US Army's mobile howitzer "shoot off"

[Dawes]

Not familiar with the Serbian entry. Is it considered competitive with the others?

U.S. Army mobile howitzer shoot-off participants emerge (defensenews.com)

[shep854]

They seem to be moving rather briskly.

[bojan]

From few very hushed whispers I have heard it will not be NORA B-52 It looks like MGS-25 prototype might be sent.

[Adam Peter]

Why it is divided when the tube locks the two parts into one?

[Mighty_Zuk]

I don't think the Serbian entry has a chance here, frankly. 

The other 4 contenders have a real shot here, with AM General perhaps being the least preferred other than Yugoimport.

Nexter Caesar - in service with 2 NATO allies including 1 major NATO ally (France). However it lacks full auto loading and no roadmap for such an option has been disclosed. Goes for light, stripped down approach of only maintaining core functions.

BAE Archer - very limited service but exists for quite a while, is ready, and has apparently optimized shoot and scoot sequence. Using MAN truck but otherwise not much details.

Elbit Iron Saber - not operational within NATO but has the highest range of options for the US to choose from, plus is setting up domestic production. Will go for heavier 8x8 system AFAIK, but will avoid complex recoil reduction systems for now.

AM General Brutus - potentially revolutionary recoil management system, but otherwise the system is missing a lot based on the last seen variant.

 

[bojan]

1 hour ago, Mighty_Zuk said:

I don't think the Serbian entry has a chance here, frankly. ...

No shit Sherlock.

OTOH, even just wanting to evaluate it is an interesting thing.

 

Quote

AM General Brutus - potentially revolutionary recoil management system, but otherwise the system is missing a lot based on the last seen variant.

Go visit a local museum, you have examples of "revolutionary recoil management system" in Yad Mordechai:

Or in 1904:

Edited December 18, 2020 by bojan

[bojan]

 

2 hours ago, Adam Peter said:

Why it is divided when the tube locks the two parts into one?

Truck chassis is not divided, it is based on modular concept where it can be applied to a wide variety of the trucks (KAMAZ, MAN, local FAP/Mercedes etc). IOW, cabin and gun module are the thing, truck can be any one you want as long as it fills broad technical specifications.

Edited December 18, 2020 by bojan

[sunday]

Middle outriggers need those cuts on the body that make the truck frame to look divided.

[EchoFiveMike]

The word is articulated.  Like the Archer.  It looks to me as if this truck is simply twin steer on the front 2 axles.  S/F....Ken M

[bojan]

It is a standard MAN 8x8, as used on ATMOS, with strengthened frame.

Articulated does poorly when firing at full charge at higher elevations, articulation tends to fail due the bending of the chassis.

Edited December 18, 2020 by bojan

[Mighty_Zuk]

3 hours ago, bojan said:

No shit Sherlock.

OTOH, even just wanting to evaluate it is an interesting thing.

No need to be rude. If they're sending their system for the shoot-off, someone must see the economical viability in this.

3 hours ago, bojan said:

Go visit a local museum, you have examples of "revolutionary recoil management system" in Yad Mordechai:

Or in 1904:

Could not find info on the second (Turkish?) gun, but the 65mm Mle 1906 had a recoil system using hydraulics and springs. What was your point exactly?

Just because one system uses a damping mechanism, doesn't mean every other damping mechanism in the world uses the same, unless you're willing to argue every vehicle uses the same suspension type.

The recoil mechanism I am talking about is FOOB - Fire Out Of Battery. 

It works by the principle of accelerating the gun forward to an optimal point in which an ignition would merely push the gun back to its starting position without a kickback effect. Or in non-ideal systems, a substantially reduced kick. That's how AM General has been able to fire a 155mm howitzer from a barely modified flatbed truck without digging into the ground, and do so similarly with a 105mm howitzer on an old HMMWV.

[Dawes]

Even if the Serbian entry doesn't win, I would think that just participating raises it's visibility to other potential customers.

[bojan]

1 hour ago, Mighty_Zuk said:

....The recoil mechanism I am talking about is FOOB - Fire Out Of Battery....

 

Which both 65mm Mle1906 mountain gun and 155mm Mle1904TR howitzer pictured above had. Both were French. All of the above is less than a 5 minute google search. Yet you ignored it, because you swallow marketing buzzwords like "revolutionary new system" hook, line and sinker, w/o really understanding what is behind it.

Sorry for sounding rude, but when I see "revolutionary" attached to any military hardware I have a strong urge to throw. Especially if it is something that was more than 100 years old idea.

 

Edited December 18, 2020 by bojan

[bojan]

11 minutes ago, Dawes said:

Even if the Serbian entry doesn't win, I would think that just participating raises it's visibility to other potential customers.

Sales of NORA B-52 have been going reasonably well, with Cyprus being a latest customer (24 ordered, 12 IIRC delivered so far). MGS-25 is a next step, with 25l vs 23l chamber, improved autoloader and fully autonomous gun module, resulting in only 3 crew needed (vs 5 for NORA). Even autoloader reloading is automated (from a smooth-sided box at the rear of the front module), which can also be automatically loaded from an ammunition truck.

But as you have noted, just participating in this is a huge marketing boost.

Edited December 18, 2020 by bojan

[CaptLuke]

2 hours ago, bojan said:

Which both 65mm Mle1906 mountain gun and 155mm Mle1904TR howitzer pictured above had. Both were French. All of the above is less than a 5 minute google search. Yet you ignored it, because you swallow marketing buzzwords like "revolutionary new system" hook, line and sinker, w/o really understanding what is behind it.

Sorry for sounding rude, but when I see "revolutionary" attached to any military hardware I have a strong urge to throw. Especially if it is something that was more than 100 years old idea.

 

Also the much later, but in the US,  XM-204 105mm Howitzer.  They called it "soft recoil" but the principal was FOOB.

There's a video (which goes into detail about how the new and amazing FOOB works) here.

 

[JasonJ]

About the paragraph in the article that mentions possible offerings from Hanwha and Mitsubishi.. Hanwha, the maker of the K9 arty, doesn't have a wheeled arty product. Neither does Mitsubishi but the Type 19 8x wheeler arty is made by Japan Steel Works. 

[Mighty_Zuk]

Hmm, thanks. I was educated. However, I do know that even old concepts get renewed with brand new tech at times to get a new level of effect, or address an emerging issue that becomes relevant as systems become more complex. I'll try to do more research.

[shep854]

About every trick in both artillery and small arms was tried by the early 20th century.  Now it's tinkering and materials.

[wendist]

A language question for you guys. Does the phrase below literally mean that you have to use 18 guns (artillery pieces, vehicles, call it whatever you want) in this shoot-out?

"Participants must provide 18 evaluation systems for the event, according to the solicitation"

I'm asking because:

A: I'm not a native english speaker.

B: The number sounds excessive to me, if all you are going to do is a test.

Please help me out here guys.

[Dawes]

To me , that would suggest providing 18 guns for the test. Unless "evaluation systems" means other pieces of equipment related to the system.

Edited December 19, 2020 by Dawes

[bojan]

There are more about it, this shootout is single gun. Then selected one provides additional two for testing (IIRC until the end of 2021) and further 18 for adoption in 24 months starting in 2023 or 2024.

Edited December 19, 2020 by bojan

[bojan]

2 hours ago, shep854 said:

About every trick in both artillery and small arms was tried by the early 20th century.  Now it's tinkering and materials.

And additionally precision of manufacture did not really improve in the last 100 years. High precison work at the modern level was possible pre WW1 at least, it is just a thing that it is now way, way cheaper to do in large quantities.

PS. second howitzer of the two, 155mm Mle 1904TR was very advanced for it's time. Barrell was pulled back before first shot, tray for round would pop up, projectile and charge were placed on tray and when lever was pulled both projectile and charge were rammed automatically, breach was closed, barrel started going forward and shot was fired. After recoil barrel stayed in the rear position, tray popped up and all the crew needed to do was to place projectile and charge on the tray. This enabled extremely high RoF of 15 RPM. IOW, more advanced than most guns coming after it, just obscenely expensive to produce at the time, which is one of the reasons it was replaced by much simpler guns. Other reason was inherent to all guns with this recoil mechanism and I am not sure if it is solvable even today - increased dispersion. It was not a big deal with short ranges those two examples had, but with modern 155/52 barrel and 30+km range it is going to show.

 

Edited December 19, 2020 by bojan

[Mighty_Zuk]

3 hours ago, bojan said:

And additionally precision of manufacture did not really improve in the last 100 years. High precison work at the modern level was possible pre WW1 at least, it is just a thing that it is now way, way cheaper to do in large quantities.

PS. second howitzer of the two, 155mm Mle 1904TR was very advanced for it's time. Barrell was pulled back before first shot, tray for round would pop up, projectile and charge were placed on tray and when lever was pulled both projectile and charge were rammed automatically, breach was closed, barrel started going forward and shot was fired. After recoil barrel stayed in the rear position, tray popped up and all the crew needed to do was to place projectile and charge on the tray. This enabled extremely high RoF of 15 RPM. IOW, more advanced than most guns coming after it, just obscenely expensive to produce at the time, which is one of the reasons it was replaced by much simpler guns. Other reason was inherent to all guns with this recoil mechanism and I am not sure if it is solvable even today - increased dispersion. It was not a big deal with short ranges those two examples had, but with modern 155/52 barrel and 30+km range it is going to show.

 

It has less to do with manufacturing precision. 

For example, a tank's FCS acquires a target and follows it until you shoot. There's a certain non-zero time that passes between pulling the trigger and the ignition, or when the projectile leaves the barrel (you choose the reference point).

I've read it in some study that compared ETC and other exotic guns with conventional ones, and cited the innate long delay in conventional guns as a source of inaccuracy against moving targets.

I do not understand exactly why it is a source of inaccuracy. I may have forgotten, or it may not have been written, but it could be fixed by simply actively tracking the target even up to several miliseconds after you pull the trigger. But many may not do that and just halt tracking when the trigger is pulled. Of course, it makes sense to reduce the time of tracking, to reduce the toll on the stabilizers, but that's a bit much IMO.

But in cases where simply a lead is calculated plus the optimal time to shoot, this delay becomes a significant factor. If it's very predictable and always roughly the same, you can just remove it in a calibration process. But if there's a big enough margin of error, it could be a problem. Maybe not in today's tanks, but it may be relevant for air defense missions for artillery (as the US Army clearly showed an interest in such capability). 

Just another case of old tech trying to stay relevant.

[sunday]

4 minutes ago, Mighty_Zuk said:

It has less to do with manufacturing precision. 

For example, a tank's FCS acquires a target and follows it until you shoot. There's a certain non-zero time that passes between pulling the trigger and the ignition, or when the projectile leaves the barrel (you choose the reference point).

I've read it in some study that compared ETC and other exotic guns with conventional ones, and cited the innate long delay in conventional guns as a source of inaccuracy against moving targets.

I do not understand exactly why it is a source of inaccuracy. I may have forgotten, or it may not have been written, but it could be fixed by simply actively tracking the target even up to several miliseconds after you pull the trigger. But many may not do that and just halt tracking when the trigger is pulled. Of course, it makes sense to reduce the time of tracking, to reduce the toll on the stabilizers, but that's a bit much IMO.

But in cases where simply a lead is calculated plus the optimal time to shoot, this delay becomes a significant factor. If it's very predictable and always roughly the same, you can just remove it in a calibration process. But if there's a big enough margin of error, it could be a problem. Maybe not in today's tanks, but it may be relevant for air defense missions for artillery (as the US Army clearly showed an interest in such capability). 

Just another case of old tech trying to stay relevant.

You may have ETC, the finest digital fire control, and the works. You may even have a fricking laser gun. However, if the barrel plus chamber assembly is travelling inside the mount at the time of firing there will be increased dispersion because there is another source of error, i.e. it is not straightforward to make a system that will ignite always at the same position of travel, and at the same travel velocity.

[bojan]

Timing ignition is a less of the issue. If the barrel moves during firing there have to be tollerances. Even if those are 1mm for a length of the L/52 barrel (8m), calculate how much is that at 32+km. And it is going to be more than 1mm tollerance, else mechanism will seize in extreme heat/cold.

More variables you add, less you are in the control of the situation. Some things (modern recoil mechanisms) are there because things are just inconvenient w/o them, but from the accuracy perspective, the more you move from a totally fixed barrel the more you are in the problem.

It is a great idea for a light howitzers firing at ~10km. For something that people want to fire at 40+km... It just brings problems, w/o really doing anything fundamental. Who really cares that lightter vehicle can be used for it, if it is brigade level, 40+km ranged arty and it still needs shitloads of heavy trucks just to bring it ammo?

Edited December 19, 2020 by bojan