List of objects for WIP maps: 3rd party contributors welcomed

[_1SMV_Gitano]

Let's start with a simple object which would be usefule for MTO maps:

V-shaped fighter blast pen

My guess is that the picture was taken in Lybia around 1941. I have photographic evidence that this kind of shelter was used up to 1943 in Axis airfields like Kairouan and El Aouina (Tunis). In some cases they were reinforced by earth fill on the external side...

[Spudkopf]

So I take it the dimensions are: length and width to accommodate something like a bf109, M202, Spitfire, Hurricane, Tomahawk etc and the height judging by the photo is about the same as the aforementioned planes (excluding the prop).

Looks like there is a left and right half with access/protection in the rear where the two halves overlap so the left hand Half is longer than the right.

The wall thickness appears to be about that or little more than that of the engine of the 109 currently in the revetment and the walls have a very slight 2° to 4° taper.

Will play around and see what I can do.

Scale is 50% of actual is this correct?

Is it stone or is it just a hastily erected sandbag pen, it just that it seems a little irregular for sandbags?

[Spudkopf]

Apart from the image that you have already posted, I'm struggling finding any further reference to "any" sort of revetments used in the MTO by either the allies or the axis (except for Malta), most shots show planes from both sides being serviced out in the open at un-penned and far flung dispersal points.

By contrast there plenty images of revetments for both the allies and the axis in Europe, but these are generally well engineered structures at established airfields or airbases.

The pen pictured above was as you say shot in North Africa, which would seem somewhat of a luxury considering the fluidness of front lines in that area of conflict during that period (as it appears to be either a F or G sitting in that pen), with air operations having to move from field to field being a regular occurrence, some fixed locations like Tobruk were duly fortified by both sides however.

So if you can point me to any further reference material that would be great.

[Spudkopf]

Well based on the photo this is my best estimate as to the possible dimensions for the revetment, as you can see it's only suitable for fighters as a stuka barely fits.

[Sita]

good scheme) nice!)

[_1SMV_Gitano]

Very nice.

You are probably right about revetmens in the Western Desert (Lybia and Egypt). On the other hand, blast pens were common in Tunisia, Sicily, Sardinia and mainland Italy, as well as in Greece. All major Axis airfields had tens of shelters of different size, as shown by Allied recce and later by Engineering Command surveys.

For example, the Luftwaffe built at Kairouan more than 20 of the small fighter revetments showed above. These were built between December 1942 and January 1943 to accomodate Fw 190s of II/JG2 (source: "Fw 190 in North Africa" book).

Kairouan


Tunis El Aouina


The following two are screen captures of material from the well known www.wwii-photos-maps.com website

Ariana


Protville West


This last one is about different types of revetments at Castelvetrano airfield, Sicily. The two smaller ones were likely made of stone. But I have no idea about the big one.

[Pursuivant]

My guess is that they were built using whatever materials were at hand - compacted earth, sandbags, fieldstone, or anything else that wouldn't blow away.

It's not Axis, but the Wikipedia article on aircraft revetments has two good pictures of RAF blast pens on Malta. One is made from stone blocks, the other from old fuel cans filled with sand.

https://en.wikipedia.org/wiki/Revetm...45._CM3241.jpg

https://en.wikipedia.org/wiki/Revetm...45._CM3237.jpg


Anyhow, textures are up to the designer, and probably should be quite simple.

[Pursuivant]

Originally Posted by _1SMV_Gitano

You are probably right about revetments in the Western Desert (Lybia and Egypt).

That does seem to be the case, even for airfields like Tobruk. My guess is that the war there was so fluid, and building materials so scarce, that they got used for infantry and gun positions.

Where there was more time to plan and better supply lines, there were more fortifications.

Also, there were 4 major powers fighting in the area - UK/Commonwealth, Germany, Italy & France. All of them probably had different engineering designs and specifications, as well as whatever field-expedient fortifications local commanders dreamed up.

Looking at the photos you provided, I'm seeing 7 different blast pen designs:

V-shaped, C-shaped, S-shaped, N-shape, a "crab claw" extended C-shape (Ariana airfield), an "anchor" or "arrow"-shape (|->, Protville West) and truncated V-shaped (like you showed originally), as well as the ]-shape or E-shape that we've already got in the game.

For the V-shaped designs, some are closed at the base of the V, while others have a narrow "S"-shaped passage through the walls for ease of access and, perhaps, shelter. Still others have "double V" design (<<), which might be a wall within a wall, or might be a structure faced with stone or sandbags and filled with dirt.

For the C-shaped designs, some are clearly structures made using stone or sandbag facings and filled with dirt. They'd probably have flat or rounded tops, as opposed to the pyramidal, or truncated pyramidal cross section that a rammed earth revetment would have.

Originally Posted by _1SMV_Gitano

All major Axis airfields had tens of shelters of different size, as shown by Allied recce and later by Engineering Command surveys.

Are the Engineering Command Surveys available online?

Are there field fortification manuals available?

[_1SMV_Gitano]

Originally Posted by Pursuivant

That does seem to be the case, even for airfields like Tobruk. My guess is that the war there was so fluid, and building materials so scarce, that they got used for infantry and gun positions.

Where there was more time to plan and better supply lines, there were more fortifications.

That is my guess too. Apart that, the general policy of the Allied in the mid-to-late war years was to use widely dispersed hardstands rather than shelters. This was true for the all theaters. Just compare any early war airfield with the later ones. Malta was obviously an exception.

Originally Posted by Pursuivant

Also, there were 4 major powers fighting in the area - UK/Commonwealth, Germany, Italy & France. All of them probably had different engineering designs and specifications, as well as whatever field-expedient fortifications local commanders dreamed up.

That was probably true in the early war years. But from early 1943 onwards unification of commands and procedures was steadily introduced by the Allied forces. This applied also to airfield construction. On the other hand, by 1943 most of the development of airfields in the MTO was carried out by the Germans, while the Italian logistic machine was collapsing.

Originally Posted by Pursuivant

Looking at the photos you provided, I'm seeing 7 different blast pen designs:

V-shaped, C-shaped, S-shaped, N-shape, a "crab claw" extended C-shape (Ariana airfield), an "anchor" or "arrow"-shape (|->, Protville West) and truncated V-shaped (like you showed originally), as well as the ]-shape or E-shape that we've already got in the game.

For the V-shaped designs, some are closed at the base of the V, while others have a narrow "S"-shaped passage through the walls for ease of access and, perhaps, shelter. Still others have "double V" design (<<), which might be a wall within a wall, or might be a structure faced with stone or sandbags and filled with dirt.

For the C-shaped designs, some are clearly structures made using stone or sandbag facings and filled with dirt. They'd probably have flat or rounded tops, as opposed to the pyramidal, or truncated pyramidal cross section that a rammed earth revetment would have.

Having all possible variations would be too much. I would be happy to have the small and V and C types for fighters, the cutted hoctagon (similar size to n.2 in the scheme above) and a couple of single, linear walls to use as wildcars in the construction of blast pens...

Originally Posted by Pursuivant

Are the Engineering Command Surveys available online?

Are there field fortification manuals available?

Documents are not available freely. You can browse the title of each folder but then you have to purchase a copy of the microfilm, it's 30 US dollars each. For the MTO Engineering Command there are at least 11 rolls, plus those containing aerial recon reports. I managed to purchase four of them but at the moment I'm not in the position to get more. The quality of the material is not uniform, so it is not easy infer the evolution of a single airfield with time, and a lot of research and guess is needed. But for Tunisia and Sicily I hope to provide multiple time frames, like Solomons and NGNB maps.

[Spudkopf]

As far as I can work out a standard metric sandbag is 600mm x 300mm x 150mm (L x W X H), while and imperial sandbag is 2' x 1' x 6", so knowing this and using an alternating brick lattice style stacking of the sandbags then this could give a result something like this:



I guestimated 750mm for the wall thickness in my pen drawing, but this could just as easily be 600mm, but there is also an obvious taper that would not occur with this style of stacking!

Looking at the smallest pen (1) in the diagrams it looks like the internal dimensions are 48' x 37' , however I am unable to work out the wall thickness, other than it appears to be measured in inches and not feet and almost looks like 8" which is about 200mm !?!