Alternative History Armoured Fighting Vehicles Part 3

The problem is the pressurized steam, not the fuel. There's a good reason why in rail locomotives the cab is usually as far away from the pressurized bits as reasonable.
Steam tractors for hauling artillery were regularly used so no issue there, but you never want to have one somewhere it might get shot, the resulting steam explosion might do more harm than the shell that opened it up might have.
Firetube boilers kill when punctured, as there is a huge volume under pressure.
Watertube boilers, has enough to pressurize the valve gear, lines and cylinders and not much more.
That why flash boilers were the choice for most steam vehicles that weren't on rails. Faster time from cold to power out was the main reason, safety#2
 
Firetube boilers kill when punctured, as there is a huge volume under pressure.
Watertube boilers, has enough to pressurize the valve gear, lines and cylinders and not much more.
That why flash boilers were the choice for most steam vehicles that weren't on rails. Faster time from cold to power out was the main reason, safety#2
Very true, although I'm not aware of a watertube boiler in production small enough for a reasonable 1900 AFV. I likewise thought flash boilers were a later development and not available.
Could be wrong but I was assuming that locomotive/steam tractor firetube boilers were going to be the only ones available at the time.
 
I likewise thought flash boilers were a later development and not available.
Could be wrong but I was assuming that locomotive/steam tractor firetube boilers were going to be the only ones available at the time
Mid 1890s, what was chosen by Sentinel for their Steam Wagon in 1905
 
Oh, well there you go then, a viable steam powerplant.
I think it would still be rejected over IC propulsion, even 1900, on the grounds of the relative fail-safe of a combustion engine when taking damage compared to a steam boiler, but steam power is definitely a possibility. I suppose it depends on the needs/requirements/restrictions of the governing body responsible for development.
 
Oh, well there you go then, a viable steam powerplant.
I think it would still be rejected over IC propulsion, even 1900, on the grounds of the relative fail-safe of a combustion engine when taking damage compared to a steam boiler, but steam power is definitely a possibility. I suppose it depends on the needs/requirements/restrictions of the governing body responsible for development.
I feel it would have been a great replacement for Germans to get rid of Horses in both World Wars.
Every now and then I repost the savings in pounds of fuel for Steam vs Horses. IC is better, but Steam can use Coal or other Biomass, and need less fresh water than the Horses, and IC needs finer tolerances and more complex gearing
Perfect being the enemy of good enough, and all that.
Missed opportunity
 
I entirely agree making use of steam lorries would have been a significant boon to Germany in the First World War. Very much a matter of technology slipping through the cracks. That they failed to make sufficient use of motor transport in the 30s is kind of evidence of how half-baked Germany's warplans really were once Hitler's gambling with international relations finally needed to paid up.
 
Alternate fuel...

2022-01-11 19_31_15-Window.png
 
One thing I don't really get about the M7 Medium Tank program is why the drift to a medium was allowed in the first place, and other related things.

It should have been pretty obvious to Ordnance that if the tank was closing on medium weight category, then it would have to compete with the M4 Sherman and more importantly the T20-23 series, which were in development long before standardization and production of the M7 was ordered. The M7 was never going to compete with them from a firepower standpoint when the primary purpose of T2X was to integrate a 3" or 76mm gun, and only barely from a protection standpoint.

It is also surprising that, with so much emphasis on alternatives to the precious radial engines, Ordnance decides to specify the R975 engine and cancel the lower powered alternatives to cope with increasing weight, when they should be reducing weight to not require an engine already limited in numbers for Sherman production. Even when one advantage of the M7 program was that they could massively change the layout compared to the M3 Stuart which used a radial at the time, and have a low and light tank.
To say nothing of the fact that some components were designed for a much lighter vehicle.

Getting a M24-style vehicle out of the M7 was hardly impossible in early 42 when the tank was in development. The Twin Cadillac+Hydramatic powerplant was actually chosen for the T7E4 and was getting integrated in the Stuart. At the same time the M7 was getting developped and prototyped, Buick made the T49 GMC which posessed a similar style of powerplant (Twin Buick, torque converter and hydromech suspension), and was of similar size.
The M24 weighed 40,000 pounds, the M7 allegedly 54,000, the T49 was definitely under 40,000. However, while the T49 was slightly less armored than M24, the M7 had between .3 and 1 extra inches of armor everywhere compared to the M24, with many places .5" thicker. So a lot of weight could be shaved off. A fully welded prototype could have been made to remove the issue of weight control with castings.

Even if the M7 with Cadillac powertrain and M24-level armor was still a bit too heavy, one could always continue redesigning it with features that went into the M24 to bring the weight further down, to avoid starting completely from scratch and causing further delays. It's worth remembering that the T49 which was developped over a similar timeframe was also extensively redesigned into the T70 (M18 Hellcat). If the M7 had followed a similar development path like I explained in the sentence before, then one could at minimum expect a new light in production by late 1943 like the M18, instead of not being fielded until late 1944 like the Chaffee.


The whole ordeal really sounds like a lack of discipline at Ordnance honestly, but I've heard more horror stories about their constant dithering.

 
Last edited:
The whole ordeal really sounds like a lack of discipline at Ordnance honestly, but I've heard more horror stories about their constant dithering.
mission and feature creep.
The US didn't really know what they wanted their light tank to do.
So minor upgrades in gun size and prototypes, while still building M5 with two man turret with the near useless 37mm thru June, 1944
m7tank-6.jpg

Above photo was May 26, 1942 at APG
The reports at this time was noted 26 ton weight, but good performance, unlike tests the following year after a years worth of twiddling specs
Just build the T7E2 with the 57mm and R-975 engine as the M7 first ones are overweight(too much armor than specified) until
the Bettendorf Arsenal gets their Foundry act together. That will be the M7E1 or full M7A1, with option to change to 75mm once the lightweight M6 75mm can be developed from the aircraft B-25 attack plane
Is this perfect?
Hardly. But it will utilize the Bettendorf Tank Arsenal that otherwise built just a handful of tanks during the War
So while the BTA is building a fun sized M4 Sherman, any of the other plants building the M4 can changeover to building something of the T20 series
 
Norwegian Truge Update:

The cleats have finally made it onto the tracks - all 64 of them. The current batch of WIP should give you a good idea of what the finished Truge will look like although the model still needs a bit of cleaning up and the Colt M/29 machine gun added. This in itself is a little bit of an issue as the Norwegian Colt M/29 (itself a licenced copy of the Browning M1917) and re-chambered to take the Norwegian 7.92 x 61mm round was a jacketed, water-cooled affair which is not a good fit for a turret-mounted weapon. I strongly suspect that the Norwegians would have gone for the Colt MG38BT (a derivative of the 1928 series but with an air-cooled barrel and specifically designed for use in tanks - very much like the Browning 1919A2) converted to take the standard Norwegian round. A model of the M1919A2 would work perfectly but alas I don't have one state-side (loads of the little blighters back home!)

As always, a spray of undercoat will help bring everything together. 👍

In the meantime...

Early 8.jpg


Early 9.jpg


Early 10.jpg


Early 11.jpg
 
Last edited:
Inspired by Garrison's TL "The Münich Shuffle" where a better prepared Britain give the Germans a much harder fight during the invasion of France (but still results in the conquest of France) and this of course leads to many butterflies. Link below.
https://www.alternatehistory.com/forum/threads/munich-shuffle-1938-1942.518000/

Stuh 38(t)
pXV4k53.png

The loss of more panzers during Operation Yellow leads Hitler to be convinced that Germany need harder hitting tanks and self propelled assault guns, Hitler orders more StuG III's be made but the General staff fearing this would lead to a reduce numbers of the Pz.III their main battle tank at the time, suggest that the Pz.38 (t) be converted into an SPG similar to the StuG. and this leads to the StuH 38 (t) and this...

Jagdpanzer 38 (t)
9vgvmCS.png

So the Germans get two new variants of the Pz.38 (t) earlier in the war but both the Marder and the Hetzer get butterflied.
Romania's Mareșal tank destroyer will also be butterflied as they will receive StuH 38 (t)'s from Germany and will copy the design for themselves.*

I plan on doing a 75mm armed version but this new AFV will also be slightly different than the OTL Hetzer.

These designs are my idea and may not appear in the fore mentioned TL they were inspired by.
 
Last edited:
Norwegian Truge Update:

The cleats have finally made it onto the tracks - all 64 of them. The current batch of WIP should give you a good idea of what the finished Truge will look like although the model still needs a bit of cleaning up and the Colt M/29 machine gun added. This in itself is a little bit of an issue as the Norwegian Colt M/29 (itself a licenced copy of the Browning M1917) and re-chambered to take the Norwegian 7.92 x 61mm round was a jacketed, water-cooled affair which is not a good fit for a turret-mounted weapon. I strongly suspect that the Norwegians would have gone for the Colt MG38BT (a derivative of the 1928 series but with an air-cooled barrel and specifically designed for use in tanks - very much like the Browning 1919A2) converted to take the standard Norwegian round. A model of the M1919A2 would work perfectly but alas I don't have one state-side (loads of the little blighters back home!)

In the meantime...

View attachment 711083

View attachment 711084

View attachment 711085

View attachment 711087
Installing those tracks must've been fun. :biggrin:
 

Driftless

Donor
What wood might the cleats have been made from? The first thing that popped into my head on seeing the installed cleats was the "birkebeiner" (birch legs) skiers of historic Norwegian lore
 
What wood might the cleats have been made from? The first thing that popped into my head on seeing the installed cleats was the "birkebeiner" (birch legs) skiers of historic Norwegian lore

@deLanglade, who’s idea the Truge is, specified that the cleats were to be made from White Oak as is often used for such things in Canada and Norway.
 
Installing those tracks must've been fun. :biggrin:

Yup… 🤪 wibble! 🤪

The tracks on the kit are actually quite a lose fit and so there is still a lot of movement. When I am finally happy with everything, I will probably end up gluing them in place to give a bit more structural integrity to the model.
 
How large is the Truge model (dimensions)?

As I started on my 1/72 Me 109 kit last night and I'd forgotten how small that scale is to build.

At 14.5cm x 8.5cm (5.75” x 3.25” for those still working in old money) it is by no means huge. Having said that, I once built a 1/76 scale FT-17 which was truly tiny. At least the Truge’s wider track base and cleats make it quite a bit wider than the original FT-17.
 
Top