WW2 with no Spitfire - Hurricane being primary interceptor

[Aozora]

With greater number of aircraft available, more Hurricanes can be flown as top cover, reducing the risk of being bounced.

Just means there would have been more Hurricanes to bounce.

 

[Glider]

Unfortunately all that will happen would be that more Hurricanes would be lost. The Me 109 was a much better fighter and the RAF knew it

 

[altsym]

Werner Schröer, once said about the P-40's, they were "bunches of grapes", because he found them so easy to pick off. I imagine it would be no different with nothing but Hurricanes flying around.

 

[RCAFson]

Just means there would have been more Hurricanes to bounce.

????

The problem typically stemmed from the fact that there wasn't enough Hurricanes available to provide an adequate top cover; IE get above the usual attack altitudes of the 109s. Typically the Hurricanes that were lost never saw their attackers.

 

[OldSkeptic]

To give Camm his due Bristol was off by about 30mph on it's prediction for the Beaufighter. The Boffins at the RAE were handing out some bad formulas when it came to thick wing drag at high speed.

Yes and that was part of the genius of the Supermarine team, Mitchel completely ignored that and went for a thin wing ... and was 100% correct.

Camm compounded his mistake in the Typhoon, went for a thick wing again, finally woke up and re-winged it to make the superb Tempest.

 

[OldSkeptic]

With greater number of aircraft available, more Hurricanes can be flown as top cover, reducing the risk of being bounced.

Not with its maximum altitude it couldn't. Sit there and watch the 109s sail well above you....

 

[DonL]

@ RAFson

what are your expected performance data's for a "modified" Hurricane?

I was often criticized for my FW 187 data's although they are basing on official FW data's from FW engineers and official FW specifications.

Do you realy expect that a Hurricane can perform up to 600km/h? She only reached 547km/h as fighter with the Merlin XX and I have very seriously doubts that you can re-engineer an a/c from aerodynamics that you can peak the performance to this level with near the same engine performance.

You should be aware that both the Bf 109F and the FW 190A3 were clearly faster then 600km/h with normal 30min combat power.
Both were around 630km/h with normal 30min combat power.
So a modified Hurricane must be at the 600km/h region to be somewhat competitive, otherwise she is very easy meat as reality has shown.

What is your expected performance, basing on which technical arguments?

 

[OldSkeptic]

Another factor everyone seemsto be ignoring, the Hurricane was not well set up for mass production. All those tubes and fabric...

The reason it got a head start on the Spitfire in terms of production was that the British aircraft industry was used to that type of construction, so there was little learning curve (after all the Hurricane was really just a single winged Fury).

But when they got the shadow factories up and running, monocoque construction was far easier to mass produce (especially with low skilled labour) once you set up all the jigs and equipment.
Yes, the Spit's wing was complex, but again that was a setting up issue. Once they got all the capital equipment in place they were throwing them out.

The Hurricane's wings, the second ones after they re-winged it with metal wings (the original fabric ones being less than successful) were easier to manufacture, but the body was harder.

Aerodynamically it was a full generation behind the 109 and Spit and because of that it didn't matter what power you put into it to get to go much faster.

To get much above 350mph, you need to re-wing it and to aid mass production (and make it faster, stronger and less vulnerable to damage) you need to re-do the fuselage to a moncoque design.
Basically a whole new plane. You could call it the Hurrifire, or the Spitcane.

 

[RCAFson]

Not with its maximum altitude it couldn't. Sit there and watch the 109s sail well above you....

The Hurricane II and the 109E had approximately the same service ceiling of ~36000ft, as did the Merlin45 powered Hurricane. The 109F had a better ceiling but if they fly that high, they are only going to be engaging the Hurricane top cover.

 

[wuzak]

Was there actually ever a Merlin 45 Hurricane? Or was it just projected?

 

[RCAFson]

Another factor everyone seemsto be ignoring, the Hurricane was not well set up for mass production. All those tubes and fabric...

The reason it got a head start on the Spitfire in terms of production was that the British aircraft industry was used to that type of construction, so there was little learning curve (after all the Hurricane was really just a single winged Fury).

But when they got the shadow factories up and running, monocoque construction was far easier to mass produce (especially with low skilled labour) once you set up all the jigs and equipment.
Yes, the Spit's wing was complex, but again that was a setting up issue. Once they got all the capital equipment in place they were throwing them out.

The Hurricane's wings, the second ones after they re-winged it with metal wings (the original fabric ones being less than successful) were easier to manufacture, but the body was harder.

Aerodynamically it was a full generation behind the 109 and Spit and because of that it didn't matter what power you put into it to get to go much faster.

To get much above 350mph, you need to re-wing it and to aid mass production (and make it faster, stronger and less vulnerable to damage) you need to re-do the fuselage to a moncoque design.
Basically a whole new plane. You could call it the Hurrifire, or the Spitcane.

The Spitfire had a far (far far! - 4 million pounds for the Bromwich plant alone) higher level of investment on production than the Hurricane and from 1942 onward a higher production priority, yet by August 1944 when production of the Hurricane was terminated total numbers produced were similar for both , 14600 Hurricanes and ~17000 Spitfires. If Canadian Hurricane production had continued at it's peak pace, instead of being terminated in early 1943 then the number would have been very close. The speed and ease which Canada set up production of the Hurricane suggests that it was easy to build, and as others have mentioned it was also license built in Belgium and Yugoslavia, suggesting that it was relatively easy to put into production.

 

[RCAFson]

Was there actually ever a Merlin 45 Hurricane? Or was it just projected?

The 45 was trialled on a Hurricane I airframe and the performance was well documented at Boscombe Down.

 

[Shortround6]

The Hurricane II and the 109E had approximately the same service ceiling of ~36000ft, as did the Merlin45 powered Hurricane. The 109F had a better ceiling but if they fly that high, they are only going to be engaging the Hurricane top cover.

service ceiling is useless, A single plane can fly straight and level with a small margin of extra power. Operational ceiling is 2-3,000ft lower. The altitude at which a small formation can fly or perhaps bounce from. Actual combat involving much in the way of turns or maneuvers is going to be several thousand feet below that.

After the 109s shoot down the top cover several times in row they will start getting through to the strike aircraft as the British run out of planes or pilots.

Even if the Hurricane is that much easier to build the Germans can make bullets faster than the British can make cheap Hurricanes and expensive pilots.

 

[RCAFson]

@ RAFson

what are your expected performance data's for a "modified" Hurricane?

I was often criticized for my FW 187 data's although they are basing on official FW data's from FW engineers and official FW specifications.

Do you realy expect that a Hurricane can perform up to 600km/h? She only reached 547km/h as fighter with the Merlin XX and I have very seriously doubts that you can re-engineer an a/c from aerodynamics that you can peak the performance to this level with near the same engine performance.

You should be aware that both the Bf 109F and the FW 190A3 were clearly faster then 600km/h with normal 30min combat power.
Both were around 630km/h with normal 30min combat power.
So a modified Hurricane must be at the 600km/h region to be somewhat competitive, otherwise she is very easy meat as reality has shown.

What is your expected performance, basing on which technical arguments?

The IIa was good for for 551 km/h and i expect that it could make about 565 km/h with a cleaned up airframe and the MXX. A modded XX with SC gearing optimized for higher altitude would probably do a bit better at high altitude while one fitted with a Merlin 24 would probably make about 560-570 km/h at ~3km.

Here's what the Hurricane IIb can do with a Merlin XX at 3000rpm/9lb boost:

http://www.wwiiaircraftperformance.org/hurricane/hurricane-II-raechart-level.jpg

now lets imagine the same aircraft with a Merlin 24.

and then with a Merlin 60 series. The 60 series will give another 300-500 hp at altitude while the 24 will give 300-400 more at low altitude.


I'll crunch some numbers and reply later.

 

[wuzak]

The IIa was good for for 551 km/h and i expect that it could make about 565 km/h with a cleaned up airframe and the MXX. A modded XX with SC gearing optimized for higher altitude would probably do a bit better at high altitude while one fitted with a Merlin 24 would probably make about 560-570 km/h at ~3km.

Here's what the Hurricane IIb can do with a Merlin XX at 3000rpm/9lb boost:

http://www.wwiiaircraftperformance.org/hurricane/hurricane-II-raechart-level.jpg

now lets imagine the same aircraft with a Merlin 24.

and then with a Merlin 60 series. The 60 series will give another 300-500 hp at altitude while the 24 will give 300-400 more at low altitude.


I'll crunch some numbers and reply later.

I'm sorry, but the 551km/h (342mph) is marked on the graph as a calculated figure. That is, it is not a measured test figure.

Hurricane IIs that were tested (admittedly a IIb with 12 x 0.303") were only able to reach 330mph (531km/h).

Your projected performance, therefore, seems rather hopeful.

 

[altsym]

Paper airplanes. You can put a big enough motor with a prop onto a brick and it'll fly. Doesn't mean its going to perform.

 

[Aozora]

@ RAFson

what are your expected performance data's for a "modified" Hurricane?

What is your expected performance, basing on which technical arguments?

We've had these questions before with the following answer: Projected improved Hurricane performance

I don't buy it: to modify the Hurricane sufficiently to develop even Spitfire V like performance figures would mean making changes which would have negated some of the expected performance gains. For one thing the radiator housing would have had to be considerably larger to cater for the larger radiator area plus intercooling required by the Merlin 60 series; without some careful work the added bulk and drag of the installation would have knocked off several mph (another possibility would be to mount the radiators under the nose, or split the radiators and mount them under the wings).

The IIa was good for for 551 km/h and i expect that it could make about 565 km/h with a cleaned up airframe and the MXX. A modded XX with SC gearing optimized for higher altitude would probably do a bit better at high altitude while one fitted with a Merlin 24 would probably make about 560-570 km/h at ~3km.

Here's what the Hurricane IIb can do with a Merlin XX at 3000rpm/9lb boost:

http://www.wwiiaircraftperformance.org/hurricane/hurricane-II-raechart-level.jpg

now lets imagine the same aircraft with a Merlin 24.

and then with a Merlin 60 series. The 60 series will give another 300-500 hp at altitude while the 24 will give 300-400 more at low altitude.

I'll crunch some numbers and reply later.

From Mason Hawker Aircraft since 1920 pages 299-300:

http://www.wwiiaircraftperformance.org/hurricane/z3564.html
http://www.wwiiaircraftperformance.org/hurricane/z3564-weights.jpg

Numbers crunched: 330 mph @ 25,000 ft for Mk IIB Z3564 @ 7,397 lbs

 

[wuzak]

Aozora, those numbers seem to confirm RCAFson's 342mph figure for the IIA. However, it also shows the IIB at 340mph, only 2mph slower.

Hurricane Mk II Performance shows a IIB with a top speed of 330mph @ 25,000ft.

 

[Shortround6]

A modded XX with SC gearing optimized for higher altitude

What gearing optimized for higher altitude?

the 9.49 gear used in the Merlin XX was the highest gear ratio used in a production single stage Merlin. Impeller tip speed was already 1272 fps.

The Higher the gear ratio the more power you use to drive the supercharger. 25-35% of the power going into the supercharger winds up as heat in the intake charge. Using a higher gear will increase the intake temperature which lowers the density of the intake charge and it starts to get a bit self defeating. There were TWO experimental engine set-ups that used a higher gear ratio of 10.5, one used an inter-cooler somewhat like the Merlin 60 series and the other used water injection.

would probably do a bit better at high altitude while one fitted with a Merlin 24 would probably make about 560-570 km/h at ~3km.

Not without strapping a rocket to it. Your source says 308mph (calculated) flight tests says 294mph. I averaged to 300mph (to make things simple, sue me for the 1mph) and used 1200hp. using the cube rule 1600hp gets you to 330mph. 570kph (353mph) requires about 1900hp. This is with NO CHANGE in drag. Is a retracting tail wheel and a trick mirror going to be worth bigger radiators? A heavier prop and more ballast in the tail (or does the retract system weigh enough ?) .

Maybe I screwed up the calculation?

and then with a Merlin 60 series. The 60 series will give another 300-500 hp at altitude while the 24 will give 300-400 more at low altitude.

Talk about throwing good money after bad

 

[Aozora]

Aozora, those numbers seem to confirm RCAFson's 342mph figure for the IIA. However, it also shows the IIB at 340mph, only 2mph slower.

Hurricane Mk II Performance shows a IIB with a top speed of 330mph @ 25,000ft.

Mason notes that his figures are based on aircraft checked at the factory, rather than RAE figures:

giving 342 mph as a baseline, and pretending the performance gains would have similar to those of the Spitfire IXB over the Spitfire V (doubtful) the Hurricane Mk VII with Merlin 61 might have reached a maximum speed of c. 380 mph and maximum rate of climb of c. 3,300 ft/min, service ceiling @ 38-39,000 ft - roughly what a Spitfire Mk V was capable of.