Military History | How To Make War | Wars Around the World Rules of Use How to Behave on an Internet Forum
Fighters, Bombers and Recon Discussion Board
   Return to Topic Page
Subject: How to fix the design defects of the Spitfire airplane of WW-II.
Shooter    5/26/2005 5:12:16 PM
Given 20-20 hind sight, It is easy to see where R.M. went wrong with the Spitfire! The following list of items is my idea of how they should have done it, IF THEY HAD READ ANY OF THE COMMON TEXTS instead of designing a newer SPAD for the last war! 1. Start with the late Seafire or even better the Martin Baker MB-5! they have contra props and wide track gear. The MB-5 also has a much higher LOS out of the pit forward. This is also one of the Spits larger problems. 2. Change the shape/planform of the wing and eppinage from eliptical to trapiziodal. The eliptical surfaces caused the construction time and cost of the Spitfire to be more than double that of the Mustang and almost as much as the P-38. 3. Reduce the wing cord and thus area by 35-40%! This reduction in surface aria will increase the cruising speed substantialy! This is probably the single biggest defect in the design. The change in aspect ratio will also help fuel ecconomy! 4. To compensate for the increased landing and take off speeds install triple slotted fowler flaps with a long hinge extension. This gives a huge increase in wing area and changes the camber for supirior "DOG FIGHT" ability, should you ever need it! ( because the pilot really screwed up!) At full extension and deflection, they would reduce the landing speed by 11~13MPH? (Slip Stick calcs!) 5. Remove the wing mounted radiators and install a body duct like the P-51 or MB-5! This one change would add ~35MPH to the plane? 6. use the single stage griphon engine and install a "Turbo-charger" like the P-38 and Most American Bombers had. This would increase power and save weight, both significant contributers to performance. 7. Remove the guns from the wings! This would lower the polar moment of rotation and give the plane snappier rates of roll! It also makes room for "wet wings" with much more fuel. A chronic Spit problem. It also fixes the Spit's gunnery problem of designed in dispersion! 8. Install the Gun(s) in the nose! Either fireing threw the prop boss/hub or on either side 180 degrees either side of the prop CL. This fixes the afore mentioned dispersion problem. One bigger gun between the cilinder banks or upto four 20MMs beside the engine or both, depending on what your mission needs were! 9. Make a new gun based on the American 28MM or 1.1" Naval AA ammo! This shell was particuarly destructive, had a very high MV and BC and was all ready in service. A re-engineered copy of the existing gun to reduce weight and increase RoF is a faily simple task. Pay the Americans for it if British spring technology is not up to the task! it also frees up much needed production capasity for other things. 10. Design a new drawn steel "Mine" shell for the above gun! Spend the money to load it with RDX instead of the TNT used for the first 4/5s of the war. 11. Pay North American or Lockheed to design it for you, since the Supermarine staff was to tied up fixing the origional spitfire design to get it done any time soon. Did I miss anything?
 
Quote    Reply

Show Only Poster Name and Title     Newest to Oldest
Aussiegunnerreturns    RE:Larry - The point   7/5/2006 4:40:48 AM
”My real problem is this: The Spitfire was an excellent piece of engineering that met the requirements for which it was designed very well indeed. But it was still a piece of engineering, and the engineering decisions in the design contained weaknesses as well as strengths. This is true of all engineering decisions. You fellows have even agreed to that, as a theory. But whenever a resulting weakness is pointed out, then come the howls of protest at the idea that the Spitfire is less than supreme at ANYTHING (except manybe range, and that doesn't really count because the Spitfire didn't need it, so obviously it wasn't needed at all).” Now hang on a moment. Go back to the initial post on this thread and re-read it. It clearly argues that the initial design of the spit was deficient and that it should basically have been re-built by North American. It doesn’t talk at all about temporary weaknesses compared to evolving German types that had to be corrected as the war progressed. It say’s that the original design was basically a load of crap. That is the side of this argument that you have (quite enthusiastically at times… remember when you were arguing that Allison powered P-40’s would have been better BOB warriors than Spits?) waded in on, so if you are getting howl’s of protest then there is your reason. That said, I agree that engineering decisions contained strengths and weaknesses. However, the Spit didn’t have many permanent engineering weaknesses that couldn’t be solved as new technology and experience became available. That initial design kept it highly competitive (not supreme, just competitive) with all contemporary piston engine fighters throughout the war. The fact that it could do that when it came into service so far ahead of everything that remained at the leading edge in ‘45, makes it a particularly inspired piece of engineering. Remember that three years is a long time when you consider how much a world war accelerates development. As for its shorter range than the American types, I don’t call that an engineering deficiency any more than I would call the F-16 deficient for having a shorter range than the F-15. The Spitfire and the F-16 were designed for specific missions that didn’t require an incredibly long range. For the Spit those missions involved interception and air superiority over the battlefield and it continued to do those (still important) missions well throughout the war. Eventually missions came along that it wasn’t suited for and Mustangs were the only type that could do those missions properly. So what? Airforce’s use mixes of types to address different needs now-days as well. The fact that a new type had to be introduced to do a different mission from the ones that the Spit was designed for, because of a change in strategic bombing doctrine, doesn’t reflect on the Spitfire at all. (except manybe range, and that doesn't really count because the Spitfire didn't need it, so obviously it wasn't needed at all)." "I did not say that the MkIX didn't return the advantage to the RAF over the FWs and '109s. My point is that the difference in roll rate was a serious tactical problem that had to be adressed." Actural combat experience as well as mock combats showed that the Spitfire's low roll rate was a serious drawback. Against a MkIX, it was one of very few advantages a FW-190A still had to exploit. The wing clipping at least partially redressed this, but (as with all engineering decisions) it came with a price. The clipped wing versions had longer take off run, higher stall speed and, of course, gave up some of its tight turn advantage and alititude performance. Now, what part of that statement do you want to debate??
 
Quote    Reply

Aussiegunnerreturns    RE:Larry - The point - addit   7/5/2006 4:43:41 AM
please excuse the fragments that I left at the bottom of my last post. They were meant to be discarded.
 
Quote    Reply

AussieEngineer    RE:Summary & Roll Rates - Additions   7/5/2006 4:47:27 AM
"To AE. Where can I find the report you referrence??? The context of the comment was mock combat at varying altitudes over England between RAF Spitfire Vs and IXs and 56th FG P47Cs in early 1943, shortly after the arrival of the Thunderbolts. The RAF report for AVIATION HISTORY which I quoted earlier had no context beyond being a comparison of a Spitfire VB and a FW-190A-3. The reversal manuever was described as having been tested repeatedly, without referrence to altitude or speed of the a/c involved with the consistant result: "the pilot of the Spitfire experienced great difficulty following the maneuver ..."" http://naca.larc.nasa.gov/reports/1936/naca-tn-550/ It is nice to about units and what not, but that wasn't what I was talking about. Context that makes a difference, as in airspeed, altitude, engine settings whether and so on.
 
Quote    Reply

AussieEngineer    RE:Larry - The point   7/5/2006 5:11:14 AM
"One other thing, the P51 DIDN'T dogfight Germans in the Spitfire's style. It couldn't. Unless it was VERY light on fuel, a Mustang couldn't match horizontal turns with a '109 or '190, and if he was that light, he had no business doing anything except bugging out for home. Mustang pilots used the same method as the Thunderbolt pilots for negating a tight turn: the yo-yo. Zoom upwards and spiral down inside the turn for the shot. ACtually, the Lightning could do tighter horizontal turns than the Mustang." Yo-yo's are dogfight maneuvers, there is no disengagement. I think it's is starting to become pointless talking about "close in fighting", "boom and zoom", "open style combat" etc. In my view it is either a continuous engagement or hit and run. Any aircraft that won't break apart in a dive can usually accomplish hit and run attacks with a reasonable expectation of success. What is more difficult is to successfully continue an engagement past the initial merge. Whether that is done through maneuvers in the verticle or horizontal or a combination of both is beside the point. The important thing is that is where the decisive engagement occurs. That is what you described occuring in the Phillipines.
 
Quote    Reply

MustangFlyer    RE: More Carbs   7/5/2006 5:14:16 AM
Yep and the RAE restrictor was good enough for most dive entries but not necessarily other or more prolonged manoeuvers, which is why it was replaced by the SU anti-G carb (March 42 onwards), then the (better) Bendix Stromberg carb (Merlin 66/70) and finally SU single point fuel injection. Another good old British 'bodge', that worked quite well until a more final solution could be created.
 
Quote    Reply

MustangFlyer    RE:Summary & Roll Rates - Additions - AE   7/5/2006 5:41:50 AM
Good find AE. Just some more details for those who read these posts and won't look at the original document: NACA Technical Note 550. Maximum Forces Measured as exerted by a pilot: Aileron: 90lbs (left to right movements on joystick) Elevator: 200 lbs (Pull/push movements on joystick) Rudder: 450lbs (legs on rudder pedals) Average Forces exerted by pilots: Aileron: 35lbs Elevator: 95lbs Rudder: 400lbs Which makes the 50lbs used for the tests on ailerons seem quite reasonable, especially if you take into account a pilot in combat may have to keep it up for 15 or minutes, plus the debilitating effects of heavy G forces and sucking on oxygen at high altitude. Some great stuff in these old NACA files.
 
Quote    Reply

MustangFlyer    RE:Larry - The point   7/5/2006 5:54:40 AM
Yes I agree (again). The first job of a fighter is to kill other fighters. Unless they are really dopy and/or have very inferior eqipment then descisive engagements at squadron level mean contineous engagement. Apart from "hunt and peck' (my term) or 'shoot and scoot' (another of my terms) then anything else is a dogfight, or more properly a contineous engagement in 3 dimensions until win/loss, disengagement through fuel/ammo shortage or poor tactical situation (or fear, 'heck my trousers are going brown, time to get out of here'). Another thing to remember that, unlike computer games, these were squadron/wing engagements. These were considerable numbers of planes engaging in combat. About the minimum level in WW2 was a flight (4). A pilot on their own (even with their wingman) got out of enemy space as fast as they could, unless they could rejoin their teammates quickly. Which makes the photo recon guys (all types) and the Intruders in Mossies so amazing (or daft).
 
Quote    Reply

MustangFlyer    Hey were coming up to the 1200.   7/5/2006 5:57:32 AM
I got the 1000, someone else (DB?) got the 1100. Who wants the 1200. Go for it Larry, AE or AG.
 
Quote    Reply

Aussiegunnerreturns    Hit 'n run n' shoot n' scoot...   7/5/2006 8:35:25 AM
... swing your lady round and round, clap your hands and hear the sound...." All these descriptives are starting to make me feel like I'm in Texas line dancing class. Yeeeeeehaaaaaa!!! ;-)
 
Quote    Reply

larryjcr    RE:Larry - The point   7/5/2006 1:18:13 PM
Responding in more or less order: To AGR: The initial post was by Shooter, not me. I contend (as I posted) that the Spitfire was an excellent solution to the preceived need as of '37, but that some of the design decisions proved to have serious drawbacks -- some of which could be dealt with, and some of which plagued the a/c throughout its career. In his effort of minimize weight and wing loading, Mitchell went with the single spar wing. The telescoping spar, and very complex internal structure gave very great structural strength at minimum weight, but made trying to stow fuel, weapons and ammo in the wing an ongoing problem. Even when the wing was re-designed to allow the installation of cannon, there wasn't room enough to 'toe' them inwards to give as close a harmonization point as most of the pilots would have preferred. And the lack of ability to stow more than a small amount of fuel in the wings was the road block to solving the a/c's greatest strategic fault -- its lack of adequate range. Another problem that stemmed from the same source was the narrow, comparatively fragile landing gear. This problem was most obvious in the Seafire, where the result was the a/c's very high operational loss rate. Lack of range in WW2 is not comperable to lack of range in modern a/c that can be refuelled in flight. In WW2 it put a major limitation on both operations and deployment. The inability of Fighter Command to take effective control of the air over coastal Europe during the period '41-'43, when they had an overwhelming numberical advantage was due to the inability to pursue the Luftwaffe far enough inland to force a decisive level of attrition.
 
Quote    Reply



 Latest
 News
 
 Most
 Read
 
 Most
 Commented
 Hot
 Topics