Improvements to the Spitfire

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tomo pauk

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Apr 3, 2008
One of the icons of ww2 air warfare. What should/could be improved on it, the earlier the better?
 
Would/could the cooling arrangement used on he P 51 reduce drag and allow space for fuel in the wings?
 
Would/could the cooling arrangement used on he P 51 reduce drag and allow space for fuel in the wings?

It probably would in both accounts.

Speeding up the Spitfire, at least between Mk.I and Mk.VI marks, might involve replacing the two-per-cylinder exhaust stacks with one-per-cylinder. Earlier installing of one of the pressure-injection carbs, or fuel pumps, couls also help adding some speed, 8-10 mph per this test (link). These two things were already in the P-39/40/51, Spitfire got them with Mk.VII on IIRC. (one might stipulate on similarly outfitted Hurricane).
Another thing that might come in handy would be the earlier introduction of fully retractable covered undercarriage, that was introduced with Mk 21 in series. The Mk VII was the 1st to feature retractable tailweheel.
 
With the requisite crystal ball ... metals ailerons would have been a relatively easy one from the beginning.
 
On a more serious note, earlier (as in 1940 early) introduction of fuel injection, which would also probably increase endurance/range slightly, and possibly speed.
Earlier introduction of metal-skinned control surfaces, especially ailerons.
Earlier introduction of jettisonable canopy.
Fully self-sealing and armour protected fuel tanks.
And as previously mentioned, effective, reliable, heavier armament, either cannon or .50 cal.
 
Agree with fuel injection, however early flight testing with carbureted Merlin engines might have highlighted the negative G fuel starvation problem which was solved with "Miss Shilling's orifice"
 
Sack Leigh Mallory. It is impossible to evaluate the spitfires performance by loss ratios or combat reports when a commander is so careless with his men and their aircraft.
 
Wasn't Mark III that improvement you're asking for ?

Indeed, the Mk.III was 'right on the money', showing how the small details can make a lot.
It did featured fully covered U/C (similar to the prototype on main wheels), and the bullet proof windshield was internal type, rather than external that again cost some speed. The wing tips were clipped on the Mk III so the wing was with a smaller span area, probably earned there a few mph. Being the prototype, it's fit finish was probably excellent
Too bad it was not further pursued with Merlin 45 (so it doesn't not draw the Merlin 20s needed for bombers), with pressure inject carb (no problem with negative G, less losses than with float type) and 'single' exhaust stacks, reliably beating 400 mph mark even when in mass production.
 
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One rather obvious improvement would be to the windscreen. It was too steep by a more than a little and was a source of drag that could have been improved easily. I also think fully enclose wheelwells would have been easy and might have helped a few knots, too, for almost no penalty.

And retract the tailwheel much sooner than they did.
 
Back to the Mk.III - it also featured the increase in fuel tankage by 15.5 imp gals, for almost 100 imp gals total. On cruise, it allows for another 15-20 minutes, or another 80-100 miles flown.

The windescreen on the Spitfire was at 35 deg, on P-51 it was on 31 deg, and Fw 190 was at 22 deg (!!), per Lednicer's analysis.
 
Indeed, the Mk.III was 'right on the money', showing how the small details can make a lot.
It did featured fully covered U/C (similar to the prototype on main wheels), and the bullet proof windshield was internal type, rather than external that again cost some speed. The wing tips were clipped on the Mk III so the wing was with a smaller span area, probably earned there a few mph. Being the prototype, it's fit finish was probably excellent
Too bad it was not further pursued with Merlin 45 (so it doesn't not draw the Merlin 20s needed for bombers), with pressure inject carb (no problem with negative G, less losses than with float type) and 'single' exhaust stacks, reliably beating 400 mph mark even when in mass production.

Overall agree, though the 'standard wing' ended up being preferred, with wings clipped as required. Another improvement was a better radiator, long a major drag issue (compared to a Mustang or a Mosquito). The Mk III would have been a very good match for the 190A's of the time.

Supermarine did propose (in late '43 from memory) to change the Spit to have a Mustang like radiator system and estimated it to add 25+mph, but MAP canned it due to production desruption and RR just kept coming up with more power.

The other major innovation was more range, this meant jamming more fuel into it and many good prototypes were developed. But once Portal was in charge of the RAF no LR Spit (except PR ones) were going to be in production, as he hang his hat (to Churchill, Arnold, etc) that a LR figher 'was impossible'. When the boss says no and his prestige is on the line, it is not going to happen. The Germans were just as stupid it has to be added.
Do you know the idiot was still arguing (in writng to Arnold) that it was 'impossible' as late as Sept '43, just as the P-51Bs were coming into play?
Very late model Spits (XVI for example) did finally have rear fuel tanks but with ridiculous operating limitations.

But a Mk V with a 250-300 mile combat range and a Mk VIII/IX with 500 miles was technically possible (and prototyped). Once they got a handle on the CoG issues (using bob weights and a revised elevator horn), the CoG problem only lasted until enough fuel (about 75%) in a rear tank was burned off in climb and iniital cruise. Exactly the same as a Mustang which was nearly as horrible until it did the prety much the same.

Because of its large wing tanks and lower drag a Mustang would always have a better range but you could trick up a Merlin 60 series Spit to about 70%-75% of that. Still very useful in (say) early/mid '43.

A longer range Mk V would have enabled daylight (and hence more accurate) raids on the French U Boat pens before they were hardened, arguably the single greatest strategic mistake of the whole British air war effort, heck a huge mistake full stop.
 

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