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I think it is usual that many Military study historical documents require extensive cross-referencing of detail facts. Of course, many such studies are very good but the accurate parts can be matched by inaccuracies. I think that Military studies made shortly after events can have good content from close involvement with the event but detail from "the other side" of the story can be thin. For example, I think that past Allied studies of Luftwaffe or German industry detail can fall short of the understanding available from some modern research.I do. That said it has a lot of factual errors.
I'm not sure that 'modern research' provides added understanding. Which works of recent times shed more light on circa 1945-1948 studies and reports, such as Strategic Bombing Survey or The Army Air Forces in World War II? My view on this subject is that it is hard to re-read and investigate plowed ground by starting from scratch and research the written words and records to build a story - one that didn't begin with pre-conceived opinions.I think it is usual that many Military study historical documents require extensive cross-referencing of detail facts. Of course, many such studies are very good but the accurate parts can be matched by inaccuracies. I think that Military studies made shortly after events can have good content from close involvement with the event but detail from "the other side" of the story can be thin. For example, I think that past Allied studies of Luftwaffe or German industry detail can fall short of the understanding available from some modern research.
I agree. Personally I have a habit of using several contemporary sources to cross reference specifics. That said, despite a few factual errors I have found in Boylon's Study 136, it is rich with specific citations/correspondence/orders that I personally tracked down and read - and used in my latest book.Another factor in Military history recording is that it was often written with bias and contemporary Military history recording can have huge holes in the recording events at the time. Modern Military studies are a tool of Staff training and so the author may not be particularly involved with the subject. Bear in mind that just because a study has a military source, it does not necessarily draw from accurate or privileged source material.
So, overall it is great to see these linked studies.
Eng
Roger Freeman thinks for P-47, external fuel radius, 84 gallons 280 miles, 108 gallons 325 miles, 165 gallons 375 miles, 215 gallons 480 miles, 300 gallons 550 miles, the final combination a pair of tanks. Going from 84 to 180 gallons gets you 3.75 mpg from the extra fuel, from 108 to 165 gallons 1.75 mpg, 165 to 215 gallons 4.2 mpg, 215 to 300 gallons 1.65 mpg. Fascinating if true about the drag different tanks had but more likely to reflect some are using the early 305 gallon internal fuel and others the later 370 gallons, the extra fuel adding around 215 miles to economic cruise range. The many times used range graphic has Spitfire 175 miles in May 1943, P-47 230 miles in June, 375 miles in August (Frankfurt, Kassel, Hannover just in range, Hamburg just out), P-38 520 miles in August and P-51 600 miles in early 1944. It would be very useful to find the 8th Air Force documents specifying how combat radius was calculated. Do not forget the extra pilot training and navigation aids required to enable an isolated fighter or small formation to find their way back from hundreds of miles out in less than perfect weather.
In days gone by people did that, to explain what happened and guide those who followed. Now in an age where no one admits to any mistake at all, any past error of judgement for any reason is used to destroy reputations, more so if it is admitted because that shows weakness and incompetence to people who have never ben in that position.Suppose it is natural to assume that each of the leaders post war bios may have selective recollections regarding unflattering circumstances, but recall that the Global Power and late Arnold Papers were sourced from his daily diary and he flat out accepts responsibility for failures and less than successful decisions. Ditto Eaker and Spaatz.
Thanks for all that interesting P-47 data. The other consumption figure is 20,000 feet, 3.03 mpg, 288 mph TAS, 95 g/hr. To me the figures say some of the loss in speed when carrying tanks is due to the engine not putting out as much power, as it is using around 10% less fuel. It also implies going from 288 to 302 mph, around a 2% increase in speed requires around a 20% increase in engine power, which is doubtful given the P-47D top speed.In terms of the performance penalty imposed by drop tanks, here are the Column IV cruise figures at 20,000 feet from the PFOI for the P-47 -25 to -35. Note that the Column IV figures were flight checked (the Column V numbers were preliminary).
2.67 air miles per gallon (302 mph TAS / 113 gph) — no external load
2.19 air miles per gallon (221 mph TAS / 101 gph) — 2 x 165 gallon drop tanks
ID | Src | Int | ext | radius | "mpg" | note |
1 | HunThou | 305 | 0 | 125 | 3.33 | |
5 | P-51B | 305 | 0 | 125 | 3.33 | |
10 | ExtCmbRad | 305 | 0 | 150 | 4.00 | |
16 | 8thTAC | 305 | 0 | 175 | 4.67 | 10,000 ft May 43 |
3 | HunThou | 370 | 0 | 225 | 3.21 | |
17 | 8thTAC | 305 | 0 | 230 | 6.13 | 10,000 ft Jun 43 |
6 | P-51B | 305 | 75 | 230 | 3.07 | |
27 | T&T | 370 | 0 | 230 | 3.29 | 2x1000lb |
11 | ExtCmbRad | 305 | 75 | 250 | 3.33 | |
14 | ExtCmbRad | 370 | 0 | 250 | 3.57 | |
25 | T&T | 370 | 0 | 260 | 3.71 | 2x500lb |
7 | P-51B | 305 | 108 | 275 | 3.01 | |
32 | Freeman | ? | 205 | 275 | n/a | Ferry tank? |
22 | T&T | 370 | 0 | 280 | 4.00 | |
28 | Freeman | ? | 84 | 280 | n/a | Official 75 gal tank |
12 | ExtCmbRad | 305 | 108 | 300 | 3.28 | |
29 | Freeman | ? | 108 | 325 | n/a | |
18 | 8thTAC | 305 | 75 | 340 | 4.53 | 10,000 ft |
26 | T&T | 370 | 108 | 360 | 2.90 | 2x500lb |
19 | 8thTAC | 305 | 108 | 375 | 4.10 | 10,000 ft |
8 | P-51B | 305 | 150 | 375 | 3.33 | |
30 | Freeman | ? | 165 | 375 | n/a | Official 150 gal tank |
23 | T&T | 370 | 108 | 400 | 3.23 | |
20 | 8thTAC | 305 | 150 | 425 | 3.78 | 10,000 ft |
2 | HunThou | 305 | 300 | 425 | 2.27 | 2x150 |
9 | P-51B | 305 | 300 | 425 | 2.27 | 2x150 |
21 | 8thTAC | 305 | 216 | 475 | 3.26 | 10,000 ft 2x108 |
33 | Freeman | ? | 215 | 480 | n/a | |
13 | ExtCmbRad | 305 | 300 | 500 | 2.67 | 2x150 |
31 | Freeman | ? | 330 | 550 | n/a | 2x165 |
24 | T&T | 370 | 300 | 575 | 2.61 | 2x150 |
4 | HunThou | 370 | 300 | 600 | 2.73 | 2x150 |
15 | ExtCmbRad | 370 | 300 | 700 | 3.18 | 2x150 |
Arthur Harris was only cleared for Ultra in February 1945, if at all, helping to explain his panacea oil targets ideas, any date for when Ira Eaker was cleared, again if at all? In 1943 the British were a lot more cautious over need to know. According to British intelligence in the Second World War : its influence on strategy and operations by F.H. Hinsley ; with E.E. Thomas, C.F.G. Ranson, R.C. Knight, January to June 1943 the RAF fighter command allowed 249 kill claims against Luftwaffe fighters, the true number was 235. While Luftwaffe fighter units in Germany would normally use land lines to report, those in France would normally use radio. Ultra and the Y service were keeping an accurate eye on Luftwaffe strength, dispositions and losses. The 8th Air Force should have known how accurate its bomber gunner claims were for operations over France at least, which were just under half of all targets attacked, along with Luftwaffe fighter dispositions including in Germany. The Air Force would also be well aware of its own sorties and losses.The opimism of Eaker was obviously misplaced due to a.) early 'success/low loss rates for escorted later unescorted shallow penetrations into W.GY; b.) Terrible claims processing of claims by bomber gunners - leading Eaker to believe 8th AF was inflicting unsustainable attrition by LW and could win the attrition war; c.) belief that the P-47C/D was adequate if only combat tanks could be installed for 'enough range' to punch through the perceived west wall of defense.
Gee, Butthurt ... is there a way to join your "fan club."?Greg apparently had his feelings hurt by me regarding 'contrarian' views on his P-47 series regarding range, and now his recent 'breathless' breaking news about Fokker being the real engineering and production cadre that built P-51.
I am banned
View: https://www.youtube.com/watch?v=TWr50TP0CWc&t=4169s
For those that can wade into 58 minute region I am referred to as 'butt hurt' author trying to prop up sales.
The posts that lurched me into the evildooer image was a point by point fact citation for reasons the P-47 was Not held back from true place of glory on the first Schweinfurt mission.
But the posts that apparently put me into the evildooer/must be banned penalty box was a point by point rebuttal of his conclusions that NAA could ONLY have built the Mustang with heritage Fokker team acquired by General Motors team, then named General Aviation Manufacturing Corp.
His conclusion; Edgar Schmued was Fokker Design, someone I don't know (and not on NAA org chart) was the production genius and Van Breese was responsible for NAA test group - all Fokker in his words - and were the catalysts for North American ascension as a builder of airplanes. He did note that a couple of executives came from Douglas in a passing swipe.
Those (unmentioned) execs were Kindelberger (former VP of Engineering at Douglas - and daddy of DC-1 and DC-2), Atwood (Asst Chief of Engineering at Douglas and Chief of Structures), Smithson (Chief of Production) along with Ray Rice.
Atwood became Chief, Engineering at NAA, Rice joined later as Asst Chief of Engineering and Smithson became VP Production. This is mid 1934 Mangement team first at GAMC, then NAA on Jan 1 1935.
Sadly Greg has no clue regarding actual operations at Fokker when GAMC was formed, nor understanding what was important when the F.10 crash killed Knute Rockne in early 1931.
Apparently he believes that Fokker was leading Fokker Atlantic engineering that designed the F.10 to compete with Ford Tri-motor - not so. Robert Noorduyn who came to US with Fokker in 1921, left Fokker in 1929. Apparently Greg believes that Edgard Schmued developed his talent as an engineer under the tutelage of Fokker Engineers. Not so, Schmued was hired just as Fokker resigned after Rockne crash. The new Chief's of engineering replacements were first Thaden from Pittsburgh Aircaft, renamed Metalaire in 1931 and acquired by GAMC in 1931.
The Department of Commerce - Aeronautical Division as a result of Rockne crash investigation issued edict concerning comercial passenger aircraft. No more wooded structural members for flight safety (F-10 deemed to have failed due to rotted wood wing spar).
At this moment in time there were several F.10 and F-8 Universal still on the line that were sold offshore. The Fokker XO-27 was flying with several orders for YO-27 nad one request for bomber version XB-7 - which Schmued worked on as first assignment. ALL Fokker designs and production airframes were of wood spar with plywood covered wings, steel tube and linen fuselages.
The Thaden T-2 and T-4 were welded tube metal covered fuselage with steel truss spar/linen covered wing now being built by Pittsburgh Aircraft when acquired by GAMC. The Pilgrim 150 was a low cantilever, steel tube, alclad covered wing plus steel tube structure, Alclad fuselage.
The second new boss was Virginius Clark (Clark Y airfoil) and former Chief, Engineering that designed the Fairchild-American Pilgrim 150. The boss and the Pilgrim 150 came in December 1931 - to replace Thaden. The 150 was assigned GA-43. It first flew May 1932. There wil be more on this later if you can stay awake.
By end of 1931, all metal single and twin engine aircraft are flying or on the Drawing Board. Included are B-9, Boeing Model 200, Douglas DC-1 and Boeing 247. GAMC ses the handwriting on the wall - which is why Fokker is not only effectively DOA for future design in commercial aircraft due to lack of inhouse expertise in either sheet metal fabrication or aerodynamics, or airframe structure analytic for these new technologies.
Compare Fokker F.10 to the soon to be introduced Douglas DC-1. The DC-1 could take off an fly on one engine. ALL Alclad stressed skin construction, twin engines, 10 passenger, flaps, and retractable landing gear.
But a little bit about NAA. It was a Holding company specializing in commercial air transport companies and airframe manufacturers. It acquired Eastern Airlines, Curtis Aircraft, SperyGyroscope. 40% Douglas Aircraft, then Berliner Joyce Aircraft, then GAMC. When NAA acquired GAMC, it consolidated three plants to one at Dundalk MD with approximately 150-200 employees remaining - then in turn was acquired by GM and divested of all commercial airlines save Eastern Airlines.
Summary, end of 1934.
All Teteboro Fokker/GAMC/Pittsburgh Aircraft aircraft had been completed, delivered, shut down.
American Pilgram 150/GAMC GA-43 completed at Dundalk as first actual NAA aircraft produced.
Berliner Joyce new development complete, only new orders for SOC-1 & -2 steel, welded floats are in production.
Senior management team execs Kindelberger (CEO), Atwood (Chief Engineering), Smithson (VP Production), Bowen (Production Engineer and future X73 project manager, then Asst Plant Manager at new Dallas Plant), Hansen (Chief Project Enginering) - ALL from Douglas Aircraft
Key Managers and future key employees Rice (Asst Chief, Engineering) - Douglas Aircraft, Schlecher (Chief, Airframe structures) and Baldwin (Project Engineer) and Rudd (tool & die maker who rose to VP&Gen Mgr NAA Columbus Div) came from Berliner Joyce. Schmued (Preliminary Design engineer at acquisition by NAA (GAMC)
Summary-
Every design produced by NAA from XO-47 (GA-15) and BT-9 (NA-16) through XB-21, BC-1, Export Fighter NA-44, AT-6, NA-40, B-25, P-51 were led by Atwood through 1939, Rice thereafter. Douglas origins.
Schmued became Chief, Preliminary Design in 1939 wth first effort the P-509/X73. The project team was matrixed but still in Rice's Engineering department.
The Production quality was driven by Kindelberger with focus on speed, quality and ever decreasing Cost. Smithson and imbedded project engineers worked closely with Design with an eye towards actual process, and process flow.
Schmued's genius were two fold. A superb intuitive feel for aerodynamic shape and ability to pick/lead and manage a preliminary design team to a schedule the preliminary designs.
Schmued also the driver for the development and implementation of Projective Geometry of applied conical sections. He pushed, Roy Liming constructed the application to the Lofting developments.
Additional Oddities
Nothing from Fokker related to manufacturing excellence, specifically not 'butt joint quality production that Greg cites as reason speed advantage over Spitfire. Curiously he didn't mention wing or Meredith effect as 'other reasons' for performance but all those lay at feet of Smithson, and Rudd including flush rivet passion and development of 7075 skin deelopment and techniques later. Nothing from Fokker instituted filling, sealing, priming and painting wing to achieve surface quality independent of butt joint construction.
Nothing from Fokker instructed Ed horkey, Ashkenas, Beerer (all Cal Tech grads) in the fine art of airfoil development, aerodynamics, performance analyss or Meredith effect cooling system design - the latter a far larger difference maker than butt joint construction.
Nothing from Fokker introduced alclad sheet stress panel analysis and design that was cornerstone of NAA quality and strength.
Greg cites Van Breese as one of the Fokker trained giants that vaulted the Mustang into glory?
Well, interesting that Van Breesehad his own aircraft company 1927-1934. Breese Aircraft Company. last operating at Mines Field. He co-designed the Vultee V-1. Was bought out during the Vultee consilidation. He DID consult with Fokker Netherlands as a Demonstrator test pilot for Various Fokker designs attempting to gain a foothold in 1937. From that approximate time he was basically a full time test pilot and consultant including a stint with NAA in 1939/40 for the NA-44 and then 73X
Now for the other side of the ledger.
The rapidity and excellence of the first big success of NAA Design - the NA-16 BT-9 - had a large contingent of Dutch speaking shop team that worked 18x7 to get the prototpe done in time to win against Seversky. While the GA-43 was largely GAMC (Pilgrim) workers, the BT-9 was welded steel tube fuselage and fabric covering for fuselage and wing - right in the strike zone for the surviving Fokker (and Berliner Joyce) cadre that made the trip to Dundalk.
If anyone feels like stirring up some stuff in Greg's new video, you have my permssion to cut and paste. Warning - you may get banned.
Sincerely,
Butthurt
but his sophomoric video is right up there with a certain unnamed US President who is "building back better."
All of the values are straight line course, drop tanks, engage, fly back with reserve. All, except as noted are for 10,000 feet. For changes in Mpg the primary causes were drag due to drop tanks. The 75s were cleaner than the 108/110 and the 108/110 was cleaner than the 150gal.Thanks for all that interesting P-47 data. The other consumption figure is 20,000 feet, 3.03 mpg, 288 mph TAS, 95 g/hr. To me the figures say some of the loss in speed when carrying tanks is due to the engine not putting out as much power, as it is using around 10% less fuel. It also implies going from 288 to 302 mph, around a 2% increase in speed requires around a 20% increase in engine power, which is doubtful given the P-47D top speed.
Putting all the range data into a table. ID is just a number to use for sorting, Src = Source, Int = internal fuel gallons, ext = external fuel gallons, radius = reported combat radius in miles, mpg miles per gallon = twice the radius divided by the total fuel less 91 warm up, take off and climb, 91 combat and 48 reserve gallons. Table sorted by radius, internal, external fuel.
Roger Freeman appears to be mostly quoting figures for 305 gallon internal fuel models, he also points out the differences between official and actual capacity, 75 official = 84 actual, 150 official = 165 actual, 200 official = 215 actual. The other references are using official capacity. The importance of altitude is clear. You can say the table is reasonably consistent, but to be sure requires cruise speeds, altitude, time taken to climb, assumed formation size and probably other factors. One obvious point, the underwing fuel tanks had a lot of drag, carrying fuel under the fuselage looks like the better option. Extension of Combat Radius says 75 gallons external = 65 gallons internal. How radius went from 175 to 230 miles without more fuel in Eighth Air Force Tactical Development figures needs explaining, having 66/51 extra gallons in wing tanks only gets you 100 more miles versus a 150/165 gallon belly tank, though Freeman thinks it is an extra 140 miles. References supplied by 33k,
ID Src Int ext radius "mpg" note 1HunThou 305 0 125 3.33 5P-51B 305 0 125 3.33 10ExtCmbRad 305 0 150 4.00 168thTAC 305 0 175 4.6710,000 ft May 43 3HunThou 370 0 225 3.21 178thTAC 305 0 230 6.1310,000 ft Jun 43 6P-51B 305 75 230 3.07 27T&T 370 0 230 3.292x1000lb 11ExtCmbRad 305 75 250 3.33 14ExtCmbRad 370 0 250 3.57 25T&T 370 0 260 3.712x500lb 7P-51B 305 108 275 3.01 32Freeman ? 205 275n/a Ferry tank? 22T&T 370 0 280 4.00 28Freeman ? 84 280n/a Official 75 gal tank 12ExtCmbRad 305 108 300 3.28 29Freeman ? 108 325n/a 188thTAC 305 75 340 4.5310,000 ft 26T&T 370 108 360 2.902x500lb 198thTAC 305 108 375 4.1010,000 ft 8P-51B 305 150 375 3.33 30Freeman ? 165 375n/a Official 150 gal tank 23T&T 370 108 400 3.23 208thTAC 305 150 425 3.7810,000 ft 2HunThou 305 300 425 2.272x150 9P-51B 305 300 425 2.272x150 218thTAC 305 216 475 3.2610,000 ft 2x108 33Freeman ? 215 480n/a 13ExtCmbRad 305 300 500 2.672x150 31Freeman ? 330 550n/a 2x165 24T&T 370 300 575 2.612x150 4HunThou 370 300 600 2.732x150 15ExtCmbRad 370 300 700 3.182x150
To my knowledge Eaker was never cleared for Ultra. RAF Intelligence however, warned Eaker that the bomber gunner claims were far overstated.AN 01-65BC-1APilot's Flight Operating Instructions for Army Models P-47D -25, -26, -27, -28, -30, and -35 Airplanes dated 25 Jan. 1945
America's Hundred Thousand Francis Dean
P-51B Mustang — North American Bastard Stepchild that Saved the Eighth Air Force James William "Bill" Marshall and Lowell F. Ford
Plate from a historical document entitled Extension of Combat Radius
Eighth Air Force Tactical Development — August 1942–May 1945
Tactics and Techniques Developed by the United States Tactical Air Commands in the ETO.
Mighty Eighth War Manual Roger Freeman page 221
Arthur Harris was only cleared for Ultra in February 1945, if at all, helping to explain his panacea oil targets ideas, any date for when Ira Eaker was cleared, again if at all? In 1943 the British were a lot more cautious over need to know. According to British intelligence in the Second World War : its influence on strategy and operations by F.H. Hinsley ; with E.E. Thomas, C.F.G. Ranson, R.C. Knight, January to June 1943 the RAF fighter command allowed 249 kill claims against Luftwaffe fighters, the true number was 235. While Luftwaffe fighter units in Germany would normally use land lines to report, those in France would normally use radio. Ultra and the Y service were keeping an accurate eye on Luftwaffe strength, dispositions and losses. The 8th Air Force should have known how accurate its bomber gunner claims were for operations over France at least, which were just under half of all targets attacked, along with Luftwaffe fighter dispositions including in Germany. The Air Force would also be well aware of its own sorties and losses.
That optimistic thinking departed ~ June 1943 when Eaker and Lovett beggd for P-38 and P-51. Arnold trumped the Air Defense Directorate in late July - which had allocation authority - and ordered that all Mustang and Lightning production for next three months be directed to ETO. Both the 20th and 55th FG P-38 equipped were first to arrive in August 1943 but the 55th deemed 'not ready' until after second Schweinfurt mission. The 20th began ops at end of December.Even west of the German border the loss rates were nearly unacceptable. Somehow the 8th Air Force was thinking it could still make partly or unescorted raids work.
In contract dated 1939/40 the USAAF ordered 512 B-17, 388 B-24, 863 B-25, 798 B-26, 60 P-35, 552 P-38, 703 P-39, 1,063 P-40, 134 P-43, 772 P-47, not quite the all out heavy bomber force.
The C/L, B-7 rack, 75 gal tank combination was about the same as the actual drag of two, uncluttered wing pylons.
An observation on no. 17 - there is no universe in which a P-47C/D achieved 6.13 with only a clean P-47. It uses far too much fuel from internal tanks at very low speeds before reaching cruise altitude. It was closer to 3mpg for a cruise radius of 125mi - That configuration is one of the very few configurations actually tested at Eglin in 1943.
No criticism on you or your effort, but if half the values reported by 8th TAC were anywhere close to reality, the second Schweinfurt mission would have been escorted to the target. They got as far as Aachen before turnng back. 75 gal combat tanks.
Nicely done vid.lol, in reviewing Masters of the Air Ep 7, the guys at Unauthorized History of the Pacific War clearly are referring to Greg or one of his acolytes at about 37 minutes into this video, regarding range of fighter escort in ETO.
Agreed - similar for XP-51F/G/J as well as D. All with P-51D bomb rack which is far cleaner than P-51B and P-38 and P-47 wing pylons. When I referred to the B-7 rack it was strictly pointed at the new Keel or early P47 as well as the bomb/fuel tank rack designed to release in flight.According to the PFOI for the P-51H, which has fully filled out cruise charts and a wide assortment of external load combinations, the drag from 2 x 75 gallon drop tanks was the same as for 2 x 500 lb bombs — the cruise chart figures for the two loads were identical.
The PFOI for all models of P-51B/C and early D refer to calculated values - ditto P-47B/C/D and the column V is for the 200gal tank which was not pressurized and would not feed above ~ 20,000 feet. IIRC the chart showed up to 15000 feet in Column V.It would help if there were a PFOI for the earlier P-47 models with a fully, or nearly so, filled out cruise charts. The two I have in digital form have incomplete data.
The PFOI for the RP-47B & C and P-47D & G (AN 01-65BC-1 dated 20 Nov. 1943) in Column IV has flight checked cruise figures for up to 30,000 feet; Column V (Maximum Air Range) has flight checked figures for up to only 10,000 feet.
The PFOI for the P-47D-25, -26, -27, -28, -30, and -35 (AN 01-65BC-1A dated 25 Jan. 1945) in Column IV has flight checked cruise figures for up to 20,000 feet; Column V (Maximum Air Range) has preliminary figures only and for up to 20,000 feet. It also has a cruise chart with 2 x 165 gallon drop tanks as the external load — Column IV figures are flight checked for up to 25,000 feet; Column V figures are flight checked up to 15,000 while the numbers for 20,000 and 25,000 feet are preliminary.
The radius figures from Eighth Air Force Tactical Development — August 1942–May 1945 are certainly at odds with the numbers from the other sources.
Thanks for that, a good way to compare their potential but they fly to their radius, get into a fight or not, if not they immediately turn back in case there is a fight on the way home, waving at the bombers as they turn. Loitering for say 20 minutes to provide target cover would cost a P-47 around 38 gallons or 50 miles from the radius.All of the values are straight line course, drop tanks, engage, fly back with reserve.
Would that be all at 20,000 feet except as noted for 10,000 feet?All, except as noted are for 10,000 feet.
Yes it is clear the wing racks and associated tanks hurt performance. Roger Freeman adds a pair of 150 gallon underwing tanks made handling difficult unlike the P-51. If you change the internal fuel on 17 from 305 to 370 gallons the mpg drops to 3.3 from 6.1The C/L, B-7 rack, 75 gal tank combination was about the same as the actual drag of two, uncluttered wing pylons.
An observation on no. 17 - there is no universe in which a P-47C/D achieved 6.13 with only a clean P-47.
I think part of the difference is the 8th TAC are at a very different altitude to the others. When it comes to the 200 gallon ferry tank usage the reports are half full, or 100 gallons, if it takes 91 gallons to get to altitude from take off then half full tanks were being dropped over Britain. Given how few operations were done using the tanks that probably reflects where those operations went. Setting a rule to stay below 20,000 feet and use the tank until starting to climb a given distance from the enemy coast would enable more fuel for a mission to Bremen or Hamburg for example than for one to Schweinfurt.if half the values reported by 8th TAC were anywhere close to reality, the second Schweinfurt mission would have been escorted to the target.
Interesting as his values largely align with the other references.Freeman's table values are not supported by any combat operation planning or results pre- 370gal internal tank, save straight line sweeps.
If Eaker was not cleared for Ultra a question is if someone in the HQ was, but probably not in 1943. Which leaves Eaker, like Harris, unsure exactly how good the source was when making decisions on what to believe.To my knowledge Eaker was never cleared for Ultra. RAF Intelligence however, warned Eaker that the bomber gunner claims were far overstated.
End June 1943 there were only 22 production P-51B, then again the Australians thought the Merlin Mustang was a good idea in 1942. The 8th was asking for external tanks from 1942 and were working on designs and British manufacture. The question becomes why did the Air Force, with the results to end June 1943 at least, carry out the July to October missions which were on average deeper into enemy airspace and against increasing resistance. The idea a 300 bomber force would reduce losses to acceptable level was not supported by the June operations or the operations against Germany in general, which raises the issue of where did the number come from and why it has made the histories.That optimistic thinking departed ~ June 1943 when Eaker and Lovett beggd for P-38 and P-51.
The 55th FG arrived on 26 August, first mission 15 October, the 20th FG arrived 16 September, first mission 28 December, similar time to first missions as the P-47 groups, 353rd 7 June to 12 August, 352nd 8 July to 9 September, 355th 8 July to 14 September, 356th 26 August to 15 October.Both the 20th and 55th FG P-38 equipped were first to arrive in August 1943 but the 55th deemed 'not ready' until after second Schweinfurt mission. The 20th began ops at end of December.
lol, in reviewing Masters of the Air Ep 7, the guys at Unauthorized History of the Pacific War clearly are referring to Greg or one of his acolytes at about 37 minutes into this video, regarding range of fighter escort in ETO.
That is the problem. Not all charts present the altitudes for values, but USAAF typically plotted 10,000 and 25,000. The 10,000 foot values in my experience always exceed the 25K ranges displayed for same loadout. Technically, there is less Lift Co-efficient at lower altitude reducing Induced drag enough to overcome advantage in lower parasite drag at higher altitudes - as well as less fuel expended to get to cruise altitude,Thanks for that, a good way to compare their potential but they fly to their radius, get into a fight or not, if not they immediately turn back in case there is a fight on the way home, waving at the bombers as they turn. Loitering for say 20 minutes to provide target cover would cost a P-47 around 38 gallons or 50 miles from the radius.
Would that be all at 20,000 feet except as noted for 10,000 feet?
good catch.Yes it is clear the wing racks and associated tanks hurt performance. Roger Freeman adds a pair of 150 gallon underwing tanks made handling difficult unlike the P-51. If you change the internal fuel on 17 from 305 to 370 gallons the mpg drops to 3.3 from 6.1
I think part of the difference is the 8th TAC are at a very different altitude to the others. When it comes to the 200 gallon ferry tank usage the reports are half full, or 100 gallons, if it takes 91 gallons to get to altitude from take off then half full tanks were being dropped over Britain. Given how few operations were done using the tanks that probably reflects where those operations went. Setting a rule to stay below 20,000 feet and use the tank until starting to climb a given distance from the enemy coast would enable more fuel for a mission to Bremen or Hamburg for example than for one to Schweinfurt.
IIRC the June 1943 ops did not have a 300 B-17 dispatched mission. The first was the Blitz Week July 28h split force strikes at Kassel (182) and Oschersleben (120) (Freeman:source) - of which only a total of 95 were effectives due to most of force (>150) returning due to weather. Only 37 of the Oschersleben force dropped bombs.. The total loss was high but could be rationalized by greatly reduced defensive firepower.Interesting as his values largely align with the other references.
If Eaker was not cleared for Ultra a question is if someone in the HQ was, but probably not in 1943. Which leaves Eaker, like Harris, unsure exactly how good the source was when making decisions on what to believe.
End June 1943 there were only 22 production P-51B, then again the Australians thought the Merlin Mustang was a good idea in 1942. The 8th was asking for external tanks from 1942 and were working on designs and British manufacture. The question becomes why did the Air Force, with the results to end June 1943 at least, carry out the July to October missions which were on average deeper into enemy airspace and against increasing resistance. The idea a 300 bomber force would reduce losses to acceptable level was not supported by the June operations or the operations against Germany in general, which raises the issue of where did the number come from and why it has made the histories.
Geoffrey I agree with much of what you write. That said, my records and Freeman agree 'circa' Aug 20th for 20th FG arrival, preceding 55th.The 55th FG arrived on 26 August, first mission 15 October, the 20th FG arrived 16 September, first mission 28 December, similar time to first missions as the P-47 groups, 353rd 7 June to 12 August, 352nd 8 July to 9 September, 355th 8 July to 14 September, 356th 26 August to 15 October.
As of mid 1943 the only other mid to then long range allied fighter was the Spitfire VIII with a 50 to 90 gallon external tank. As far as I know none were offered, none asked for. There would be command issues of the sort that meant the abandonment of the idea the USAAF would do defensive sorties in Britain, otherwise it seems about the priorities given to the various fronts, along with RAF ideas on long range for single seat fighters.
Edit: Air Marshall Richard Williams, RAAF representative in Washington, in a letter dated 20 July 1942 notes "The improved Mustang with Merlin 61 engine will not be in production until 1943." The first Merlin Mustang flew in Britain on 13 October 1942. It was part of a section discussing the need for fighters with performance at altitude to counter the Zero. Apparently the local USAAF had asked for P-47 and were being sent P-38 "reported everywhere as being heavy in maintenance."
That is the problem. Not all charts present the altitudes for values, but USAAF typically plotted 10,000 and 25,000. The 10,000 foot values in my experience always exceed the 25K ranges displayed for same loadout. Technically, there is less Lift Co-efficient at lower altitude reducing Induced drag enough to overcome advantage in lower parasite drag at higher altitudes - as well as less fuel expended to get to cruise altitude,
Can G Geoffrey Sinclair anddrgondog stick their heads together and make an article for a magazine about this subject?
You wont get rich...