[DCS vs. IRL] CCIP - How does it work....so well?

As many of us have found, CCIP can be laser accurate in ideal conditions. I have been wondering how this would work in the real world, as to me it seems we are missing some potential error factors in DCS (which maybe are not, or can not be modeled for some reason).

My thoughts:

  1. The CCIP ranging cannot be calculated using the Radar altimeter as a reliable source as in a steep dive it’s not going to be pointing directly at the ground. You can also use CCIP above the effective altitude that the radar altimeters work at.

  2. Barometric altimeter also does not make sense, as using the standard 29.92inHG would mean that 0ft barometric does not coincide with 0ft AGL in most conditions. On the other hand, setting your altimeter to the local barometric pressure at takeoff to have 0ft baro = 0ft AGL, would only work near the airport you take off from - any change in weather would create a potentially large margin of error which to correct for you would need a update on air pressure from the target area - at the time that you get there.

  3. INS - are INS systems precise enough for this? And then shouldn’t drift also become an issue over time?

  4. GPS - are the GPS updates often enough? What about cases without or before widespread GPS?

From simple reports as much as wikipedia on unguided bombing precision, it would seem some of the factors I mentioned must be in play otherwise the need for PGMs, outside of areas with a threat requiring the standoff range would seem unnecessary.

Just some thoughts, if anyone has more ideas or info, I’d love to hear it.

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Think it’d help the discussion if you specified a plane or a number of planes. Par example, some planes calculate CCIP not with RADALT but a system such as the FCR or a system like ARBS.

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It is… complicated.
A precise INS+GPS is a good start, but you also need to know the target elevation, which can come from elevation data saved in the plane, or (even better) from a radar or laser looking at the target.

But a few of the other guys can explain it better, I am sure about that.

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Primarily I am flying the Hornet, but had the same curiosity for the A10-C for example. I know the Harrier is a bit different from the others.

Right, so in the case of laser that would be limited to having for example a TGP.
As for Radar, that can work for our fighters, but not something like the A-10C.

As for the INS+GPS, this makes most sense to me - but if the data is that good, and can update in dynamic enough a manner, why don’t we see more of an option to use INS/GPS altitude on things like say, the HUD for example?

The warthog knows the terrain via the DTSAS (digital terrain system application software). It can calculate CCIP intersections with that terrain if the EGI is good. You can show GPS altitude on the CDU which you can replicate on an MFD.

I see @klarsnow started typing so I’ll be quiet :smiley:

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CCIP is literally mil cranked bombing, where the computer is cranking the mils dynamically for you as you maneuver and fly the aircraft. It is subject to the same issues in delivery accuracy.

As for determining slant range to the target, all of the above can be used, but will have varying degrees of inaccuracy unless an exact range down the pipper to complete the bombing triangle is acquired. IE it can calculate the bombing triangle using the radar altimeter, but unless its over perfectly flat terrain, that’s not going to be accurate. Usually usable as a backup method, but not something you wanna plan on.

Most 4th gen aircraft (F-16/18/15E) use the radar ranging thru the pipper to give precise slant range to the target and complete the bombing triangle.

The TGP can also be slaved to the pipper in most cases and the laser fired to give precise ranging and also complete the bombing triangle.

The thing to keep in mind is that a stable platform is very much required, the computers can only deal with the data being given by the INS and it is not instantly able to account for increases in G/roll/acceleration. So you still fly CCIP passes just like you would a mil bombing pass, with stable parameters. A 0.1 G change can be enough to send a bomb long or short.

Using the EGI/ terrain elevation data is only as good as your terrain database. In the strike eagle it was considered a very degraded mode due to the inaccuracy inherent with terrain databases. The other thing to think about with that is what the resolution of the mesh they are using is, and what if you are trying to drop on something that’s not the ground… like say the roof of a building… That the terrain database doesn’t take into account

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During the Cold War, laser range finders were really popular in attack aircraft to get accurate slant range for bombing solutions. Jaguar, Harrier GR.3, Su-17, Su-25 or MiG-27 just to name a few. Radar ranging seems generally favorable because it is less affected by smoke or clouds, but is more complex and expensive. In fact, I heard that the primary reason the AV-8B+ was upgraded with a radar was to get target ranging at night (versus the optical ARBS of the original AV-8B, which provided very accurate slant range but only at day).

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Love the info guys, thanks!

I find even in DCS you can swing about right before weapon release and still nail the target dead on if you get the pickle to occur right as the pipper is directly on target (accounting for input delay and muscle movement delay). So knowing that we have limits currently, getting more insight into how it’s supposed to work and with that limits would is good.

For example, DCS does seem to be aware of the tops of buildings when using CCIP, or bridges etc.
I figured then that hitting the broadside of a tall bridge should be more difficult, especially if the computer is working with the terrain elevation. In the case of bridges, I try to aim down the length so that long/short is less of an issue.

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Also, I’m not sure how much any CCIP takes winds into account. The higher you are, the more chances for winds to be variable in speed and/or direction as the bomb falls.
CCIP was never meant to compensate for that. As the weather in real life has infinite levels of complexity compared to what a sim can model, I think that’s why CCIP was never ideal for 500lb or smaller weapon that requires decent accuracy to destroy the target.

If it’s a Mk84 I’m sure CCIP is plenty good enough. :slight_smile:

This. (So we do have some form of ag radar ;)) And for HMCS enabled DTOS(F16) I recall the tgp laser is also used as a ranger. Not sure if the hornet has similar capability (HMCS enabled auto bombing) but probably.

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No we don’t have any sort of ag radar, right now it’s not simulating any sensor providing the data. It just seems to be doing it “magically”.

I queried wags about this a while back, because in a real jet, where and how the system is getting height above target or slant range is very important, and isn’t discussed anywhere. response I got was essentially it’s all planned, but right now it’s all using perfect world data. IE it knows because it’s a game and has perfect data what the slant range/bombing triangle is.

If it was doing ag ranging you would see your aa radar display change every time you strafed and there would be Additional symbology in the hud.

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Afaik the mirage 2k does simulate using the radar to get slant range.

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