United States Military Vehicle General: Guns, G*vins, and Gas Turbines

[Renegade334]

If you're referring to the M256 vs XM291 comparison, it can be found here: 20184655MNBT989107254F026170I002.pdf | DocDroid

 

Speaking of Abrams variants -- once upon a time, a certain duo made of Asher H. Sharoni and Lawrence D. Bacon (yes -- the very same pair who cooked up the Abrams AGDS with the twin Oerlikons and ADATS missile launchers) doodled another paper tank: the Abrams L52 Howitzer Concept.

 

Spoiler

 

 

Obviously, this went nowhere as it was merely a what-if concept -- besides, the Army was already busy developing the ultimately ill-fated XM2001 Crusader. Anyway, this article was published in the Armor magazine, November-December 95 edition.
...

...
...While skimming through it, I was quite horrifyingly reminded that this was the same magazine where a certain...M113 Simp...I mean, Mike Sparks, also penned down his fever dreams (in Nov-Dec 95, it was an argument to make a HMMWV version of the recoilless rifle-slinging M38A1C...and, a few pages further, there was also a rebuttal, by a Ft Lewis captain, of Sparks' love for the M113, his opinion of how Bradleys should be used as well as his arbitrary use of the name "Gavin"). Now, if you'll excuse me, I need to find some Clorox for my eyes?

[Ramlaen]

 

[Renegade334]

o_-;;

[Ramlaen]

https://www.defense.gov/News/Contracts/Contract/Article/3406522/

 

"`AM General LLC, South Bend, Indiana, was awarded a $4,653,330,000 firm-fixed-price contract for Joint Light Tactical Vehicles, trailers, kits and services to support production. Bids were solicited via the internet with two received. Work locations and funding will be determined with each order, with an estimated completion date of Feb. 9, 2028. U.S. Army Contracting Command, Detroit Arsenal, Michigan, is the contracting activity (W56HZV-23-F-0294). `"

[Clan_Ghost_Bear]

https://www.army.mil/article/267177/ampv_transitions_ngcv_continues_future_focus

Quote

In June, the Army selected industry partners to build prototypes of the OMFV. 

Either typo or the downselect is finally happening this month.

[2805662]

On 6/2/2023 at 9:00 AM, Clan_Ghost_Bear said:

https://www.army.mil/article/267177/ampv_transitions_ngcv_continues_future_focus

Either typo or the downselect is finally happening this month.

Rumour has it that the three finalists are BAE, GDLS, & Rheinmetall USA. 

[Ramlaen]

https://www.defensedaily.com/textron-details-ripsaw-m3-bid-for-armys-rcv-expects-decision-on-awards-in-september/army/

 

"Textron Systems [TXT] has officially submitted a bid offering its Ripsaw M3 platform for the Army’s Robotic Combat Vehicle (RCV) competition, and said it expects a decision on awards for the program’s initial prototype phase in September."

[Ramlaen]

https://www.army.mil/article/266856/soldiers_test_next_generation_family_of_medium_size_army_vehicles

 

FMTV A2 testing

[img]https://i.imgur.com/IbVkksg.jpg[/i

Spoiler

 

[Ramlaen]

 

[Ramlaen]

[Ramlaen]

 

 

 

[Renegade334]

Apparently, this UA Bradley incurred a direct ATGM hit on the turret and caught fire; the soldiers on board were nevertheless able to evacuate and the driver managed to take the vehicle back behind cover to extinguish the flames. No wounds sustained except for one contusion.

 

EDIT: not an ATGM, but a 122mm Grad.

 

[Renegade334]

^--- Looks like it belongs in a Toho Godzilla movie where it gets vaporized after firing a few Estes rockets. And, yes, this was a Japanese project.

 

 

 

^--- Apparently, the Fort Moore Armor Curator (Mr. Rob Cogan), informed Ronkainen that "XM1302" was indeed the designation for the prototypes.

 

Spoiler

 

 

Hmmm, don't see this often (no cringey joke intended) ---V

[CimaGarahau]

I've found a very rare document, the Finite Element Analysis of the ATAS turret, also called ATAC System Demonstrator or Thumper, the gun used is the XM291 with the 140mm gun tube, the same gun is also used in the CATTB Finite Element Analysis, but in the CATTB's case they renamed the XM291 140mm gun to L.W. 120.

How do i know they're the same gun? the stresses due to firing load of the CATTB gun (L.W. 120) is (375,000 lb), while the ATAS gun which is called (ATAC 140) share a very similar number, 370,000 pounds. This also reinforce that the CATTB used the 140mm gun tube.

https://apps.dtic.mil/sti/pdfs/ADA275853.pdf

[Renegade334]

Thumper was originally meant to receive the 120mm-barreled XM291, but there is PM-TMA documentation (20181815MNBT989112214F167098I011.pdf, which I previously linked here in this thread and the ballistics board) that indicates that the Thumper also trialed the 140mm ammo variety, achieving precision equal to that of a M1A1, but with penetration values well capable of defeating a notional FST-3's frontal aspect (speculated to be ~1m thick, but who knows which model TACOM used). All that was needed was a barrel change.

Quote

"Penetration performance was demonstrated during FTMA Armor Testing. The 140mm XM964 APFSDS cartridge defeated all SNR targets representing FST III."

Static test firings for 120mm were done in a crewed Thumper, but the 140mm were done remotely, uncrewed. Dynamic 120mm test firings were also conducted, but no mention of the 140mm.

 

The ATAS ATD project was supposed to have two vehicles, ATD I and ATD II, but the pictures of we have of the final vehicles (93/94) show some differences:

- ATD I was supposed to be built on a M1A2, not a M1.
- ATD I was supposed to have a 120mm XM291 gun and no autoloader (ergo, no need for a modified turret).
...Speaking of which, does this mean this picture is actually of ATD I, which might have mutated into CATTB Phase I? (I believe most pictures we have of the CATTB duo are of the Phase II vehicle) ---V

^--- Short turret storage baskets point to a M1 turret. The "stain" on the right turret cheek could possibly indicate an externally-welded weight simulator.

And, yeah, that looks like a XM291 (the bore evacuator doesn't have sloping extremities like the M256's), though I have seen here and there claims that this is a picture of a M1 testbed with a 55-caliber M256E1. Barrel thickness seems (YMMV) consistent with 120mm.
Possible issues with my theory of this being ATD I/CATTB Phase I:

- no panoramic turret with laser designator on the space reserved for the future CITV, as planned for ATD I. Only a M240 mount for the loader's topside station.

- no sign of the CMRS (Continuous Muzzle Reference System) atop the mantlet.

- tarp around the gun muzzle, not allowing us to see the planned combination collimator/mirror mount.

 

I'm also not sure which year was this taken. If it was in the 1990s, odds are this shows ATD I/Phase I.

 

The ATAS ATD II, on the other hand, was the most radical of the ATAS vehicles, clearly providing the basis for CATTB Phase II...but there were once again differences between the (now publicly available) plans and the final prototype we saw:

- No panoramic turret on the reserved CITV space.

- Gunner sight doghouse still there instead of a second panoramic turret (think AbramsX's pair of PASEO turrets).

- Still an M1 hull, not a M1A2.

- Still no CMRS atop the mantlet.

^--- Note the retaining rings on the drive sprockets and the trapezoid, rearmost side skirt segment - indications that that this is an original M1, not a M1A1 or M1A2.
Though the presence of both parts could been mandated to prevent the roadwheel-concealing tassels from getting snagged by the sprockets' teeth.

 

That said, I don't see any reason to build such a large turret bustle for Phase II unless TACOM intended for it to house the exceptionally long 140mm ammunition rounds. If it was only supposed to get the normal 120mm ammo, the XM91 cassettes could simply have been shortened, allowing for the use of a simple M1A1/A2 turret.

 

Obviously, plans (and budget allocations) changed in the meantime.

[CimaGarahau]

Jane's and Soldat und Technik says it's the XM291 with the 120mm gun tube, Soldat un Technik says the photo is from 1988 and Jane's says it's from 1987.

Indeed, it looks very identical to the ATAS ATD I, even the bore evacuator looks similar compared to the ATAS ATD l drawing and way it's smaller than the CATTB's bore evacuator

 

 

 

[CimaGarahau]

I belive this photo of the ATAC System Demonstrator shows the 120mm gun tube.

 

 

While this one shows the 140mm gun tube, you can see how thicker it looks compared to the first one, it also seems to very similar to the gun tube that appears on the video below.

 

[Renegade334]

^--- That's the Thumper indeed.

And I stand corrected about the photo. I unfortunately don't own either book, but the cited years do place that M1 testbed smack dab within the same time period as the Thumper (1988)...which, incidentally, was built out of a M1A1 from Anniston Depot, rather than a M1.

 

The only possible photo we might have of CATTB Phase I, now that I think about it...might be this:

 

 

Why? Well, because it has the exhaust grille for the AGT-1500. The CATTB Phase II with the XAP-1000 AIPS should look like this:

 

Also, note the different track pads (the new track had single 25in-wide shoes instead of the two 9in-wide shoes side by side) on the P2. The plan was to double the service life to something like 5,000-6,000 miles.

The P1 used the telltale T156 tracks.

 

Unless of course they sent the CATTB P2 back to the factory for an AGT-1500 refit, which would involve cutting the back of the hull and removing the new compartment bulkhead/divider (XAP-1000 was smaller than AGT-1500, which freed up 3.5m³ of hull volume for non-ready [mechanically autoloading] ammo storage). I must nevertheless confess that I do not know if the XAP-1000 was supposed to be removable from the powerpack compartment the same way the AGT currently is (opening the grille doors and sliding the engine out with the help of a crane) or if it's more of a Leo2 engine replacement-type procedure with a crane-powered vertical travel.

 

Another possibility is that there were two different hulls and the engineers at Aberdeen simply swapped the turret around with the help of a crane.
 

[CimaGarahau]

I'm pretty sure the CATTB Phase l is the one using a normal M1 hull, while the Phase ll uses a completely new hull  for the AIPS and for the hull ammo storage, while also applying the modifications suggested on the CATTB Finite Element Stress Analysis, they also installed the IN-ARM Suspension on the CATTB Phase l and Phase ll.
It seems like the M1 hull only got used because they hadn't finished the CATTB Phase ll hull.

 

Some info about the tracks.

 

 

 

Requirements for the hydropneumatic suspension.

 

 

 

Cadillac cage suspension.

 

 

 

Teledyne suspension.

 

[CimaGarahau]

  RED = CATTB Phase ll                                                                 BLUE = CATTB Phase l

CATTB Phase l

 

 

 

Very rare CATTB Finite Element Stress Analysis document in color and higher quality.

https://www.docdroid.net/f6S4v1w/ada228389-pdf#page=10

[Ramlaen]

 

[Clan_Ghost_Bear]

https://www.defensenews.com/industry/techwatch/2023/06/26/heres-who-will-move-forward-in-the-bradley-replacement-competition/

Only 2 OMFV contracts on the prototype downselect- Team Lynx and GD.

[Ramlaen]

XM30 huh

[Ramlaen]

https://www.army.mil/article/267920

[Ramlaen]