Why did the British airforce adopted highly similar Hurricane and Spitfire at the same time?

[BiffF15]

Even without combat you can loose quite a number of aircraft just on routine flying over the course of 6 months. Especially on less than ideal airfields.
British figured you needed about 100% replacements every 6 months just for normal flying, does not count combat.
This was one reason that they only equipped two squadrons with Whirlwinds despite making 114 (?) of them. The extras were place in store for issue when accidents or combat occurred.
Turns out the Whirlwinds lasted longer than expected

The 120 number for Spitfires in service in Sept of 1939 vs the 250 in service in April also has to be seen in that light. They made a lot more than 130 Spitfires in those 7 months.
But you have to figure in the operational losses (accidents) and trying to build up a reserve. You need a lot more aircraft in storage to keep double the number of squadrons active without a rapid depletion in numbers once heavy combat starts.

With that number of planes in reserve, what was the reserve pilot pool like? It seems that if you had more pilots, you could stand up more squadrons, and bring greater numbers to bear during battle.
It just seems like that's a LOT of planes in reserve.

Cheers,
Biff

 

[Shortround6]

With that number of planes in reserve, what was the reserve pilot pool like? It seems that if you had more pilots, you could stand up more squadrons, and bring greater numbers to bear during battle.
It just seems like that's a LOT of planes in reserve.

Cheers,
Biff

I don't know.
It seems like some of the pilots went through several planes is a short period of time (others passed on with the first crash/encounter with the enemy).
The British may have issued new planes while damaged planes (past a certain point) were returned to repair centers/depots for either repair or salvage.
This may have changed at different times or when overseas. Replacement planes harder to get? more effort spent on repairs at local level.

 

[Wild_Bill_Kelso]

With that number of planes in reserve, what was the reserve pilot pool like? It seems that if you had more pilots, you could stand up more squadrons, and bring greater numbers to bear during battle.
It just seems like that's a LOT of planes in reserve.

Cheers,
Biff

Not necessarily given the rather ghastly attrition rates at that time. From what I understand, during the Battle of France RAF lost about 270 bombers (mainly Fairey Battles but also a fair number of Blenheims and some others), and at least 250 fighters (mostly Hurricanes) in about 10 days.

I've seen other estimates or numbers on the losses but regardless, life span of a front line military aircraft at this time was not much..

 

[tomo pauk]

If you want a fast monoplane you have to figure out how to rid of the struts and wires.

Consolidated P-30? Cantilever ... everything, even featured the retractable U/C and, later, a turbocharger.

 

[Zippythehog]

TLDR
So this may have been said. The Nazis wanted a war. The Empire, until Chamberlain was replaced, wanted peace. Typical of British industry, things were mainly cottage industries. The collusion of government and industry is a hallmark of National Socialism. The British did not focus on war material in a coordinated way until after September 1939.
This, associated with the, logical development in phases of the military specification (RAF) could suffice to be the answer.

 

[Wild_Bill_Kelso]

Everybody was evolving. The questions are how?

Maybe I am wrong but I really dislike the seaplane racer evolution theory. Yep they are monoplanes.
But they use thin airfoils and use Struts and wires to keep the wings from folding up.
They also are also not built to a big strength factor, most of those planes were only doing a bit over 2 Gs in a turn.
They also used the floats for fuel storage and cooling area.
They were very ingenious. They were lousy aircraft to base a fighter on.

Well those are fair points, hence my caution in choosing my words, i.e.: "...was at least to some extent inspired or influenced by" rather than "was directly developed from". Those seaplanes contributed to the development of engines and streamlining and control at high speeds and many other things. And yes they were supported with wires and struts, but it was clear to the designers involved that the second wing added too much drag if you really wanted to go fast.

A lot of the first generation monoplanes tried to keep the maneuverability of the biplanes.
Which was hard, The famous Hawker Fury had 252sq ft of wing and only weighed about 3600lbs.
The CR.32 had 238 sq ft and weighed (max) 4350lbs.
View attachment 699364
It was noted as being very strong and that was biplane advantage. For the upper wing to bend you had to bend the lower wing at the same time via the struts.

It was a great fighter. Also had some really weird and I'd say undesirable features like that nice torpedo looking thing in the center of the top wing- a fuel tank ready to burst and drench the pilot in petrol.

This thing was like trying to bend a Warren truss bridge. (patented in 1846)
If you want a fast monoplane you have to figure out how to rid of the struts and wires.
View attachment 699365

Wow! What the hell is that monstrosity! lol

203 sq ft, 4140lbs and using the same power engine, slower than the Italian Biplane. by around 10%.
View attachment 699362
295sqft , 4740lbs about 8mph faster (but at a higher altitude using a supercharged engine of 600hp) than the Italian fighter.
British didn't like it because the landing speed was too high

There were later and more advanced biplanes - CR 42 comes to mind - but the biplane design inherently limited top speed, (and to some extent range as well) and we know that speed ended up being one of the most important factors for WW2 fighters. They may not have necessarily known that in 1936.

It took a while to sort out the airfoils and the structures that would allow for a monoplane without outside struts/bracing wires.
Please note the 109 didn't get rid of the tailplane struts until the "F" model.
View attachment 699366

It was by no means an easy or simple transition from this

to this

But as we know, both of those successful fighters were designed and built by the same firm within a fairly short span of time.

 

[EwenS]

Not necessarily given the rather ghastly attrition rates at that time. From what I understand, during the Battle of France RAF lost about 270 bombers (mainly Fairey Battles but also a fair number of Blenheims and some others), and at least 250 fighters (mostly Hurricanes) in about 10 days.

I've seen other estimates or numbers on the losses but regardless, life span of a front line military aircraft at this time was not much..

I came across an Admiralty document from August 1939 which discussed the attrition reserves being sought by both the RAF and the RN.

The RAF were seeking reserves to cover monthly wastage rates of 70-90% per month for fighters (50% for flying personnel) and 70% for bombers (65% for flying personnel). The Cabinet had authorised the former but cut the latter back to about 40%.

 

[pbehn]

With that number of planes in reserve, what was the reserve pilot pool like? It seems that if you had more pilots, you could stand up more squadrons, and bring greater numbers to bear during battle.
It just seems like that's a LOT of planes in reserve.

Cheers,
Biff

This was covered in Bungays "Most Dangerous Enemy" which he described as creating a shortage of both men and machines. From memory the number of pilots per squadron was increased and the number of planes each squadron had was also increased but a squadron was still classed as 12 planes with pilots. Dowding was preparing for a war of attrition and his "system" of CAC relied on a squadron always being available sunrise to sunset every day. Twelve pilots with twelve planes would be lucky to survive the first morning at full strength without a reserve of planes, but you also need a reserve of pilots not only to replace any killed or injured but also to rotate and provide leave or cover for any sickness. As I remember it was around 18 pilots to a 12 man squadron. The situation was different with squadrons used as OTUs where pilots were supposed to train and then be introduced to the squadron proper in good time. This was where pilots with just a few hours (like 50) in proper fighters ended up in the battle itself.

 

[pbehn]

Not necessarily given the rather ghastly attrition rates at that time. From what I understand, during the Battle of France RAF lost about 270 bombers (mainly Fairey Battles but also a fair number of Blenheims and some others), and at least 250 fighters (mostly Hurricanes) in about 10 days.

I've seen other estimates or numbers on the losses but regardless, life span of a front line military aircraft at this time was not much..

When blitzkrieg started rolling in over airfields anything that wasnt airworthy refuelled and a pilot sat in it was lost along with all spares and ground crew.

 

[pbehn]

I don't know.
It seems like some of the pilots went through several planes is a short period of time (others passed on with the first crash/encounter with the enemy).
The British may have issued new planes while damaged planes (past a certain point) were returned to repair centers/depots for either repair or salvage.
This may have changed at different times or when overseas. Replacement planes harder to get? more effort spent on repairs at local level.

Some of the repair centres had an airfield attached, pilots in the BoB were told to land there if they knew their plane was damaged or would be by a forced landing. Though the piece I read didnt say if the pilot picked up a replacement there or was transported back to his squadron to get one there.

 

[Shortround6]

Consolidated P-30? Cantilever ... everything, even featured the retractable U/C and, later, a turbocharger.

Yes they did it. Lockheed had done it much earlier with the Vega transport (except the landing gear part)

Not stressed as a fighter
But they kept the same wing through the Orion and stuffed the landing gear into it. The whole Vega/Orion story is a tale of engine power, drag reduction and power.
Fitting wheel pants and a good (for the time) cowl was good for around 20mph?
With 300hp and dirty it was good for 155mph,
the same fuselage and same wing (moved to the bottom ) and clean (retracting gear) and 550hp was good for 226mph at a higher weight.
Clark Y-18 airfoil. It did take a number of years to add flaps one the last few built (added 400lbs to gross weight)

For perspective the late model Orion 9D

Using the same engine as the Boeing P-26

Could carry 6 passenger (plus pilot) only 9-10mph slower than the the P-26 while weighing over a ton more and using a wing almost double the size.
Granted it was not stressed for fighter maneuvers but somebody should have seen the writing on the wall.
The Lockheeds had been setting records for 5-6 years at this point and would continue for several more years.

 

[SplitRz]

Just to nip back to the original post title: '

highly similar Hurricane and Spitfire

'

I'm not sure that's an accurate assertion before we even delve into the 'why'. The two fighters shared a common engine. And shared the same armament, as per their specification. But any other similarity could be claimed by just about any other contemporary fighter (monoplane layout, single engine etc.)

They were very different in construction. Used different aerofoil sections. Had very different undercarriage and armament installation. They also had considerably different performance - as well as scope for development.... One came from the pen of a chief designer and team with a long pedigree in fighter design. The other more radical design from a much smaller operation which had been almost exclusively involved in seaplane and flyingboat design - and which up to this point, had only manage to design very mediocre fighter prototypes.

They really weren't 'highly similar' to my mind!

 

[Shortround6]

I Agree. About as similar as an F4U and and F6F.
Same engine, same armament, same radios.........................................................

 

[SaparotRob]

Consolidated P-30? Cantilever ... everything, even featured the retractable U/C and, later, a turbocharger.

I love the planes from the 30's.

 

[Wild_Bill_Kelso]

Definitely a lot less similar than the I-15 and the I-16!

 

[pbehn]

Even without combat you can loose quite a number of aircraft just on routine flying over the course of 6 months. Especially on less than ideal airfields.
British figured you needed about 100% replacements every 6 months just for normal flying, does not count combat.
This was one reason that they only equipped two squadrons with Whirlwinds despite making 114 (?) of them. The extras were place in store for issue when accidents or combat occurred.
Turns out the Whirlwinds lasted longer than expected

The 120 number for Spitfires in service in Sept of 1939 vs the 250 in service in April also has to be seen in that light. They made a lot more than 130 Spitfires in those 7 months.
But you have to figure in the operational losses (accidents) and trying to build up a reserve. You need a lot more aircraft in storage to keep double the number of squadrons active without a rapid depletion in numbers once heavy combat starts.

We are discussing plane numbers because Dowding and others referred to "Hurricanes" being deployed. In fact the numbers that mattered were Hurricane pilots, it was those that Dowding couldnt afford to lose. As per Tomo's post Hurricane and Spitfire production was an average of 100 per month in 1939, it rose through 1940 to a peak of around 500 per month of new aircraft in August 1940 with a similar number of damaged planes returned to service. As you say a lot of planes can be lost in normal operations, at the height of the battle, losses to all causes were almost incredible. Desite producing hundreds of new aircraft and repairing more the front line strength in numbers hardly increased at all and the actual strength in terms of experienced pilots went down. The situation was just the same on the other side of the channel, especially with bombers, Goerings bomber force went from the worlds most formidable to one with around 200 serviceable twin engined bombers with crews between the invasion of Norway and Sept 1940 in the BoB.

 

[Shortround6]

We are discussing plane numbers because Dowding and others referred to "Hurricanes" being deployed. In fact the numbers that mattered were Hurricane pilots, it was those that Dowding couldnt afford to lose. As per Tomo's post Hurricane and Spitfire production was an average of 100 per month in 1939, it rose through 1940 to a peak of around 500 per month of new aircraft in August 1940 with a similar number of damaged planes returned to service. As you say a lot of planes can be lost in normal operations, at the height of the battle, losses to all causes were almost incredible. Desite producing hundreds of new aircraft and repairing more the front line strength in numbers hardly increased at all and the actual strength in terms of experienced pilots went down. The situation was just the same on the other side of the channel, especially with bombers, Goerings bomber force went from the worlds most formidable to one with around 200 serviceable twin engined bombers with crews between the invasion of Norway and Sept 1940 in the BoB.

Just trying to reconcile the numbers available with the numbers produced.
Very little doubt that Dowding did the right thing.

 

[pbehn]

Just trying to reconcile the numbers available with the numbers produced.
Very little doubt that Dowding did the right thing.

I agree and despite being 100% correct on almost everything he made enemies of the clueless who remained clueless and forgot how really clueless they were.

 

[SplitRz]

I agree and despite being 100% correct on almost everything he made enemies of the clueless who remained clueless and forgot how really clueless they were.

The Dunning-Kreuger effect was alive and well in many military circles at the time!

 

[GrauGeist]

The Japanese Army had the KI-10 (biplane) entering into service in 1935, the KI-27 (monoplane) entered service in 1937.
The KI-43, which entered service in 1941, was developed from the KI-11/KI-12 (monoplane) which was being tested in 1936. The KI-27 also came from the KI-11/12, by the way.

The Japanese Navy had the A4N (biplane) which entered service in 1936. The A5M (monoplane) entered service in 1937 and was followed by the A6M, which entered service in 1940.

So it's hard to nail down a distinct 1st, 2nd, 3rd, etc. generation monoplane during the span between biplanes and jets.