LAYDOWN & DIVE LAYDOWN Problem

[giaco1]

Good morning, gentlemen

I noticed that in LAYDOWN mode, all the bombs impact long if the planned speed is maintained, otherwise if the speed is reduced, the bombs land short.

The LAYDOWN mode should not be affected by speed, it's supposed to calculate a release solution using the fire control computer. However, it seems that the bombs are being released as in DIRECT mode.

Have you encountered this issue?

THX

[Zabuzard]

Please make sure you are actually using TAS not IAS.

Speed does affect the release solution because it impacts the Drag Coefficient. Wrong Drag Coefficient leads to wrong ballistics.

Could you supply a video and/or track showing your issue? Im sure we can then easily identify the cause of the problem (be it you or actually a bug).
Note that when you supply a track we also need a screenshot of what you entered into your Bombing Tool, since that otherwise is not captured.

Cheers

[giaco1]

Hi, yes i use TAS, tomorrow i provide you a video and track, thx for the support!

[Yannick Pancake]

I've obeserved this "Issue" as well, but at least on my side it was an error on my side. In general the Laydown Mode should be used with an IP and the reticle is just for visualization of the targets position. But in DCS I find this not very usable so I use it more as a CCRP. I found that I'm hitting long if my plane isn't stabilzed. As soon as I'm flying a properly trimed and stabilized plane I can hit a target within 50ft with MK82 Air. I assume that the Bombing Calculator + Sight combination isn't fast enough to process the target location accurately. 

[BJ55]

On 1/22/2025 at 4:23 PM, Yannick Pancake said:

In general the Laydown Mode should be used with an IP and the reticle is just for visualization of the targets position.

Should or may?

Is Laydown mode simply a Direct mode + a timer that starts when weapon release button is depressed? By the way, I'm still having the same bad results, even when flying with precision the profile, then I started to make my own "add-subtract" tables, for example L Mk-82SE 400TAS 1000ft 2.5nm 44300lbs: -10mil (64mil instead of 74).

[Zabuzard]

Its not a timer. It uses your INS vector to accurately compute that you travelled the entered release range.

That means that you for example do not have to fly the prepared altitude or speed, you can fly up and down, as well as change the throttle during your attack run while you hold down the bombing button.

You should meet the planned profile at the moment of release though, so that your entered Drag Coefficient matches.

In regards to reticle vs VIP, both are valid. They will both match. When you are above the IP, your reticle will be on the target and vice versa. So pick whichever is better in your particular situation.

[Yannick Pancake]

As far as I know, it was a "should" 

 

I can try to make a Clip for you in the next days, when I'm back home

[BJ55]

Thanks for the info Zabuzard, better if I read again the Aircrew Weapons Delivery Manual... The problem is that If I release when above the IP the 82SE high drag fall long, that's why I must subtract 10mils from the bombing computer value (and start releasing before reaching the IP).

[Zabuzard]

Thanks for the info Zabuzard, better if I read again the Aircrew Weapons Delivery Manual... The problem is that If I release when above the IP the 82SE high drag fall long, that's why I must subtract 10mils from the bombing computer value (and start releasing before reaching the IP).

then there is either a bug or a user error.
perhaps u can share a video or track+screenshot of bombing table :)

[BJ55]

One of the two... Unfortunately I'm unable to share a video and the tracks have issues (see https://forum.dcs.world/topic/361617-jester-speed-call-out-on-loop/#findComment-5547877 ) , I have a screen took after a bomb run:

When I don't use my corrections I follow Aero4000 suggestion:  https://forum.dcs.world/topic/357226-laydown-cbu-87-falling-long/#findComment-5563802  (there you can find the simple training mission I'm using).

 

[Zabuzard]

One of the two... Unfortunately I'm unable to share a video and the tracks have issues (see https://forum.dcs.world/topic/361617-jester-speed-call-out-on-loop/#findComment-5547877 ) , I have a screen took after a bomb run:

When I don't use my corrections I follow Aero4000 suggestion:  https://forum.dcs.world/topic/357226-laydown-cbu-87-falling-long/#findComment-5563802  (there you can find the simple training mission I'm using).
 

The tracks do work if the person who replays presses pause and then enters the same details into the HB UI as the user did originally doing the real session.

So track+acreenshot is usually enough to replicate it :)

[BJ55]

Here's the mission/track/screenshots. Starting point-IP 10nm, IP-TGT 2.5nm, put in active pause to fill the bombing calculator and set the weapons system, hit shift-F10 once to hide labels, turn off active pause, stabilize the aircraft for the run.

F-4_ag_train_cauc_82SE.zip

[Ornithopter]

On 2/20/2025 at 10:03 AM, Zabuzard said:

Its not a timer. It uses your INS vector to accurately compute that you travelled the entered release range.

That means that you for example do not have to fly the prepared altitude or speed, you can fly up and down, as well as change the throttle during your attack run while you hold down the bombing button.

You should meet the planned profile at the moment of release though, so that your entered Drag Coefficient matches.

In regards to reticle vs VIP, both are valid. They will both match. When you are above the IP, your reticle will be on the target and vice versa. So pick whichever is better in your particular situation.

Using BJ55's bomb table example from above, the release altitude is 1000 ft and horizontal release range is 2603 ft.    You say "You should meet the planned profile at the moment of release though, so that your entered Drag Coefficient matches."  What if the drag coefficient is more or less correct, but I'm 500 feet too high, or I'm not exactly perfectly level around the predicted time of release?  Aren't I going to still miss the target by a long way?  Are you saying that the WRCS is smart enough, without Radar or Laser ranging, to automatically adjust the Release Range based on my deviations from the originally planned profile, as long as I push and hold the bomb button at exactly the right moment? 

Additional question:  What if my initial speed or altitude are off as I overly the IP and push the bomb button to start the sequence?  Because the WRCS is doing things dynamically, that shouldn't matter, should it, as long as I am physically right over the IP?  Or does it?

Edited February 23 by Ornithopter

[Zabuzard]

32 minutes ago, Ornithopter said:

Using BJ55's bomb table example from above, the release altitude is 1000 ft and horizontal release range is 2603 ft.    You say "You should meet the planned profile at the moment of release though, so that your entered Drag Coefficient matches."  What if the drag coefficient is more or less correct, but I'm 500 feet too high, or I'm not exactly perfectly level around the predicted time of release?  Aren't I going to still miss the target by a long way?  Are you saying that the WRCS is smart enough, without Radar or Laser ranging, to automatically adjust the Release Range based on my deviations from the originally planned profile, as long as I push and hold the bomb button at exactly the right moment? 

Additional question:  What if my initial speed or altitude are off as I overly the IP and push the bomb button to start the sequence?  Because the WRCS is doing things dynamically, that shouldn't matter, should it, as long as I am physically right over the IP?  Or does it?

The WRCS will do the math dynamically. The problem is that the drag coefficient will be slightly wrong. Meaning that the WRCS will calculate with incorrect drag values for your weapon. For low drag weapons the consequences will be less severe, and it ofc depends on what kind of profile you are flying.

Edited February 23 by Zabuzard

[Yannick Pancake]

@BJ55

Sorry, I wasn't at my PC for a bit, bute here are some pictures from a Tacview - Clip.
 was using 450 TAS and 250 ft MSL, 2000ft IP/TGT Distance for I think 136 mils (Just use what it gives you), Bomb interval 0.16s and Bomb 2 on TGT.  I pickled with Pipper on center of the Target area and Bomb 2 hits pretty much where I hit. nullnull

Edited March 1 by Yannick Pancake

[BJ55]

Had the same results (109mil), that's because at that altitude and with that speed bombs are released when you depress the button (target range=release range), it's like a Direct bombing profile. When you have some spare time, try with different altitudes (500, 1000, 1500).

[Yannick Pancake]

I've tested them besides the one above with altitudes of 400, 450, 700 and 1200 ft. All pretty much on target, but more errors the higher I got (as anticipated). But no problems of hitting a target with a string of bombs. I would say I'm confident of destroying a truck with 4 bombs at 450ft agl and 500kias. 

But as mentioned above, I don't use the Laydown as intended with a visual IP, since I don't have a Human WSO + we simulate the F-4F and it never had Laydown, however it had something called CCOR in Hi and Lo. So we use it to replicate the functionality of the CCOR Lo mode. Like I described above, I set my desired drop parameters in the Bombing Table and adjust my IP to TGT range so that I get a depression of ~150mils. Then I just fly towards the target and one the piper is above the target, I pickle, and most of the time hit my intended target. 

2 hours ago, BJ55 said:

Had the same results (109mil), that's because at that altitude and with that speed bombs are released when you depress the button (target range=release range), it's like a Direct bombing profile. When you have some spare time, try with different altitudes (500, 1000, 1500).