TokyoMorose

as I understand it - not a single requirement but the conflict between having to fly two in a C17 and a 360 degree protection level beyond laughable.  The Requirements aren't strictly the problem - the problem is the engineering and technology development to meet them had to be done in a stupid timeframe and also had to be mature....  DoD clearly a victim of salesmanship over engineering.
 
  I have seen the docs but not sure if I have access to a copy.

I would bet money if I had it, that the requirements list was in the recent DoD tradition; being simply absurd and couldn't be met reasonably - and everything else is saving face for that. You don't end up with a sole offer on a program of that size, unless you are demanding something goofy. Nobody even bothered (sure, the Lynx technically couldn't be shipped in time - but failure to ship in time is something that reeks of the bosses not treating it as a plausible thing) to bid outside of GDLS, and if Breaking Defense is right, GDLS couldn't even actually meet the monstrous spec list.
 

Marder-like early experimental Warrior with Chobham. 750hp engine.

https://www.secretprojects.co.uk/threads/british-chobham-armour-micv.13467/

Vickers Mk.4 Valiant (1982):


 
 
 

So with FCS being too sci-fi, the army is repeating the mistake of the 84-ton GCV monster now in going maximum conventional. Do they not have a setting between 'pie in the sky tech dream' and '50 year old tech'?
 
Reminds me of the fact we have both the B-2 & B-52 in service...

In general, no - but a lot of the detailed ideas still remain extremely wonky, such as purposefully forgoing armor in total reliance for active protection. Even if you build an all-conquering APS, it'll still quickly deplete its loaded bank of shots. There's also a *lot* of as-yet unworkable electronics demanded, and they even considered stuff like exoskeletons. There was also a planning undercurrent behind all of the FCS designs that high-intensity peer conflict was a thing of the past. The general concepts they were working on are indeed workable now, but without your all-conquering APS and literally magic electronics & sensors they aren't nearly as viable - FCS was only viable on paper *because* of the all-conquering APS & absolute omnipresent networking & data fusion along with nearly omnipotent sensor systems. Even the latest sensors and networks are far below what FCS was aiming for.
 
(As an aside, FCS *was* laughably pie-in-the-sky technologically in the context of when it was approved! It'd be like trying to put the current top-line smartphones with everything they have into service in the mid 2000s, sure it's not seen as a big deal now but the Army were really "optimistic" with approving that program...)
 
 
There's some tested systems I seem to remember seeing that do alright against KE (I forget the names), although none fielded that I know of. The Quick Kill system proposed for FCS was extremely wonky, never fully worked right (although has some real impressive looking test footage!), and to this day still isn't fieldable. And then you get to the issue that the QC VLS cells were in packs of 4-8, and I've only ever seen one or two packs on the FCS vehicle renders. I've also never seen anything resembling a quick reload method for the QC, and so if worst case scenario you have only 4 of them loaded and the enemy takes 5 shots at you with an old T-12 Rapira... then what? Honestly not being able to rapidly reload is a total killer for an APS outside of Low Intensity patrols, and Quick Kill's design doesn't appear to be fast to load and certainly cannot be reloaded under armor.

So with FCS being too sci-fi, the army is repeating the mistake of the 84-ton GCV monster now in going maximum conventional. Do they not have a setting between 'pie in the sky tech dream' and '50 year old tech'?
 
Reminds me of the fact we have both the B-2 & B-52 in service...

So with FCS being too sci-fi, the army is repeating the mistake of the 84-ton GCV monster now in going maximum conventional. Do they not have a setting between 'pie in the sky tech dream' and '50 year old tech'?
 
Reminds me of the fact we have both the B-2 & B-52 in service...

Suffer. I mean enjoy.
 

I know I am late here, but the loon wouldn't happen to be Ernst Kniepkamp would it? I know with the half-tracks and Panzer III he was directly the guy responsible for those elements - and the Tiger I work at Henschel was also his pet project of the time.
 
And wait, I have Forcyk's book.... and yep it is Kneipkamp. Head of all tank projects at the Wehrmacht, and had been the chief army engineer even before the Nazi takeover when it was the "Military Automotive Department". Even the tiny Kettenkrad has the interleaved wheels, and yep the patent on that is "E. Kneipkamp".

I'm sure that all the SH regulars will know this backwards and forwards, so this is more for the benefit of newer people, or people who stumble in via google, or people who want a quick link they can throw out as an answer to anyone who asks the question.
 
So, what's with the goofy-ass road wheel design on German WWII AFVs?
 

A puzzled and terrified worker struggles to comprehend and assemble the suspension of a tiger I
 
You may have run into a variety of explanations for this running gear design; that it provided a smoother ride, that the design saved rubber, or possibly some other rubbish.  Like the myth that frontal drive sprockets provide more traction (seriously, how in the hell is that supposed to make any sense?), these wrong explanations of the merits of interleaved road wheels seem to rise from some quote taken out of context.
 
The interleaved road wheel running gear may have saved some rubber relative to an alternative design that was particularly wasteful of it.  But interleaved road wheels are not particularly economic in this respect because, and I realize this is a complicated concept to explain so I'll try my best, they have more wheels.  Interleaved road wheels do allow for large wheel diameters, and a larger diameter wheel will spread wear out over a larger circumference.  So interleaved road wheels might allow for the rubber on the wheels to last longer, although their construction would require more in the first place.
 
Interleaved road wheels would not improve ride quality either.  The ride quality of a tank is not a function of the size or number of wheels it possesses, but of how they are sprung.  So, it is possible that in certain competitive trials an interleaved road wheel design outperformed a design that lacked this feature.  I could readily believe, for instance, that the tiger (H) had a better ride quality on rough terrain than the tiger (P), or that the SDKFZ. 251 had a smoother ride than the M3.  However, this would be because the tiger (H) and SDKFZ. 251 have independently sprung road wheels on torsion bars while the tiger (P) and M3 do not.
 

 
Torsion bar layout of the tiger II
 

Volute spring suspension of the M3 half track
 
So, what do interleaved road wheels do?
 
They have two principal effects; one is a small benefit, and the other is an enormous detriment.
 
The small benefit of interleaved road wheels is that they spread the weight of the vehicle out more evenly on the track links:
 

 
The weight of a tank is not completely evenly spread out on the contact area of its tracks.  This is because tracks are not rigid.  If they were, they would be mainly ornamental and tanks' engines would just be for show.  More of the weight of a tank is concentrated under the parts of the track that the road wheels are sitting directly on top of.  Additionally, once a tank starts to sink into the soil a bit, larger road wheels work better than smaller ones because the larger ones have more contact area.  But you can only fit so many large diameter road wheels in the space of a tank's hull.
 

Dynamic!
 
 
So, the only way to have lots of road wheels and have big road wheels at the same time is to interleave them.  Simple as that.
 
If you would like an exhaustive look at the development of the semi-empirical MMP equation, read this.
 
The major, crippling downside to interleaved road wheels is that it makes changing the road wheels extremely time consuming.  
 

A pair of workers perform maintenance on a panther tank, and contemplate the futility of all human achievement
 
Lucas Friedli reprints in his book on big cat maintenance a report from a training unit complaining that replacing the inner road wheels of a tiger tank took ten hours.  That is completely outrageous, and was a contributor to the poor operational availability of the big cats.
 
For this reason, interleaved road wheels have rarely been used after World War Two; only on a few French prototypes and a Swedish APC:
 

PBV 302 variant with interleaved road wheels
 

Some bizarre French tank

Militari Al-Rusi UAZ technicals during "prophet Um Putini-2019" jihadxercise

 
 

Warrior hulls are too worn-out for upgrade so now the plan is to make entirely new ones.

Lol, so all this time you guys were seeing error notification as my signature, hahaha
 

I'm not sure about rainbows though Gotta dig deeper in the interwebz...

Looks back at the XM60... 

Personally, I blame the end of the Cold War - many 'western' governments more or less convinced themselves that they had no major threats likely and that existing equipment was 'sufficient'... so procurement has often been the first thing on the chopping block to save funds. The IDF & Israeli government crucially has a different view. The issues are pretty simple when you take into account the governments don't care.

Personally, I blame the end of the Cold War - many 'western' governments more or less convinced themselves that they had no major threats likely and that existing equipment was 'sufficient'... so procurement has often been the first thing on the chopping block to save funds. The IDF & Israeli government crucially has a different view. The issues are pretty simple when you take into account the governments don't care.

Personally, I blame the end of the Cold War - many 'western' governments more or less convinced themselves that they had no major threats likely and that existing equipment was 'sufficient'... so procurement has often been the first thing on the chopping block to save funds. The IDF & Israeli government crucially has a different view. The issues are pretty simple when you take into account the governments don't care.

The 2700hp MT-883 was the version developed for the EFV, this thing looks like the EFV but Korean. If they get it working, it'd be tempting to offer it to the USMC.

If they actually manage to get the 120mm Smoothbore, that'll be the most important advance in the whole Challenger family since the TOGS on the CR1 Mk 2...

The Brits way the Brits modeled things, any non-kinetic parts of ammo that are hit are likely to kaboom and take out the machine, and so ignoring the fact that the ammo is separated in an armored compartment, ignoring that in frontal hits that the rear of the turret is the hardest thing to penetrate in a tank (as you have to punch through the *entire* turret) the Brits said that hull-bottom stowage for live ammo segments has the least chance of being hit. This is technically true comparing the amount of frontal area in which it is theoretically possible to hit the ammo, but this is ignoring the facts that the hull is less armored & that they can't separate off the ammo storage behind bulkheads with their stowage arrangement.
 
Due to the ammo separation it's virtually impossible to K-kill an Abrams by hitting the ammo, while a Chally 2 was K-killed when a friendly HESH shell hit an open hatch... and the blast detonated the hull ammo stowage.
 
TL;DR - The Brits judged purely by amount of frontal area ammo is stowed in, irrespective of how armored or safe that area is. By that logic, T-72s have the safest ammo stowage of any modern tank...

I hate to barge into someone else's arguments, but several (almost all of his last post really) of DarkLabor's points don't really make sense.
 
 
British representatives still made exorbitant claims about Challenger after it's production run was effectively over despite the fact that we now know from leaked British documents their claims were bunk. People still believe what they want even after a project is over. And GIAT keeping FCS and Armor data "THE MOST protected data" is not unique to them either.
 
 
"Weak points" are not the same weaknesses between tanks. Even assuming that hit was through a weakpoint, it doesn't say much for the LeClerc's design that it managed to get hit in one. The Abrams has a comparatively fragile hatch, and yet in all the times they got hit in the mideast, I do not recall a hit managing to be landed clean on that hatch. No Chally 2 was knocked out to a hit to the drivers' optics despite the enormous chasm that was cut in the glacis armor for it. This suggests that the weakpoint on LeClerc is relatively large.
 
 
The best proof for the accuracy of the Swedish armor CAD models is the fact that neither the Germans or US (who also keep their exact data secret) complained about inaccuracies in modeling. There's also the fact that not a single outside test of LeClerc ever, has praised its armor in relation to late model Abrams or Leo 2s.
 
 
As to Greek trials - SH never claimed that the Radios were a crucial thing or a corner stone - just said they interfered. That they used the heavier tropical model does not stop them from reducing the weight of that relative to a normal tropical, which is what I am sure SH meant.
 
 
I already touched on this - KMW and GDLS do not openly discuss Abrams or Leopard 2 protection either. Literally nobody does, and SH is well aware of this. And yes, you have to get permission from the relevant export control authorities to get data on those vehicles as well. So the Swedes could jump through all the hoops with GLDS and KMW, but magically not with GIAT?
 
 
SH_MM is far from a "random retard", which is why I wrote this post. If your contacts are in the French army, of course they are going to say the LeClerc is the best. Everyone in the British army continued to say Challenger (both times!) was the best even after embarrassing performances that saw them lose time and again in trials. It is not in the interest of the French army to say their tank isn't the best, and it's also in their interest to tell everyone joining the armored force in France that their tank is the best. Troops in M1A1s in the late 80s were told that the vehicle could deal with every latest and greatest Soviet battlewagon without issue, and that they had armor capable of resisting whatever the Soviets could throw at them. We now know both of these to be categorically false, and that analysts at the time were aware of it in secret.
 
 
You just contradicted yourself. You said "it is the same as the other [...]" and that these drawings came from GIAT while the other is somehow "just a some stuff put together by the FMV". Which is it? Are the turret designs different, or was the FMV model correct?
 
 
That original statement you made was in fact very silly: "The engineers were not taking into account the other western MBTs when designing the Leclerc. They comply with the established specifications that took into account the latest warnings in the WarPact threats." When designing the Abrams, design specs were entirely based on hypothetical Soviet threats. Same with Leopard 2, same with Challenger. There was never a spec in Challenger that said: "we should make sure the armor is similar to Leopard 2, or better than Abrams".
 

For the inevitable conquest of the UK, they will have their drivers on the proper side!

For the inevitable conquest of the UK, they will have their drivers on the proper side!