Messerschmitt 109 Improvements

Tante Ju said:

Right, just like on any other plane, including the Spitfire.

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That is simply not true. For the Spitfire you have to alter 8 of the frames and a few skins. All the rest of the structure, longerons etc remains the same.
For the Bf 109 you have to alter every single major component of the fuselage which are the skin plates and integral formers. The only things that would not need substantial alteration would be the stringers.
If you refuse to see the evidence presented by myself and others above then you will not be open to persuasion, and I give up.

The view out of a standard Spitfire is a lot better than the Bf 109, I've sat in both. The Spitfires had blown hoods which were adopted early on in the war. The thread was about improvements to the latter. I don't think it was any kind of issue for the Spitfire.

Cheers
Steve

FLYBOYJ said:

Also remember people in general were a lot shorter (and thinner) in the late 1930s than today.

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They were slightly shorter but I agree, a lot less likely to be overweight.
When I sat in a Bf 109 I was still a fit and relatively young man, certainly not overweight. A heavy build is I'm afraid a genetic advantage to a rugby player (a necessity playing where I did) though not to a WW2 pilot
Cheers
Steve

stona said:

That is simply not true. For the Spitfire you have to alter 8 of the frames and a few skins. All the rest of the structure, longerons etc remains the same.
For the Bf 109 you have to alter every single major component of the fuselage which are the skin plates and integral formers.

Cheers
Steve

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So you have to "redesign" 8 frames and 8 skins on the Spitfire. For the 109 lets assume you are right you have to alter every single major component of the fuselage which are the skin plates and integral formers.

Now please count the fuselage sections of the 109, between frame 2 and 9 thank you.



But you see the fact is - none of us know the exact amount of work involved, you just jump to the conclusion that intergral formers somehow make redesign incomparable harder than redesignning seperate formers, and that skin on the Spitfire is incomparably easier to redesign than skin on the 109. It just doesn't make any sense to me...

FLYBOYJ said:

Also remember people in general were a lot shorter (and thinner) in the late 1930s than today.

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True. Height is very much of a factor of nutrition at very young age. Now, in the 1920s when these young guys flying in that devastating war were anything but well fed... the Great War devasted economies and agriculture, and especially in Germany post-war entente blockade lead to famine...

Tante Ju said:

But you see the fact is - none of us know the exact amount of work involved, you just jump to the conclusion that intergral formers somehow make redesign incomparable harder than redesignning seperate formers, and that skin on the Spitfire is incomparably easier to redesign than skin on the 109. It just doesn't make any sense to me...

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I do know exactly how much work it takes to convert a low back to a standard Spitfire.......thank you.
You couldn't do it to a Bf 109 and the other way around would be just as difficult due to the engineering required on the Bf 109's structure. You can pop a few new frames and the altered skins (I can't remember how many, but relatively few, most remain unchanged) into a production line with virtually no disruption at all. How do I know? Because it was done.
That's me done too.
Cheers
Steve

Tante Ju said:

True. Height is very much of a factor of nutrition at very young age. Now, in the 1920s when these young guys flying in that devastating war were anything but well fed... the Great War devasted economies and agriculture, and especially in Germany post-war entente blockade lead to famine...

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and both the americans and the germans had recently come out of a depression economy....also to a factor to not being well fed.

They were slightly shorter but I agree, a lot less likely to be overweight

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I looked in the cockpit of a P-47 once, the Michelin Man would call it spacious in there! I remember reading somehere about how British pilots commented favourably about how big American fighter cockpits were.

We DO modifications to aircraft at the Planes of Fame and it just ins't that difficult. Someone is making mountains out of molehills.

You don't have redesign the entire rear fuselage ... you have to make the top curve shorter and redesign 5 - 6 bulkheads to have an abbreviated top curve, change the length of a few stingers (VERY simple), maybe a couple of longerons and maybe not, and resahpe the upper part of the skins.

The fin and rudder always could have been made a bit bigger and had trim added to the rudder.

From someone who does restorations and modifications, it isn't all that big a deal. The ONLY reason I would not do it today is becasue any Messerschmitt Bf 109 I work on should be a s stock as possible. Back in the war, it would have been a VERY different story.

They didn;t seem to have much trouble doing it to the P-051 Mustang, the Li-61 / Ki-100, the Spitfire, the P-47, or the P-40 (think P-40Q). Since EVERY ONE of tehse had the same thing done, how tough is it?

Answer, not very. The first trial example could be done by 3- 4 guys in 2 weeks or so with some plans (fuselage changes only ... someone else would have to make the canpoy and slide pieces.

A friend and I made a piece of trailing edge about 4 feet wide for a North American O-47 last weekend (port stub sing) from nothing but Aluminum sheets. We cut the 3 ribs, formed them, cut the top and bottom skins, made the stiffeners and a few braces, and drilled enough holes to hold them together in 8 hours on a Saturday. We took our time and will have this piece of trailing edge done in about a total of 3 Saturdays with 2 guys who are working at this for fun and not as a job. We shoot the bull while working and keep moving, but not at a breakneck pace ... it IS for fun, after all. The main issues are having the material, tools, and plans. We traced the original parts and went from there.

This just is NOT all that difficult as is being touted in here. Ask FlyboyJ ... he works on real planes, too and can do sheet metal.

When they punched a hole in the horizontal stab on Rare Bear at Reno on 2011, they had it pactched in 12 minutes. Applying the bondo, fethaering it in, wiping it with a tack rag, and painting it took longer.

Modifying an existing fuselage would take longer ... making a new one from scracth would be WAY faster and easier, and might or might not save time from the existing design.

It's sort of like turning a right hand Allison engine intoa left turn engine. It is a major change if you have an existing right-turning engine. But if you are building one up from parts, it is trivial to make a left-turning engine instead. There is a difference of 3 - 4 gears, a different wire harness for the spark plugs, and an opposite-turning starter. If you are assembling it from parts ... the difference is miniscule.

If you want to CHANGE it, you have to pull the engine, remove the accessory case, the nose case, change the starter, and change the wiring harness ... and, of course, the propeller. Time-consuming. But build it from scracth and the difference can be neasured in minutes ... the length of time to read the changed instructions for sequenced assembly.

@ GregP obviously you haven't understood how the rear fuselage of a 109 is constructed. Several times you stated that you have access to a Buchon at the museum so I suggest to have a look inside and you will see that your proposals will not work. Thanks Matthias Dorst who made a detailed documentation of the restoration of an original E-1 and the reconverting of a Buchon to G-2 standard at meiermotors with hundreds of photos on his website. I have posted the links earlier in this thread already so everybody who is interested can make his own opinion.
Sorry, I'm out now and will not post again in this thread.
cimmex

GregP said:

We DO modifications to aircraft at the Planes of Fame and it just ins't that difficult. Someone is making mountins out of molehills.

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GregP said:

This just is NOT all that difficult as is being touted in here. Ask FlyboyJ ... he works on real planes, too and can do sheet metal.

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Greg is right (thanks for the plug). Although original assembly considerations are taken into effect (example: "The fuselage construction of a Bf 109 is totally different. There are no particular formers. The formers are part of the relevant skin segment.")Many times it doesn't make any difference once the aircraft is assembled.

Folks, Greg and I (as well as a few other forum members) have worked on MANY aircraft, we are by far not god's gift to aircraft maintenance or aviation (as a matter of fact I consider every day I work a learning process and will never be too cocky or confident to continue to say "I know it all"). Unless you've driven some rivets, worked structural repairs or modifications, or restored aircraft to include war birds, please don't try to patronize us by your impressions taken from a book unless you've been there yourselves.

GregP said:

You don;t have redesign the entire rear fuselage ... you have to make the top curve shorter and redseign 5 + 6 buylkhead to have an abbreviated top curve, change the length of a few stingers (VERY simple), maybe a couple of longerons and maybe not, and resahpe the upper part of the skins.
This just is NOT all that difficult as is being touted in here.

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I can't believe what I'm reading

That is precisely what is involved to change the rear fuselage of a Spitfire or an aircraft constructed in a similar way. This is NOT what is involved to alter the rear fuselage of a Bf 109. I'm not going to go over it all again, but I have explained above.

Re-forming all the skin plates c/w integral formers for the Bf 109 is not a difficult engineering job, I don't believe it has ever been suggested that it could not be done. It is a difficult thing to do, mid production, in an aircraft series in the middle of a war. We are not talking metal bashing a prototype or museum example, we are talking re-tooling at least three major production facilities to produce an entirely new rear fuselage.

Cheers

Steve

stona said:

Re-forming all the skin plates c/w integral formers for the Bf 109 is not a difficult engineering job, I don't believe it has ever been suggested that it could not be done. It is a difficult thing to do, mid production, in an aircraft series in the middle of a war. We are not talking metal bashing a prototype or museum example, we are talking re-tooling at least three major production facilities to produce an entirely new rear fuselage.

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(while getting bombed around the clock)

BINGO!!!

Looking at the pressing machines I have seen, all it takes is a new etalon shape, really. Then the machine presses the sheets of aluminium to proper shape.

One factory could have been converted to construct the new fuselages. When all the wrinkles were worked out there, the next factory could have been converted and then finally the third factory.

Milosh said:

One factory could have been converted to construct the new fuselages. When all the wrinkles were worked out there, the next factory could have been converted and then finally the third factory.

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Easier said then done especially after the round the clock bombing campaign began. For the improvement in the aircraft IMO it wasn't worth disrupting the production line considering Germany's situation.

Then the machine presses the sheets of aluminium to proper shape.

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The skin sheets would have been rolled by hand in a roller then drilled to a pattern before fitting together on a jig, not necessarily machine pressed. Many of the components used to build these aircraft were made by hand using benders, folders etc then assembled by hand.

Redesigning an existing type, producing drawings for the new design, jigs etc and assembling a prototype using specialised engineers and staff is one thing, modifying an existing production line by retraining manufacturing staff, re-equipping jigs and facilities is another, not to mention the delay caused by the disruption of production to introduce the new changes. During wartime, with the stress of long working hours for the work force, the threat and sometimes reality of Allied air attacks that disrupted output and destroyed facilities, introducing changes was often extremely detrimental to the flow of production.

Wartime production staff were not 'aircraft engineers' as we know them, they were generally 'drones' (for want of a better expression) that followed processes and carried out single repetitive tasks. They were not necessarily highly skilled thinkers and had to be retrained in order to do tasks other than the ones they were employed to do. A rivetter working on final assembly would not necessarily have any experience on the folding line or forming line - it wasn't like today where as trainees and apprentices you go through different shops to learn different skills, wartime production staff were often women who had never worked before and people from all walks of life roped into doing single tasks on the line, and that's often all they did.

Just to set the record straight, I DO understand the Buchon fuselage, having been inside it. It would NOT be that tough, and major changes to aircraft were made all the time.

I find it difficult to belive that it would be that big a task for people who take raw Aliminum and make airplanes from it. That's why they have all those special tools.

FLYBOYJ said:

Easier said then done especially after the round the clock bombing campaign began. For the improvement in the aircraft IMO it wasn't worth disrupting the production line considering Germany's situation.

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There wasn't much bombing in 1942 when the Bf109G was first produced. The German situation was not that great at that time.

Automatic leading edge slats are used to maintain aileron authority into stall; most aircraft do without them by a combination of taper, washout, and local airfoil modification. Properly done, this does not increase cruise drag any more than retractable slats (and a lot less than fixed slots). Also note that no other fighters needed LE slats; this is definitely not because all the other designers were stupid clods and was absolutely certainly not because none of the other designers knew about them: take a look at a Dehavilland Tiger Moth.

Most other aircraft designers were able to get acceptable -- for various values of "acceptable" -- stall characteristics without Handley-Page-type (or, if you prefer, Lachmann; the idea was developed independently and roughly simultaneously) slats on their fighters.

Back to Bf109 improvements: a canopy with better vision out. When the Luftwaffe was doing all the bouncing on people, poor rearward vision wasn't a big concern. As the amount of bouncing by Allied air forces increased, being able to see behind became increasingly important. Also, the struts supporting the tail are likely to be significant sources of drag: they are on the suction side of the airfoil. Braces on aircraft like the Cessna 172 are on the pressure side of the airfoil, and disturb the flow much less. Getting rid of them would require a completely new horizontal tail (and maybe more; since the stabilizer is mounted on the fin, it's possible that the fin isn't stiff enough, and the braces are to compensate for that, too).

As an aside, I've read that the Bf109 had one of the highest zero-lift drag coefficients of any WW2 piston-engined monoplane fighter, with reported values as high as 0.029 (the Corsair was about 0.023,he Mustang was about 0.017; most other monoplane, piston fighters were between about 0.022 and 0.025). If that's the case (I have my doubts, but even if it's 10% high, it's still on the high side), the plane could use a good aerodynamic cleanup.

swampyankee said:

..... stall characteristics without Handley-Page-type (or, if you prefer, Lachmann; the idea was developed independently and roughly simultaneously)

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The two men became partners and life long friends. A much better approach than long patent suit battles.