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#11
August 21st 03, 12:04 PM
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In article , Guy Alcala
writes I'll disagree here. You want two pilots so they can take turns flying tight formation. For night ops it was no big deal to put the a/c on george and have the first and second pilots swap out (before they replaced the 2nd pilot with a FE). That's not an option when flying in a combat box. With only a single pilot the formations are going to be looser, and that's the last thing the Brit heavies need, as they're already going to be the ground bait. Hmmm, we're assuming here that tight combat boxes are the only way to go. Whilst I haven't looked at it in depth, I reckon that with sufficient long range fighter escort, smaller, loser formations might have worked out fine. The combat box seems to me to make a large target for flak. Once air superiority is won and the invasion has happened it's not as big a deal, becaue there's less need to fly tight formation for as long, but we're talking about the period before that occurs. Both Lanc and Halifax have FE seats next to (and slightly aft) of the pilot, so the space shouldn't be a too much of a problem. Space may not have been a problem, but the FE seats (certainly on the Lanc, not sure about the Halifax) were fold out types to allow for the bomb aimer to take up his station. I remember reading reports that some bomb aimer's were able to crawl under the seat whilst the FE occupied it, but on the whole it sounds a difficult manoeuvre. The only recommended escape route (apart from the rear gunners station) was through the bomb aimer's hatch, getting the crew out with the 2nd pilot in his seat would be a major problem. In the Halifax, the pilot sat above the radio operator, I think with a walkway down the right hand side (level with the radio ops floor), not sure where/how the FEs seat was arranged (looks to me like he'd be hanging in mid-air if sat next to the pilot!). I wasn't aware that these two a/c had provisions for dual controls built in, although I knew that some had them; when we were trying to figure out what mods we'd have to make to run these a/c by day, we had allowed a fair amount of time to design and develop a production dual control system, so it seems that we were overcautious in estimating how much time that would take. The dual controls available were very crude connections to the existing controls. For operational use these may require re-working (along with the addition of a better 2nd seat and harness). Whether a 2nd pilot was required for daylight ops might be irrelevant, whether the command would agree to it is another question (all resources were tight). The BBMF Lanc has proper dual controls and two pilots. -- John 
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#12
August 21st 03, 09:52 PM
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The Revolution Will Not Be Televised wrote:
On Thu, 21 Aug 2003 06:53:31 GMT, Air Commodore Guy Alcala, Director of Fighter OperationsGuy Alcala wrote: Isn't rapid promotion in wartime wonderful? And to think, I was just a lowly Wing Commander on Butch's staff a month or so ago, along with then Group Captain Stickney. I'm still the only one of the three of us to appoint himself to the Air Council, so start bribing me now if you want me to rubber-stamp your promotion to Air rank. At the rate you're going I'd better begin, before you retire and take over from Freeman at MAP. I shall miss your sagacity, judiciousness, dare I say genius, that has made my own job immeasurably easier. The country owes you a debt of gratitude that it can never repay. I remain, Sir, your most humble and obedient servant. P.S. Are the rumors correct that AM Hill is going to be promoted from AOC 12 Group to AOCinC ADGB, about mid-November? 12 Group will have to be the base for our long-range escort force, so we'll need an AOC there who's fully committed to making long-range escort a reality. snip internal tank capacity [snip next test report] Now, was that 110 gallons a misprint, Nope, you've now moved onto the next tankage problem: the wing tanks! Notice how I've been using a figure of 12.5 Imperial gallons for them? Well, their size seems to fluctuate from 12.5 galls up to 16-or even 18 in some later Spits. 12.5 seems to be the most common as this report bears out: 85 galls forward fuselage plus two 12.5 galls in the wing giving 110 gallons. I've seen a precise figure of 13 point (something) given for the Mk. VII/VIII, which often gets rounded up to 14 gallons, although rounding to 27 total is closer. a rough rounding (seems unlikely), representative of the "standard" production a/c (details of differences not given) as opposed to the "non-standard" RB. 141, or just Supermarine fitting in whatever tanks they happened to have on the shelf on any particular day? My impression, and it isn't any more than that, but it is nonetheless based on some limited research on 125 Wing which fielded the first Spit XIV sqns in 2 TAF, is that 110 is representative of the RB-serials delivered in late '43 and early '44. Fine by me. The Mk. XIVs are for the continent anyway, as that 110 gives them about the same range as the Mk. IX, but less endurance. Note that the FR XIVs, with cameras in place of one of the RF tanks, still had the second 33 gallon tank. I think RF-tanked Mk XIVs can't be dismissed out of hand. But one maniacal idea at a time. Brng it up again and it's off to Wandsworth with you, for sabotaging the war effort. Listen, I'm all for your LR VIIIs, and I'm even helping by pushing for rear-fuselage tanks for them, but the quid pro quo is XIV production beginning on schedule, and the fitting of rear tanks to them whenever possible. Whenever possible is fine, as long as it doesn't delay our increasing standard Mk. VIII production. snip unfortunate but seemingly unavoidable areas of agreement The PN's for the VIII give an allowance of 9 gallons for run-up and take-off. That should be out of the rear tank. Depends. For safety reasons it's more likely to be from one of the main tanks, so as to avoid any fumbling during takeoff if there are feed problems. I've just been thinking of this. Why not run the rear tank via a pump (or two for redundancy) to the main tanks to keep them full while running down the rear tank, just like the approach with the wing tanks? The one account I have of the L.e. tank usage says that they are transferred to the main(s) once space is available. Otherwise, the excess gets vented overboard, which is rather counterproductive. snip musings on tank plumbing I imagine the rest of the profile would be flown at a low-revs, high-boost weak mixture cruise. That could go down to 1,800 rpm, but then there's the tactical need to maintain a high airspeed. I suggest your wing commanders cruisie at 2,200 rpm and +4 boost, for a consumption of 61 gallons per hour. That should give about 6.5 air mpg, or maybe 6 when the drag of the external tank is taken into consideration. What kind of air speed does that give you? 180 IAS according to the (rather small-scale) graph at 15,000 feet. It claims to be valid from 10,000-25,000 feet, but not fully accurate for rpm at different heights. Zemke says that they normally cruised at maybe 210-220 IAS on Rodeos (doesn't say specifically what the cruise was on Ramrods), giving 320-325 TAS at escort altitudes. By November 1942 the Spit Vs at least seem to be cruising at 300mph TAS at 20,000 feet when anticipating enemy contact. 2,400 rpm +4 lbs seems to have been one target setting recorded in some primary documentation I've seen from that time. 2,400 rpm at +4lbs would increase consumption to 66 galls per hour, but should permit (according to the graph) 200 IAS within the acceptable revs range. The Air mpg drops to 6, and we'd need to increase that consumption for external tank drag, but it doesn't change things much. The relatively low consumption of the Merlin seems to stand it in good stead there, but I've always thought the P-47 cruised faster. I'd think 200 IAS cruise at escort height would be about the minimum we'd want over the continent. 200 IAS @ 25kft gets us 300 TAS, @ 30kft 327 TAS, ignoring P.E. and C.E. in both cases. snip even more general agreement Some IXs did get it, but I can't discover the logic or process involved at this stage. I increasingly wonder if it was a matter of "whatever the subcontractors deliver today." Any idea who made the internal tanks (if not Supermarine), and if there was more than one company involved? Yes, there were several firms involved, some locally around Southampton. I think CBAF made their own. I don't want to investigate that nightmare much further. snip Oh, admit it, you enjoy hunting through boxes of stuff at the PRO, peering at miniscule type on yellowed, 50+ year old mimeographed copies so you can discover that a/c in serial range XX-1XX through XX-127 were fitted with canopy enmergency release pin 2C-5392-9 rather 2C-5587-6, owing to the delivery van breaking down. No, but the service acceptances by the RAF seem to be (by a hand and eye count of the appendices in Shacklady & Morgan, so I can't claim any real authority for these figures) about 90 in July 1943, 98 in October, declining to 67 in November, 53 in December and 28 in January 1944. This doesn't reflect production figures per se, as the aircraft had often been in storage for some time or were shipped to Casablanca or India, and had actually been produced earlier. But it does give an indicator of deliveries, which is almost what you want. We're in fat city, then, and I see no need to mess around with Mk. Vs. This is where my political considerations kick in: the promises to the DAF, the 12th AF and the Russians and the Far East already exist and need to be serviced. Almost all the VIIIs being produced are being shipped out to overseas theatres. Which is why we'll replace them with Mk. IXs temporarily (Mk. VC Trops to the Far East if we don't have enough Mk. IXs), until we can ramp up production. If you want the whole of Mk VIII production, when does this decision get made? End of September '43 seems like a good date, and continuing for the next few months. My Mk V speculation was based on what would be likely with existing resources. 12 Group needed that range, and FC didn't give a stuff what they did with their Mk Vs (e.g. the LF Vb conversions at this time). Increasing internal tankage would be a small step to them, without major political considerations. I can only see this whole scenario working if FC actually have some resources capable of supporting a daylight effort; even the CAS can't complelely dictate operational tactics to an RAF C-in-C. We'll have to wait on AVM Stickney's Cg calcs, I think. Mk. VIII production rate Seems reasonable, although we'd want to boost Mk. VIII production well above 90/month, I'd agree, but frankly you're hitting the limit of the relevant production resource, i.e. the Hampshire production group focused on Supermarine's dispersed work. You might get 120 or so out of them per month of they packed up everything else, bar a couple of PR Spits and the beginnings of the Mk XIV. The next focus I suggest would be getting Westlands, finishing off their Mk V production run with Seafires to move to Mk VIIIs while tackling Castle Bromwich. I think you could fully convert to Mk VIII-based production by spring 1944, with an increasing number of rear-tank versions available within that output, and with the Mk XIV entering service at the same time. snip Sounds like the way to go. I'm not sure that we even need Castle Bromwich to transition. If we can get say 150-200 Mk. VIIIs a month, that will probably do the trick until we're on the continent and/or get our Mustangs. By all means, though, let's make sure we get at least 96 gallons in the Mk. IXs from now on. It's ridiculous to be building a/c with 85. Guy
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#13
August 21st 03, 09:52 PM
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The Revolution Will Not Be Televised wrote:
On Thu, 21 Aug 2003 06:53:31 GMT, Air Commodore Guy Alcala, Director of Fighter OperationsGuy Alcala wrote: Isn't rapid promotion in wartime wonderful? And to think, I was just a lowly Wing Commander on Butch's staff a month or so ago, along with then Group Captain Stickney. I'm still the only one of the three of us to appoint himself to the Air Council, so start bribing me now if you want me to rubber-stamp your promotion to Air rank. At the rate you're going I'd better begin, before you retire and take over from Freeman at MAP. I shall miss your sagacity, judiciousness, dare I say genius, that has made my own job immeasurably easier. The country owes you a debt of gratitude that it can never repay. I remain, Sir, your most humble and obedient servant. P.S. Are the rumors correct that AM Hill is going to be promoted from AOC 12 Group to AOCinC ADGB, about mid-November? 12 Group will have to be the base for our long-range escort force, so we'll need an AOC there who's fully committed to making long-range escort a reality. snip internal tank capacity [snip next test report] Now, was that 110 gallons a misprint, Nope, you've now moved onto the next tankage problem: the wing tanks! Notice how I've been using a figure of 12.5 Imperial gallons for them? Well, their size seems to fluctuate from 12.5 galls up to 16-or even 18 in some later Spits. 12.5 seems to be the most common as this report bears out: 85 galls forward fuselage plus two 12.5 galls in the wing giving 110 gallons. I've seen a precise figure of 13 point (something) given for the Mk. VII/VIII, which often gets rounded up to 14 gallons, although rounding to 27 total is closer. a rough rounding (seems unlikely), representative of the "standard" production a/c (details of differences not given) as opposed to the "non-standard" RB. 141, or just Supermarine fitting in whatever tanks they happened to have on the shelf on any particular day? My impression, and it isn't any more than that, but it is nonetheless based on some limited research on 125 Wing which fielded the first Spit XIV sqns in 2 TAF, is that 110 is representative of the RB-serials delivered in late '43 and early '44. Fine by me. The Mk. XIVs are for the continent anyway, as that 110 gives them about the same range as the Mk. IX, but less endurance. Note that the FR XIVs, with cameras in place of one of the RF tanks, still had the second 33 gallon tank. I think RF-tanked Mk XIVs can't be dismissed out of hand. But one maniacal idea at a time. Brng it up again and it's off to Wandsworth with you, for sabotaging the war effort. Listen, I'm all for your LR VIIIs, and I'm even helping by pushing for rear-fuselage tanks for them, but the quid pro quo is XIV production beginning on schedule, and the fitting of rear tanks to them whenever possible. Whenever possible is fine, as long as it doesn't delay our increasing standard Mk. VIII production. snip unfortunate but seemingly unavoidable areas of agreement The PN's for the VIII give an allowance of 9 gallons for run-up and take-off. That should be out of the rear tank. Depends. For safety reasons it's more likely to be from one of the main tanks, so as to avoid any fumbling during takeoff if there are feed problems. I've just been thinking of this. Why not run the rear tank via a pump (or two for redundancy) to the main tanks to keep them full while running down the rear tank, just like the approach with the wing tanks? The one account I have of the L.e. tank usage says that they are transferred to the main(s) once space is available. Otherwise, the excess gets vented overboard, which is rather counterproductive. snip musings on tank plumbing I imagine the rest of the profile would be flown at a low-revs, high-boost weak mixture cruise. That could go down to 1,800 rpm, but then there's the tactical need to maintain a high airspeed. I suggest your wing commanders cruisie at 2,200 rpm and +4 boost, for a consumption of 61 gallons per hour. That should give about 6.5 air mpg, or maybe 6 when the drag of the external tank is taken into consideration. What kind of air speed does that give you? 180 IAS according to the (rather small-scale) graph at 15,000 feet. It claims to be valid from 10,000-25,000 feet, but not fully accurate for rpm at different heights. Zemke says that they normally cruised at maybe 210-220 IAS on Rodeos (doesn't say specifically what the cruise was on Ramrods), giving 320-325 TAS at escort altitudes. By November 1942 the Spit Vs at least seem to be cruising at 300mph TAS at 20,000 feet when anticipating enemy contact. 2,400 rpm +4 lbs seems to have been one target setting recorded in some primary documentation I've seen from that time. 2,400 rpm at +4lbs would increase consumption to 66 galls per hour, but should permit (according to the graph) 200 IAS within the acceptable revs range. The Air mpg drops to 6, and we'd need to increase that consumption for external tank drag, but it doesn't change things much. The relatively low consumption of the Merlin seems to stand it in good stead there, but I've always thought the P-47 cruised faster. I'd think 200 IAS cruise at escort height would be about the minimum we'd want over the continent. 200 IAS @ 25kft gets us 300 TAS, @ 30kft 327 TAS, ignoring P.E. and C.E. in both cases. snip even more general agreement Some IXs did get it, but I can't discover the logic or process involved at this stage. I increasingly wonder if it was a matter of "whatever the subcontractors deliver today." Any idea who made the internal tanks (if not Supermarine), and if there was more than one company involved? Yes, there were several firms involved, some locally around Southampton. I think CBAF made their own. I don't want to investigate that nightmare much further. snip Oh, admit it, you enjoy hunting through boxes of stuff at the PRO, peering at miniscule type on yellowed, 50+ year old mimeographed copies so you can discover that a/c in serial range XX-1XX through XX-127 were fitted with canopy enmergency release pin 2C-5392-9 rather 2C-5587-6, owing to the delivery van breaking down. No, but the service acceptances by the RAF seem to be (by a hand and eye count of the appendices in Shacklady & Morgan, so I can't claim any real authority for these figures) about 90 in July 1943, 98 in October, declining to 67 in November, 53 in December and 28 in January 1944. This doesn't reflect production figures per se, as the aircraft had often been in storage for some time or were shipped to Casablanca or India, and had actually been produced earlier. But it does give an indicator of deliveries, which is almost what you want. We're in fat city, then, and I see no need to mess around with Mk. Vs. This is where my political considerations kick in: the promises to the DAF, the 12th AF and the Russians and the Far East already exist and need to be serviced. Almost all the VIIIs being produced are being shipped out to overseas theatres. Which is why we'll replace them with Mk. IXs temporarily (Mk. VC Trops to the Far East if we don't have enough Mk. IXs), until we can ramp up production. If you want the whole of Mk VIII production, when does this decision get made? End of September '43 seems like a good date, and continuing for the next few months. My Mk V speculation was based on what would be likely with existing resources. 12 Group needed that range, and FC didn't give a stuff what they did with their Mk Vs (e.g. the LF Vb conversions at this time). Increasing internal tankage would be a small step to them, without major political considerations. I can only see this whole scenario working if FC actually have some resources capable of supporting a daylight effort; even the CAS can't complelely dictate operational tactics to an RAF C-in-C. We'll have to wait on AVM Stickney's Cg calcs, I think. Mk. VIII production rate Seems reasonable, although we'd want to boost Mk. VIII production well above 90/month, I'd agree, but frankly you're hitting the limit of the relevant production resource, i.e. the Hampshire production group focused on Supermarine's dispersed work. You might get 120 or so out of them per month of they packed up everything else, bar a couple of PR Spits and the beginnings of the Mk XIV. The next focus I suggest would be getting Westlands, finishing off their Mk V production run with Seafires to move to Mk VIIIs while tackling Castle Bromwich. I think you could fully convert to Mk VIII-based production by spring 1944, with an increasing number of rear-tank versions available within that output, and with the Mk XIV entering service at the same time. snip Sounds like the way to go. I'm not sure that we even need Castle Bromwich to transition. If we can get say 150-200 Mk. VIIIs a month, that will probably do the trick until we're on the continent and/or get our Mustangs. By all means, though, let's make sure we get at least 96 gallons in the Mk. IXs from now on. It's ridiculous to be building a/c with 85. Guy
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#14
August 21st 03, 09:53 PM
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The Revolution Will Not Be Televised wrote:
On Thu, 21 Aug 2003 06:53:31 GMT, Air Commodore Guy Alcala, Director of Fighter OperationsGuy Alcala wrote: Isn't rapid promotion in wartime wonderful? And to think, I was just a lowly Wing Commander on Butch's staff a month or so ago, along with then Group Captain Stickney. I'm still the only one of the three of us to appoint himself to the Air Council, so start bribing me now if you want me to rubber-stamp your promotion to Air rank. At the rate you're going I'd better begin, before you retire and take over from Freeman at MAP. I shall miss your sagacity, judiciousness, dare I say genius, that has made my own job immeasurably easier. The country owes you a debt of gratitude that it can never repay. I remain, Sir, your most humble and obedient servant. P.S. Are the rumors correct that AM Hill is going to be promoted from AOC 12 Group to AOCinC ADGB, about mid-November? 12 Group will have to be the base for our long-range escort force, so we'll need an AOC there who's fully committed to making long-range escort a reality. snip internal tank capacity [snip next test report] Now, was that 110 gallons a misprint, Nope, you've now moved onto the next tankage problem: the wing tanks! Notice how I've been using a figure of 12.5 Imperial gallons for them? Well, their size seems to fluctuate from 12.5 galls up to 16-or even 18 in some later Spits. 12.5 seems to be the most common as this report bears out: 85 galls forward fuselage plus two 12.5 galls in the wing giving 110 gallons. I've seen a precise figure of 13 point (something) given for the Mk. VII/VIII, which often gets rounded up to 14 gallons, although rounding to 27 total is closer. a rough rounding (seems unlikely), representative of the "standard" production a/c (details of differences not given) as opposed to the "non-standard" RB. 141, or just Supermarine fitting in whatever tanks they happened to have on the shelf on any particular day? My impression, and it isn't any more than that, but it is nonetheless based on some limited research on 125 Wing which fielded the first Spit XIV sqns in 2 TAF, is that 110 is representative of the RB-serials delivered in late '43 and early '44. Fine by me. The Mk. XIVs are for the continent anyway, as that 110 gives them about the same range as the Mk. IX, but less endurance. Note that the FR XIVs, with cameras in place of one of the RF tanks, still had the second 33 gallon tank. I think RF-tanked Mk XIVs can't be dismissed out of hand. But one maniacal idea at a time. Brng it up again and it's off to Wandsworth with you, for sabotaging the war effort. Listen, I'm all for your LR VIIIs, and I'm even helping by pushing for rear-fuselage tanks for them, but the quid pro quo is XIV production beginning on schedule, and the fitting of rear tanks to them whenever possible. Whenever possible is fine, as long as it doesn't delay our increasing standard Mk. VIII production. snip unfortunate but seemingly unavoidable areas of agreement The PN's for the VIII give an allowance of 9 gallons for run-up and take-off. That should be out of the rear tank. Depends. For safety reasons it's more likely to be from one of the main tanks, so as to avoid any fumbling during takeoff if there are feed problems. I've just been thinking of this. Why not run the rear tank via a pump (or two for redundancy) to the main tanks to keep them full while running down the rear tank, just like the approach with the wing tanks? The one account I have of the L.e. tank usage says that they are transferred to the main(s) once space is available. Otherwise, the excess gets vented overboard, which is rather counterproductive. snip musings on tank plumbing I imagine the rest of the profile would be flown at a low-revs, high-boost weak mixture cruise. That could go down to 1,800 rpm, but then there's the tactical need to maintain a high airspeed. I suggest your wing commanders cruisie at 2,200 rpm and +4 boost, for a consumption of 61 gallons per hour. That should give about 6.5 air mpg, or maybe 6 when the drag of the external tank is taken into consideration. What kind of air speed does that give you? 180 IAS according to the (rather small-scale) graph at 15,000 feet. It claims to be valid from 10,000-25,000 feet, but not fully accurate for rpm at different heights. Zemke says that they normally cruised at maybe 210-220 IAS on Rodeos (doesn't say specifically what the cruise was on Ramrods), giving 320-325 TAS at escort altitudes. By November 1942 the Spit Vs at least seem to be cruising at 300mph TAS at 20,000 feet when anticipating enemy contact. 2,400 rpm +4 lbs seems to have been one target setting recorded in some primary documentation I've seen from that time. 2,400 rpm at +4lbs would increase consumption to 66 galls per hour, but should permit (according to the graph) 200 IAS within the acceptable revs range. The Air mpg drops to 6, and we'd need to increase that consumption for external tank drag, but it doesn't change things much. The relatively low consumption of the Merlin seems to stand it in good stead there, but I've always thought the P-47 cruised faster. I'd think 200 IAS cruise at escort height would be about the minimum we'd want over the continent. 200 IAS @ 25kft gets us 300 TAS, @ 30kft 327 TAS, ignoring P.E. and C.E. in both cases. snip even more general agreement Some IXs did get it, but I can't discover the logic or process involved at this stage. I increasingly wonder if it was a matter of "whatever the subcontractors deliver today." Any idea who made the internal tanks (if not Supermarine), and if there was more than one company involved? Yes, there were several firms involved, some locally around Southampton. I think CBAF made their own. I don't want to investigate that nightmare much further. snip Oh, admit it, you enjoy hunting through boxes of stuff at the PRO, peering at miniscule type on yellowed, 50+ year old mimeographed copies so you can discover that a/c in serial range XX-1XX through XX-127 were fitted with canopy enmergency release pin 2C-5392-9 rather 2C-5587-6, owing to the delivery van breaking down. No, but the service acceptances by the RAF seem to be (by a hand and eye count of the appendices in Shacklady & Morgan, so I can't claim any real authority for these figures) about 90 in July 1943, 98 in October, declining to 67 in November, 53 in December and 28 in January 1944. This doesn't reflect production figures per se, as the aircraft had often been in storage for some time or were shipped to Casablanca or India, and had actually been produced earlier. But it does give an indicator of deliveries, which is almost what you want. We're in fat city, then, and I see no need to mess around with Mk. Vs. This is where my political considerations kick in: the promises to the DAF, the 12th AF and the Russians and the Far East already exist and need to be serviced. Almost all the VIIIs being produced are being shipped out to overseas theatres. Which is why we'll replace them with Mk. IXs temporarily (Mk. VC Trops to the Far East if we don't have enough Mk. IXs), until we can ramp up production. If you want the whole of Mk VIII production, when does this decision get made? End of September '43 seems like a good date, and continuing for the next few months. My Mk V speculation was based on what would be likely with existing resources. 12 Group needed that range, and FC didn't give a stuff what they did with their Mk Vs (e.g. the LF Vb conversions at this time). Increasing internal tankage would be a small step to them, without major political considerations. I can only see this whole scenario working if FC actually have some resources capable of supporting a daylight effort; even the CAS can't complelely dictate operational tactics to an RAF C-in-C. We'll have to wait on AVM Stickney's Cg calcs, I think. Mk. VIII production rate Seems reasonable, although we'd want to boost Mk. VIII production well above 90/month, I'd agree, but frankly you're hitting the limit of the relevant production resource, i.e. the Hampshire production group focused on Supermarine's dispersed work. You might get 120 or so out of them per month of they packed up everything else, bar a couple of PR Spits and the beginnings of the Mk XIV. The next focus I suggest would be getting Westlands, finishing off their Mk V production run with Seafires to move to Mk VIIIs while tackling Castle Bromwich. I think you could fully convert to Mk VIII-based production by spring 1944, with an increasing number of rear-tank versions available within that output, and with the Mk XIV entering service at the same time. snip Sounds like the way to go. I'm not sure that we even need Castle Bromwich to transition. If we can get say 150-200 Mk. VIIIs a month, that will probably do the trick until we're on the continent and/or get our Mustangs. By all means, though, let's make sure we get at least 96 gallons in the Mk. IXs from now on. It's ridiculous to be building a/c with 85. Guy
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#15
August 21st 03, 10:46 PM
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Guy Alcala wrote:
snip Sorry for the multiple posts. My browser kept telling me that my ID was incorrect, and that the message hadn't been posted. Obviously, neither was correct. Guy
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#16
August 22nd 03, 05:40 AM
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#17
August 22nd 03, 01:28 PM
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On Thu, 21 Aug 2003 20:52:34 GMT, Air Commodore Guy Alcala, Director
of Fighter Operations wrote: At the rate you're going I'd better begin, before you retire and take over from Freeman at MAP. I shall miss your sagacity, judiciousness, dare I say genius, that has made my own job immeasurably easier. The country owes you a debt of gratitude that it can never repay. I remain, Sir, your most humble and obedient servant. I'm only holding this Production job down until I can replace Coningham in 2 TAF, which will let me play with all those new toys I'm producing for his command meanwhile. That's one of the reasons I want the XIV and I'm also breathing fire down people's necks to get the long-nacelled Meteor III available ASAP. P.S. Are the rumors correct that AM Hill is going to be promoted from AOC 12 Group to AOCinC ADGB, about mid-November? 12 Group will have to be the base for our long-range escort force, so we'll need an AOC there who's fully committed to making long-range escort a reality. Hill followed by Robb sounds good. You've already got some good Wing leanders, like Lloyd Chadburn at Digby and Laddie Lucas at Coltishall. Once the experiment is demonstrated to be successful, and the numbers of LR Spits expand , 11 Group bases like Martlesham, Bradwell Bay, Hornchurch and North Weald can be included. They'll be seeing more combat than the 11 Group Spit squadrons, so you can count on the more enthusiastic and aggresive squadron and wing commanders trying to get in on the act. My impression, and it isn't any more than that, but it is nonetheless based on some limited research on 125 Wing which fielded the first Spit XIV sqns in 2 TAF, is that 110 is representative of the RB-serials delivered in late '43 and early '44. Fine by me. The Mk. XIVs are for the continent anyway, as that 110 gives them about the same range as the Mk. IX, but less endurance. Initially my aim is to replace the Spit Vs in the 2 TAF squadrons with short-ranged XIVs and IXs for the invasion period. I also want to replace the LR Spit VIIIs and IXs in ADGB with Mustang III (LRs), with the deleted rear fuselage tank in 1944. Hopefully this can begin in the second half of 1944, and allow 2 TAF to re-equip with LR Spit VIII/IXs and LR XIVs to allow strategic escort operations to take place from 2 TAF bases in France and Belgium. By the second half of 1944, all Merlin-engined Spit production will be to an LR standard (enlarged 96 gallon front tanks, 27 gallon wing tanks and 75 gallon rear tank) so supply shouldn't be a problem. The leanest time will be in spring 1944, as LR wastage will only be replaceable from the Mk VIII production from the Eastleigh group as Castle Bromwich converts, and operational wastage will be high. There should be an easing during D-Day and Normandy, as the Germans move back to France to face the tactical fighters, and Castle Bromwich comes on stream. This should allow extensive re-equipment at the same time as Mustangs become available. There should be enough Mustangs to re-equip two wings (as in OTL; in this TL less Mustangs are being lost in spring 1944 as the LR Spits are taking some of the strain) which should go to 12 Group, and allow 11 Group to re-equip. Listen, I'm all for your LR VIIIs, and I'm even helping by pushing for rear-fuselage tanks for them, but the quid pro quo is XIV production beginning on schedule, and the fitting of rear tanks to them whenever possible. Whenever possible is fine, as long as it doesn't delay our increasing standard Mk. VIII production. The maximum loss to Mk VIII production will be 10 airframes per month in December 1943 - January 1944, any further increase being covered by new production of Mk VIIIs, or more likely from increasing LR IX production at Castle Bromwhich thereafter. I think you should be able to rely on a minimum allocation of 90 Spit VIIIs in October, November and December 1943, moving up to 100 to 120 per month for the first three months of 1944, and some of these appearing with rear-fuselage tanks. In return, I should be getting deliveries of 10 Mk XIVs per month from December to March 1944, going up to 20 and thirty per month thereafer as Griffon 65 production increases. Remember that the XIVs will be taking the short-ranged airframes first, and we won't start producing LR XIVs until you're getting about 200 LR series ii Spit VIII/IXs per month in April or May 1944. On the other hand, this will give us an excellent tactical fighter to counter the Fw190D, and one that can have rear-fuselage tankage installed at the end of 1944 to give us more intermediate-range escorts with Mustang-equivalent performance. I've just been thinking of this. Why not run the rear tank via a pump (or two for redundancy) to the main tanks to keep them full while running down the rear tank, just like the approach with the wing tanks? The one account I have of the L.e. tank usage says that they are transferred to the main(s) once space is available. Otherwise, the excess gets vented overboard, which is rather counterproductive. Yes, I think a direct feed from the rear tank and drop tank might be less of a handling problem, providing it was used after take-off and the initial climb, and the switch to the other tanks was done at the right time.. I'd think 200 IAS cruise at escort height would be about the minimum we'd want over the continent. 200 IAS @ 25kft gets us 300 TAS, @ 30kft 327 TAS, ignoring P.E. and C.E. in both cases. 2,400 rpm + 4lbs and 66 gallons per hour it is then. Yes, there were several firms involved, some locally around Southampton. I think CBAF made their own. I don't want to investigate that nightmare much further. snip Oh, admit it, you enjoy hunting through boxes of stuff at the PRO, peering at miniscule type on yellowed, 50+ year old mimeographed copies so you can discover that a/c in serial range XX-1XX through XX-127 were fitted with canopy enmergency release pin 2C-5392-9 rather 2C-5587-6, owing to the delivery van breaking down. Thankfully, this sort of detail generally isn't recorded at the PRO, although the odd bureucratic struggle between the MAP and Air Ministry and suppliers does emerge over troublesome embodiment loan equipment. This gives you some acerbic comments about Lucas electrics not delivering the generators required under contract x/xxxx-xx for Manchesters, but this not being a problem as Avro hadn't got the right mountings for the generators made yet anyway. The level of detail you want will be stored at the supplier and contractor's end, if it is recorded at all. Good luck! This is where my political considerations kick in: the promises to the DAF, the 12th AF and the Russians and the Far East already exist and need to be serviced. Almost all the VIIIs being produced are being shipped out to overseas theatres. Which is why we'll replace them with Mk. IXs temporarily (Mk. VC Trops to the Far East if we don't have enough Mk. IXs), until we can ramp up production. This is easier the earlier it is done: by September 1943 a lot of Mk VIIIs are on merchant ships, and you've only got a pool of a couple of dozen available to you in MU storage waiting to be shipped out. If you want the whole of Mk VIII production, when does this decision get made? End of September '43 seems like a good date, and continuing for the next few months. What provokes this at the strategic and political level? I'd suggest an earlier date, maybe June 1943 before Hamburg and before Schweinfurt collectively hyped BC and depressed the fortunes of daylight bombing. It would take a couple of months for the procurement decisions to be made and things shaken out to the point of doing something at the squadron end. [snip LR Vc on hold pending AMR&D AVM Stickney's report from RAE and A&AEE] Sounds like the way to go. I'm not sure that we even need Castle Bromwich to transition. If we can get say 150-200 Mk. VIIIs a month, That will need CBAF: it's beyond the capacity of Supermarine's at Eastleigh even with the marginals like Westland thrown in. that will probably do the trick until we're on the continent and/or get our Mustangs. By all means, though, let's make sure we get at least 96 gallons in the Mk. IXs from now on. It's ridiculous to be building a/c with 85. Yes, I think it should break down something like this. [Fantasy time, but this should have some rational basis after the thrashing we've given the subject] R&D 1. Development on Seafires at Eastleigh (Mk XV, etc) to stop immediately. FAA will survive Vc's being converted to Seafire IIIs and L.IIIIs from storage; i.e. no new output of Seafires once Westland have converted to the Spitfire Mk VIII. FAA to get by on US supply otherwise. 2. Development on F.21 at Eastleigh to cease and all R&D priority to switch to fitting LR tankage as detailed below to Mk VIII and IX airframe. Final production work on Mk XIV to continue, any further airframe allocation for R&D purposes to be cleared by AMR&D. Top priority on increasing Mk IX internal tanage to Mk VIII standard, then installing and clearing 75 gallon rear tank for operations in Mk VIII and IX no later than December 1943. Subsequently development work to be completed on installing same tank in MK XIV when supplies are available. Production 1. Eastleigh to continue maximum production of Mk Spitfire Mk VIIIs, to a minimum MAP quota of 100 per month, increasing to 120 per month by December 1943 as the highest priority. Entire output to go to ADGB. 2. All Spitfire production from all sources to standardise on enlarged Mk VIII tail on all production as soon as possible. 3. Eastleigh to begin production of maximum 10 Mk XIVs per month in December (plus quota of 10 in October for existing airframes), providing Mk VIII delivery minimum is fully completed. 4. Eastleigh to install 75 gallon rear-fuselage tanks in production (Mk VIII LR), beginning December 1943, with priority for equipping entire production output by March 1944. 5. Eastleigh to install 75 gallon RF tanks in production Mk XIVs (Mk XIV LR) when tankage becomes available (i.e. when assigned minimum of 200 LR Spit VIII/IXs are being produced with rear-tanks). Target date, July 1944. 6. Castle Bromwich to plan switch to Mk VIII airframe production, with report on required machine tools and assesment of impact on production output of Mk IXs. No action to be taken pending approval from AMP with consultation from DFO and AMR&D on acceptability of any production shortfall. [Marginal note scrawled by AMP: "No point accepting any shortfall of deliveries just for retractable tailwheels in all our Spitfire production when we're already getting the internal tankage which is the main point at issue."] 7. Castle Bromwich to maintain full production of Mk IXs, adding Mk VIII internal tankage (enlarged forward tanks and wing tanks) as a priority as soon as supplies of tanks become available after meeting Eastleigh's needs. Production to be spliced with Mk IX (LR series i) to be Mk VIII-equivalent. Supplies to be directed to ADGB as priority. 8. Castle Bromwich to install 75-gallon rear tank to begin June 1944 as Mk IX [LR series ii). Supplies to be directed to ADGB as priority. Taking a wild stab in the dark, I'll make some hopefully-not-totally-ridiculous minimum estimations of production. [figures for Mk VIII/IX [LR]/Mk XIV] Oct '43 - 90/10/10 Nov '43 - 100/10/10 Dec '43 - 120/10/10 Jan '44 - 110/20/10 Feb '44 - 110/30/10 Mar '44 - 110/50/10 Apr '44 - 100/80/20 May '44 - 100/100/20 Jun '44 - 100/100/20 Jul '44 - 90/120/20 Aug '44 - 90/120/30 Sep '44 - 90/120/30 Oct '44 - 80/150/30 Nov '44 - 80/150/30 Dec '44 - 80/150/30 I think there were about 300 Spitfires being produced per month in this period as a an approximate rule of thumb. These figures leave a remaining balance of shorter-ranged Spitfires for supply to other theatres and reverse-lend lease. All Spitfires built by October 1943 were Mk IX or better, as the Mk V production run ended at CBAF that month with the last half-dozen to be produced, so Merlin 60 supply shouldn't be an issue. By March 1944, I think it might be possible to have the entire production of Mk VIIIs with RF tanks, and the same for the LR IXs by the summer. The tank production is of course the biggest unknown and consequently the largest bit of fantasy, but the scaling up here shouldn't be too far from what Supermarine actually did with the Mk VII/VIII production earlier in 1943 and what CBAF did with the rear-tanked IXs and XVIs in late 1944. Gavin Bailey -- Another user rings. "I need more space" he says. "Well, why not move to Texas?", I ask. - The ******* Operator From Hell
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#18
August 24th 03, 01:05 PM
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On Sat, 23 Aug 2003 04:01:24 GMT, Guy Alcala
wrote: [tank plumbing] I'm not sure that accords with RAF standards. I finally got my hands on Price, and reading the specs for F.7/30, Part 2(B) "Fuel and Oil Systems," I'm not sure that would be allowable. OTOH, the spec may have changed. The re-armament sepcs were definately modified as a result of combat experience. The external slipper tanks which appeared in 1941 were unforseen in the original contracts, just like the need for bomb shackles and so on. I should just scan the Pilots Note's and send them to you. What provokes this at the strategic and political level? Nothing. As explained in my other post, this was originally a 'what if' thought experiment from ACM Kramer. Fair enough. But from my perspective it's more fun to ground this in a believeable context for a departure from the historical policy. [Spit range] at least 250-300 mile radius would seem doable when carrying a 90 gal. tank. What gives? The 85 gallon Mk. IX will be somewhat worse, but not all that much. The RAF were very conservative when planning fuel usage on operations. They gave a Spit LF IX a range of 365 miles on internal fuel, or 785 with a 90 gallon external tank. Yet the figures the planners for Cirucs ops used were 100 miles radius for big formations of Spit V/IXs and only 150 miles for "long-range" [external tank] profiles*. [* PRO AIR 14/407 "Co-ordinated Operations, Bombers & Fighters (Circus ops) Vol.2, 78B: Fighter Command Operational instruction 13/1943 - "Operational Endurance of Fighters", Appendix A. This gives the following breakdown: Type long sea-crossing/short-sea crossing/large formation Spit V/IX short-range 300m/240m/100m Spit V/IX long-range 420m/300m/150m] Using these figures, actual deployment in regard to operational ranges used on operations seems to be conservative: after D-Day, Spit V units based on 11 Group bases and ALGs were sweeping from Manston to Verdun on 90-gallon tanks, and Spit IX wings based on similar ALGs were escorting and sweeping to Paris and back. This was on a tankage profile that was identical to that available in 1942. The high-altitude Circus ops of 1941-42 did involve large and complicated wing assemblies over the southern coast of England at high altitude, which consumed time and fuel, and involved formating on slower bomber formations with zig-zag courses which all suppressed available range. Things did change in 1942-43, with low-altitude assemblies and mid-Channel climbs, as well as increasing external tankage. Nobody seems to have put two and two together and actually acknowledged the fact that they could actually escort a bomber force all the way to the German border and back with sequential waves of Spitfire escorts covering different sections of the route. In this respect, the USAAF benefitted from a strategic bombing policy which pulled the fighters out in support. British escorted bomber operations didn't dicate fighter operational deployment in the same manner. The conservative figures used for Group planners (i.e. understating the available fuel to avoid disaters like 133 Sqn's escort to Morlaix in September 1942) leave a big difference between the known individual range figures they used. BTW, those figures for the Mustang III from the same source (individual a/c stats) give it a range of 690 miles on internal fuel, or 1180 with a 90 gallon tank, while the planning figure for short sea-crossing, small number of a/c range (the best range figure) gives it just 600 miles. Speculatively using the same divisor for large formations on a big-sea crossing would indicate a contemplated range for operational planning purposes of only 200 miles. Gavin Bailey -- Another user rings. "I need more space" he says. "Well, why not move to Texas?", I ask. - The ******* Operator From Hell
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#20
August 27th 03, 06:20 AM
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