M247 Sergeant York: a Tester's View

GruntFox

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So, the subject of the Sergeant York SPAAG came up elsewhere and I remembered something from my original research onto SPAAG design (because popular consensus on the York is 'it is everything you must avoid for a SPAAG') for a few settings I'm working on. It was on Quora and, well, the guy who talked about the York had this to say:

Tom Farrier Retired USAF rescue helicopter pilot; current aviation safety contractor (UAS) said:
In 1982 I participated in both cooperative and non-cooperative tests at Aberdeen Proving Grounds in Maryland, flying an Air Force CH-3E helicopter against a Sergeant York. I would have been dead many times over had it been shooting live rounds at us instead of just video.

The Sergeant York was the front-runner in a program intended to provide the Army with a sorely needed “division air defense” (DIVAD) weapon system. It was based on a novel concept: re-purposing M48 Patton tank chassis’ with a new turret incorporating twin Swedish Bofors 40mm cannons and two radar systems — one for area surveillance (the rectangular antenna) and one for targeting (the conical antenna, an off-the-shelf application of the F-16′s radar).

A firing control system integrated the two radars, with on-board software prioritizing targets based on the threat they were assessed to pose to the system itself. (For the late ’70s /early ’80s, this was cosmic.) If the operator elected to allow the system to engage targets hands-off, it would slew the turret around at a nauseatingly rapid rate, taking on each in turn automatically.

On the next-to-last day of the test, my aircraft was joined by an Army AH-1 Cobra and OH-58 Kiowa and two Air Force A-10s. My H-3 was part of the test profile because its radar signature was essentially the same as that of an Mi-24 HIND assault helicopter of the day, which was heavily armed with both anti-tank missiles and rockets. We all converged on it simultaneously from about 6000 meters. My aircraft was the first to die, followed by the two A-10s, then the Cobra, and finally the Kiowa. It took less than 15 seconds to put plenty of hypothetical rounds into each of us.

I spent a depressing amount of that week watching myself get tracked and killed on video. Trying to “mask” behind anything other than rising terrain simply didn’t work; the DIVAD radar got a nice Doppler return off my rotor system if any part of it was within its line of sight, and it burned right through trees just fine. I couldn’t outrun or out-maneuver it laterally; when I moved, it tracked me. I left feeling pretty convinced that it was the Next Big Thing, especially since I’d come into the test pretty cocky thanks to having had a lot of (successful) exercise experience against current Army air defense systems.
So, what happened to the program itself? I think it was a combination of factors. First, the off-the-shelf concept was cool as far as it went, but the Patton design already was a quarter-century old; the DIVAD was awfully slow compared with the M1 Abrams tanks it was supposed to protect. It would have had a lot of trouble keeping up with the pack.

Second, The Atlantic Monthly published a really nasty article (bordering on a hatchet job) purporting to show the program was a complete failure and a ruinous waste of money. One of its most impressive bits of propaganda was an anecdote about a test where the system — on full automatic — took aim at a nearby trailer full of monitoring equipment. Paraphrasing, “It tracked and killed an exhaust fan,” chortled the author. (See The Gun That Shoots Fans for a recounting of this.)

Yeah, it did. It was designed to look for things that rotate (like helicopter main rotor systems) and prioritize them for prompt destruction. If any bad guys were on the battlefield in vehicles with unshrouded exhaust fans, they might have been blown away rather comprehensively. (My understanding at the time was that said fan was part of a rest room in one of the support vehicles and not a “latrine,” but why mess up a good narrative, right?)
To my knowledge, neither ventilated latrines nor RVs full of recording devices are part of a typical Army unit’s table of allowance, so I really doubt there was much of a fratricide threat there. However, the bottom line was that this particular piece of partisan reporting beat the crap out of a program that I believe the Army needed, but already was facing a few developmental issues, and helped hasten its cancellation.

(The New York Times opinion piece linked to above was equally laden with innuendo and assumptions. It made a fair point about possible anti-radiation attacks it might have invited… but there are radars on every battlefield, and there are means of controlling emissions. It compared a late-Fifties era Soviet system — the ZSU-23–4 — with one fully twenty years newer in design. It asserted that it couldn’t hit fixed-wing aircraft, which to my mind and personal observation was arrant nonsense. The only issue it raised that I agree with was possible NATO compatibility problems with the unique 40mm caliber shells the Sergeant York’s guns fired. Funny — the Times pontificated that it wouldn’t be cancelled, too. Oops.)

Third, the hydraulics that were used in the prototype were a 3000 psi system that really couldn’t handle the weight of the turret in its Awesome Hosing Things mode. One of the only times I actually got a score on the system was when I cheated; I deliberately exploited that vulnerability. I flew straight toward the system (which would have blown us out of the sky about twenty times over had I tried to do so for real) until directly over it, then tried to defeat the system from above.

If memory serves, the system specifications called for the guns to elevate to more than 85 degrees if something was coming up and over; it then would lower them quickly, slew the turret 180 degrees around, and raise the guns again to re-engage. It was supposed to be able to do that in perhaps ten seconds (but I’m here to tell you it did it a lot faster than that). So, I had my flight engineer tell me the moment the guns dropped, at which point I did a course reversal maneuver to try to catch it pointed the wrong way. What the video later showed was:
  1. Helicopter flies over.
  2. Traverse/re-acquire movement starts.
  3. Helicopter initiated hammerhead turn (gorgeous, if I say so myself).
  4. Guns started to elevate to re-engage.
  5. Clunk. Guns fall helplessly down; DIVAD crew uses bad language.
The hydraulics hadn’t been able to support the multiple close-on, consecutive demands of movement in multiple axes and failed. Like I said, I cheated. The Army and the contractors already knew about this problem and were going to fit out production models with a 5000 psi system. That might have had some survivability issues of its own, but the Army was perfectly happy that we’d done what we did — it proved the test wasn’t rigged and underscored the need for the production change.

Finally, the Army itself honestly appraised the system based on its progress (and lack of progress) versus their requirements. Wikipedia provides a passage that encapsulates this end-game well: “The M247 OT&E Director, Jack Krings, stated the tests showed, ‘...the SGT YORK was not operationally effective in adequately protecting friendly forces during simulated combat, even though its inherent capabilities provided improvement over the current [General Electric] Vulcan gun system. The SGT YORK was not operationally suitable because of its low availability during the tests.’ ”

I guess I’m forced to conclude that the Sergeant York was a really good concept with some definite developmental flaws — some recognized and being dealt with, perhaps one or two that would have made it less than fully effective in its intended role — that was expensive enough for bad PR to help bring it down before it fully matured. The Army was under a lot of political pressure to get it fielded, but to their credit they decided not to potentially throw good money after bad.

On balance, a lot of the contemporaneous criticisms mounted against the M247 really don’t hold up very well over time. Short-range air defense currently is provided by the latest generation of the AN/MPQ-64F1 Improved Sentinel system. Radar emitting on the battlefield? Check. Target prioritization capabilities? Check. Towed (which equals “slow”) versus self-propelled? Check.

I’m glad we never wound up in the position of needing it but not having it. My personal judgment was and is that it probably could have wound up a heck of a lot more capable and useful than its developmental history might suggest, but its cancellation probably was justified given other acquisition priorities at the time.

Bottom line: I repeatedly flew a helicopter against it over the course of many hours of testing, including coming at it as unpredictably as I knew how, and it cleaned my clock pretty much every time.
From what I understood about this is that it had some flaws, some of those flaws were being rectified, and all it really needed was 5k PSI hydraulics, slapped onto an M60 chassis, barrels that weren't simply worn out because some dumb idiot wanted to be a cheapskate and not order a few dozen 40mm barrels, tweak the fire control a bit more, and it would have been scaring the shit out of USSR helicopter pilots.

The York was designed to utilize a sensor-fused round that Bofors was putting into the market and due to the M42s being beloved by army troops during Vietnam, the US Army wanted a SPAAG that can do infantry support in a pinch.
 
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I got the impression that part of the issue was that the threat was changing. Longer-ranged anti-tank missiles, more helicopters. There may have been some mirror-imaging going on, it appears that Soviet doctrine differed from NATO in this regard.
 
As much as the US Army used the M48 chassis as a means of saving cost, could/would the M48-based Sgt York have been able to keep pase with the likes of the M1 and M2/3?

I'm also under the impression that the attempt to utilise a modified version of the Westinghouse AN/APG-66 from the GD F-16 Fighting Falcon.
I think the US Army had become somewhat gunshy with the notion of a start from scratch specialised scratch- design and built autonomous radar/fire-control system which was a nacesity for such an ambitious SPAAG system, that could engage aerial threats, whilst on the move. I'm of the opinion the US Army never got over their failings and criticism of their ambitious MIM-46 Mauler self-propelled battlefield SAM system. The fact that the US Army was not just prepared, but comfortable with a slapped together improvised 'Chaparral-Vulcan Air Defense System' before and after the Sgt York/"Division Air Defense" (DIVAD)d says loads to me how serious they were of battlefield air defence as part of their ORBAT.

Now the Soviet's had more than their fair share of terrible teething problems with their ZSU-23-4 "Shilka" SPAAG and 9K33 Osa self-propelled battlefield SAM system. But importantly, they persisted, and derived two world-class air defence systems, which have been tested and proven in numerous combat.
The Soviet's even went as far as totally redesigning the 9K33 Osa to fix it's original shortcomings.....And yet, the US Army threw in the towel.

Finally, the US Army should have utilised the longer-range and more accurate 35 mm Oerlikon KDA cannon instead of the legacy Bofors 40mm.


Regards
Pioneer
 
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Finally, the US Army should have utilised the longer-range and more accurate 35 mm Oerlikon KDA cannon instead of the legacy Bofors 40mm
Remember that this was an era when Bofors was offering a proximity-fuzed 40mm, while 35mm AHEAD was still decades in the future. At that moment, with that tech on offer, I'd say 40mm was clearly a better solution.
 
As much as the US Army used the M48 chassis as a means of saving cost, could/would the M48-based Sgt York have been able to keep pase with the likes of the M1 and M2/3?

I'm also under the impression that the attempt to utilise a modified version of the Westinghouse AN/APG-66 from the GD F-16 Fighting Falcon.
I think the US Army had become somewhat gunshy with the notion of a start from scratch specialised scratch- design and built autonomous radar/fire-control system which was a nacesity for such an ambitious SPAAG system, that could engage aerial threats, whilst on the move. I'm of the opinion the US Army never got over their failings and criticism of their ambitious MIM-46 Mauler self-propelled battlefield SAM system. The fact that the US Army was not just prepared, but comfortable with a slapped together improvised 'Chaparral-Vulcan Air Defense System' before and after the Sgt York/"Division Air Defense" (DIVAD)d says loads to me how serious they were of battlefield air defence as part of their ORBAT.

Now the Soviet's had more than their fair share of terrible teething problems with their ZSU-23-4 "Shilka" SPAAG and 9K33 Osa self-propelled battlefield SAM system. But importantly, they persisted, and derived two world-class air defence systems, which have been tested and proven in numerous combat.
The Soviet's even went as far as totally redesigning the 9K33 Osa to fix it's original shortcomings.....And yet, the US Army threw in the towel.

Finally, the US Army should have utilised the longer-range and more accurate 35 mm Oerlikon KDA cannon instead of the legacy Bofors 40mm.


Regards
Pioneer
From my understanding, the M48 was only chosen because the M60 was still the mainline tank at the start of the program. Then the M1 arrived. If I was able to be leading the program, one of the changes I would do (other than upgrading the hydraulics to 5k PSI units instead of the 3k) would swap the chassis. At least the M60 can keep up.
As much as the US Army used the M48 chassis as a means of saving cost, could/would the M48-based Sgt York have been able to keep pase with the likes of the M1 and M2/3?

I'm also under the impression that the attempt to utilise a modified version of the Westinghouse AN/APG-66 from the GD F-16 Fighting Falcon.
I think the US Army had become somewhat gunshy with the notion of a start from scratch specialised scratch- design and built autonomous radar/fire-control system which was a nacesity for such an ambitious SPAAG system, that could engage aerial threats, whilst on the move. I'm of the opinion the US Army never got over their failings and criticism of their ambitious MIM-46 Mauler self-propelled battlefield SAM system. The fact that the US Army was not just prepared, but comfortable with a slapped together improvised 'Chaparral-Vulcan Air Defense System' before and after the Sgt York/"Division Air Defense" (DIVAD)d says loads to me how serious they were of battlefield air defence as part of their ORBAT.

Now the Soviet's had more than their fair share of terrible teething problems with their ZSU-23-4 "Shilka" SPAAG and 9K33 Osa self-propelled battlefield SAM system. But importantly, they persisted, and derived two world-class air defence systems, which have been tested and proven in numerous combat.
The Soviet's even went as far as totally redesigning the 9K33 Osa to fix it's original shortcomings.....And yet, the US Army threw in the towel.

Finally, the US Army should have utilised the longer-range and more accurate 35 mm Oerlikon KDA cannon instead of the legacy Bofors 40mm.


Regards
Pioneer
You've also got to understand that Congress has the purse strings and had various laws kitted to make such an avenue largely locked out. Also, 35mm guns are, um, poor, to say the least when it comes to anti-air work. Not only that but you've got the USAF in many of a politician's ears, making it harder for the US Army to get AAA systems. The only reason that the USN isn't a completely dilapidated mess is that the USN has a lot more pull thanks to it existing since the US was born. Basically, the similar situation Britain has when it comes to procurement (i.e. screw the army, only the navy and airforce only matters).

Bofors's 40mm HEPF is a revolutionary (and still is) round. Remember, before Bofors came out of this round, the smallest caliber of weapon was 75mm.
Finally, the US Army should have utilised the longer-range and more accurate 35 mm Oerlikon KDA cannon instead of the legacy Bofors 40mm
Remember that this was an era when Bofors was offering a proximity-fuzed 40mm, while 35mm AHEAD was still decades in the future. At that moment, with that tech on offer, I'd say 40mm was clearly a better solution.
This. That and the guns used are the older L/60s and not the newer L/70s (also, the barrels in the program were completely worn out...).
 
Finally, the US Army should have utilised the longer-range and more accurate 35 mm Oerlikon KDA cannon instead of the legacy Bofors 40mm
Remember that this was an era when Bofors was offering a proximity-fuzed 40mm, while 35mm AHEAD was still decades in the future. At that moment, with that tech on offer, I'd say 40mm was clearly a better solution.
I respectively recognise your thoughts and opinion, my dear TomS.

Regards
Pioneer
 
Finally, the US Army should have utilised the longer-range and more accurate 35 mm Oerlikon KDA cannon instead of the legacy Bofors 40mm
Remember that this was an era when Bofors was offering a proximity-fuzed 40mm, while 35mm AHEAD was still decades in the future. At that moment, with that tech on offer, I'd say 40mm was clearly a better solution.
I respectively recognise your thoughts and opinion, my dear TomS.

Regards
Pioneer
It should be noted that the DIVAD program had two 35mm entries, one that is essentially an American Gepard, and a rechambered Vigilante (aka Sprey and Company's 37mm-would-vibrate-itself-to-pieces-from-recoil-alone system.

The 35mm was deemed -and would still be deemed- not lethal enough. Especially since the US Army also wants some infantry fire support capability (something that the M42 was well-liked for).
 
Putting it on an M-60 hull would have been the best way to go.
But I am sceptical about "keeping up" with the M-1 would have been a serious problem in most combat scenarios. NATO tank formations would have been used largely for defensive manoeuvres in Europe for the first part of any Warpac invasion scenario. Even in counter-attack scenarios tanks move in leaps covered by others within the formation, no-one was going to drive full-tilt into belts of waiting Soviet ATGWs and guns and tanks like it was 1941 all over again. Let's not forget the Shikla only did around 19-20mph over rough ground, though the Tunguska chassis is quicker.
 
The Army and the contractors already knew about this problem and were going to fit out production models with a 5000 psi system.

I don't doubt most of this story but this almost certainly isn't true.
Here's the thing, that's in line with what happened to the AH-56 before it got canned. A lot of the problems that were coming up had solutions but got canceled before implementation.
Putting it on an M-60 hull would have been the best way to go.
But I am sceptical about "keeping up" with the M-1 would have been a serious problem in most combat scenarios. NATO tank formations would have been used largely for defensive manoeuvres in Europe for the first part of any Warpac invasion scenario. Even in counter-attack scenarios tanks move in leaps covered by others within the formation, no-one was going to drive full-tilt into belts of waiting Soviet ATGWs and guns and tanks like it was 1941 all over again. Let's not forget the Shikla only did around 19-20mph over rough ground, though the Tunguska chassis is quicker.
True.
 
The Army and the contractors already knew about this problem and were going to fit out production models with a 5000 psi system.

I don't doubt most of this story but this almost certainly isn't true.
Here's the thing, that's in line with what happened to the AH-56 before it got canned. A lot of the problems that were coming up had solutions but got canceled before implementation.

Here's what thing? A 5000 psi hydraulic system isn't a solution to anything in an armored vehicle, especially in the early 80s. It's not even more powerful, that's not how hydraulics work. The problem in the ITP's hydraulic system was leakage, not power. If the guns suddenly drop down it's because there's a leak and the hydraulic system has lost pressure. By the way, the 1982 tests were so bad the Army concluded the prototype was unsuited for further testing.

Sgt. York's failures were nothing like the AH-56. They came almost entirely from the Army using a novel acquisition model with acknowledged risks on a complex project. All this is well-documented.

The vehicle itself may not have been entirely the disaster it's been portrayed as, but the program itself certainly was.
 
Tfw the rubber seals or whatever can't handle 3000 psi and blow themselves out doing something as basic as elevating the gun.

Once the US Army got rid of the Railway Grand Divisions they had to use something else for all the trainwrecks and I guess ADA was just vibing.
 
Finally, the US Army should have utilised the longer-range and more accurate 35 mm Oerlikon KDA cannon instead of the legacy Bofors 40mm
Remember that this was an era when Bofors was offering a proximity-fuzed 40mm, while 35mm AHEAD was still decades in the future. At that moment, with that tech on offer, I'd say 40mm was clearly a better solution.
I respectively recognise your thoughts and opinion, my dear TomS.

Regards
Pioneer
It should be noted that the DIVAD program had two 35mm entries, one that is essentially an American Gepard, and a rechambered Vigilante (aka Sprey and Company's 37mm-would-vibrate-itself-to-pieces-from-recoil-alone system.

The 35mm was deemed -and would still be deemed- not lethal enough. Especially since the US Army also wants some infantry fire support capability (something that the M42 was well-liked for).
I remember there's 3 different 35mm plan.
Sperry&Rand rechambered Vigilante
Raytheon Gepard turret
s-l1000 (1).jpg
and General Dynamics T246
This prototype got better result in firing trial than Ford T247
 
Finally, the US Army should have utilised the longer-range and more accurate 35 mm Oerlikon KDA cannon instead of the legacy Bofors 40mm
Remember that this was an era when Bofors was offering a proximity-fuzed 40mm, while 35mm AHEAD was still decades in the future. At that moment, with that tech on offer, I'd say 40mm was clearly a better solution.
I respectively recognise your thoughts and opinion, my dear TomS.

Regards
Pioneer
It should be noted that the DIVAD program had two 35mm entries, one that is essentially an American Gepard, and a rechambered Vigilante (aka Sprey and Company's 37mm-would-vibrate-itself-to-pieces-from-recoil-alone system.

The 35mm was deemed -and would still be deemed- not lethal enough. Especially since the US Army also wants some infantry fire support capability (something that the M42 was well-liked for).
I remember there's 3 different 35mm plan.
Sperry&Rand rechambered Vigilante
Raytheon Gepard turret
View attachment 660855
and General Dynamics T246
This prototype got better result in firing trial than Ford T247
The contestants that I remember is GE's (which is, oddly enough, a GAU-8 in a turret mated with the radar set), the Vigilante that got rechambered (aka Sprey and Company's design), the Ford design (aka the Sgt. York), and the GD design (shown above).

The core thing about the Sgt. York was that 40mm HE was really good in fire support for its size, to the point that US Army troops that had their M42s almost used HE exclusively.
 
Couple pictures of the other entrants that I've run across:

Concept art for the redesigned Sperry 35mm Vigilante
divad37mmvigilantebz8.jpg

The original Sperry T249 Vigilante as designed in the late '50s, with the 37mm Gatling gun on a stretched M113 chassis
Gatling_Tank_by_PrinzEugn.jpg
vigilante 1.jpg vigilante 2.jpg ZOFrOFI.jpg

And the most interesting of the bunch, GE's GAU-8 on an M48 chassis
gau8divadij7.jpg
tumblr_otho2k3cAj1qbpemno1_1280.jpg

Oh, and just for some extra neatness, the Swedish attempt at the DIVAD (that I believe was working in conjunction with the US on the 40mm L/70 Bofors proximity-fuzed system), the VEAK 40 based on the Strv 103 "S-Tank" and only heard of for appearing in War Thunder when the Swedish ground vehicle tree was added. For obvious enough reasons, it very quickly earned the nickname "Sergeant Björk".
a91e55623b7bbd7798c7fd44d541aeb8.png
 
You also got to remember that the Vigilante had a disturbing tendency to literally shake itself apart in its original configuration, largely due to the recoil of the 37mm being so harsh.
 
You also got to remember that the Vigilante had a disturbing tendency to literally shake itself apart in its original configuration, largely due to the recoil of the 37mm being so harsh.

This is the one you've said twice was made by "Sprey and Company?" What original configuration? 37x255mm? 37x217mm?
 
Given the continued development of helicopter-launched ATGMs a vehicle like the Sergeant York would eventually have to operate in a close pairing with a missile-based forward SHORAD vehicle like the later ADATS. If you recognize this fact does the picture change to favor the smaller caliber faster firing cannons like the GAU-8/A?

I'd love to hear more about how the Vigilante performed. Unless I'm mistaken that's the largest caliber modern Gatling-type gun built.
 
This kinda makes me think... i wonder if there is any stories on the XM-246, the one which based on Phalanx. I heard it fares better but no more than that.
 
Given the continued development of helicopter-launched ATGMs a vehicle like the Sergeant York would eventually have to operate in a close pairing with a missile-based forward SHORAD vehicle like the later ADATS. If you recognize this fact does the picture change to favor the smaller caliber faster firing cannons like the GAU-8/A?

I'd love to hear more about how the Vigilante performed. Unless I'm mistaken that's the largest caliber modern Gatling-type gun built.

Gatling guns aren't that important, but the GE Blazer turret exists I guess. The ideal air defense system in the sort of environment envisioned by the US Army would be a combination of a 25mm cannon mated to a Roland launcher or something. Roland is pretty high performance shot-per-shot as far as air defense vehicles go and it's fairly cheap, and the 25mm covers its dead zone, so they complement each other well.

ADATS was a mistake but only because it tried to do too much at once for no real gain. A smaller missile with a laser guidance mode (BOLIDE maybe) would be pretty nice but that didn't exist at the time.

Given how quickly the air defense environment had changed, the US Army not buying any air defense vehicles was actually more of a blessing than anything. Putting an Iron Dome launcher on a Bradley chassis would probably be the way forward today, since it's also a proven air defense system against the kinds of threats the US Army faces (stray mortar bombs and short range ballistic rockets). OTOH Iron Dome won't do anything against IRBMs like Iran shot at America so its utility is dubious at best against someone with big missiles as opposed to glorified sugar rockets made in a garage.
 
Given the continued development of helicopter-launched ATGMs a vehicle like the Sergeant York would eventually have to operate in a close pairing with a missile-based forward SHORAD vehicle like the later ADATS. If you recognize this fact does the picture change to favor the smaller caliber faster firing cannons like the GAU-8/A?

I'd love to hear more about how the Vigilante performed. Unless I'm mistaken that's the largest caliber modern Gatling-type gun built.
Not really. Aircraft were getting hardened against small-caliber autocannon up to the 35mm range. 40mm or more are becoming the requirement. Even Russia is investing in large-caliber autocannons...
This kinda makes me think... i wonder if there is any stories on the XM-246, the one which based on Phalanx. I heard it fares better but no more than that.
Not really. From what I understand 20mm was way too impudent in the role that it was going to be thrown in, at least in this case. 20/23mm autocannon was just becoming obsolete during this time, mind you. They simply didn't have enough 'omph'.
 
This kinda makes me think... i wonder if there is any stories on the XM-246, the one which based on Phalanx. I heard it fares better but no more than that.
Not really. From what I understand 20mm was way too impudent in the role that it was going to be thrown in, at least in this case. 20/23mm autocannon was just becoming obsolete during this time, mind you. They simply didn't have enough 'omph'.

Impudent????

XM-246 fire control was based on Phalanx, not the guns. They were 35mm Oerlikons firing proximity-fused shells. If you'd do at least basic research on DIVAD this thread wouldn't be full of youtube comment quality hogwash.

This. That and the guns used are the older L/60s and not the newer L/70s (also, the barrels in the program were completely worn out...).

And by basic research I mean the most basic imaginable.
 
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This kinda makes me think... i wonder if there is any stories on the XM-246, the one which based on Phalanx. I heard it fares better but no more than that.

I mean, Centurion exists and M247 was probably the last time anyone thought APG-66 would be good for a ground mount.

That said DIVAD using worn out M48 hulls ripped from SIAD or whatever when the Army was busy buying M1s and M2s probably tells you everything you need to know.
 
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Was any thought given to replacing the M247 Sergeant York's problematic Westinghouse AN/APG-66 derived tracking radar with an alternate radar system?
 
"A 5000 psi hydraulic system isn't a solution to anything in an armored vehicle, especially in the early 80s. It's not even more powerful, that's not how hydraulics work. The problem in the ITP's hydraulic system was leakage, not power. If the guns suddenly drop down it's because there's a leak and the hydraulic system has lost pressure."

- drejr, 2021

Thank you for the technical explanation, for as much as Tom Farrier mentioned it, would be nice to elaborate what he meant by "That might have had some survivability issues of its own,...."


"Sgt. York's failures were nothing like the AH-56. They came almost entirely from the Army using a novel acquisition model with acknowledged risks on a complex project."

-drejr, 2021

So do I interpret what you are saying is the US Army was being overly ambitious with its operational requirements for both
the M247 and AH-56 from the getgo?

Sadly GruntFox, the M163 and 20mm M61 that it was built on was yet another improvisation, an improvisation that the U.S. Army never remedied, until it itself was finally phase-out without a real replacement in the end. Granted, I wouldn't have wanted to get a face full of a M61 burst, but it's characteristics were and always were very limited in terms target engagement range, velocity.

Regards
Pioneer
 
Was any thought given to replacing the M247 Sergeant York's problematic Westinghouse AN/APG-66 derived tracking radar with an alternate radar system?
The thing was that the problem is with... fine-tuning the radar and the FCS system with it. Remember, this was a significant breakthrough in SPAAG tech as the radar was designed to be basically 'if it is radar-opaque, then LoS answer is yes', and this was on top of the HEPF rounds being offered. For helicopters, this is absolutely deadly, as it means they can't just hide behind some trees and do 'pop up' attacks. That's why helicopter doctrine has shifted from their original doctrines to, effectively, 'stay behind the allied side of the frontline and spam indirect missiles at the enemy', the battlespace has made 'low and slow' to be deadly against anyone semi-competent.
 
They remedied the loss of DIVAD with Stinger, which was much less involved to deploy.

Sgt. York was a great name, and building around Bofors 40 was sound. But it's just an overly expensive remedy to a mission solved through technology. If it could have been mounted on a cheap chassis like M113, it had more chance. Did it really need twin guns, too? And they certainly did not need a multi-million dollar fighter radar to solve the 'helicopters behind trees and obstacles' problem. They just went too aggressive with their solution.
 
It is interesting that the British Army never deployed the Falcon AA system and relied on Blowpipe and Rapier.
There is little experience of how effective Gepard for example would have been. Only the ZSU family have any actual combat experience.
The IDF had the Chaparral and M163 Vulcan that was the US Army solution between the 60s and 1990. Is there any account of how they performed?
 
You also got to remember that the Vigilante had a disturbing tendency to literally shake itself apart in its original configuration, largely due to the recoil of the 37mm being so harsh.

This is the one you've said twice was made by "Sprey and Company?" What original configuration? 37x255mm? 37x217mm?
Should be "Sperry" not "Sprey". Funny factoid is through all the subsequent acquisitions they're now L-3 Harris and there are still old pictures of the Vigilante on the walls over there.
 
This has been a fascinating thread. I thought it was only the British who cobbled stuff together then struggled to get it to work.

SPAAGS are quite fascinating, especially in the SPAAG gun/attack helicopter ATGW race.

Chris
 
The IDF had the Chaparral and M163 Vulcan that was the US Army solution between the 60s and 1990. Is there any account of how they performed?
Heyl ha Avir's Chaparrals scored one Syrian MiG-17, which IIRC is the single world-wide kill by a MIM-72.

The M163 Hovet are credited with three victories, against Syria during op shalag in 1982.
They haven't had many other opportunities to defend against air attack since.

They have actually been used more in urban fighting, where their high elevation is useful to flush out foes hiding in the upper floors, without having to collapse the whole building.
 
They remedied the loss of DIVAD with Stinger, which was much less involved to deploy.

Sgt. York was a great name, and building around Bofors 40 was sound. But it's just an overly expensive remedy to a mission solved through technology. If it could have been mounted on a cheap chassis like M113, it had more chance. Did it really need twin guns, too? And they certainly did not need a multi-million dollar fighter radar to solve the 'helicopters behind trees and obstacles' problem. They just went too aggressive with their solution.
Here's a little factoid: you must have a radar on an AAG, or it's useless other than 'when aircraft are right on top of you'. This was as obvious as far back as WW2, mind you.

The M113 was still in use and was already slated for a few dozen things already... alongside the fact that it has quite a few limitations (the Vigilante was built on an M113 chassis, and the recoil of the gun basically wrecked the chassis).

Two guns were because the 40mm Bofors weren't as quick firing as the 35mm guns... and want to have the option of sending a lot of lead down-range if needed.
 
Strange the chassis of M113 couldn't handle the shock considering a pair of 40's worked on an M41 chassis and Brazil (e.g. Charrau) did it on an extended M113 chassis. My very concern was the rate of fire for the opposite reason. You can only load so much up to fire. They tried a 37mm T250 in the T249 vehicle and it burnt through its drum real fast at anti-aircraft rates. In the ground role its rof was about same as the 40mm Bofors. The T250 on the T249 was a rotary, like the Vulcan, only in 37x219, with a 192-round drum, so you can imagine at 3,000 rounds a second you better be aiming where you mean it. Bofors in comparison was 40x365 of L70 and 40x311 of the L60. The twin was simply too heavy on a vehicle to react against helicopters and jets. Its my opinion that reaction time also needed to be cut down under 4 seconds to be useful, and the twin was not getting there. Today, with Link16, I don't imagine that would be as much of a problem against threats identified soon enough to pre-aim.

And btw- my beef wasn't that it had radar. My beef was them trying to sell too much radar for the role.
 
And btw- my beef wasn't that it had radar. My beef was them trying to sell too much radar for the role.
Thing was, that radar was the one they could get 'off the shelf' aka readily available. :rolleyes: Also, it had responsiveness, but the problem is that said responsiveness had two problems: it would overload the 3k PSI hydraulics in certain situations, and the speed of the turret was considered 'nauseating'.
 
It is interesting that the British Army never deployed the Falcon AA system and relied on Blowpipe and Rapier.
Its the Marksman one that is even more puzzling...developed just after we realised that close in defence might need guns as well...no orders, then the Cold War drawdown arrived..
 
Maybe they should just approach future SPAAG as an army CIWS. Instead of trying to reach long ranges they should be thinking about protecting a force under artillery attack or from hostile guided bombs while on the move at 35-45 mph. Can you do that with a DIVAD type of system, with its directional radar linked to share information with something using LINK16, or do you need spherical radar coverage? And if you use radar coverage, would you draw more fire than defend against? Would hate to be broadcasting your position in this highly dangerous environment.
 
Maybe they should just approach future SPAAG as an army CIWS. Instead of trying to reach long ranges they should be thinking about protecting a force under artillery attack or from hostile guided bombs while on the move at 35-45 mph. Can you do that with a DIVAD type of system, with its directional radar linked to share information with something using LINK16, or do you need spherical radar coverage? And if you use radar coverage, would you draw more fire than defend against? Would hate to be broadcasting your position in this highly dangerous environment.
Here's the thing, as far as I know, only Shilka (ZSU-23-4) crews were trained to do something like that, and even then, that was only against PGMs and only when they could catch them. It wasn't until the late '80s/early '90s that the capability actually started showing up.
 
A GAU-8 on an Abrams chassis and lots of ammo.
However, that would go against the fire support requirement, as the M42 Duster showed that 40mm HE is surprisingly good. Don't forget that battery fires are a thing, and they're nasty (which is what you'll need when using the damn thing), especially when considering the power consumption that the GAU-8 had. In comparison, the battery packs for the radar and whatnot are cheap change.
 
The most sensible, effective and cost efficient solution was the Gepard turret (including sensors and 35mm guns) on the M1 chassis - period.

Regards
Pioneer
 
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