Andrew Jaremkow

Out of curiosity I plotted the velocity curves for a number of full caliber fin stabilised projectiles, including 100mm, 105mm, 120mm, and 125mm HEAT, as well as 125mm HE and the spin stabilised 105mm HEP. (Data comes from FT-120-D2, FT 105-A-4, and Stefan Kotsch's website of the ST 50/04/005 125mm and 100mm FTs). The 105, 120mm, and 125mm HEAT (despite its slower start) all drop subsonic somewhere in the 3300 to 3600 m range.The lighter draggier 100mm HEAT is subsonic by 2600 m. The firing tables associated with the later gun systems track the shells out to 5,000 m, which suggests to me that they are still considered militarily useful, despite the subsonic transition. Interestingly, the heavyweight 125mm HE (23 kg projectile, compared with a 19 kg 125mm HEAT projectile or 13.5 kg 120mm HEAT projectile) maintains its supersonic velocity out beyond 5 km. Since a HESH projectile is also heavier than an equivalent HEAT round (18 kg for a British 120mm HESH projectile, vs 13.5 kg 120mm HEAT incl fins, or 11.25 kg 105mm HEP vs 10.3 kg 105mm HEAT including fins), although not as heavy as a thick-walled HE shell, its reasonable to conclude that the velocity curve for a HESH-FS projectile would fall between the HEAT and HE curves for similar fin configurations. If you take the velocity curves for 125mm HE and 125mm HEAT starting from the muzzle velocity of 105mm HEP (which we can take as a known effective speed for warhead function), then we got a velocity graph which shows how the currently existing rounds would perform starting at HESH speeds. If the HESH-FS round was as draggy as HEAT-FS then it wouldn't have any transonic issues until 2,500 m. If the HESH-FS were as good as HE-FS then it wouldn't have any transonic issues until somewhat beyond 4,000 m. Due to the warhead weight and sectional density falling in between the HEAT and HE designs, it would probably have a performance somewhere between the two, which implies no transonic issues until somewhere in the 3,000 to 3,500 m range band. So 'HESH-FS" should be no less effective (in terms of velocity-related dispersion issues) than other full bore rounds out to militarily useful ranges of 2.5 to 3 km. Of course, slow time of flight would still reduce its usefulness against moving targets in the normal fashion, but for dealing with field fortifications and structures it should be just fine.

WOW! A smoke (well, dust) screen with every shot! Yes, even the projectiles in flight are kicking up the dust.

There's nothing in principle that would prevent HESH-FS. HESH/HEP warheads don't require spin to function, and if they were given fins they would be just as accurate as any other fin stabilised full-caliber round (HEAT or HE, for instance) at the same velocity. Years ago we had an American ammunition engineer on Tank-Net (at the time he was working on the M830A1 MPAT and M1028 canister) and he confirmed that there were no show-stoppers about such a configuration.

Very interesting! What are those rounds? They look somewhat similar to the 3BM-46, which has similar aft struts on the sabot, but there are major differences elsewhere (profile of struts, fluted aft ramp, crenellated front edge of mid bourellet, extra front bell, etc.). There's at least two versions here (black obturator and white obturator), and one in the middle even seems to have a translucent sabot petal (or just a change in surface finish causing a weird sheen?). Test rounds of some sort, perhaps from the mid 90s? (1994, if I can make out the numbers on the penetrators?)

Don't forget that the Russian 9K119 Refleks (AT-11 Sniper) tank-gun launched ATGM has an elevated flight path option, to help the missile clear obstructions between the launch and impact points. The missile rises after launch, flies a level flight path at the slightly elevated altitude about 4 to 5 mm above ground, and then descends again shortly before direct impact with the target. So they have already fielded (for decades) the guidance technology needed to make an overflight top-attack missile such as TOW-2B or Bill 2. The fact that they have chosen to keep using direct impact trajectories is a deliberate design choice, not some technical inability.

Ah, that would make sense. Does it strike you that the fuze plugs on the two HE rounds seem to be of different sizes? To me the one on the left of the picture seems larger than the one on the right of the picture. Optical illusion or reality? It also seems like the other guy with a charge may also be holding the fuze in his left hand, base towards us, and it is definitely smaller than the one stacked on the charge. Two different HE rounds, one with a fancy multipurpose fuze?

What's the conical-tipped projection coming from the top of the propelling charge? Or is it just something else he's carrying on top of the charge, or something on his uniform that happens to be in that spot coincidentally?

Bear in mind that the tandem dart sabot round there (labelled #6) is a concept drawing taken from western patent literature, rather than an actual round.

I have seen TV footage of Merkava 11 Dor Dalets still equipped with "R2D2s" during the current conflict Here are two pictures of "R2D2"s on Merkvas, that were posted during the last couple of weeks. I've been keeping an eye out for them, but there certainly haven't been as many as last time.

Are those impact marks on the two plates on the rear of the turret?? The one on the right is petalled out in a way that almost looks like a full caliber AP hit.

Well, we'll see, but I think that's very optimistic based on the constant stream of crashes this thing has been generating for me. Up to this point I've been getting several a night with big scenarios, and I don't think they've made a lot of changes from B501 to the 1.03 release.

So was I, when I bought it last week. Now I'm not so sure... While it has potential, be aware that despite the steep price you're getting a very unpolished product. They do look like they have good continuous developer support, and if they continue to make improvements it may reach its true capability, but at the moment I find it has a lot of little bugs and flaws that really detract from my appreciation of it. If I had a chance to try a demo in advance I would probably not have paid this price for it. That being said, I'm off to try bombing Khark Island again, so please excuse me for rushing off.

Years ago we had a contributor on the Tanker's Forum who worked in ammunition development for the US. He indicated that one of the main reasons the US went with the 'shotgun' style canister round was the desire to avoid the time fuze associated with most APERS rounds. Developing and qualifying a new fuze is apparently a very expensive and time consuming process, with lots of bureaucratic safety-related hurdles. Since simplicity and cost were the driving factors in developing the XM1028, they opted to take the simplest path they could.

Wow, they really have a little bit of everything there... AP, HEAT, HE (2 types), APDS, and APFSDS. I'm surprised there's so much full-bore AP (BR-412B, I think) in the mix. Is this a case of "they'll take anything they can get", or are they specifically looking for it as a means of dealing with very heavily walled positions? The long HE rounds do look like an AA round. In some issues of Jane's Ammunition Handbook there is a picture of an Egyptian 100mm AA HE round with a very similar shape, including the two broad bands on the rear half of the shell, the long profile, and a large fuze. I think the fuze on the ones in the video is probably mechanical time under a protective cover (you can see the cover is dented in some of the close-up shots), rather than being proximity fuzed with a dark radome. [Edit: Wiedzmin just posted a picture of such a mechanical time fuze with cover on the Main Gun Ammo - Revisited thread, post 473, where it is mounted on a flechette round.]

NHS refers to the NATO Heavy Single target, which is one of several types of standardized test targets defined in STANAG 4089. As I recall it is a single 150mm plate at 60 degrees.

I have to admit I'm also puzzled by that extra little 'sensor aperture' , if that is indeed what it really is. If this is a SALH guidance package, why would it need an extra little sensor aperture at all? Couldn't the large optics in the main window handle the detection and tracking of the laser spot, without needing to add something new? Other SALH missiles such as Maverick and Hellfire, and I believe LAHAT and Nimrod also, use the sort of gimballed optics you can see in the main nose window, without any extra sensor windows. It would be reasonable to assume that the large optics could play the same role here on the Machtselet / Spike NLOS. So if this is a SALH weapon (and that seems reasonable), and the main optics handle the laser tracking, then that still leaves the function of the little aperture unknown. It looks like we can see into it, which suggests it is an optical sensor, rather than an electronic sensor, because they would presumably put an electronic sensor under an opaque dielectric cover, rather than adding the complication of an unneeded optical window. It looks like it has a fixed field of view, and it's very small, so it's probably not an imager that gives great detail. Perhaps it's some sort of filtered wide-area sensor to help the missile differentiate between the coded laser spot and other spurious signals? The guidance computer would compare an image frame when the little sensor says the laser is on, and the adjacent frame when the little sensor says the laser is off, and subtract the two, leaving only the position of the laser spot. (Could the main optics simultaneously handle the laser spot and an image? I believe many modern CCDs are sensitive into the near IR, so in principle, yes?) Alternatively, perhaps it's a basic cueing sensor, to let ground troops use a simple laser to point out that "the target's somewhere over here", after which the operator could use the conventional imaging function to do the final homing. Any other options? Edit: Perhaps an IFF beacon sensor, to pick up IR strobes on friendly troops, and put a big X on the operator's screen if the missile's heading towards a friendly target? Edit 2: I can't wait to find out that there's actually a flat transparent plastic weather cover on the front of the missile tube, and the "sensor" is a sticker on the window saying "Inspected by # 12"...

Is that an additional sensor aperture on the new generation missile?

Aha! I should have remembered to to check that thread. Thanks for the reminder. It's interesting that the helicopter in your picture has the bulkier active laser jammer over the engine, while all the ones in the pictures I found have the more conventional 'hot brick / disco ball' style jammers. How long have the laser jammers been in service now? Are they planning to phase them in across the fleet?

Thanks for the links Chris. The more I look at that chin object, the more and more I think that it's an antenna of some sort, such as a horn antenna with a curved waveguide at the back and a dielectric cover on the front. Here's some assorted horn antennae, rotated to match the orientation seen in the photo above, and the general shape is a pretty good match (well, to my eyes anyway ). We know that the SPIKE NLOS system uses a fairly large directional antenna to communicate with the missile. If Machtselet is a member of the SPIKE NLOS family, then presumably it needs some sort of directional data link antenna too. A pointable chin antenna might do the trick.

I was looking at the Israeli Military Photos topic on MilitaryPhotos.net, and came across some pictures of Israeli Cobra helicopters with a weapons fit I do not recognize. http://www.militaryphotos.net/forums/showthread.php?58508-Israel-Defense-Forces-%28Read-First-Post!%29/page1059 Instead of the usual gatling gun under the chin, the helicopter has a wedge shaped object in that position, and instead of the typical large ATGM tubes it has a smaller hardpoint of some sort. It looks like the wedge shaped object is some sort of trainable directional antenna. Interestingly, the unit seems to be organized with a roughly 50 / 50 mix of these helicopters and those with the normal gatling and ATGM fit. Here's another picture showing a Cobra with no chin gun, but no antenna either, although it does have the small hardpoint. A little more googling turned up a picture of a Cobra carrying the antenna as well as what look like missile boxes on the hardpoint. So what is this system? I don't think this would be Spike ER, which brochures show to be tube launched and fibre optically guided, so the helicopter can retain its gun. My guess would be Spike NLOS / Tamuz, which is a box launched long range missile that uses a radio guidance link. If so, wow. A 25 km range missile on a highly mobile and elusive helicopter platform. Good luck defending against that... My weak google-fu hasn't turned up a name for this combination. Is there a new model name / number for the Cobras carrying this weapons fit?

We always light the mortars that way. It stops you from burning your hand on the fuze. We have a big home fireworks show every year, with three people lighting simultaneously, and we also use propane torches. The auto-ignite types are ideal, giving a strong instant flame for rapid ignition, with no fiddling about with lighters etc., and have enough power to light the fireworks rapidly even if the fuze is not ideal. The moment you let go the flame is out, so you don't have an active ignition source between shots, and you don't have an additional bright light to distract the audience from the real show.

What is the function of the turret screens?

Well, actually they only say Caine and Theron were in negotiations back in 2001. They didn't actually go ahead and act in the movie. (He probably just phoned their agents...) The final cast is somewhat less impressive. http://www.imdb.com/title/tt2507628/?ref_=fn_al_tt_1 There also seems to have been an earlier version of this by the same director, with truly dreadful reviews. http://www.imdb.com/title/tt0425638/

So something like this instead? That would probably be mechanically simpler (smaller lighter elevating structure) than a central launcher, although it would be more vulnerable to damage, being on the outside. The main thing would be that they now only have two shots before they have to get out and wrestle a fairly hefty set of missiles out of the central storage space, and over and into the box launcher. (Unless they've somehow built a lateral autoloader into the system, which seems like a lot of complication and expense.) Having all twelve missiles ready for immediate use would be a lot more operationally responsive. Edit: Alternatively, if the left sponson is tall enough, and there is nothing in front of it to get in the way, you could have a set of fixed missile rails already at the proper elevation inside the sponson, eliminating the need for elevating mechanisms. It doesn't look like there's enough room for that though.

I agree. I think the tank with its rear hatch folded down is showing a completely empty magazine. You can see the mounting rails for four sets of three missiles, but there are currently no missiles in it, so it's mostly just a large cavity. The other tank (the one I made the sketch on) has its rear hatch shut, so you just see the blank flat plate at the back of the bustle.