The actual quote is a bit more blood-thirsty, with Malan saying something bout how he liked the moral-dampening effect of sending the damaged bomber home with the injured crew shot to ribbons or coughing their lungs out. Something like that anyway.
Impact of fully adopted and reliable 20mm in BoB
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True, but you're looking at the "not" data - the aircraft that were not shot down. Many German bombers went down after a single burst, because a de Wilde incendiary hit the right spot and set them alight, or an AP round found an oxygen tank (instant disintegration), or killed the pilot. Some RAF night bombers came home with more than twenty hits by MG-FFM minengeschoss ammunition, whereas some B-17s went down after one shell in the cockpit.
On another point, all the Luftwaffe bombers in the Bob excepting the Do17s had liquid-cooled engines, which meant they were very vulnerable to even .303 ball ammo. One hit in each radiator and they had about five minutes before the engines seized. A lot of Luftwaffe bombers lost over Britain in 1940 took minor flak damage, which led to engine failure, which led to the bomber being forced to crash-land. Bullet placement is much more important than simply spraying the target, a matter the aces realized and meant they aimed for the engines and the cockpit. The RAF standard of eight .303s sprayed a lot of bullets, which gave the average pilot a better chance of hitting the spots the aces aimed for. The cannon would have fired less rounds, so less chance for the average pilot to hit the right spot. And, even with 20mm HE shells, you still had to hit the right spot to bring a bomber down.
In theory, any Spitifre after the V with the universal wing could carry four Hispanos. The Spitfire VC was intended to go for four Hispano cannons as standard, and the original batch sent to Malta in 1942 did include four-cannon Spitfires, but the pilots on Malta preferred two Hispanos and four .303s because it was lighter, which meant the Spits climbed better, and rate of climb was all important over Malta. They also only faced twin-engined Ju88s and three-engined Savoias, so two Hispanos were enough punch to get the job done. If they had faced something tougher like B-17s then they probably would have needed four Hispanos, but the Luftwaffe failed to make a real strategic bomber as good as the B-17.
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Admiral Beez
Major
IDK, Germany could follow Prussia's example, crush the French into submission, and then completely withdraw from France once they agree to terms. With France no longer at war or under occupation, but instead the French people are left to enjoy their baguettes, fine wines and soft cheeses; do the British people still have sufficient beef with Germany to carry on?
IMO, once the French have surrendered and the Germans have withdrawn, the British people, Parliamentary opposition and even FDR may be pushing for Churchill to call it a day - no one wants Bolshevism to spread, so many may be cheering Hitler on. Of course this wouldn't bode well for Hitler's Untermensch, nor Japan's expansionist plans. Maybe someone wants to try this out in the What'if forum?
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Oh dear, history lesson in the offing!
The V7360 aircraft was built by Hawker in response to the Air Ministry's four-cannon fighter requirement, and the cannon installation was first sketched in 1934. V7360 is supposed to have made its first flight in four-gun form in March 1936. The design was tendered to the Air Ministry in April 1936, with four Oerlikons, and rejected, because the Air Ministry had already decided the Hispano was a better option, and because the cannon required a completely different wing design (the box wing), which would have disrupted Hurricane production. Hawker then continued developing V7360 as a research prototype with the Air Ministry's approval. The box wing design used on V7360 replaced the spar wing of the Hurricane I for the Hurricane IIC's four-cannon design, which was one reason why the Hurricane IIC went into service so smoothly - the new wing design had already been proven.
L1750 was a much simpler requirement, to test whether a Hurricane I with the standard spar wing could be fitted with cannon. Because the cannon barrels were too big to pass through the leading spar without major cutting and reinforcing, the idea was to test two underwing gunpods. Such an improvisation offered a quick way to switch a number of existing Hurricane Is into cannon-carrying Hurricanes. Oerlikons were used for the test aircraft because they were available, whereas Hispanos were not. The result was slower and less manouverable than the ordinary Mk I, so did not pass muster. The idea did later lead to the 40mm anti-tank version, the Hurricane IID. L1750 was tested at North Weald and was still attached to 151 Squadron when the BoB started, languishing in a hanger there as no-one wanted to fly a slower Hurricane. It wasn't until F/Lt Smith joined the Squadron on 19th June 1940, saw L1750 and decided to give it a go that it was used operationally. Smith described himself as "a bit of a gun buff" and wanted to see what the cannon could do!
The Fwench had already effectively surrender. Hitler was not going to withdraw from France because he needed the resources France offered, especially their steel production. American Naziphiles like Ambassador Joseph Kennedy were already trying to convince FDR that Britain was finished. But then Hitler wasted several weeks after Dunkirk because he thought Churchill was going to come asking for terms, which was several weeks the RAF used to rebuild their strength. Hitler really did have no idea what to do after conquering France, he was so convinced that the British would just sue for peace that he didn't actually have a plan for what to do next. It was wishful thinking characteristic of Hitler's inability to plan longer term strategies. When Churchill told him to go get stuffed (and the Royal Navy's attack on the French fleet at Mers El Kebir finally convinced Washington that Churchill meant business), the Germans quickly cobbled together a plan to invade Britain. That was a no-go because the Kriegsmarine had been caned by the Royal Navy in Norway, and couldn't provide the landing craft or naval backup to get the Wehrmacht across the Channel. Goering said the Luftwaffe would solve the problem, but when they too failed (due to those RAF eight-.303-gun fighters), Hitler decided to starve the British out with a U-boat blockade, and turned to attack Soviet Russia instead.
The general narrative sounds about right but I've never come across anything that would indicate a (nonsensical in my opinion) substitution of the Hispanos with Oerlikons.
A&AEE trials (24 Nov 1939) of V1750 clearly show Hispano guns.
A&AEE trials (4 Aug 1940) of V7360 clearly show Hispano guns.
EDIT: date/serial no. typos
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Just to give an idea of why the .303 was probably better for the average pilot than cannons, consider the case of Flying Officer Joe Average shooting at a Dornier 17Z. Lets assume the Dornier has dropped his bombs and the pilot has selected max boost to escape back to his French trollop. That means the Dornier is doing around 250mph. F/O Average has got into position to make a beam attack, aiming for the cockpit. A beam attack is good because he has the whole length of the fuselage to spray, and hitting from the sides negates any cockpit armour protecting the crew from attacks from the rear. But, imagine you're standing by a highway and cars are whipping by at 50mph. They're there and gone in a flash, and that's just 50mph, whereas the Dornier is going five times that speed.
Now, if F/O Average fires even a microsecond too soon, the first rounds fired will pass harmlessly in front of the bomber. At 250mph, the Dornier will fly through the aiming spot in 0.144 of a second, meaning if the first rounds pass just in front of the bomber, only those rounds arriving in that following 0.144 of a second have a chance of hitting the airframe. With eight .303s, each firing at 1150rpm, that's about 3 rounds of .303 per gun, or 24 possible hits, spread along the length of the fuselage.
Now, with the slow firing MG-FF, if those first rounds just miss, that's a possible one more chance of a hit per gun before the Dornier is past the aiming point, and it's going to be back in the empty tail, far away from the vulnerable crew, fuel tanks or engines.
If you switch the aircraft and it's a Bf109E4 jock shooting beam on at a Hurricane or a Spitfire doing 300mph, and the first 20mm round pass just in front of the target's spinner, then the RAF fighter will have passed through the aiming point in less than 0.075 of a second, before the next 20mm shells arrive 0.11 seconds after the first, passing harmlessly behind the fighter. Positions reversed and the RAF fighter will still score several .303 hits on the ME. A simplified case which assumes the pilots don't adjust their flight to follow their targets, but it shows the difficulty of hitting high-speed targets. And several hits with the spray-n-pray .303s beats no hits with a 20mm.
Now, if F/O Average fires even a microsecond too soon, the first rounds fired will pass harmlessly in front of the bomber. At 250mph, the Dornier will fly through the aiming spot in 0.144 of a second, meaning if the first rounds pass just in front of the bomber, only those rounds arriving in that following 0.144 of a second have a chance of hitting the airframe. With eight .303s, each firing at 1150rpm, that's about 3 rounds of .303 per gun, or 24 possible hits, spread along the length of the fuselage.
Now, with the slow firing MG-FF, if those first rounds just miss, that's a possible one more chance of a hit per gun before the Dornier is past the aiming point, and it's going to be back in the empty tail, far away from the vulnerable crew, fuel tanks or engines.
If you switch the aircraft and it's a Bf109E4 jock shooting beam on at a Hurricane or a Spitfire doing 300mph, and the first 20mm round pass just in front of the target's spinner, then the RAF fighter will have passed through the aiming point in less than 0.075 of a second, before the next 20mm shells arrive 0.11 seconds after the first, passing harmlessly behind the fighter. Positions reversed and the RAF fighter will still score several .303 hits on the ME. A simplified case which assumes the pilots don't adjust their flight to follow their targets, but it shows the difficulty of hitting high-speed targets. And several hits with the spray-n-pray .303s beats no hits with a 20mm.
V7360 might have been lugging Hispanos in late 1940, but there were no Hispanos available when L1750 was originally trialed in 1939, and definitely none in 1936 when V7360 first flew with four cannon. I'm also curious as to how you are so sure the cannon are Hispanos given that L1750's guns were wrapped up in gunpods, and V7630's were contained inside the wings, so unless you're saying you can definitely state for a fact, from the barrels alone, that those cannon could only be Hispanos, I'm going to suggest you think again.
The A&AEE pic of V7360 in July 1940, after fitting with a three-blade, constant speed prop, shows the cannon barrels as unshrouded. The pic does not show the classic hexagonal muzzle nuts typically seen on Hispanos, nor the recoil spring that is also usually wrapped around the barrel. If you look at other early Hispano mounts, such a those on the early Hurricane IICs, there is a slim root shroud that extends almost a foot from the leading edge of the wing to cover that spring before you get bare barrel. The root shrouds on V7360 are both shorter and fatter, implying the spring they cover is a different in shape to that of the Hispano. The barrels are also simply too long for Hispanos. You can search for a pic of BE500, an early IIC intruder, and you will see the root shrouds and barrels are different.
I have seen a late pic of L1750 when the aircraft was trialed with Hispanos when developing the pneumatic cocking mechanism for the IIC, and you can again see that both the barrels are shorter and that the opening at the front of the gunpods for the barrels is larger than the barrels by quite an amount, giving a loose look to the fitting. Earlier pics of L1750 show the opening is tight to the cap of the recoil spring on the longer Oerlikon barrels.
Sorry, edited my post too late. Trial of V1750 was 24 Nov 1939.
I can't visualize what you're trying to describe, but I've seen enough photos/diagrams of Hispanos in my day. Here are some photos.
Top (and enlarged centre) are from the L1750 trials 24 Nov 1939.
Bottom is a Hawker photo dated April 1939.
The photos of V7360 aren't clear but there is a good one of the early front mounting unit, which certainly does look odd and the design was shown to be faulty.
As far as I know V7360 was part of Hawker Contract No. 62305/39 (delivered 2/7/40 - 5/2/41) so I doubt it was flying with four cannon in 1936.
Despite all this, the wording in the trials spell out exactly what type they were.
EDIT: serial no. typos
I can't visualize what you're trying to describe, but I've seen enough photos/diagrams of Hispanos in my day. Here are some photos.
Top (and enlarged centre) are from the L1750 trials 24 Nov 1939.
Bottom is a Hawker photo dated April 1939.
The photos of V7360 aren't clear but there is a good one of the early front mounting unit, which certainly does look odd and the design was shown to be faulty.
As far as I know V7360 was part of Hawker Contract No. 62305/39 (delivered 2/7/40 - 5/2/41) so I doubt it was flying with four cannon in 1936.
Despite all this, the wording in the trials spell out exactly what type they were.
EDIT: serial no. typos
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The Basket
Senior Master Sergeant
- 3,712
- Jun 27, 2007
What time frames we talking about?
My issue would be that having a 20mm cannon is fine. But it backfires when it has to be designed into an aircraft.
So if you design Spitfire with 20mm cannon it probably ain't a Spitfire no more and you turn it into a Typhoon instead.
So to get the bag rolling, in 1935 you have to have a 20mm cannon ready to go. And your aircraft designs ready to accept it. So I don't see it. Timeframes are wrong.
Unless you magic wand it, the timeframes don't give a British single engine fighter in 1940 with cannon. And if an autocannon did exist, it would be a burden on the single engine designs that had to lug it.
Anyhoo weren't the cannon earmarked for Whirlwinds? Apart from the Oerlikon was there any other autocannon around in 1935 which could have been used? Off the shelf?
From a purely production and testing and installation point of view I ain't feeling it. Without combat experience advising otherwise, I can't see it.
If in 1935 I was advised i got to carry 20mm cannon then I have to go twin engined as a bomber destroyer and I design the Me 110. I ain't building a single engine fighter for that role.
My issue would be that having a 20mm cannon is fine. But it backfires when it has to be designed into an aircraft.
So if you design Spitfire with 20mm cannon it probably ain't a Spitfire no more and you turn it into a Typhoon instead.
So to get the bag rolling, in 1935 you have to have a 20mm cannon ready to go. And your aircraft designs ready to accept it. So I don't see it. Timeframes are wrong.
Unless you magic wand it, the timeframes don't give a British single engine fighter in 1940 with cannon. And if an autocannon did exist, it would be a burden on the single engine designs that had to lug it.
Anyhoo weren't the cannon earmarked for Whirlwinds? Apart from the Oerlikon was there any other autocannon around in 1935 which could have been used? Off the shelf?
From a purely production and testing and installation point of view I ain't feeling it. Without combat experience advising otherwise, I can't see it.
If in 1935 I was advised i got to carry 20mm cannon then I have to go twin engined as a bomber destroyer and I design the Me 110. I ain't building a single engine fighter for that role.
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Kevin J
Banned
Blohm & Voss BV 138 - WikipediaThe LW only had a few dozen Diesel engined aircraft and for some reason they were very prone to engine fires.
Flashpoint of Avgas is -40 centigrade, flashpoint of diesel is +60 centigrade, self ignition point of Magnesium is +473 centigrade.
For those people from primitive countries that still use Ye Olde British Goat measurements you will have to use google to convert Centigrade to Fairyheights.
The Luftwaffe's High-Flying Diesel-Powered Bomber
Have a read.
buffnut453
Captain
There's simply no way that V7360 was flying with cannon (or any armament, for that matter) in 1936. V7360 was part of the fourth production block of Hurricane MkIs built by Hawker Aircraft Ltd at Langley to Contract 62305/39 (ie the contract was let in 1939). Deliveries commenced on 2 July 1940 and were completed on 5 February 1941. In short, Hurricane V7360 didn't exist in 1936.
It seems that V7360 went straight to A&AEE at Boscombe Down where it was used in cannon testing. According to "The Secret Years: Flight Testing at Boscombe Down, 1939-1945" it was fitted with four Hispano cannons.
The pilot was a more important component. They didn't all fly Spitfires in the BoB (Lock, McKellar and I think Gray did).
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Those pilots were not operational pilots (except in some films made later). They were supposed to continue and finish training with their squadron, which became impractical within 11 and to some extent 12 Groups during the BoB.
It's a problem that led to the much maligned stabilisation system, whereby squadrons in other Groups gave up their experienced pilots to squadrons in 11 Group to make up their losses and received new non-operational pilots in return. This led to B Class squadrons, some of which could only field a Flight of operational pilots, and C Class squadrons, which were not really operational in a meaningful way. Of course, all these pilots and squadrons are still counted in Fighter Command's strength, which has given rise to another great myth, that the Command was stronger at the end of the Battle than at the beginning.
I blame Stephen Bungay's popular and populist history of the Battle!
Edit: I do blame Bungay, but only for slavishly repeating assertions made in the Air Ministry's infamous Battle of Britain pamphlet (the one that mentioned neither Dowding, nor Park) without doing his job as a historian.
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fastmongrel
1st Sergeant
Neither link disproves anything I said.
I was just saying that is the statistics, nothing to stop a Hurricane pilot becoming an ace or a spitfire pilot being lost on his first day.
I was saying why some felt the need for cannon which was a perception not a complete reality.
Kevin J
Banned
A production run of 297 is not a few dozen but a few hundred. Pre war problems with diesel engines is not the same as having permanent problems with diesel engines.
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The bombers had shots spread all over them because of the reasons already mentioned, the pilots weren't skilled enough to aim at specific points but instead just aimed at the big black blob in front of them, the gun harmonization was the ''Dowding Spread'' which was 12 foot by 8 foot at 360 meters which didn't help concentrate the fire.
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