P-51 fuselage fuel tank

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Notably, Lockheed and Curtiss and North American proceeded to develop and design wing and fuselage drop tank/sway brace capability in 1941/early 1942 on their own nickel. Spaatz was Chief Materiel Cmd for only a brief period, then Echols assumed command when Spaatz went to Air Plans - then in 1943 assumed command of 8th AF and brought Eaker as CO VIII Bomber Cmd.
 
To give an idea of how little importance the USAAF was attaching to long range they had actually STOPPED production of the 75 gallon drop tank.


The reality is that in the middle of 1943 the USAAF is not placing a high priority on escorts for the B-17 over Germany. They have transferred their longest range fighter from the UK to North Africa and they attitude towards drop tanks is lackadaisical to say the least. But the RAF is supposed to reduce production of the most important fighter in the ETO and MTO in order to compensate for the tardiness of of US. If the US isn't doing all it can why should the RAF.

Also note that the RAF was carrying all the load in defending the UK. One thing that Spitfire never gets credit for is the air tight cordon they placed over the UK. Between the Spitfire by day and the Mosquito by night the US never had to worry about their home base being bombed. When they did leave the protective cocoon of RAF Fighter Command they found out at great cost that the Russians did not have anywhere near that capability
 
Thats the difference between the Americans and British, the British found excuses as to why they couldn't do it, the Yanks just got on with it.
It took the Yanks over a year a half from the first B-17 mission over Europe to get it on with it and build a viable escort force . In January 1944 they were still futzing around with adding drop tank capabilities to P-47 and P-51s. The P-38s were finally being delivered with leading edge tanks and the P51s with fuselage tanks. Retro fits kits for both those aircraft were also arriving . Its not an accident that Big Week didn't start until February.


Appendices M through P contain quite a bit of information on drop tank tests
 

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It took the yanks over a year a half from the first B-17 mission over Europe to get it on with it and build a viable escort force
But they did it that's the difference, the British new their fighters lacked range and that indirectly lead to the blooding of the RAF in 1941 over France. I don't buy we didn't have time, didn't have resources etc, they had time and resources to fit the Merlin 45, 20mm Hispano's, design belt feed, change over to constant speed props, fit pilot armor, metal covered control surfaces and finally the Merlin 60 series with all new cooling system and wings, fitting the 29G rear tank took no time in the MkV, stupid thing is after fitting them for ferry flights they removed them, Stupidity at it's worst.
 
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By having an extra 20G the fighters could have been launched earlier allowing for optimal positioning for attack. During the BoB fighters were held on the ground until the last minute, they had to wait until the plotters were satisfied what the target was before releasing the fighters for launch, this caused them to be constantly attacking from underneath or from less than ideal positions, that extra 20G would have had them at 20,000ft before attacking or likewise fuel to reposition.
 
The extra weight of the tank and fuel etc are going to weight as much as a second crew man which will have significant impact on the rate of climb.
 
The extra weight of the tank and fuel etc are going to weight as much as a second crew man which will have significant impact on the rate of climb.
I was waiting for this exact reply. With an extra 10 minutes of fuel the need for max climb rate is null and void, as soon as the incoming raid's direction is plotted the fighters are launched and will be race tracking at 20,000ft before the bombers cross the coast, the need for a high climb rate is because they don't have enough fuel to do anything other than point defense. The P51 got rear Berlin tanks from late December '43? when the missions they flew required more internal fuel, and numerous different sized drop tanks.
 

Thank you for this, Jim. I have always wondered if there were any handling issues due to the aft CG with all the TF-51D restorations we see these days. Doing the math gave me about half the weight of a full tank in WW2, so I assumed things are fine, but it's nice to have your post talking about the issue.
 
A P-38 with external drop tanks forced to maneuver was definitely an issue. McGuire discovered that issue too late.

McGuire knew that long before that day... it was in the squadron SOP (as it was in ALL P-38 squadrons' SOP manuals), and he was well-known for emphasizing to pilots his combat rules... one of which was to NEVER enter combat without first dropping the external tanks, another of which was to NEVER get into a turning fight at low altitude, and the third of which was to never enter a fight below 300 mph.

The fight that killed him was a mission where they were cruising at low altitude, and a single Japanese fighter "bounced" them from above - they began defensive maneuvers without gaining much speed. When the enemy fighter got on the tail of a US pilot McGuire tried to help - still with his tanks under his wing, at about 200', and well below 300mph, he then tried to turn into the enemy and stalled out.

He broke all three of the combat rules he himself actively taught - his fellow pilots were completely confused as to why he did that.
 
I suspect that self preservation was lower in his mind than saving his wingman. IIRC they needed all the fuel remaining in the tanks to get home safely, but frankly don't know where that information came from.
 
No, they did not.
Yes they did, quote

The Mk XVI was the same as the Mk IX in nearly all respects except for the engine, a Merlin 266. The Merlin 266 was the Merlin 66 and was built under licence in the USA by the Packard Motor Company. The "2" was added as a prefix in order to avoid confusion with the engines, as they required different tooling. All Mk XVI aircraft produced were of the Low-Altitude Fighter (LF) variety. This was not determined by the length of the wings (clipped wings were fitted to most LF Spitfires), but by the engine, which had been optimized for low-altitude operation. All production Mk XVIs had clipped wings for low altitude work and were fitted with the rear fuselage fuel tanks with a combined capacity of 75 gal. Many XVIs featured cut-down rear fuselages with bubble canopies. On these aircraft the rear fuselage tank capacity was limited to 66 gal. A total of 1,054 Mk XVIs were built by Castle Bromwich
 
I misunderstood. You are actually proposing to scrap the so called Downing System and replace it with standing patrols. The irony of that is the Downing System was designed to elimate standing patrols. The argument against standing patrols is that they are wasteful of resources. More run time on engines and airframes means more frequent maintenance which obviously means more maintenance personnel and more parts. Pilots also become fatigued more quickly requiring more pilots. Fuel consumption rises of course. You are proposing a more than 30% increase in fuel load which roughly would equate to a 30 % increase in flying time, a substantial burden on resources.
Further more your thesis requires making decisions based on incomplete information which will mean there will be a greater chance of waiting resources on an inappropriate response.

I am also curious to see some actual examples of where fighter command delayed launching based on the Spitfire's endurance.
 
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Are you saying an extra 20 gallons plus tank did not affect take off runs, rate of climb and turn and stability of a 1939 Spitfire Mk I with fixed pitch prop and 85 octane fuel? Was running out of fuel an issue or more of an issue than not getting in the air and at altitude quick enough? Re writing how a battle should have been fought is easy after the event. If you could have sent Dowding and Park back from 1941 to 1935 they would have changed many things. By that time in 1941 they knew the war started in 1939 and France fell in 1940. If the 20 gal ferry tank was removed I presume there was a reason, like it did affect performance or was not self sealing. I dont know why the Spitfire gets it in the neck over range all the time, Allisson engined planes dont for their lack of altitude performance without a turbo. Until 1943 only the P-38 had range and high altitude performance, the P-47 didnt appear in service until April 1943. The Sabre and Typhoon had problems so they never replaced the Spitfire. The Vulture and Tornado also were abandoned. The failure of everything else meant that the best engines were given to the Hurricane to keep it marginally competitive. The Mk III wasnt produced because the RAF preferred more Mk Vs which used the Mk I/II fuselages already made. The MK VII and VIII were produced in smaller numbers because the RAF preferred more of the Mk IX which also used Mk V fuselages already made. The Mk V and Mk IX were made to produce more Spitfires rather than wait and produce better Spitfires. The decision mainly forced by the failure of everything else, the Spitfire itself should have been replaced.
 
Hi
We should remember that the 'Dowding' system had to be flexible as it had to react to the enemy's changing tactics. Dowding's Despatch mentions the following in para 215:
"One very tiresome feature was that a considerable proportion of ultra-high-flying raids was missed by the Intelligence system, or reported so late that time was not available to climb and intercept. This made it necessary to employ standing patrols just below oxygen height (about 16.000 feet). These patrols climbed to intercept at extreme height when ordered to do so. This cut into the roots of the Fighter Command system, which was designed to ensure economy of effort by keeping aircraft on the ground except when required to make an interception."

So obviously they had the fuel to undertake those missions, indeed they were more worried about the oxygen supply lasting (these were standard aircraft) which is why they patrolled below oxygen height.

Mike
 
On The Radar Pages I read that high altitude raids were outside the Chain Home calibrated beam. To detect them at all required side lobes of the main beam which meant some luck was involved, if a raid was detected, in a side lobe returned signal strength isnt proportional to distance or raid size which meant the plotters made understandable errors. In principle it is the same in Ultrasonics which used to be part of my job.
 
Note that when the 8th adopted the British paper tanks they sent some to Wright Field for evaluation. Many months later Wright Field reported they were unsuitable. The 8th had already found the tanks were useful and ignored them.
Meanwhile, Lockheed was working on the problem and designed tanks that were useful not only on the P-38 but also the P-47, P-61, PV-1, P-82 and P-80.
 
You are actually proposing to scrap the so called Downing System and replace it with standing patrols. The irony of that is the Downing System was designed to elimate standing patrols.
I'm proposing neither, what I am saying is the extra fuel allows the Spitfires to take off earlier so gaining both an altitude and tactical advantage over the incoming raid, chain home made standing patrols obsolete.
 
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Are you saying an extra 20 gallons plus tank did not affect take off runs, rate of climb and turn and stability of a 1939 Spitfire Mk I with fixed pitch prop and 85 octane fuel?
I'm pretty sure the BoB was fought in 1940 and no Spitfire or Hurricane that took part had fixed pitch props or was running on 85 octane fuel.
 

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