In that case, what is needed? Was the M113 the best idea and we just buy new ones? ;)

https://www.fnss.com.tr/en/products/m113-fov-capability-sustainment-program/m113-fov-variants

graylion said:

In that case, what is needed? Was the M113 the best idea and we just buy new ones? ;)

Its really a problem. The answer depends on what you want, need and most important can afford.

The M113 certainly has been a good idea at the right time. Never the less I like the Pbv 302 more.
Never the less the M113 is really outdated nowadays. If its brough up to modern standards it looses most of its advantages without really getting new ones to compensate. A M2/M3 based APC has long been overdue. Just like the Germany army should have followed trough with Marder based APCs. In general it seems a smart idea to use the chassis or at least significant parts of the IFV in service as base for a APV and equipment carrier. Its a tricky balance but its possible to save money by having parts comonality and limiting the number of different spares and wear parts.
The problem is currently there are few alternatives using a tracked drivetrain. The focus on cost reduction lead to modern APCs being wheeled in most cases. Furthermore several of the APC versions of IFV that did show up in the last decades are of the rolling bunker type intended for COIN and LIC in limited numbers deployment and low production numbers. Resulting in vehicles that are to expensive for general purpose use and large production numbers.

Maybe the tracked Boxer is a good idea? But i don't know enough about the tracked Boxer to really make judgement that has any foundation. The Boxer is also heavily focussed on protection though. Its large, heavy and expensive.
The articulated ATVs are not bad. Not at all. They are great vehicles but just not good for general purpose use. Maybe a more flexible, general purpose version could be made. Using more traditional metal tracks and dropping the amphibious capability.

schnuersi said:

Using more traditional metal tracks and dropping the amphibious capability.

Why metal tracks? I thought just for sheer crew comfort rubber tracks were the way to go - espcially on roads. Also track longevity?

YES on amphibiousness.

graylion said:

Why metal tracks? I thought just for sheer crew comfort rubber tracks were the way to go - espcially on roads. Also track longevity?

No.
Its not that simple. Rubber band tracks have advantages like dampening vibrations and noise but they also have disadvantages like massive wear especially on hard surface. They are also quite susceptible to certain ways of be strained. A rubber track can bend and deform orthogonal to the running direction. Which is really problematic on hard and uneven grounds.
There are good reasons why usually metal tracks with rubber pads or a rubber coating is used. The pads are easily replaceable. While a modern track for an MBT is good for ~5000 km the rubber pads are not. Not nearly. Dependent on how and where the vehicle is used the rubber pads are gone after 500 km.

While things like noise pollution and crew comfort are nice they are not a primary concern.

Look at the very wide rubber tracks in the picture. They also have significant ridges to get better traction on very soft soil. You can allmost hear the track scream: "please don't use me on concrete and if you do have some mercy and don't turn".
The black marks on the concrete is rubber worn off from the tracks.

This is where such tracks belong:
 

i.ytimg.com

schnuersi said:

While things like noise pollution and crew comfort are nice they are not a primary concern

Well, crew comfort may be a thing if they need a break after a few 100 km. But I see your point. 

schnuersi said:

Maybe the tracked Boxer is a good idea? But i don't know enough about the tracked Boxer to really make judgement that has any foundation. The Boxer is also heavily focussed on protection though. Its large, heavy and expensive. The articulated ATVs are not bad. Not at all.

Do the articulated one soffer any advantages over a regular box on-road? And what would be cheaper? A tracked Piranha V?

graylion said...

Do the articulated one soffer any advantages over a regular box on-road? 

An articulated tracked vehicle can be longer relative to its width compared to a normal one-piece tracked vehicle. Longer single piece tracks restrict turning ability. While that's more the case off road, there would still be an effect on road. The articulated vehicle would be able to take long, slight, curves smoothly while the longer tracked vehicle would tend to stick-slip its way around the curve

graylion said:

Well, crew comfort may be a thing if they need a break after a few 100 km.

For tracked vehicles a typical distance for technical stops and breaks would be 50-60 km. Wheeled vehicles go longer distances without break but they run on rubber wheeles.

Crew comfort is mostly important in the matter of ergonomics. You don't want your crew to wear out and get tired quickly. With hearing protection noise is not so much of an issue and with proper seating the vibrations also don't matter that much.
Incedental modern mine and IED safe seating also protects against vibrations. Modern noice canceling headphones are very effective as well. So because of changes and advances in other fields these two factors are less of an issue nowadays even though the regulations got conciderable more restrictive.

graylion said:

Do the articulated one soffer any advantages over a regular box on-road? And what would be cheaper? A tracked Piranha V?

As mentioned the articulation does mitigate most drawbacks of long vehicles. Its also nothing really special. Trucks and busses use the same concept.

I have no idea what a tracked Boxer or a wheeled one costs. I also don't know what the price of one Piranha V is and what it would be for a tracked version. Allthough I don't really see the point in making a tracked Pirnaha V. The idea behind the tracked Boxer is to be able to use the allready existing mission modules from a tracked platform. Since the Pirnaha V doesn't have such self contained and easy to change modules where is the point?
As mentioned there currently are few COTS sollutions. The CV90 and Bradley based APCs might but I don't know their price.

RovingPedant said:

An articulated tracked vehicle can be longer relative to its width compared to a normal one-piece tracked vehicle. Longer single piece tracks restrict turning ability.

1.  That articulated vehicles are typically longer than a "normal one-piece tracked vehicle" is not an advantage.

2.  Turning ability of an articulated vehicle is more restricted than that of a "normal one-piece tracked vehicle".

For instance, the Bv206 requires almost 2.5x its length to turn around, but an M113 can literally turn on a dime.

YouTube

M113 F3-Neutral turn

This is the Norwegian NM200 F3 built on the M113 A2 hull. NM stands for Norwegian model and 200 the version. I have provided you with a technical explanation...