US Army AAA in T2K

[Raellus]

Always a Need

Back in the day...

I'm just surprised that the US Army didn't see a need for a fast-moving*, mobile AAA platform during the last few years of the Cold War. At that time, the Soviets were spinning up their new Mi-28 Havok and Ka-50 Hokum attack helicopters, both of which posed a threat to US armor (especially when it was on the attack). This would have been the perfect excuse for the US Army to request a new SPAAG. Perhaps the expensive boondoggle of the Sgt. York program soured all involved on SPAAGs.

I think this was the rationale behind the M691 Diana SPAAG in the v1 US Army Vehicle Guide. I used to think it was silly, and probably prohibitively expensive given the pricey M1 chassis, but now I'm not so sure. It had to be speedy enough to keep up with Abrams on the run. I think my main gripe now is that it's armament of twin 20mm canon seems too light. If you're going to use an MBT chassis, load it up! I think 40mm or 30mm would have been a lot better (longer-legged and heavier hitting)- or 25mm at the minimum.

Today...

Drones are becoming a pervasive feature of the modern battlefield, and are already in use as improvised AT weapons (either in suicide attack mode or dropping bombs on AFVs' thinner top armor). In my mind, this brings back the need for SPAAGs. I imagine a Vulcan canon would make short work of most low-flying drones. However, once drone swarms start arriving over the battlefield...

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[Raellus]

US Air Defense Vehicles by James Langham

Just stumbled across this by accident while looking for a prototype AT jet marketed during the late '80s (I still haven't found it). IIRC, this doc was shared here on the forum before, but I can remember when or where.

https://thetwilightwar.weebly.com/uploads/1/2/0/7/12075290/us_air_defence_vehicles_02-01-12.pdf

The creator is James Langham, a member of this forum. I think he's consulting on Free League's v4 as well.

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[madmikechoi]

Back in the day...

I'm just surprised that the US Army didn't see a need for a fast-moving*, mobile AAA platform during the last few years of the Cold War. At that time, the Soviets were spinning up their new Mi-28 Havok and Ka-50 Hokum attack helicopters, both of which posed a threat to US armor (especially when it was on the attack). This would have been the perfect excuse for the US Army to request a new SPAAG. Perhaps the expensive boondoggle of the Sgt. York program soured all involved on SPAAGs.

There's only so much money Big Army can throw at any system and each dime was fought tooth and nail at the Pentagram. Succeed and the colonels
get stars and then cushy gigs w/ the various beltway bandits that masquerade as defense contractors. Fail... well they work for contractors so it's all good

If we decide that Big Army decided to get its head out of their proverbial ass and recite the ADA holy mantra of having a gun/missile mix and SHORAD is not the destruction but to preserve the assets of the brigades and battalions from enemy air attack. In which case even damaging enemy fixed wing and rotary platforms or making said individuals piss off for greener pastures is just as good as turning them into fireballs and greasy stains (virtual attrition is a thing but Congresspeople do not understand that)

Today...

Drones are becoming a pervasive feature of the modern battlefield, and are already in use as improvised AT weapons (either in suicide attack mode or dropping bombs on AFVs' thinner top armor). In my mind, this brings back the need for SPAAGs. I imagine a Vulcan canon would make short work of most low-flying drones. However, once drone swarms start arriving over the battlefield...

Keep in mind the sensors we have today did what folks wanted to do back in the 80s and 90s Air cooled Sure. Doppler tracking You can do it w/ raspberry pi kit. Integrated into a network and able to share data w/ multiple platforms no matter if it's in the air or it floats Yeah, we can do that sez Raytheon, Northrup Grumman, and Lockmart.

Even a cheap gun type system like the Blazer (in retrospect the mil designation would have been something M10xx but GDW didn't know that or thought Big Army would have gone back to cover the M700 series) fitted w/ those tiny dinner plate AESA radars would have given tracking coverage at least out to 10 plus klicks/5 nautical miles depending on terrain and weather. And something like the ADATS w/ a 3D AESA radar while overkill against certain UAVs may end up as a limited coverage against tactical ballistic missiles given software and rocket motor mods.

Mad Mikec

[Vespers War]

Back in the day...

I'm just surprised that the US Army didn't see a need for a fast-moving*, mobile AAA platform during the last few years of the Cold War. At that time, the Soviets were spinning up their new Mi-28 Havok and Ka-50 Hokum attack helicopters, both of which posed a threat to US armor (especially when it was on the attack). This would have been the perfect excuse for the US Army to request a new SPAAG. Perhaps the expensive boondoggle of the Sgt. York program soured all involved on SPAAGs.

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ADATS was supposed to lead to that. It was a dual-purpose SAM/ATGM with a top speed of Mach 3, a 10 kilometer range, and semi-active laser homing (jamming was more of an issue than dazzling when it started development). An 8-missile turret would be placed on top of a Bradley, along with a 25mm Bushmaster. There was also talk of developing an M1-derived Air Ground Defense System with a pair of six-cell ADATS launchers and twin 35mm Bushmasters working in teams of six to engage up to 20 targets simultaneously, per the July-August 1996 issue of Armor. The missiles never reached the required milestones for reliability, MTBF, or serviceability.

The M1 AGDS concept had been around earlier as the Thomson-CSF/LTV Liberty series of proposals for the LOS-Forward-Heavy AAA system, as described here:
Liberty - AMX-30 chassis, 6 Shahine (Crotale) missiles
Liberty I - M1 chassis, 2 12.7mm MGs, 6 Shahine or 12 VT-1 (Crotale NG) missiles
Liberty II - M1 chassis, 2 25mm Bushmaster, 12 VT-1 missiles
Martin Marietta and Oerlikon won the competition with ADATS, which then flopped even worse than the Sgt. York.

[swaghauler]

Pardon my typing, I haven't gotten home to get my poor ailing computer yet, so I'm typing this on my old S7 smartphone. The touchscreen keyboard leaves a lot to be desired.
I don't have it in the truck with me but there is a book printed by the Army every year that they give to Congress. It is a "wish list" of weapon systems they are seeking funding for. Skyhorse Publishing usually puts out the declassified versions. I have one from 2016 and the Army was seeking funding for two AAA systems to test.

The first was a self-contained module like the CROWS (common remotely operated weapon system) with a millimeter wave radar and an optical tracker paired to a GAU 19 50 Caliber gatling gun and TWO 4-round Stinger Missile modules. It had 2k rounds on the mount and was designed as a swarm drone defense system with a secondary ground attack capability. The unit would be mounted to either a Hummer or a JLTV with the crew firing the mount remotely from inside the uparmored vehicle. Unit weight was listed as around 2 metric tons fully armed with remote fire control station. This is only slightly heavier than a Navy MK38 25mm gun mount.

The other unit (fully experimental) caught my eye because it would fill the gap between the PATRIOT and SHORAD. The proposal was an M109 chasiss fitted with a tall turret containing an AESA radar, IR Tracker, IR optical sensor and Laser ranger/Designator. The weapon system consisted of either a 3 or 4 round box launcher trainable in elevation on either side of the turret for Rolling Airframe Missiles AND a center-mounted 57mm MK110 Cannon (with a pretty long barrel). The canon was equipped with a dual feeding mechanism on either side of the cannon containing 10 rounds in a vertically feed hopper and ejected its spent casings forward over the barrel and towards the right of the hull deck (to avoid the driver). 40 additional rounds would be stored in the turret bustle for 60 rounds on the mount. The listed Crew is driver, gunner, commander, and two loaders for the 57mm (one on either side of the cannon). I don't know if any more RAM Missiles were carried. The radar folded down for transport just like most modern SPAAGs can do. It looked about as tall as an M109A6 with an equally large turret and turret bustle (the back of the turret where ammo is stored). The drawing had access doors on the back of the turret (presumably to speed up reloading the ammo). Effective engagement range was touted as 10km with a 6km slant range for the cannon. The IR Optical tracking allows for NOE aircraft engagement and operations in a radar-denied environment. IDK if any actual prototypes are running around yet but the Marines new hybrid LAV turret's Stinger weapons mount looks suspiciously like the SHORAD mount's box launchers.

[Ursus Maior]

I think, the bigger picture is important here. SPAAG projects died with the Peace Dividend for obvious reasons. Germany was lucky to have one of the best systems in the world (if not the best, at least in the west) and kept the Gepard running until 2011. Combined with Roland on its Marder IFV chassis, that was a very solid protection level.

In an alternate history where the USSR remains a larger thread than Russia during the 1990s was, even in a T2K v. 4 variant, where a short Peace Dividend seems to have been the case, SPAAG systems would have probably been a thing for most NATO armies. So, the usual question is, what to buy. There is DIY and OTS. All do-it-yourself projects are costly and can fail (cf. the M247 Sergeant York), but gains to national knowledge and economy are a clear pro. OTS solutions were available back in the day with the Gepard an obvious solution and the Marksman system a less known one. Still, the US Armed Forces usually had problems buying these things from abroad, even from their allies, with Roland being a notable exception.

Solutions from within the USA were available though and either failed historically mostly because of the changing political climate (ADATS on M113 or Bradley) or were bought in only small numbers. The M6 linebacker and the M998 HMMWV Avenger as well as the M1097 Heavy HMMWV Avenger respectively were bought, but did not perform as well as other solutions, if I am correctly informed. M163 VADS always was only a stop-gap solution.

Buying Marksman could have been a solution, though. Buying British instead of German might have been politically easier, especially if one would have used older M48 or M60 Patton tanks as a chassis. The former was offered as a solution for Marksman by Marconi Electronic Systems from ca. 1994 onwards, the latter was never offered, but I do not see, why it could not have worked.

While keeping the M48 chassis alive for another 10-20 years might not seem like a good idea, Marksman would have been a cheap solution that could offer first tier results (in the mid-1990s). The M48 chassis is well suited for the job, thousands were available readily, since the M48 was becoming clearly obsolete as an MBT, even with all upgrades available (L7 105 mm gun, MOLF laser range finder, thermal sights, modular applique armor or even ERA and a new MTU power pack). As a SPAAG a new power pack and the Marksman turret would have been more than sufficient, though. In an alternate history, where the USSR remains a real, though diminished threat, it is likely that the Detroit Arsenal would have remained fully operational as a tank factory, allowing for a swift modification process during the 1990s.

[Raellus]

Thanks, Ursus. I don't recall reading about the Marksman system before. It looks pretty promising. Although ostensibly British, its multinational nature might make it less palatable to the Pentagon than a single-country source like Gepard.

Do you know if the M48 chassis (or M60) could have supported the Gepard turret I can see the Pentagon making a deal to produce said turret here in the states and fit it to an all-American MBT chassis. The resulting SPAAG wouldn't quite be able to keep up with the M1/M2 on the trot, but it would be better than no AAA system at the front line.

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[Vespers War]

Do you know if the M48 chassis (or M60) could have supported the Gepard turret I can see the Pentagon making a deal to produce said turret here in the states and fit it to an all-American MBT chassis. The resulting SPAAG wouldn't quite be able to keep up with the M1/M2 on the trot, but it would be better than no AAA system at the front line.

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An M48 with a slightly modified Gepard turret (different radar and computer) was Raytheon's proposal for the DIVAD competition that gave us the Sgt. York.

[Raellus]

An M48 with a slightly modified Gepard turret (different radar and computer) was Raytheon's proposal for the DIVAD competition that gave us the Sgt. York.

Interesting. Any idea why it was rejected (or why the Sgt. York got further along in the process)

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[shrike6]

An M48 with a slightly modified Gepard turret (different radar and computer) was Raytheon's proposal for the DIVAD competition that gave us the Sgt. York.

I had some articles I found on the DIVAD competition a while back. Ill see if I cant dig em up and post them.

[Ursus Maior]

May I say that I never actually understood the M247 Sergeant York I mean, the US was already well underway with the M1 Abrams and the M2 Bradley, two of the most modern and best pieces of hardware at the turn of the decade into the 80s. And then they devise something so ugly, patched together and insanely ad-hoc like the M247 and cannot even make it work

I mean, look at that thing: The chassis of the Gepard was not new, it's based on the Leopard 1, but the M247 is based on the M48 and the turret is so boxy that it looks like a WW2 tank missing a couple of rivets.

There were good contenders, Raytheon's Dutch Gepard turret could have been mated with an M48 chassis, General Dynamics mated the 35 mm Oerlion guns used by the Gepard with CIWS systems using what looks like a M48 chassis as well. And finally General Electric wanted to use the 30 mm GAU-8 Avenger. Probably an outlier solution, unless T-72s were known to grow wings.

[mpipes]

My understanding that a major contributing factor toward cancelling the M247 was the M48 hull. It was too slow. So any viable alternate solution needed a Abrams or Bradley hull.

The truth of the matter is that the US has not really put any priority on unit level AA. The Army seemingly has decided on primarily relying the USAF and Patriot SAM and I guess the Stinger MANPADS. Sooner or later, the US military is going to pay a hefty price by ignoring tactical, unit level air defense.

[Vespers War]

My understanding that a major contributing factor toward cancelling the M247 was the M48 hull. It was too slow. So any viable alternate solution needed a Abrams or Bradley hull.

The truth of the matter is that the US has not really put any priority on unit level AA. The Army seemingly has decided on primarily relying the USAF and Patriot SAM and I guess the Stinger MANPADS. Sooner or later, the US military is going to pay a hefty price by ignoring tactical, unit level air defense.

All of the DIVAD entrants were based on the M48 hull (it was a proposal requirement), so that might have been a problem regardless of who won. I say might because I'm not sure the other entrants added as much weight as the M247 did (17 tons heavier than a normal M48). The Gepard's turret only adds 5 tonnes to a Leopard 1, and the driver trainer version of the Leopard 1 uses an 8.5 tonne weight to compensate for the lack of a turret. I don't know for sure what the M48's turret weight was, but I'm guessing around 3 tons since I've seen claims the M247 turret was 20 tons and it added 17 tons to the vehicle's weight. If the Gepard turret was 13.5 tonnes, that would make it approximately 15 tons, so it would add 12 tons to vehicle weight. It's certainly not a lightweight, but shaving 5 tons off the mass the M48's expected to haul around should help at least somewhat with the speed issue.

However, the M247 had plenty of other problems:
Electronics failures if it was wet
Hydraulic leaks if it was cold
Radar tracking degraded if it was warm
Too slow to engage (10-11s against hovering helicopters, 11-19s against moving targets, when the requirement was to engage within 8s)
Turret too slow to track fast targets
Lack of radar discrimination against ground clutter (most famously locking onto a latrine fan because the moving blades distracted it)
At high angles the gun barrels blocked the radar
Easily jammed
Gun range was half the range of the missiles carried by the helicopters it was supposed to engage


The range issue isn't really the design's fault, it's a failure of the requester to anticipate future technologies, but the development of longer-ranged anti-tank helicopter missiles meant that even if development had gone perfectly the utility of the design would have plummeted. It would still be useful against anything that blundered into its range, but the vehicles it was supposed to protect (not to mention the M247 itself) could be destroyed by a helicopter from well outside its own engagement range if it spotted them first. That range issue was why the Army shifted to missile-based AA for its next attempt at a fill-in-the-gap air defense vehicle (which turned out to be ADATS).

[CDAT]

All of the DIVAD entrants were based on the M48 hull (it was a proposal requirement), so that might have been a problem regardless of who won. I say might because I'm not sure the other entrants added as much weight as the M247 did (17 tons heavier than a normal M48). The Gepard's turret only adds 5 tonnes to a Leopard 1, and the driver trainer version of the Leopard 1 uses an 8.5 tonne weight to compensate for the lack of a turret. I don't know for sure what the M48's turret weight was, but I'm guessing around 3 tons since I've seen claims the M247 turret was 20 tons and it added 17 tons to the vehicle's weight. If the Gepard turret was 13.5 tonnes, that would make it approximately 15 tons, so it would add 12 tons to vehicle weight. It's certainly not a lightweight, but shaving 5 tons off the mass the M48's expected to haul around should help at least somewhat with the speed issue.

However, the M247 had plenty of other problems:
Electronics failures if it was wet
Hydraulic leaks if it was cold
Radar tracking degraded if it was warm
Too slow to engage (10-11s against hovering helicopters, 11-19s against moving targets, when the requirement was to engage within 8s)
Turret too slow to track fast targets
Lack of radar discrimination against ground clutter (most famously locking onto a latrine fan because the moving blades distracted it)
At high angles the gun barrels blocked the radar
Easily jammed
Gun range was half the range of the missiles carried by the helicopters it was supposed to engage


The range issue isn't really the design's fault, it's a failure of the requester to anticipate future technologies, but the development of longer-ranged anti-tank helicopter missiles meant that even if development had gone perfectly the utility of the design would have plummeted. It would still be useful against anything that blundered into its range, but the vehicles it was supposed to protect (not to mention the M247 itself) could be destroyed by a helicopter from well outside its own engagement range if it spotted them first. That range issue was why the Army shifted to missile-based AA for its next attempt at a fill-in-the-gap air defense vehicle (which turned out to be ADATS).

I do not remember where I found it, and will have to see if I can find it again, but I found an article written by a USAF pilot who was part of the testing of the SGt York. Not saying that it did not have issues (lots and lots of them), but from his prospective it worked, every time he tired to "attack" it shot him down, if I remember right it was 100% effective in the tests that he was part of. Could they have ever made it really work I do not think so, as to much was stacked against it from the get go, but in a TW2000 type world I could see maybe making some and saying what the heck it is better than nothing.

[Vespers War]

I do not remember where I found it, and will have to see if I can find it again, but I found an article written by a USAF pilot who was part of the testing of the SGt York. Not saying that it did not have issues (lots and lots of them), but from his prospective it worked, every time he tired to "attack" it shot him down, if I remember right it was 100% effective in the tests that he was part of. Could they have ever made it really work I do not think so, as to much was stacked against it from the get go, but in a TW2000 type world I could see maybe making some and saying what the heck it is better than nothing.

I'm pretty sure that was discussed in a previous thread, and I still hold the opinion that needing to hang four radar reflectors on a drone so the M247 could see it (as documented in reports on its shortcomings) suggests that either the pilot had extraordinarily bad luck in dealing with it, it had wildly variable performance, or the F-16 radar they kitbashed onto the M48 chassis was good at picking up high and fast aerial targets and sucked at NOE/pop-up target acquisition.