Tail surfaces - 109F versus 109E?

[pstrany]

Hi;

Different sources have claimed that the size of the vertical fin and/or rudder of the Messerschmitt 109 changed from the Emil to the Friedrich model. Was this the case? The most visible difference was the deletion of support struts of course, but various sources also claim a difference in size and also the location of the horizontal plane - but not all sources claim this, and some site only a different in fin or rudder area, so both.

I will say I've had a terrible time trying to locate accurate drawings of these parts. Every other book seems to have drawings, but no two match, and more importantly, I can't get them to line up with photos of the "real thing" either. If I had a Friedrich in the shed out back I could just go out and measure, but unfortunately Friedrich's are fairly few and far between......

Paul

Paul

[mmoustaf]

Originally Posted by pstrany

Hi;

Different sources have claimed that the size of the vertical fin and/or rudder of the Messerschmitt 109 changed from the Emil to the Friedrich model. Was this the case? The most visible difference was the deletion of support struts of course, but various sources also claim a difference in size and also the location of the horizontal plane - but not all sources claim this, and some site only a different in fin or rudder area, so both.

I will say I've had a terrible time trying to locate accurate drawings of these parts. Every other book seems to have drawings, but no two match, and more importantly, I can't get them to line up with photos of the "real thing" either. If I had a Friedrich in the shed out back I could just go out and measure, but unfortunately Friedrich's are fairly few and far between......

Paul

Paul

According to 8.109-32 109F Seitenleitwerk drawing rudder of 109F from vertical axis to it's right point should have been 595 mm long vs 653 of 109E on 8.109-20 109E seitenleitwerk drawing while vertical dimension still remains the same 1404 mm. Shape looks like different also.

fin distance was 940.3 mm on F vs 898 mm on E.

But the distanse from rumpfachse (fuselage axis) to the line of stabiliser remains also the same 690 mm

Also 109E rudder had 3 mounting points vs 2 on F/G/K models

[pstrany]

Very interesting. Thank you for that. Still trying to get the shape right, but this at least gives me overall dimensioning, which is incredibly helpful.

[George Hopp]

Well, if you are after shapes, here are two. The first is from the development and characteristics of the Me 109F by Mtt in Jan 41; and the second is from "Aerodynamic features of the Me.109F2 and comparison with ME.109E" by the RAF, undated. I would tend to favour the RAF one since they would normally work harder to get things right than would the builder.

[pstrany]

Wow! Thanks for this! Yeah, I find builders drawings, especially German, to be a lot less than accurate.

Paul

[mmoustaf]

Originally Posted by pstrany

Very interesting. Thank you for that. Still trying to get the shape right, but this at least gives me overall dimensioning, which is incredibly helpful.

Sent You examples of factory dwg lists mentioned above.

[Graham Boak]

Originally Posted by pstrany

Wow! Thanks for this! Yeah, I find builders drawings, especially German, to be a lot less than accurate.

Paul

I find this rather surprising. I've no specific knowledge of the German industry, but it is the manufacturer's drawings that go to make the jigs and tools to produce the part: if the part doesn't match it is rejected, for wouldn't do the job for which it was designed.

I can see two possible explanations.

One is that you are not referring to the maufacturing drawings, but to what in the UK are described as General Arrangement drawings (GAs). These are often based on early project assumptions, and only show the basic configuration. They act as the reference centre, from which other drawings show the major assemblies, and so on down (up?) the design tree to the smallest bracket. The drawings of these parts are indeed accurate.

I can confirm that GAs from British aircraft companies did not always reflect later changes made to the design. That's not what they were for.

The other is that the drawings belong to some earlier idea of what the part should be like, different from that finally accepted for production. I'm sure it is very difficult to determine the detailed history of the design of major aircraft parts, and to place every detailed drawing in its proper place.

[Crumpp]

I find this rather surprising. I've no specific knowledge of the German industry, but it is the manufacturer's drawings that go to make the jigs and tools to produce the part: if the part doesn't match it is rejected, for wouldn't do the job for which it was designed.

That is absolutely correct. The manufacturer’s plans being off translate to substantial increases in labor and capitol expenditure for the company. While they did not practice six sigma, they most certainly were concerned with profit and quality control. Time and labor must be spent fitting parts as well those parts greatly altering the aerodynamic characteristics of the design.

It does not make sense for a company to do this and remain profitable. Even in the Soviet system, gross deviation from design plans was a major cause for concern.

All the best,

Crumpp

[George Hopp]

Paul asked for a comparison of the rudders of the 109E and 109F, and this I tried to supply. Neither of these drawings was a dimensioned effort and each was created to simply give an idea of shape changes. And, in both reports I referenced, that is all that was intended.

[Crumpp]

That makes sense, George.