe, it's a beloved aircraft (therefore very marketable) and it will almost certainly make the game more fun so it gets my vote. Edited July 15, 2019 by ShadowStalker887 1
JonRedcorn Posted July 16, 2019 Posted July 16, 2019 18 hours ago, ShadowStalker887 said: You already posted that picture and I wonder why you quoted me while doing it.... 1
trista Posted July 16, 2019 Author Posted July 16, 2019 On 7/15/2019 at 11:28 PM, ShadowStalker887 said: You already posted that picture and I wonder why you quoted me while doing it.... It is a joke
Kurfurst Posted July 17, 2019 Posted July 17, 2019 Wow that last picture is fugly - probably the worst combination of color, variant (clipped) and shooting angle I have ever seen.
trista Posted July 17, 2019 Author Posted July 17, 2019 3 hours ago, VO101Kurfurst said: Wow that last picture is fugly - probably the worst combination of color, variant (clipped) and shooting angle I have ever seen. what about this one 1
ShadowStalker887 Posted July 17, 2019 Posted July 17, 2019 14 hours ago, aft1983 said: It is a joke Fair enough. Must've went over my head.
ZachariasX Posted July 18, 2019 Posted July 18, 2019 1 hour ago, aft1983 said: i like this skin Is there a particular reason why you keep posing mirrored images?
trista Posted July 18, 2019 Author Posted July 18, 2019 3 minutes ago, ZachariasX said: Is there a particular reason why you keep posing mirrored images? just i like this way
MiloMorai Posted July 18, 2019 Posted July 18, 2019 6 hours ago, ZachariasX said: Is there a particular reason why you keep posing mirrored images? He wants them to be shown 'coming' not 'going'. 1
trista Posted July 18, 2019 Author Posted July 18, 2019 46 minutes ago, MiloMorai said: He wants them to be shown 'coming' not 'going'. yes
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