Some Giro thoughts
 

I am wondering if modern Russian stuff is possibly to good cant find info on perhaps Epoletov could chip in think he did work on recent Russian OOB changes.

With out checking to my knowledge West has the following tanks with 6 stabilization.
USA - M1A2 SEP
Australia - There Abrams & only none USA version, error?
S. Korea - K1A1
Israel - Merkerva Mk4

Russia T-80 UM (not Bars)
T-90A

Both have stabilisers rated 6 which for the following reasons I find suspect.
T-80 I think has the bigger turret ( if remember correctly) though still small by Western standards so if any has 6 would expect it to be T-80.
How did they keep pace with USA tech looking at military budgets over the last few years, in game Russia gets 6 giro 2 years before USA does.
Also Russian refit/new tank production has been fairly limited AFAIK so giving the majority 5 makes sense to me or even 4 like the export T-90s are given.

Also related Ukraine T80 UD has giro of 4 & never improves, also the T-84 has a giro of 3. Pretty sure Ukraine said they made improvements possibly not to giro but to overall FC.

In summary I think T-90A is nearly on par with SEP & Merk4 in game terms with fractionaly less FC while T-80 UM matches most Western tanks on FC but has a better giro.
In game terms & not advocating changes due to this just pointing out modern Russian stuff is probably modeled as being more capable of hitting Western armour than the reverse as they are 1 size smaller. Certainly if fire involves moving a short distance to engage.

Re: Some Giro thoughts
 

"Epoletov" had nothing to do with the lastest OOB changes beyond the occasional comment on the forums that was investigated just as yours are and I really wish you would spend at least 1 minute checking what you write as "Australia - There Abrams & only none USA version, error?" makes NO sense whatsoever. I cut non english speakers some slack but that's not the case here

Don

Re: Some Giro thoughts
 

Was just going from memory
Aus unit 26 M1A1 AIM SA has 6 giro so possibly an error?
There may be other 6 giro units out there but these are all I know of as tend to look at when I buy to gauge capabilities.

Re: Some Giro thoughts
 

I have been very surprised and at that time flattered by attributing to me of such merits.
It is a pity, but it not so. :)

Re: Some Giro thoughts
 

The Australian Abrams have had a full upgrade

Don

Re: Some Giro thoughts
 

There is no positive correlation between turret size and stabilization performance; actually in principle a bigger, heavier turret should mean more momentum the servos would have to struggle against during a change of course.
AFAIK the most common modern configuration is that the sights are independently stabilized, since a piece of glass is light it is relatively easy to do, while the gun/turret stab working as they are against tons of mass try to keep up as well as they can. The computer accounts for the difference and actually witholds fire until the gun is properly aligned.

This may be true in but only a "big picture" perspective. In practice the USA is not the world leader in every single category of military item and subsystem out there. There are areas, such as tube artillery and antiship missiles to make a couple of well known examples, where the US is either lagging behind or just barely keeping up. This happens because there are other factors which compensate for that (say, airpower) or they are not felt to be as important as something else because of doctrine or whatever.
The US was developing a world class self propelled artillery piece with the Crusader, but it was decided to terminate it in the attempt to develop something with better strategic mobility even if with lower performance. That did not work so the US Army is stuck with M109s, a early 60's design however upgraded it has been.
All along huge budgets were allocated, vast sums were spent and no actual hardware was ever issued.
Bottom line, it is perfectly plusible that the russians might have deployed a marginally better stabilizer system a bit earlier than the US (we aren't talking huge differences here) even if they can fling less money around, simply because they focused on it.
I vaguely recall to have read about T-90 stabilization parameters somewhere, but whether the data was accurate and similar data is available for late marks M1A2, God only knows I suspect.

Re: Some Giro thoughts
 

I have done some digging and found the following.

Leclerc
Source 1
medium error of stabilization: 0,1 mrad vertical - 0,1 mrad horizontal

Source 2
medium error of stabilization 0,15/0,20 mrad vertical - 0,3/0,4 mrad horizontal

Leopard 2A4
medium error of stabilization: 0,15/0,20 mrad vertical - 0,3/0,4 mrad horizontal

M1A1
medium error of stabilization: 0,15/0,20 mrad vertical - 0,3/0,4 mrad horizontal

T-90 (not specified which variant)
medium error of stabilization: 0,4 mrad vertical - 0,6 mrad horizontal

Pinch of salt applies.

Re: Some Giro thoughts
 

May I ask for sources? Also do they mantion older generation as well?

Re: Some Giro thoughts
 

Hi Marcello was generalising with comment about military spending certainly bang for the buck think most countries do better than USA when it comes to R&D & sure Soviets have the edge or at least a diffrent way of doing things in some areas.
Giros might be one as despite I think inventing US lagged behind for a long time & Soviets placed emphasis on mobility. Still refiting/upgrading is I think questionable hence my comment perhaps majority should have 5 or even 4 but all speculation on my part as found no data. Mentioned as a lot of work went into Russian OOB a while back & its so easy to enter something wrong. For instance from memory T-80 UM Bars started as the upgraded version in present times its now the underdog to standard T-80 in game terms. This may be right without doing research but think Russia only produces a handfull of T-80s a year if sources are to be believed.

Re: Some Giro thoughts
 

Various Tanknet posters. Next week I will try to check if I can find the original sources, say sales brochures or whatever.

That was common. A lot of western tanks of the 50's and 60's lacked stabilization as it was felt that stabilizers of that vintage were only partially useful. On the other hand most of them had optical rangefinders which the soviets lacked until early T-64s and T-72s.

I am not saying that's wrong, in fact it is likely to be the case. I am saying that inferring such things from the "big picture" is, for a country like Russia, a tricky proposition. They can be quite good at engineering if they put themselves at it.

AFAIK T-80 production has been terminated. T-80s will be kept around and upgraded, but no new production.

Re: Some Giro thoughts
 

'On the other hand most of them had optical rangefinders which the soviets lacked until early T-64s and T-72s'

My understanding is stadiometric optical rangefinders till 74, then laser after that. T-55A gets 'Newa' TKI laser rangefinder in 74.

Re: Some Giro thoughts
 

Naturally stadia lines were used for ranging with the sights, but this is not comparable to a full blown coincidence/stereoscopic rangefinder as employed on the early
T-64/T-72 and 60's western MBTs.
With stadia lines you are essentially guessing range on the basis of the apparent size of the target: if it looks big it means it is close, if small it's far. One problem is, the stadia marks used for measuring have to be calculated and drawn for a predetermined target; if the target differs from that, because of profile, actual size etc. accuracy is off. This is not an issue with the latter types.
Now, how much this is an issue in real life battles I don't know, but adding a relatively maintenance intensive piece of kit must have been felt to be an advantage, at least for the type engagements planned (same applies to stabilizers on russian
T-XX).
It has been reported that there was an istance of iraqi T-55s engaging USMC AMTRACs and missing with all shots falling short. Supposedly because they were bigger than the standard size target, so they appeared closer than actually were and therefore insufficient superelevation was applied. But such stories have to be taken with pinch of salt.

Re: Some Giro thoughts
 

Marcello, yes of course stadiometric range-finding is pretty inferior to coincidence, the method is really a multiple round one, the first shot determines the error which is then corrected, hence the almost universal use of use of AP-T rounds on the D-10T, the tracer allowing easier spotting of range error. A skilled gunner could of course estimate the ratio of the size of the target against the target the Stadia was designed for, and make some first round correction.

When did Russian tanks get coincidence rangefinders, and on what models ? My understanding was there was a transition straight from stadiametric sights to the TK-1 system.

For example, the T-62 has stadiometric rangefinding with TSh-2B-41 gunner day sight (3.5/7x)and TPN1–41–11 night sight from 1960 till 75, where it then gets the TK-1 or TK-3 laser system.

Was there a coincidence system installed between 1960 and 75 ? I cannot see any mention of it ?

Re: Some Giro thoughts
 

No USSR units that I know of used optical rangefinders - they went straight from stadia to LRF in the 70s on later model T-72 and 64 etc.


Andy

Re: Some Giro thoughts
 

Thanks Andy that was my understanding.

I have one more question, how long did it take to range and aim with the Volna FCS, what was automatically entered and what was manual ?

My understanding is turret traverse speed is entered automatically from sensor in the turret ring, but round type, temperature, and range manually entered, with range determined from TK-1 laser rangefinder.

Once the solution was found, did the chevron (dot) on the scope automatically move, or was there simply some increments (for lead and super-elevation) that had to be matched manually to the solution produced by the computer ?

Re: Some Giro thoughts
 

I have to disagree. Early T-72s were fitted with the TPD-2-49 coincidence rangefinder.

http://a.imageshack.us/img201/8716/t72081b.jpg
http://a.imageshack.us/img201/7532/t...stiles1nv4.jpg

Notice the rangefinder ports on the turret roof near the sides. Early T-64s had a similar arrangement.
Naturally T-55/62 went straight to lase but as I said early production T-72/64 relied on optical units.

Re: Some Giro thoughts
 

Marcello is of course correct, optical rangefinders were installed in the first T-64 A modernization in 69/1970, apparently lasers were not fitted till 81.

Re: Some Giro thoughts
 

Hmm - you do learn something new, from time to time!

(And it looks as though these are already factored in the OOBs from a look at the R/F values)

Andy

Re: Some Giro thoughts
 

I would pity the poor crews trying to shoot in the dark with nothing but stadia in the night sight on a late 70's battlefield though !

Marcello, TPD-2-49 is listed as a day sight, so is the rangefinder and sight the same unit, or is it two pieces of equipment, with the operator ranging with the rangefinder, then(manually) matching the range to a superelevation mark on the gunsight, as in a non automated laser system ?

Re: Some Giro thoughts
 

It is an integrated unit. You range and aim looking in the same sight. There is a video of the operation available at this page
http://www.t-72.de/html/tpd-2-49.html

Max vision range on the most common export (something better was available but not widely used outside USSR) T-72 night sight supposedly was 600-800 meters, with one km achievable only under optimal conditions. At those ranges you could fire APFSDS without worrying too much about ranging and superelevation.

Re: Some Giro thoughts
 

Thanks that is a brilliant video,

I take your point about the night sighting at <800 meters, at 1750 m/s there is not going to be that much super-elevation ! According to the page you quote it is about 50cm at max night target acquisition range.

Also there is no stadia on the night sight at all.

http://www.t-72.de/html/tpn-1-49-23.html