Did the RAF have designs for a long range escort fighter?

[stubbsy]

Then I think you'll like how 'A Blind Spot?..' deconstructs Leigh-Mallory's thinking on the long-range fighter issue and the American decision to ignore his direction and side-line him at every opportunity after they called him out on the topic.

I am confused how you come to the conclusion that 'increasing the Spitfire's range was nothing, whatsoever, to do with the RAF, because it had everything to do with the RAF's decision that there was no requirement for a long-range fighter (ref AIR 20/3605, Air Fighting Committee Minutes, 9 Jun 1937 Item II paragraph 50). The Air Fighting Committee was chaired by the DCAS, Sholto Douglas. 'A Blind Spot?..' also explains why the American configuration for internal fuel, together with long-range external tanks for the Spitfire, conducted at Wright Field, were specifically the result of the USAAF's annoyance with Portal and Leigh-Mallory in doing very little to increase the range of the Spitfire.

The use of the phrase 'lean towards Europe' in 1941 may have been influenced by Leigh-Mallory's memo of 5 Sep 1941 to SASO Fighter Command, in which he said 'I believe that the diversion of even 5% of our heavy bombers to regular "Circus" operations would enable such a high toll of enemy fighter pilots as to embarrass his Eastern Operations' but was actually coined by Trenchard/Portal as described by Sholto Douglas (AOC-in-C Fighter Command at the time) ref. Sholto Douglas, Years of Command (London: Collins, 1966), 113–14]

Essentially, Trenchard was right on this topic, but only when the Americans used their numerous P-47's with long-range tanks, supplemented with their less numerous P-51's, did the tactic work. The problem with leaning towards Europe was not the concept of offensive activity but the methodology and numbers to achieve the desired effect, something beyond the mental capacity of Sholto Douglas and Leigh-Mallory.

 

[tomo pauk]

It is interesting to note that a 'single stage' Spitfire with extra, say, 50% more fuel, gets plenty of verbal Flak. Yet it is considered acceptable that Hurricane was conceived around a huge thick ~260 sq ft wing, that is going to harm the performance much more than some extra fuel. It was considered acceptable to use it vs. Bf-109 even after BoB proved it lacks performance. Once it received the Merlin XX, the armament weight was upped, and killed most of possible performance gain??
Nobody in RAF was removing fuel tanks from their P-40s, despite their 'low performing' engines.
It was acceptable to have people flying the Blenheims in 1941-43, or the Spitfire Vs in 1944.

Further, the LR fighters are not supposed to fly alone, but to provide escort, and then defender has a tough choice of either go for the bombers, or to deal with escorts - either choice has it's disadvantages.
The short range interceptor fighter also has to have better heavier armament than the LR fighter, so whatever weight penalty is in extra fuel, such is also in having a heavier battery. In the P-38, the 20 mm cannon installation and 150 rounds weighted 288 lbs, about same as the full, self sealing tank with 40 US gals? Internal fuel tanks also have no drag penalty, unlike the cannons.

 

[Shortround6]

You also had had to have the planes capable of carrying out the strategy/tactic in hand. Not 6 months or two years down the road.

For what was considered possible by the USAAF and ultimately Lockheed in 1937 please see the P-38 and P-39.

P-38 "the Model 22 won Design Competition X-608 and on June 23, 1937, Lockheed was awarded a contract for one XP-38 prototype (Ser No 37-457). " from Joe Baughers web site.
The initial requirements for the P-38 and P-39 called for identical armament, identical top speed at identical altitude. The difference was that the the X-608 competition called for twice the endurance of the X-609 competition which lead to the P-39. Hibbard and Johnson figured they needed a 1500hp engine to meet the requirement with double the endurance of a plane with a single 1000hp engine. With no single 1500hp engine available they went for the twin engines.
Now please remember that the Merlin went from 880hp for take-off in 1937/38 to about 1200hp in 1941 and about 1280hp in 1942 and early Merlin Mustangs were rated at 1380hp for take-off and later ones for 1490hp. Merlin III was good for 1030hp at 16,250ft and some of the single stage Merlins were good for several hundred more HP for very little increase in weight and the two stage Merlins could offer hundreds more HP thousands of feet higher for the weight of the supercharger/ bigger prop and bigger radiators and intercooler. A "long range" fighter with single Merlin just wasn't possible in 1937/38 using existing supercharge technology and fuel ( or rather such an aircraft would have been at a severe disadvantage vs a short range fighter using an equivalent engine.

The British "brass" may very well have not been able to wrap their heads around the rapidly changing technology and possibilities but just because they wrong in 1942/43 does not mean they were wrong in 1937/38.

 

[Balljoint]

There's a good bit of truth to the long-range vs short range fighter capability. However, when the interceptor is tasked with avoiding the escort and reaching the bombers, the balance changes. With dissimilar resources, both people and material, the balance further changes. This wasn't apparent in early 1941. The ugly duckling P-51A was not left to fade away only by its improbable conversion to the A-36.

If foresight is lacking, it helps to be agile –and lucky- on the rebound.

 

[tomo pauk]

You also had had to have the planes capable of carrying out the strategy/tactic in hand. Not 6 months or two years down the road.

For what was considered possible by the USAAF and ultimately Lockheed in 1937 please see the P-38 and P-39.

P-38 "the Model 22 won Design Competition X-608 and on June 23, 1937, Lockheed was awarded a contract for one XP-38 prototype (Ser No 37-457). " from Joe Baughers web site.
The initial requirements for the P-38 and P-39 called for identical armament, identical top speed at identical altitude. The difference was that the the X-608 competition called for twice the endurance of the X-609 competition which lead to the P-39. Hibbard and Johnson figured they needed a 1500hp engine to meet the requirement with double the endurance of a plane with a single 1000hp engine. With no single 1500hp engine available they went for the twin engines.

Thanks for the overview.
USAAF wanted interceptors. Hence the strive for 37mm cannons in the future P-38 and P-39, along with multiple MGs. The 37mm cannon alone was 240 lbs, plus ammo meaning 300 lbs - equal to 40 US gals in s-s tank? We can also recall that XP-39 was to carry 200 US gals, and P-40 180 US gals of fuel.

Now please remember that the Merlin went from 880hp for take-off in 1937/38 to about 1200hp in 1941 and about 1280hp in 1942 and early Merlin Mustangs were rated at 1380hp for take-off and later ones for 1490hp. Merlin III was good for 1030hp at 16,250ft and some of the single stage Merlins were good for several hundred more HP for very little increase in weight and the two stage Merlins could offer hundreds more HP thousands of feet higher for the weight of the supercharger/ bigger prop and bigger radiators and intercooler. A "long range" fighter with single Merlin just wasn't possible in 1937/38 using existing supercharge technology and fuel ( or rather such an aircraft would have been at a severe disadvantage vs a short range fighter using an equivalent engine.

The Defiant I was an rater overweight fighter, yet it have had no problems taking off with 880 HP from RAF's standard airstrips.
As for what fighter is in disadvantage, the surprise, current height speed advantage beat couple of tens of fps every day of the week. Especially if the short range fighter need to kill bombers 1st, and caries a heavier draggier weapons battery than the LR fighter.
If something was impossible in 1937-38, does not mean it was not possible in 1939-41.

The British "brass" may very well have not been able to wrap their heads around the rapidly changing technology and possibilities but just because they wrong in 1942/43 does not mean they were wrong in 1937/38.

The Whirlwind was a result of a specification issued in 1935, Gloster F.9/37 from 1937 (?); neither specification included a fuel tankage suitable for long range work. The brass was not interested in it, even when there was enough of horsepower installed.
Brass also have had no objection in a turret fighter, where both weight and drag penalties from the turret installed were much higher than when an extra fuel tank is installed. Despite only half of firepower the Hurricane had.
The time spans quoted leave out the crucial time span of 1939-41 again.

 

[stubbsy]

Except, of course, the 'Brass' were wrong in 1937/38, as at the time they believed that in the next war bombers would not suffer unacceptable losses if not escorted. The experience of the RAF's 9 and 37 sqns over the Heligoland Bight on 18 Dec 1939, exposed the fallacy of the is thinking - though many senior RAF officers analysing the disaster immediately afterwards were so fixed in their thinking that they persuaded themselves that poor leadership - rather than the lack of escorting fighters - was what caused the unacceptable losses. Only when losses continued on similarly unescorted missions did the penny drop.

 

[Edgar Brooks]

I am confused how you come to the conclusion that 'increasing the Spitfire's range was nothing, whatsoever, to do with the RAF, because it had everything to do with the RAF's decision that there was no requirement for a long-range fighter.

I was talking about the physical (i.e. engineering) aspect of getting extra fuel into the airframe, not the necessity of it in the strategy of air fighting. The RAF could ask, but only the Air Ministry/government could give the go-ahead for the work to be incorporated in the factories.

 

[Shortround6]

It is interesting to note that a 'single stage' Spitfire with extra, say, 50% more fuel, gets plenty of verbal Flak. Yet it is considered acceptable that Hurricane was conceived around a huge thick ~260 sq ft wing, that is going to harm the performance much more than some extra fuel. It was considered acceptable to use it vs. Bf-109 even after BoB proved it lacks performance. Once it received the Merlin XX, the armament weight was upped, and killed most of possible performance gain??
Nobody in RAF was removing fuel tanks from their P-40s, despite their 'low performing' engines.
It was acceptable to have people flying the Blenheims in 1941-43, or the Spitfire Vs in 1944.

Further, the LR fighters are not supposed to fly alone, but to provide escort, and then defender has a tough choice of either go for the bombers, or to deal with escorts - either choice has it's disadvantages.
The short range interceptor fighter also has to have better heavier armament than the LR fighter, so whatever weight penalty is in extra fuel, such is also in having a heavier battery. In the P-38, the 20 mm cannon installation and 150 rounds weighted 288 lbs, about same as the full, self sealing tank with 40 US gals? Internal fuel tanks also have no drag penalty, unlike the cannons.

You have to go back to the proposals. The P-38 was not intended to use the 20mm gun. It was intended to have about 1000lbs of armament ( service planes carried 60% more easily). Originally it was supposed to use a 25mm gun ( which never got beyond prototype stage) then the 37mm gun and finally the 20mm gun, Machine gun armament and ammo tended to bounce around quite a bit also but then so did the engines which "grew" from nominal 1000 hp engine to 1090 hp at 13,200 feet in the XP-38 to 1150 hp engines in the YP-38 to 1325hp engines in the P-38F which start to roll out the factory door in March of 1942. That takes you form proposal to first truly combat capable model. Over a 30% increase in power although a there was also a substantial increase in weight.

The British faced a few minor problems. (sarcasm).

"Yet it is considered acceptable that Hurricane was conceived around a huge thick ~260 sq ft wing, that is going to harm the performance much more than some extra fuel"

The Hurricane was "conceived" around that big thick wing in order to get the field performance (take-off and landing distances and speeds) the RAF wanted at the time. Hawker had no wind tunnel of their own and believed what the RAE boffins told them, that the thick wing was NOT a drag problem. In 1940/41 you had multiple factories tooled up and spitting out Hurricanes in large quantities. It is not until the summer of 1941 that the Procurement people can say (Wew, The Germans just invaded Russia so we can stop/slow down production of what ever aircraft we are tooled up for and think about something else (better models). Perhaps the British should have tried harder to convert one or more Hurricane assembly plants to Spitfires but 1940 is 5-6 years after the Hurricane was conceived.

Blenheim carried on for far too long because the expected replacements were failures. Doesn't mean the British should have hobbled more of their aircraft to try to push for a certain tactic.


Speed of the Hurricane II was rather lacking but climb performance received a rather nice boost at certain altitudes (at 28,000ft the climb rate was roughly doubled from 570fpm at 6750lbs to 900-1100fpm at 7400lbs, charts vary )

BTW changing the Hurricane I from 6316lbs to 6750lb added over 2 minutes to the time take to go from 20,000ft to 30,000ft. granted the engine was limited to 2600rpm for the test but it is an indication of what 6-7% increase in weight could do (only knocked off 6mph or less from top speed). 20% decrease in rate of climb but only a 2% decrease in speed?? And again, rate of climb is an indicator of a planes ability to do a sustained turn without losing altitude. Doesn't matter that much if you can pull a 6 G turn at a radius smaller than your enemy if you have to lose hundreds of feet of altitude more per 360 turn.

Hurricane's take-off distance went from 370 yds at 6040lbs with fixed pitch prop to 280 yds at 6363lbs with 2 pitch to 240 yds with Rotol prop at 6316lbs to 280 yds with Rotol at 6750lbs. Rotol Props only came in at the end of 1939/ beginning of 1940 and They were converting the DH 2 pitch props to constant speed in the Summer of 1940, between the Battle of France and the BoB.
Added weight came from armor, bullet proof windscreens, self sealing tanks and more radio gear (like IFF) some of which also added drag.



In 1939/40/41 very few people were building "bomber" interceptors" (the US was actually almost alone in that), instead the single seat/single engine fighters were mostly all purpose.

As far as an "escort" being able perform it's mission if it's performance was not close to the interceptors see the Bf 110. It was faster (enough to win a bar bet?) and more heavily armed than the Hurricane, it could not climb or turn as well.

It is not enough to 'escort' the bombers, the escort mission must also be done at a low enough loss rate to allow continued operations otherwise it is just a matter of weeks or months before there aren't enough escorts left.

 

[stona]

Except, of course, the 'Brass' were wrong in 1937/38, as at the time they believed that in the next war bombers would not suffer unacceptable losses if not escorted. The experience of the RAF's 9 and 37 sqns over the Heligoland Bight on 18 Dec 1939, exposed the fallacy of the is thinking - though many senior RAF officers analysing the disaster immediately afterwards were so fixed in their thinking that they persuaded themselves that poor leadership - rather than the lack of escorting fighters - was what caused the unacceptable losses. Only when losses continued on similarly unescorted missions did the penny drop.

The penny didn't drop for the USAAF in 1939/40, even with the evidence from the British experience to hand.

For the Luftwaffe in 1940 even escorted bombers proved to be too vulnerable in daylight when confronted with a well coordinated and determined defence from the sort of short range interceptors that had been developed in the pre-war years. There is only so much pie to go around, in the 1930s just as now.

Hindsight is a wonderful thing, but those at the Air Ministry in the mid 1930s didn't have the benefit of it. Neither were they alone in lacking foresight.

Cheers

Steve

 

[Edgar Brooks]

Yet it is considered acceptable that Hurricane was conceived around a huge thick ~260 sq ft wing, that is going to harm the performance much more than some extra fuel. It was considered acceptable to use it vs. Bf-109 even after BoB proved it lacks performance. Once it received the Merlin XX, the armament weight was upped, and killed most of possible performance gain??.

Actually, the RAF told Tizard 29-4-41 that they considered that the Hurricane was already at the end of any possible development, and that the Typhoon and tornado should take over as soon as possible. There seems to be this general memory loss, that the Hurricane and Defiant were designed around an expectation that they would only have to deal with bombers and the Me110; demanding instant reaction to the unexpected loss of France in 1940, and an immediate appearance of a fighter capable of taking on the Me109 over the occupied territories is somewhat unrealistic.

It was acceptable to have people flying the Blenheims in 1941-43, or the Spitfire Vs in 1944.

It was unavoidable, not acceptable; the Spitfire V was considered obsolete in 1942, but there was simply not the factory capacity (not just airframes, but engines as well) to turn out the more capable fighters; the Spitfire XII was built only because of a shortage of low-altitude Merlins, so the Griffon had to come into service before it was really ready.
Eisenhower wanted the Spitfire IX for Torch, but couldn't have them because there still wasn't (yet) a viable tropical air intake/filter.

 

[Shortround6]

There is also the fact that in Poland in 1939 the Germans were still using some Bf 109Ds with Jumo engines. The Hurricane I, even in April, May, June of 1940 was better than most French fighters and better than any Italian fighters IN SERVICE at the time. May of 1940 also sees the first 11 P-40s built/delivered.

A Hurricane II could expect to take on a Bf 109E-3/4 with a pretty fair chance, it was the F that put the Hurricane into the obsolete category. And even that took a little while.

 

[tomo pauk]

You have to go back to the proposals. The P-38 was not intended to use the 20mm gun. It was intended to have about 1000lbs of armament ( service planes carried 60% more easily). Originally it was supposed to use a 25mm gun ( which never got beyond prototype stage) then the 37mm gun and finally the 20mm gun,

Thanks for the correction.

Machine gun armament and ammo tended to bounce around quite a bit also but then so did the engines which "grew" from nominal 1000 hp engine to 1090 hp at 13,200 feet in the XP-38 to 1150 hp engines in the YP-38 to 1325hp engines in the P-38F which start to roll out the factory door in March of 1942. That takes you form proposal to first truly combat capable model. Over a 30% increase in power although a there was also a substantial increase in weight.

Let's not forget the P-38D and -E, with 2x1150 HP engines and 1000-1500 lbs of armament ammo.

BTW changing the Hurricane I from 6316lbs to 6750lb added over 2 minutes to the time take to go from 20,000ft to 30,000ft. granted the engine was limited to 2600rpm for the test but it is an indication of what 6-7% increase in weight could do (only knocked off 6mph or less from top speed). 20% decrease in rate of climb but only a 2% decrease in speed?? And again, rate of climb is an indicator of a planes ability to do a sustained turn without losing altitude. Doesn't matter that much if you can pull a 6 G turn at a radius smaller than your enemy if you have to lose hundreds of feet of altitude more per 360 turn.

Hawker installed 4 cannons in the Hurricane IIC, that also meant a considerable drop in RoC vs. the IIA/B, yet the extra fuel and more modest armament set-up seem to be a no-no. Granted, expecting the Hurricane to perform a long range work vs. any decent air defense is looking for problems.

Hurricane's take-off distance went from 370 yds at 6040lbs with fixed pitch prop to 280 yds at 6363lbs with 2 pitch to 240 yds with Rotol prop at 6316lbs to 280 yds with Rotol at 6750lbs. Rotol Props only came in at the end of 1939/ beginning of 1940 and They were converting the DH 2 pitch props to constant speed in the Summer of 1940, between the Battle of France and the BoB.
Added weight came from armor, bullet proof windscreens, self sealing tanks and more radio gear (like IFF) some of which also added drag.

Unfortunately, Hawker didn't said: we can offer a fighter that uses less than 400 yds to take off and can do 320 mph, and we can also offer a fighter that needs 500 yds and can do 350 mph; what would you (RAF/AM) buy?

In 1939/40/41 very few people were building "bomber" interceptors" (the US was actually almost alone in that), instead the single seat/single engine fighters were mostly all purpose.

Westland was building 4 cannon fighter. Four cannon versions of the Hurricane and Spitfire were also under development, with performance penalty vs. all-Browning and mixed armament versions.
RAF's fighters 1st role being to kill LW bombers, until France fell?

As far as an "escort" being able perform it's mission if it's performance was not close to the interceptors see the Bf 110. It was faster (enough to win a bar bet?) and more heavily armed than the Hurricane, it could not climb or turn as well.

Not the Bf-110, however it's technicalities were just a part of it's problem during the BoB. I'd pick the P-40B, Re.2001 and Ki-61 - all aircraft with modest engine power, plenty of fuel and, for the horsepower, decent performance.

It is not enough to 'escort' the bombers, the escort mission must also be done at a low enough loss rate to allow continued operations otherwise it is just a matter of weeks or months before there aren't enough escorts left.

If the defender concentrates on the escorts, the inbound bombers can have a field day vs. now undefended ground assets (factories, marshaling yards, military bases etc).
Of course, the defender cannot concentrate all of its fighters against the inbound strike (bombers + excorts), since his fighters are short ranged (see RAF groups during the BoB). Meaning numerical advantage for the attacker.

 

[tomo pauk]

Actually, the RAF told Tizard 29-4-41 that they considered that the Hurricane was already at the end of any possible development, and that the Typhoon and tornado should take over as soon as possible. There seems to be this general memory loss, that the Hurricane and Defiant were designed around an expectation that they would only have to deal with bombers and the Me110; demanding instant reaction to the unexpected loss of France in 1940, and an immediate appearance of a fighter capable of taking on the Me109 over the occupied territories is somewhat unrealistic.

The Hurricane being designed before the Me 110 was known publicly? We can recall that Spitfire was a worldbeater when introduced, despite the (German) bombers being the conceivable target.
Escorting own bombers, whether France fights on or it is occupied, was not on the RAF's discussion table IIRC.

It was unavoidable, not acceptable; the Spitfire V was considered obsolete in 1942, but there was simply not the factory capacity (not just airframes, but engines as well) to turn out the more capable fighters; the Spitfire XII was built only because of a shortage of low-altitude Merlins, so the Griffon had to come into service before it was really ready.
Eisenhower wanted the Spitfire IX for Torch, but couldn't have them because there still wasn't (yet) a viable tropical air intake/filter.

Sending 3 men into jeopardy with Blenheim was accepted, but sending one in a Spitfire with extra internal fuel was a no-no.
Thanks for the Torch tidbit.

 

[pbehn]

What bombers would an RAF escort fighter escort? They all had weak defensive armament and liquid cooled engines, much more vulnerable than USA bombers in daylight.
The P51 was a magnificent escort fighter in fact really the only one that could do the job. Getting the P51B/C/D into service was a massive investment and also required large numbers of P47s and sometimes even spitfires on big ops. The British couldnt mount daylight raids on their own and after late 1943 would anyone want them to? The British and Americans both mounting daylight raids could be good in overwhelming defences and a disaster if two missions cross each others path.

 

[buffnut453]

They all had weak defensive armament and liquid cooled engines, much more vulnerable than USA bombers in daylight.

Really? So the Stirling, Halifax MkI and MkIII and Lancaster MkII had liquid-cooled engines? Who'd've thunked that?!!

As for "weak defensive armament", I'll accept that the .303 was less capable than a 50 cal but human-trained weapons, whether in a power turret or on a swivel mount, aren't the most accurate gunnery platform so the likelihood of a successful "kill" is probably about the same for either weapon. The RAF bomber's primary weakness was the lack of a ventral turret but in overall guns-per-aircraft and the employment method of those guns were about on par, if not ahead, of the US aircraft for much of the war...at least until the deployment of the B-17G.

 

[Edgar Brooks]

Sending 3 men into jeopardy with Blenheim was accepted,.

British military history is full of examples of the fighting men being sent into battle inadequately equipped, and it's still going on. When the idea of pilot back armour was first mooted, Sholto-Douglas fought against it, on the Spitfire, because, in his view, it was the fastest thing in the air, so only an inattentive pilot would allow someone to get behind him and shoot him down.

sending one in a Spitfire with extra internal fuel was a no-no.

Where's the advantage of putting a 27 gallon tank behind the pilot, which remains full of volatile fumes when "empty," and interferes with the pilot's rear/downward view, against hanging a 30 gallon tank under the fuselage, from where it can be dumped when empty?

 

[GrauGeist]

...The RAF bomber's primary weakness was the lack of a ventral turret but in overall guns-per-aircraft and the employment method of those guns were about on par, if not ahead, of the US aircraft for much of the war...at least until the deployment of the B-17G.

Well, let's see...

The RAF:
Lancaster I - (2) .303 nose turret, (2) .303 upper turret, (4) .303 rear turret
Halifax Mk.III - (1) .303 nose, (4) .303 dorsal turret, (4) tail turret
Stirling I - (2) nose turret, (2) dorsal turret, (4) tail turret
Lincoln I - (2) .50 nose turret, (2) .50 OR (2) 20mm dorsal turret, (2) .50 tail turret

The U.S.:
B-18A - (1) .30 nose, (1) .30 dorsal, (1) .30 ventral
B-17F(early) - (1) .50 nose, (2) .50 "cheek", (2) .50 dorsal turret, (1) .50 radio skylight, (2) .50 waist, (2) .50 ball, (2) .50 tail
B-24D - (3) .50 nose, (2) .50 dorsal turret, (1) .50 tunnel, (2) .50 waist, (2) .50 tail
B-25C/D - (1) .30 nose, (2) .50 dorsal turret, (2) .50 ventral turret, (2) waist (optional), (1) .50 tail
B-26B - (1) .50 nose, (2) .50 dorsal turret, (2) .50 waist, (2) .50 tail

In comparing 4 of the RAF's bombers against 5 of the U.S., I am having difficulty in seeing how the RAF was "on a par" with the U.S. heavy bombers. So I looked at the U.S. medium bombers and lo and behold...the medium bombers were comparable. (Except for the B-18, I just tossed that in for the heck of it!)
Bottom line, the U.S. heavy bombers were heavier armed, both in caliber and quantity, than their RAF counterparts.

With the exception of the Lincoln, the RAF bombers were woefully under-gunned, no matter how you look at it.

 

[stona]

In 1939/40/41 the British certainly were building bomber interceptors.

The reason the earlier versions of the Spitfire and Hurricane had eight machine guns was precisely to enable them to destroy bombers.

The reason the later versions and also later types like the Typhoon and Tempest were armed with cannon was the same. Fighter Command emerged from the RAF command Air Defence of Great Britain (ADGB). The clue is in the name.

As Sorley, who was in charge of the Operational Requirement Section at the Air Ministry when the Spitfire and Hurricane were being developed, later wrote.

"After much arithmetic and burning of midnight oil, I reached the answer of eight guns as being the number required to give a lethal dose in two seconds of fire. I reckoned that the bomber's speed would probably be such as to allow only one chance of attack, so it must be destroyed in that vital two second burst."

The move to cannon armament was to allow the destruction of the ever heavier armoured Luftwaffe bombers. All Britain's single seat fighters designed throughout the war were designed primarily as bomber interceptors. When they proved to be not very good in that role, or that role was no longer required, they took on other roles, sometimes with notable success.

For example in 1941 the idea of the Typhoon as a "cross Channel dogfighter" emerged, it was no more designed for that role (which it never undertook) than it was as a fighter bomber (which it certainly did).

Cheers

Steve

 

[tomo pauk]

...
Where's the advantage of putting a 27 gallon tank behind the pilot, which remains full of volatile fumes when "empty," and interferes with the pilot's rear/downward view, against hanging a 30 gallon tank under the fuselage, from where it can be dumped when empty?

Any fuel tank in any aircraft is full of volatile fumes when half or full empty, that goes also for the fuselage tank of the Mustang III/IV, and LE tanks of the later Spitfires (unless the fumes are purged by CO2 that some aircraft have had).

In case the 30 gal drop tank is attached under fuselage of the Spit V, and there is no extra fuselage fuel, max fuel is 30+84=114 imp gals. If the 29 gal tank is installed, max fuel can be 113 imp gals plus whatever is attached under fuselage (from 30 to 170 imp gals) - from 143 to 283 imp gals.

 

[tomo pauk]

What bombers would an RAF escort fighter escort? They all had weak defensive armament and liquid cooled engines, much more vulnerable than USA bombers in daylight.

The armament wasn't that weak, bar for the lack of belly turrets. RAF's LR fighters will be at 1st escorting the Wellingtons, Hampdens and Whitleys, until the 4-engined jobs take over.
The liquid cooled engines might provide troublesome when coupled with lower cruising altitude of non-turbo bombers (15-20000 ft vs 22-25000 for the US heavies), and then coupled with the German Falk gunners having it easier to hit something during the day than during the night. And/or have more accurate bursts of timed shells.
One can envision much more damaged aircraft due to the Flak.
On the benefit side, it would be much less wandering around the countryside and more bombs on the target, with steeper losses for the LW fighter arm.

The P51 was a magnificent escort fighter in fact really the only one that could do the job. Getting the P51B/C/D into service was a massive investment and also required large numbers of P47s and sometimes even spitfires on big ops.

The P-47 with bigger internal tanks (370 US gals; available from Spring of 1944) were also very capable to do the escort job. The debugged P-38s (later -J, the -L) were no slouch either. What the Merlin Mustang had was timing, a really important feature.
British introduced the bigger fuel tankage in their Spitfires and Tempests, but too late to matter (second half of 1944).

The British couldnt mount daylight raids on their own and after late 1943 would anyone want them to? The British and Americans both mounting daylight raids could be good in overwhelming defences and a disaster if two missions cross each others path.

The British did mount daylight raids, with significant losses, and eventually managed to push LW away from the coastline. They used just a trickle of bombers while doing that, and the LW have had options to either respond to the raids or not - not a way to do much the attrition to the LW fighter force.
Don't think it would be a disaster when two missions cross each other, both air forces have had the IFF systems.