Futures Past special: Was the Landkreuzer practical/ feasible/ sane???

 

As I write this, I am in the third week of a break from blogging. I decided that this was the time and place for something different that I had really been considering all along, a post on history and tech. This particular post will be on something I already covered in a Youtube rant, the Landkreuzer project, and whether giant land vehicles ever have and ever will be viable.

Now, the facts of the project mentioned will really be only a prologue here. At some point during World War 2, there was a request within Nazi Germany for designs for a tracked vehicle or vehicles weighing over 1000 tons, reportedly at the request of the Reich’s dictator. Everything from there has been unclear, particularly the extent to which any of it was taken seriously. At any rate, two major designs with nominal designations emerge in the lore. One is P1000, a tracked chassis mounting a battleship turret with 28cm guns. The other is the P1500, a self-propelled version of the actually built 80cm Gustav railway gun. And this was the extent of “super tank” development in real life.

But, of course, the idea has taken on a life of its own in science fiction. Even before the first tanks were fielded, H.G. Wells portrayed very large armored vehicles in “The Land Ironclads”. In the 1960s, the concept took on new life with Keith Laumer’s Bolo series, which portrayed the titular battleship-sized, AI-driven tanks with “hard SF” realism. Giant tanks and tank-like vehicles continued to appear in a range of subgenres and media, like The Legacy of the Aldenata, Warhammer 40K, and the Kenner Megaforce toy line. I personally threw in my hand with Aliens Vs. Exotroopers, featuring the 10,000-ton mobile lab Omega Aleph. Meanwhile, real life intermittently matched fiction with the development of giant tracked vehicle like NASA’s “crawler” and the Bagger 288 mining machine.

So, was all this ever “realistic”, either by the minimal definition that such vehicles can be built and function or in the stricter sense that they could have a useful purpose in war? On the first question, the answer must be a qualified yes. Vehicles like the Bagger 288 have exceeded 200 meters in length and 10,000 metric tons in weight. Given this precedent, there is no reason to doubt that human industry could build terrestrial military vehicles as large as naval craft if sufficient demand arose. On the second question, the real question becomes one of definitions. Of course, one can imagine a far future or alternate universe where battleship-sized craft launch ICBMs or Harrier jets or railgun slugs able to reach outer space. But does this meet the definition of a “tank”? This is where things get complicated, and this is where we can consider something that was actually built, the Maus tank.

The Maus, in brief, was an experimental tank developed and built from 1941 to 1944, principally by Ferdinand Porsche. It was the furthest development of Nazi Germany’s “superheavy” program. The final prototype weighed 188 metric tons, more than three times the size of a Tiger I and six times the size of a T34.  This made it the largest terrestrial military vehicle ever built, though it never saw combat. Both a 128mm anti-tank gun and a 15cm howitzer appear to have been considered for armament, though only the former is known to have been fitted on a working turret. Tests showed that it would run reliably, to the dismay of vocal opponents of the project in the Wehrmacht. However, its highest reported or plausible speed was 20 km per hour, and its weight posed severe problems for existing infrastructure. This was not, however, the reason that this was an obvious dead end I am annoyed even to have to talk about.

To see why the Maus was not workable as a tank, we must consider the problem of armament.  It is an observable fact that tank armament has always plateaued around 12cm, and the exceptions serve to show why this was the case. The KV-2 was a Soviet attempt to put a full-powered 152mm howitzer in a rotating turret on an existing heavy tank chassis, but this strained the base design so severely that it was reportedly prone to tipping over. On the Nazis’ side, the Sturmtiger/ Sturmorser mounted a mindboggling 38cm rocket launcher in a heavily modified Tiger hull, but it was universally classified as a self-propelled artillery piece rather than a tank. Finally, the much later Sheridan light tank mounted a short-barreled 152mm gun originally intended to launch a missile. Though this weapon was much lower-powered than that of the KV-2, it still produced severe recoil that could reportedly lift the lightly-built vehicle off the ground. The utility was further limited by low ammunition storage capacity. In light of this running problem, the bottom line for the Maus was that it had more than three times the weight of a more ordinary armored vehicle, but even with the 15cm gun, it could not offer more than twice the caliber or killing power of such a vehicle.

That is the practical problem, which might have been overcome. The deeper one is theoretical. The conceptual role of a tank is offensive and linear, which in turn means engaging an enemy at relatively close range. The noted 12cm limit for tank armament is very much the upper limit for what is necessary or useful in this role. Beyond that, you are transitioning to indirect fire, a jump as fundamental as that from a battleship to an aircraft carrier. There is conceptual and tactical room for a hybrid “howitzer tank” that can do both to some degree, as long as the fairly specific flaws of the KV-2 and Sheridan are dealt with. However, when the range of a vehicle’s primary weapon exceeds 16km, the best protection is to be at least as far from enemy forces of any size. If anything larger than a reconnaissance vehicle formation is close enough to engage with direct fire, let alone do so from behind, something has already gone wrong.

And that brings us to by far the most actually interesting superheavy vehicle of World War 2, the Karl. This was unarmored platform for a 60cm howitzer originally intended to demolish the Maginot Line, ultimately used at the siege of Sebastopol and the Polish uprising. At 11.4 meters long and 125 metric tons, this is the indisputable but unacknowledged record holder for the largest fully self-propelled vehicle ever used in open warfare. (And no, the claim that the Maus might have been used in an improvised last-ditch defense against the Soviets would not change that.) Its chief defect was that it was more movable than mobile, with a top speed of 10 kilometers per hour, and depended on rail to move any distance. The latter limitation specifically prevented its use in the particularly insane plan to demolish as much as possible of Paris before the German army withdrew from the city.

With this frame of reference, what becomes clear is that the  P1000 was a non-starter, even factoring in calculations that the vehicle as designed would have been far more than the nominal 1000 (metric???) ton weight. Putting a turret on a vehicle this heavily armed was simply redundant, while full armor would inevitably be too much and not enough: 10 or 20mm of plate would be enough to protect the crew from small arms fire, but even the armor of a Maus wouldn’t stop concentrated bombing. The P1500, on the other hand, was in the realm of the remotely sane. The Reich had already built not only the Gustav railway gun but more prosaically sized artillery like the famed and feared “Anzio Annie”, a 283mm railway gun actually of about the same caliber proposed for the P1000. With that frame of reference, we can at least figure out how big such a thing would really be.

That does bring us to some daunting considerations. The Gustav was over 47 meters long and weighed an astonishing 1,350 metric tons, obviously very close to the nominal 1500 tons proposed for the Landkreuzer equivalent. It also had 8 distinct sets of wheels. Anzio Annie, officially the Krupp K5, came in at 218 tons, still well over half again the weight of a Karl, carried between two sets of wheels. The Karl itself offers both a plausible means of construction and an “eyeball” range for size: Just strip down a few Karl platforms to no more than 100 tons each (for some reason, no precise figures for the platform minus gun are in circulation), and use it to replace at least one set of wheels on a railway gun. We can therefore extrapolate a weight of 400 to 500 tons for a self-propelled Anzio Annie, which is not a lot more than the mass for the two Maus tanks known to half been built. For the actual P1500, on the other hand, we are definitely looking at not less than 4 and possibly more than eight Karls worth of additional mass. That puts the minimum plausible weight somewhere between 1800 and 3000 (metric) tons, which is extreme but not entirely unfeasible.

That leaves the essential question, what could such a monstrosity actually do? In fact, we can at least deal with the obvious objections. If you’re already over 400 metric tons, there would be no reason not to throw in a few machine guns and light cannon for self-defense, which would be enough to deal with infantry and perhaps lone aircraft. It would still probably need to use the increasingly bombed-out rail infrastructure for most of its movement, but it wouldn’t be a sitting duck if there was a hole in the tracks. As for the usually cited problem of Allied bombing, it could be camouflaged (and for that matter partly dismantled) against discovery by routine raids and reconnaissance flights. If it came to that, it would be so much bigger than anything else that simply hiding in plain sight takes on a counterintuitive element of plausibility. After all, if your enemy’s common airmen don’t already know you have a vehicle the size of warehouse with the armament of a battleship, a weird platform with a giant tube on top isn’t going to look that much more interesting than a tank factory on the left or a munitions train on the right.

On the other hand, there are problems that don’t go away so easily. The existing weapons systems of the Third Reich were already running into the practical limits of their technology, evidenced conspicuously in the short barrel life of the Gustav guns. At the same time, there were technologies that were still unavailable, notably practical submunitions. (As I go into in the video version of this, the most significant experiment on that vein was, of all things, the United States’ surreal “X Ray” program to develop bat-deployed explosive devices.) Finally and most fundamentally, as seen with the Karl and the Sturmtiger, the Third Reich was simply running out of useful targets that weren’t already bombed to rubble. Given enough lead time, they could have turned a formations of Landkreuzers on the urban centers of Leningrad and Stalingrad, the concentrated armored forces at Kursk, and even the landing craft at Normandy. But without a nuclear bomb they didn’t have or chemical weapons even the Austrian painter feared to use, they probably weren’t going to do more damage than they could have with the same tonnage of Stukas, Panther tanks and V2s.

So, what of the future of the super-heavy military vehicle? The self-evident reality is that, for as many times as the tank has been proclaimed “dead”, there is still nothing better for what tanks are actually meant to do. Indeed, even tasks well outside a tank’s role, from carrying troops to launching ICBMs, have proven feasible for vehicles not greatly different in size and configuration. To get to a vehicle ten or more times the size of a tank, we would have to envision either a new mode of combat, an exceptional new threat, or both. Short of slugging it out with aliens in low orbit, any mission parameters we could envision would probably lead to a vehicle very different from what we would call a tank. Again, the tactical and conceptual leaps could be as great as that from a battleship to an aircraft carrier (maybe literally with VTOL aircraft and now drones in the equation), and we are free to admit we may not know what’s on the other side until we get there. The responsibility of the futurist is to think outside the box, and we are definitely due for something more than a battleship on tracks. Dream big, and reach for the sky… Just watch out for whatever is coming back down.