Proper CBU-97 employment

[Galwran]

Hi,

I used to know how to use the CBU-97 efficiently, but have somehow forgot everything. Could you brief me how to solve a basic scenario?

 

Lets says that you are carrying 2xcbu-97s. You spot a column of 4 tanks in a V formation. Tanks are driving approximately 20km/h and have no AAA/SAM support, so I can choose the attack vector and altitude freely.

 

What to do next? What to set as the HOF, where to aim when using CCIP? If I have the time, should I use the CCRP mode and Litening? What if the tanks are stationary, where to aim?

 

Of course I manage to get a few hits, but I'm certain that it is just pure luck & waste of ammo. IMHO 2x CBU97s for four tanks is often overkill.

[Belisarius]

I'm nobody to instruct anybody BUT had some great success and great fun this morning using cbu 105's in the "surrounded " mission. After many months using labels to make things easy I'm finally done with them. I like this mission because it's easy to judge n, s, e and west calls from jtac....helping to gain a whole new degree of situational awareness and using zoom to spot targets with mark ii eyeballs. Anyhow I would find the moving column, simply guess by their speed and my distance how far ahead on road to place spi and dropped with ccrp..managed a good hit on convoy after convoy....GreatFun and fireworks! Still sometimes have to cheat with active pause..but I'm getting better! Also adjusted HOF to 900 feet to restrict hits to road area and decrease waiting time for the show! Love this sim!

[Scrim]

There's no good, single answer to this. Is there wind to take into account? The CBU-97 and -105 bomblets are parachute suspended, and thus extremely liable to being blown off course by even light winds, especially if they deploy from higher altitudes. That's all about training, trial and error, etc. Eventually you'll have it pretty well figured out. Trying to hit moving targets with something as erratic as -97 and -105 bomblets in a sense are is not easy. The more you do it against easier targets, the closer you'll come to learning how to do it against moving targets.

 

HOF is obvious. The higher they deploy, the greater the spread. Since this is a very wide area weapon, as long as you can control where the spread goes, the greater the spread the better, as this ensures that multiple targets are hit. But as mentioned, the greater the HOF, the longer it'll take for the bomblets to go off.

 

IMO, use CCRP, especially if you have a TGP. It allows you to fly a more stable path, and in my experience, CBUs tend to misjudge their altitude to a certain degree when dropped with CCIP. And as previously mentioned, due to the wide area effect, the pinpoint accuracy that CCIP can give you over CCRP is uncalled for.

[112th_Rossi]

If I have to hit a moving target, I tend to try and disable the lead element first with a maverick. The convoy backs up and I destroy the rest with a CBU, if it's safe to do so.

[Boris]

Just how effective are CBU-97s meant to be against tanks? I just tried bombing a column of 10 T-72s. I ripples 6 CBU-97s onto the column, just to see how many I could get. From the external view I could see that the spread was pretty good over the column.

 

I killed 6 out of 10. Good ratio with 6 CBUs???

[Flagrum]

Just how effective are CBU-97s meant to be against tanks? I just tried bombing a column of 10 T-72s. I ripples 6 CBU-97s onto the column, just to see how many I could get. From the external view I could see that the spread was pretty good over the column.

 

I killed 6 out of 10. Good ratio with 6 CBUs???

I would say, that is pretty decent - especially considering that CBU-97 in DCS are considered somewhat "broken" in terms of effectivity. A CBU-97 contains 10 sub-munitions container with 4 skeets each. So theoretically one CBU is worth 40 kills. But not every skeet finds a target and also often several skeets fire at the same target. But there were reports here on the forums that someone dropped 2 CBUs on a moving column of 4 only to get 1-2 kills.

I don't know how effective this weapon is in RL, in DCS the results seem to vary quite a bit.

 

What HOF did you use?

 

edit:

LOL, scratch the beginning of the first sentence ... I overread that you dropped 6 CBUs! 6/10 kills with SIX CBU-97? No, even for "broken" DCS CBUs is that an inacceptable ratio. Therefore once more: what HOF did you use?

Edited May 8, 2014 by Flagrum

[Scrim]

Not bad considering the circumstances. Thing is that when they're so bunched up, the bomblets tend to center on the same targets. Had they been more spread out, in perhaps a wedge, I reckon there'd have been more hits.

 

That, and I can't quite recall, but I think the number of bomblets for CBU-97s and -105s are less than IRL due to performance. The -87s and -103s definitely are, but I can't remember for sure if it was just those that got less bomblets than IRL.

 

Also, due to the size and less than ideal aiming of the bomblets, you can't expect one kill for every single one. Some are doomed to malfunction in various ways, and a bunch of them will trigger at parts of the target that aren't the least vulnerable, like equipment strapped to the tank, turret mounted MGs and optics, tracks and wheels, armour at lousy angels, etc.

Edited May 8, 2014 by Scrim

[NoJoe]

6 kills in a single pass is pretty darn good! Consider how long it would take to do the same thing with the gun, or Mk-82s. Also consider some of the "not-killed" tanks may still have been damaged and degraded to some extent.

[Flagrum]

Not bad considering the circumstances. Thing is that when they're so bunched up, the bomblets tend to center on the same targets. Had they been more spread out, in perhaps a wedge, I reckon there'd have been more hits.

But still ... I mean, SIX CBUs ...!?

 

That, and I can't quite recall, but I think the number of bomblets for CBU-97s and -105s are less than IRL due to performance. The -87s and -103s definitely are, but I can't remember for sure if it was just those that got less bomblets than IRL.

The graphical effects are reduced - especially for the 87, but the performance should not been altered by that change - that is at least how I understood it.

 

Also, due to the size and less than ideal aiming of the bomblets, you can't expect one kill for every single one. Some are doomed to malfunction in various ways, and a bunch of them will trigger at parts of the target that aren't the least vulnerable, like equipment strapped to the tank, turret mounted MGs and optics, tracks and wheels, armour at lousy angels, etc.

my remarks in blue

[159th_Viper]

Just how effective are CBU-97s meant to be against tanks? I just tried bombing a column of 10 T-72s. I ripples 6 CBU-97s onto the column, just to see how many I could get. From the external view I could see that the spread was pretty good over the column.

 

I killed 6 out of 10. Good ratio with 6 CBUs???

 

What was your Ripple Interval set at? Ensure it's set to adequately cover the convoy length.

[Scrim]

Flagrum: Well, depends on. How close where the CBUs dropped to each other for example? If they were too close to each other, they might've just overkilled a few tanks. And the other way around, some might've ended up being dropped too far away from the tanks. Hard to say, but I'll give it a go. Also, -97s are unguided; Some might've missed the column completely.

 

More than the graphical effects must've been decreased. A real life CBU-87 has 202 bomblets. Now, I've not counted the number of explosions from dropping one in DCS, but there is no way it was even 100.

Edited May 8, 2014 by Scrim

[Flagrum]

Flagrum: Well, depends on. How close where the CBUs dropped to each other for example? If they were too close to each other, they might've just overkilled a few tanks. And the other way around, some might've ended up being dropped too far away from the tanks. Hard to say, but I'll give it a go. Also, -97s are unguided; Some might've missed the column completely.

 

More than the graphical effects must've been decreased. A real life CBU-87 has 202 bomblets. Now, I've not counted the number of explosions from dropping one in DCS, but there is no way it was even 100.

Of course is it possible and explainable to kill, well, only 6 tanks with 6 CBUs. But the question was if that is a decent ratio. And even considering the inherent shortcomings of that weapon system, it should easily be possible to kill all 10 tanks with much less CBUs (my guess would be like 3-4 ... 2 in an ideal world ...). Or the other way around, 2 CBUs should be enough to archieve a 6/10 kill ratio. (ok, I am guesstimating, but still ...)

 

The number of visible explosions was reduced for the 87, yes, but somewhere (Wags? Change logs?) it was stated that this would not have an impact on its destruction potential.

Edited May 8, 2014 by Flagrum

[Scrim]

Just tried it. 10 T-80s in a column, stationary. 6 CBU-97s near perfectly dispersed over the entire column, front to rear. HOF 3000 feet with no wind, to ensure it was the CBU-97s that I was testing, not my own skills.

 

The result was 8/10 tanks totally killed, with medium damage to 1/10, and 1/10 that got away with no damage. I feel that's very good for an unguided weapon. I'll tamper around a bit more. If the spacings are increased to overstretch the length of the column, that might result in a better spread, and thus a higher CBU/kill ratio. And regardless of the HOF, they will still wait until they get down to a very low altitude before they start hitting the targets. This makes possible the problem to some tanks being blocked by others.

Edited May 8, 2014 by Scrim

[txmtb]

I was trying to find an old thread but can't remember what it was or who posted it.

They had made a TE with square columns of 10 x 10 or 15 x 15 non-moving tanks and dropped different ordinance to see the effect.

A single CBU only achieved 2 kills IIRC.

[Flagrum]

Just tried it. 10 T-80s in a column, stationary. 6 CBU-97s near perfectly dispersed over the entire column, front to rear. HOF 3000 feet with no wind, to ensure it was the CBU-97s that I was testing, not my own skills.

 

The result was 8/10 tanks totally killed, with medium damage to 1/10, and 1/10 that got away with no damage. I feel that's very good for an unguided weapon. I'll tamper around a bit more. If the spacings are increased to overstretch the length of the column, that might result in a better spread, and thus a higher CBU/kill ratio. And regardless of the HOF, they will still wait until they get down to a very low altitude before they start hitting the targets. This makes possible the problem to some tanks being blocked by others.

I think, the spread increases with altitude, even without wind. Try 3 along the colum as ripple single with HOF 700 or 900.

[Eddie]

The CBU-97/105 should deploy the BLU-108s in such a way that they cover a 800 ft wide x 1600 ft long pattern (the chutes on each BLU should open sequentially on ensure even spread). HOF does not, and should not be a consideration for the SFW, the submunition spread is all pre programmed, or should be. HOF only affects the point at which the CBU canister opens, it has no impact on the chute deployment or skeet dispersal.

 

A single 97/105 should be quite capable of taking out 6 MBTs, subject them being inside the design footprint of course.

 

At present in DCS the CBU-97/105 is generally about as effective against light/heavy armour as the CBU-87/103 should be. And the CBU-87/103 is significantly less effective than in should be vs light armour, and even soft skinned targets.

 

So to directly answer the question, no 6 MBTs with 6 SFWs is not even close to a decent ratio, it's downright pitiful.

[Boris]

I would say, that is pretty decent - especially considering that CBU-97 in DCS are considered somewhat "broken" in terms of effectivity. A CBU-97 contains 10 sub-munitions container with 4 skeets each. So theoretically one CBU is worth 40 kills. But not every skeet finds a target and also often several skeets fire at the same target. But there were reports here on the forums that someone dropped 2 CBUs on a moving column of 4 only to get 1-2 kills.

I don't know how effective this weapon is in RL, in DCS the results seem to vary quite a bit.

 

What HOF did you use?

 

edit:

LOL, scratch the beginning of the first sentence ... I overread that you dropped 6 CBUs! 6/10 kills with SIX CBU-97? No, even for "broken" DCS CBUs is that an inacceptable ratio. Therefore once more: what HOF did you use?

 

I used the default of 1800. You think it might help of it's lower?

 

1 CBU per tank is not a very good ratio I think. I can get that with 6 GBU-12s or 6 Mavericks with a much higher chance of success.

 

I've been doing a few more runs, and I still can't get above the one CBU per tank ratio. ie. I drop 3, I kill 2 - 3 tanks, I drop four, 3 - 4 tanks etc.

 

EDIT: I just killed 5 tanks with a ripple of 6 Mk-82s ... And I can carry 3 of those per hardpoint. I fail to see the point of the CBU-97 at this stage. It's a shame, because it seems like a really cool weapon.

Edited May 8, 2014 by Boris

[Flagrum]

The CBU-97/105 should deploy the BLU-108s in such a way that they cover a 800 ft wide x 1600 ft long pattern (the chutes on each BLU should open sequentially on ensure even spread). HOF does not, and should not be a consideration for the SFW, the submunition spread is all pre programmed, or should be. HOF only affects the point at which the CBU canister opens, it has no impact on the chute deployment or skeet dispersal.

 

A single 97/105 should be quite capable of taking out 6 MBTs, subject them being inside the design footprint of course.

 

At present in DCS the CBU-97/105 is generally about as effective against light/heavy armour as the CBU-87/103 should be. And the CBU-87/103 is significantly less effective than in should be vs light armour, and even soft skinned targets.

 

So to directly answer the question, no 6 MBTs with 6 SFWs is not even close to a decent ratio, it's downright pitiful.

Regarding spread of the BLU-108 ... I was under the impression that the chutes cause the spreading because of the turbulences and uneven airflow they cause. If that is true in RL and/or if or how pronounced this effect is in DCS ... hrm. Now after some testing, it seems that the spread is more or less negligible - the BLU-108 come down in a relatively dense "cloud", no matter of the HOF. (seems that the density here is one of the issues with the 97 ...)

[Mike5560]

I find that the footprint of the submunitions always fall short of my SPI. If I place 3 T-80s in a triangle formation, but default spacing per the editor. I can kill at least two, usually all 3 tanks with one 105.

 

I drop at 5,000 ft, funtioned at 1800 ft. I start my TGP crosshairs at center or the three tanks, then I slew the cursor about 40-50m downrange (since the submunitions fall a little short) and set as SPI. This is in zero wind, however.

[Scrim]

The greater the HOF, the greater the spread. It's just common physics. That's real life, and DCS.

[ShuRugal]

I find that the footprint of the submunitions always fall short of my SPI. If I place 3 T-80s in a triangle formation, but default spacing per the editor. I can kill at least two, usually all 3 tanks with one 105.

 

I drop at 5,000 ft, funtioned at 1800 ft. I start my TGP crosshairs at center or the three tanks, then I slew the cursor about 40-50m downrange (since the submunitions fall a little short) and set as SPI. This is in zero wind, however.

 

This is because the 'puters in the A-10C calculates the release/impact point based purely on the ballistic trajectory of the round. It doesn't account for the fact that, at 1800 ft AGL, the weapon is suddenly going to be slowed by a chute.

 

Whether this is true-to-life behaviour I've no idea, but the practical upshot is, if you want your spread perfectly centered, learn to kentucky windage your point of aim.

[Boris]

learn to kentucky windage your point of aim.

 

Thanks, I just learned a new term :thumbup:

[ALDEGA]

learn to kentucky windage your point of aim.

I wish they could teach the AI ...