CBU-105 weapon of choice for tank groups

[flavnet]

Hello everyone! Whatever weaponry you have tried for the A-10, forget it! 4 CBU-105 are enough to destroy a (stationary) column of 30 tanks and 20 APCs!!!! This bomb is devastating!! Within the range of the bomb, it's possible to drop the 4 bombs by targeting (quickly) 4 targets of the column (a pair nearly at the ends and a pair towards the center), so that the bombs are fired at approximately the same time. The show is guaranteed (as long as you have a good graphics card).

[SPAS79]

also the 97, at a a slightly lesser weight. 

[flavnet]

The 97 is a little more risky to use. The 105 is really comfortable. I use it from 28k feet and it's like God suddenly fell on enemies (and I mean all enemies).

[Yurgon]

You better hope there are no friendlies within what? Half a mile?

 

What I'm trying to say is: Use the right weapon for the job. Column of tanks? CBU-97 and CBU-105 will come very handy. Pick a single target in an urban environment with friendlies in close combat, CBUs (no matter which one) probably aren't the weapon of choice.

[jaylw314]

6 hours ago, flavnet said:

The 97 is a little more risky to use. The 105 is really comfortable. I use it from 28k feet and it's like God suddenly fell on enemies (and I mean all enemies).

 

The CBU 97 has the advantage of being able to pair/ripple drop them for maximum CPU-melting chaos

 

[LeCuvier]

I've used the CBU-105 a lot in the past and I could rarely kill more than 3 armoured vehicles with one bomb. Recently I used it again and it killed almost everything within range. It has obviously been made more deadly. I hope it will stay that way!

[flavnet]

On 8/21/2021 at 7:14 PM, Yurgon said:

You better hope there are no friendlies within what? Half a mile?

 

What I'm trying to say is: Use the right weapon for the job. Column of tanks? CBU-97 and CBU-105 will come very handy. Pick a single target in an urban environment with friendlies in close combat, CBUs (no matter which one) probably aren't the weapon of choice.

Absolutely true. In reality, I think it has rarely been used by US forces. Instead, it seems to have been used very freely by Saudi Arabia in the war in Yemen. In fact, as you have noticed, it is a weapon that should be used very carefully considering the side effects. But I think the Arabs don't have much scruples. In a video game you can enjoy the effect on enemies without regret.

[QuiGon]

On 8/22/2021 at 12:47 AM, LeCuvier said:

I've used the CBU-105 a lot in the past and I could rarely kill more than 3 armoured vehicles with one bomb. Recently I used it again and it killed almost everything within range. It has obviously been made more deadly. I hope it will stay that way!

 

I use the CBU-97/105 for 10 years now and it has always been extremely deadly to groups of vehicles!

[rapid]

My personal favourite is the 97....i'll give the 105 a try must have over looked it.

Edited August 23, 2021 by rapid

[escaner]

CBU-97 and -105 are basically the same bomb, just the -105 is wind corrected but it cannot be used in CCIP mode.

[Captain Orso]

Be aware though that currently the WCMDs do not correct for wind correctly; they only correct for the fall of the canister. They however do not take into account the drift of the submunitions on parachutes after being ejected from the canister. A good breeze can blow all of the 10 BLU-108 sticks so far off target that not a single skeet will find an intended target.

[ZeroReady]

After years of using both 97 and 105 I still don't really understand the advantage of the WCMD. I understand it uses a spi to CCRP drop to precise location via INS magic. Or something. But doesn't the CCIP sight use LASTE info to predict where a bomb would impact, also taking wind into account? 

 

If CCIP drops didn't take wind into account, wouldn't it be kind of useless? I can CCIP a Mk82 into the window of a truck from 15,000 feet.

 

Does the 105 dispenser actually have guidance like a JDAM? Is it supposed to account for the parachutes blowing in the wind and burst at the right spot to negate the wind?

[Yurgon]

1 hour ago, ZeroReady said:

But doesn't the CCIP sight use LASTE info to predict where a bomb would impact, also taking wind into account? 

 

All release cues take wind into account. Normally, this would be the wind that the aircraft measured during its flight thus far, but wind data can also be manually entered via the CDU.

 

CCIP or CCRP don't make a difference in that regard; all these cues/pippers/aiming helpers account for wind.

 

 

1 hour ago, ZeroReady said:

Does the 105 dispenser actually have guidance like a JDAM?

 

As far as I'm aware, JDAMs actually feature a GPS receiver and use GPS-aided targeting.

 

CBU-103 and CBU-105 are inertially aided munitions (IAM) using an inertial navigation system; they don't have GPS guidance.

 

The whole point of IAMs is that they account for wind all the way to the target. Imagine a day with rather variable weather conditions and an A-10 with a 200 mile ingress; how could its systems know the exact wind data for all the layers between the drop altitude and the target, that far from where the aircraft initially climbed up to altitude?

 

In DCS, when using static weather, the wind is uniform across the entire map, and so the A-10C's wind data will be correct for every corner of our playground, which is why CCIP as well as CCRP (when used by a decent pilot) will be spot-on.

 

With dynamic weather, what we should see is a rather significant degradation of the aircraft's wind prediction, once the jet enters a region affected by a different weather system. But whether or not that's modelled, I must admit I don't know.

 

 

1 hour ago, ZeroReady said:

Is it supposed to account for the parachutes blowing in the wind and burst at the right spot to negate the wind?

 

I believe it is supposed to do that, but in DCS it doesn't.

Edited August 26, 2021 by Yurgon

[Captain Orso]

CCIP is very old - like Vietnam War era old - and a fairly simple calculation - you don't need supercomputers to do it, it's slide ruler stuff.

 

I'm not actually sure tha CCIP takes wind into account. IIRC in the Harrier NATOPS they talk about compensating for windage with CCIP. 

 

CCIP only measures the fall of the dumb bomb corpus. If you are dropping canisters which don't then deploy submunitions on parachutes, then the effects of wind on the ejected submunition is fairly minimal. On submunitions on parachutes, it's enormous.

 

IMHO the only logical reason to develop the WCMD is to automate the compensation for wind on the submunitions on parachutes. Since it is GPS/INS controlled, it MUST measure the drift from windage while in fall, and therefore already calculate the effect wind will have the the BLU-108s while hanging on the parachutes and adjust for that while in fall.

[jaylw314]

20 hours ago, ZeroReady said:

After years of using both 97 and 105 I still don't really understand the advantage of the WCMD. I understand it uses a spi to CCRP drop to precise location via INS magic. Or something. But doesn't the CCIP sight use LASTE info to predict where a bomb would impact, also taking wind into account? 

 

If CCIP drops didn't take wind into account, wouldn't it be kind of useless? I can CCIP a Mk82 into the window of a truck from 15,000 feet.

 

Does the 105 dispenser actually have guidance like a JDAM? Is it supposed to account for the parachutes blowing in the wind and burst at the right spot to negate the wind?

 

IIRC, one advantage of the WCMD is the ability to drop from high altitude (10,000' and up).  Without INS, CCRP would be too inaccurate and CCIP would be impossible or impractical.  

 

Also consider the ability to drop it through clouds.  Probably not politically correct, but still an option...

 

[Captain Orso]

WCMD actively controls the aim of the bomb while in free-fall, compensating for wind while in fall. CCIP only does the aiming before bomb release.

 

99.95% of mission have no wind, so you will see little to no difference between a dumb bomb falling and an WCMD, it's because in no wind situations the WCMD has very little to do.

 

If you try it now in wind, you will see that it delivers that canister right on target, even in high winds... and then you'll see the submunitions deploy and float away on their parachute and destroy every civilian vehicle in the neighboring village 300 - 400 meters away.

[Frederf]

CCIP/CCRP with dumb CBUs will compensate for wind. It knows that the submunitions will drift and will direct a delivery such that the dispense point is upwind.

WCMD both flies to the calculated dispense point against any wind and has a calculated dispense point which takes subsequent drift of the submunitions into account.

[Captain Orso]

13 hours ago, Frederf said:

CCIP/CCRP with dumb CBUs will compensate for wind. It knows that the submunitions will drift and will direct a delivery such that the dispense point is upwind.

WCMD both flies to the calculated dispense point against any wind and has a calculated dispense point which takes subsequent drift of the submunitions into account.

Oh really. And how does the board computer know the direction the wind is blowing and the strength?

 

If CCIP/CCRP already did it all, there would be no requirement for an extremely expensive WCMD, would there.

[Frederf]

The airplane tells the WCMD before release wind info. It's part of the data transferred over 1760 bus. The fact that computed releases of dumb weapons account for submunition drift would make WCMD irrelevant is your opinion.

Edited August 28, 2021 by Frederf

[Captain Orso]

Go drop an WCMD in winds and report the results. I'm tired of trying to spoon feed those resistant to evidence.

[Frederf]

We may have a misunderstanding. I'm talking about the real A-10 and WCMD, not DCS behavior.

[jaylw314]

9 hours ago, Captain Orso said:

Oh really. And how does the board computer know the direction the wind is blowing and the strength?

 

If CCIP/CCRP already did it all, there would be no requirement for an extremely expensive WCMD, would there.

 

The "on board computer" (I assume you're referring to the EGI) and even a student pilot would have the ability to figure out the wind strength and direction by comparing the aircraft's ground speed (using, say a GPS or landmarks) against the measured direction and speed (using the airspeed indicator and compass).  That's precisely how you figure out what the wind is doing.  To imply that information is not available to the aircraft is incorrect.  Whether the RL aircraft or DCS aircraft do that, I can't confirm, but my 90's era aviation GPS does.

 

 

[Captain Orso]

3 hours ago, Frederf said:

We may have a misunderstanding. I'm talking about the real A-10 and WCMD, not DCS behavior.

 

I've been talking about both. On the one side, arguing that the way it currently works in DCS, can't be the way it works in Real-Life™. Then explaining my experiences in using WCMD's in DCS.

 

1 hour ago, jaylw314 said:

 

The "on board computer" (I assume you're referring to the EGI) and even a student pilot would have the ability to figure out the wind strength and direction by comparing the aircraft's ground speed (using, say a GPS or landmarks) against the measured direction and speed (using the airspeed indicator and compass).  That's precisely how you figure out what the wind is doing.  To imply that information is not available to the aircraft is incorrect.  Whether the RL aircraft or DCS aircraft do that, I can't confirm, but my 90's era aviation GPS does.

 

 

No, I'm talking about the IFFCC (Integrated Flight & Fire Control Computer). EGI (Embedded GPS & Inertial Navigation System) is for navigation.

 

If you think EGI is calculating wind speed and direction, then it must be storing the results, and it must be viewable. I'd surely like to know how to look at this information.

 

If you think anything you can discern from measuring your flight heading deviation will be anywhere near close enough to accurately drop a bomb on target from 15,000 feet, I think you have a very vivid fantasy.

[Frederf]

You can see the wind readout on the CDU. That comes from this kind of vector subtraction as described above. EGI knows motion, orientation. ADC knows TAS. What the wind direction and magnitude must be for those other vectors to mesh is trivial. Notably this calculation is impossible while on the ground and you'll find the CDU wind readout won't work on the ground.

 

From the wind the airplane inhabits an assumption can be made about wind elsewhere. This is called the wind model and is constrained to be 0 speed at some distance below the surface. It's not perfect but it's a reasonable approximation. Notice that on the LASTE section of the CDU you can manually enter these values if you have better data.

 

Computed delivery takes wind into account for slick bombs as well as compound drag devices like Mk 82 AIRs and CBUs. The drag changes mid flight and the computer knows this patching the two together. Other unguided weapons the computed delivery helps with: rockets, illumination flares.

 

Wind actually affects low drag bombs not a lot. The major influence in wind is the crab angle (and ground speed) of the releasing platform. If you replaced the airplane with a roller coaster track so that the bomb initial velocity was the same then the wind influence could be seen to be small. High altitude level bombing is not known to be super accurate but allowances are made for wind drift regardless as it's better than not.

 

Even as far back as WWII wind drift off the airplane track line was accounted for. It absolutely has been a factor 1960s onward for computed deliveries. The computed also considers Coriolis force, pitch rate, yaw rate, air density due to temperature and pressure, etc.

[jaylw314]

2 hours ago, Captain Orso said:

If you think anything you can discern from measuring your flight heading deviation will be anywhere near close enough to accurately drop a bomb on target from 15,000 feet, I think you have a very vivid fantasy.

 

That's garrulous and uncalled for.

 

The calculated wind is on the LASTE wind page in the upper right (also in the STRINFO page).  If you enter data in the LASTE wind page, it overrides the calculated value.  I don't know whether the value in DCS is actually calculated from position and air data or just copied from the mission settings, though there is not a practical difference in DCS

 

 

Edited August 28, 2021 by jaylw314