Bf 109 Landing Gear Questions

[D.B. Andrus]

OK, this is will to be a bit esoteric, but here goes anyway.

Landing Gear assembly(left) Bf 109F: Part Number 109.219

" " " " Bf109G: Part Number 109.260

" " " " Bf 109K Part Number 109.260 or 109.280

My questions are as follows:

1. What are the differences between the 3 above parts?

2. What are the angles of the axles of the above parts relative to the center line of the gear leg? E.g., 90 degrees, 100 degrees, etc..

3. Does 109K part number 109-280 require large upper wing bulges to fit the larger tire?

3. What is the diameter of the oleo in each of the above parts.

There is a good reason for these questions, I promise.

Thank you for your attention and patience.

Cheers,

D.B.

[D.B. Andrus]

1. What are the differences between the 3 above parts?

Partial answer:

From German Aircraft Landing Gear, A Detailed Study of German World War II Combat Aircraft, by Gunther Sengfelder, Schiffer Military/Aviation History, 1993:

P. 183:

"The landing gear of the Bf 109F was largely taken from that of the E.

A series of landing gear modifications were introduced in the course of Bf 109G production, primarily caused the the aircraft's steadily increasing takeoff weight."

PP. 183-84:

"The following appears in a modification directive for the G-1 landing gear handbook: The exchange of small for large brake wheels is only possible after carrying out Modification Directive Bf 109 No. 280, or on aircraft which have been modified during production (recognizable by the presence of bulges in wing skinning).

Beginning with the G-5, the larger main wheels were installed on the production line. The revised 660 x 190 main wheels designed for the K series were first introduced on the G-10."

There is no mention of a change in the axle/strut angle only that an increase in the size of the brake assembly (and larger tires on the G-5 and later variants) led to the need for the upper wing bulge.

2. What are the angles of the axles of the above parts relative to the center line of the gear leg? E.g., 90 degrees, 100 degrees, etc..

Partial answer.

From Messerschmitt Bf 109F,G & K Series - An Illustrated History, by Jochen Prien, Schiffer, 1993.

PP. 84-85

"Along with the enlargement of the main wheels came a change in the angle at which they were mounted. Instead of being almost parallel to the undercarriage leg, the wheel's axis now approached the vertical. Both changes made necessary the addition of shallow, roughly teardrop-shaped fairings on the upper wing surface above the wheel wells, necessary to accommodate the upper part of the main wheels, which now projected further from the undercarriage leg when retracted......... Wings with the provision for the larger main wheels could be - and often were....retrofitted to the G-2."

Is this information current, is there primary source material available?

Best Regards,

D.B.

[D.B. Andrus]

Further research regarding the brake assembly, oleo strut and tire/wheel sizes of the following variants using Ersatzteil-Listen (Parts Lists) - all numbers for left side landing gear:

Bf 109F, Ersatzteil-Liste, April, 1941.

Oleo Strut - 8-2787.05
Brake Assy. - 8-2121 A-3
Tire/Wheel Size - 650 x 150

Bf 109G, Ersatzteil-Liste, March, 1942.

Oleo Strut - 8-2787.11
Brake Assy. - 8-3607 A-3
Tire/wheel Size - 660 x 160

Bf 109G, Ersatzteil-Liste, January, 1944.

Oleo Strut - 8-2787.13
Brake Assy. - 8-3607 A-3
Tire/Wheel Size - 660 x 160

Bf 109K, Ersatzteil-Liste, July, 1944.

Oleo Strut - 8-2787.15
Brake Assy. - 8-2106 A-1
Tire/Wheel Size - 660 x 190

After reviewing the above Modification Directive and parts list data I've come to the conclusion the angle of the axle was not changed, but only lengthened to accommodate the change in brake assembly and tire/wheel width. I would love to be proved incorrect in this. If anyone has primary source material please post!

Best Regards,

D.B.

[harrison987]

Hi,

The G10/K axles were exactly the same as the standard G.

A steel shaft that was WIDER and LONGER was slipped "over top" to accommodate the larger bearing/wheel...and an extension locked into that.

Attached is the diagram.

I had an exact set made from these drawings to adapt my gear legs. I also had original relic finds that were dug up from the 109K Erla Dump.

Mike

[D.B. Andrus]

Thank you, Mike.

Cheers,

D.B.

[gaupe75]

There are more to the change in landing gear than just track width, toe, camber and caster is also in this equation. I believe I've seen discussions about this earlier, sorry no sources at the moment.

Regarding the oleo and landing gear on the G, this was dependant on the weight of the plane, if it was supposed to carry a drop tank, bombs and gondolas.

[harrison987]

Originally Posted by gaupe75

Regarding the oleo and landing gear on the G, this was dependant on the weight of the plane, if it was supposed to carry a drop tank, bombs and gondolas.

No, that is not correct.

I have had NUMEROUS gear legs throughout all the restorations I have done. some NOS...some from crashes. I can tell you 100% there was no difference in the gear legs between a standard G6 and one that had a drop tank or gondola installed.

They used the same leg, regardless.

Keep in mind that there were MANY gear legs changed out in the field...as well as drop tanks AND gondolas installed that were not done at factory. The ground crew wasn't carrying different type of gear legs for when they installed a drop tank or wing gondolas. They simply added the equipment and off they went.

Also...

Every Me109 was designed to take ALL equipment. All had the ZBK241 installed in the rear...all had the electrical equipment and mounts for the wing gondolas...all had the mounting points of the drop tank.

Not sure where you are getting your info from...but 100% there were no difference in the gear legs when it came to weight differences.

There was also no way to adjust "toe and camber". it was a fixed leg with a fixed angle.

Mike

[gaupe75]

Originally Posted by harrison987

No, that is not correct.

I have had NUMEROUS gear legs throughout all the restorations I have done. some NOS...some from crashes. I can tell you 100% there was no difference in the gear legs between a standard G6 and one that had a drop tank or gondola installed.

They used the same leg, regardless.

Keep in mind that there were MANY gear legs changed out in the field...as well as drop tanks AND gondolas installed that were not done at factory. The ground crew wasn't carrying different type of gear legs for when they installed a drop tank or wing gondolas. They simply added the equipment and off they went.

Also...

Every Me109 was designed to take ALL equipment. All had the ZBK241 installed in the rear...all had the electrical equipment and mounts for the wing gondolas...all had the mounting points of the drop tank.

Not sure where you are getting your info from...but 100% there were no difference in the gear legs when it came to weight differences.

There was also no way to adjust "toe and camber". it was a fixed leg with a fixed angle.

Mike

I'll see if I can find the reference to the different landing gears, I do think it sound strange to introduce all of this logistics.

I did not mean that it was possible to adjust toe and camber on the landing gears, but one of the reasons for the large bulges on the wings introduced on the G4 and the G10/K4, allowed for more negative camber and toe in, which would help the stability on ground.

[D.B. Andrus]

Originally Posted by gaupe75

I'll see if I can find the reference to the different landing gears, .....

I for one would greatly appreciate this information.

Best Regards,

D.B.

[Graham Boak]

Introducing these changes is not strange at all, but an entirely normal process given the long life of the aircraft and its continuous development with ever-increasing weight. They are driven by the need to cope with the increasing loads and changing wheel/tyre sizes. The same process can be found on the Spitfire, with a series of different modifications to the undercarriage design. No doubt on other aircraft as well. Yes, this can be tough on logistics.

It is indicative of the problems when introducing mass production to the aircraft industry during the war: it is simply not possible to build a long line of identical aircraft because of the continuous arrival of modifications as a result of experience with the type and varying operational needs. Hence the need for batch production sizes well below that which was normal in the car industry prewar, or perhaps lorries in wartime.