fixed GBU 24 falling way short? Bug or user error?

[Fulcrumkiller31]

Tested on a few missions since patch. Appears to persist in single and multi player. Am I missing something? I was under the impression the GBU 24 has slightly better range as well. 

 

I get the DLZ, release about midway, the bomb falls way short.

Release angle is zero, auto lase is set to 15 seconds.

GBU24 borked.trk

[Dragon1-1]

19 minutes ago, Fulcrumkiller31 said:

auto lase is set to 15 seconds

Here's your user error. A GBU-24 needs to be lased right from the start, otherwise it won't know where it's going and will just glide ahead. It should probably be falling long, but maybe it sees the laser and does something stupid trying to get at it. The increase in range is in large part because this bomb is smarter than older LGBs, so it needs to see the laser in order to compute its trajectory.

[Fulcrumkiller31]

29 minutes ago, Dragon1-1 said:

Here's your user error. A GBU-24 needs to be lased right from the start, otherwise it won't know where it's going and will just glide ahead. It should probably be falling long, but maybe it sees the laser and does something stupid trying to get at it. The increase in range is in large part because this bomb is smarter than older LGBs, so it needs to see the laser in order to compute its trajectory.

I will test that out, and report

[Fulcrumkiller31]

Still fell well short. Tried again and waited until I was halfway through the DLZ, it barely had enough energy to hit the target. 

GBU24 borked2.trk

 

Edited August 24, 2022 by Fulcrumkiller31

[Furiz]

Definitely something wrong with GBU24, it is falling way too short, I had a drop with auto lasing set at 12 sec, and when lasing started the bomb was falling short so it did catch the laser but it couldn't reach the target. (released inside DLZ)

I was planning to test too, I'll do it when I have time.

Edited August 25, 2022 by Furiz

[Fulcrumkiller31]

11 hours ago, Dragon1-1 said:

Here's your user error. A GBU-24 needs to be lased right from the start, otherwise it won't know where it's going and will just glide ahead. It should probably be falling long, but maybe it sees the laser and does something stupid trying to get at it. The increase in range is in large part because this bomb is smarter than older LGBs, so it needs to see the laser in order to compute its trajectory.

I can’t find any documentation stating the GBU 24 needs laser energy immediately. In fact I read the opposite.

 

either way it still doesn’t work !

[5ephir0th]

Have you checked at laser DED page if the code it´s correct? Now if you hot start laser code is 0 and you have to change it.

GBU-12 works fine but i tried CBU-97 on TOSS bombing and it allways fall short too, tried on tanks at waypoint 3 on Persian Gulf instant mission hot start take off, tried from differents bearings and alwais the same, so no wind problem

[Fulcrumkiller31]

Upon further testing. The issue seems to lie with the bombs not seeing the laser when dropped from max DLZ above 15000 ft. 

With a 10 degree loft- bombs capture laser

wait a bit to around 10-12 miles bombs capture laser. 

24k ft level drop from around 14 miles M 1.2, bombs don't see the laser until they are ballistically too low to make the target (although they try).

Below 15k feet, I have a few successful hits, bombs glide like they are suppose to, but sometimes one of the two bombs never catches the laser.

Some SME feedback on discord confirms this, these bombs are pretty complicated, there is a lot more to it than dropping in the DLZ. 

 

Although I still feel like there might be some wrong behavior. 

GBU24 odd behavior.trk

Edited August 25, 2022 by Fulcrumkiller31

[Moonshine]

I have the feeling they were not primarily made to be self lased, whats the point of letting it glide for miles when you still have to get within laser range of your own laser. Might as well drop it late then. 
 

would need to test a buddy lasing scenario (or with a JTAC) to see how it behaves

edit: did some quick research online, have to correct my statement of its use case. 
 

made specifically for low level use, should not be affected by early lasing. 
 

Was an interesting read: https://www.globalsecurity.org/military/systems/munitions/gbu-24.htm

Edited August 25, 2022 by Moonshine

[Fulcrumkiller31]

"However, if the LGB guidance system detects reflected laser energy from the target designator too soon after release, it tends to pull the LGW down below its required trajectory and the bomb will impact well short of the target."  I think it totally depends on launch parameters when you should lase. good read indeed. Check out my above track.

[Moonshine]

Yeah saw that too. Weird how it says it shouldnt be affected by early lasing and then it states this paragraph
 

This bomb is not nearly as delivery parameter sensitive as is the Paveway II LGB, nor is it affected by early laser designation.

Paveway III hurt itself in confusion 

Edited August 25, 2022 by Moonshine

[Fulcrumkiller31]

21 minutes ago, Moonshine said:

Yeah saw that too. Weird how it says it shouldnt be affected by early lasing and then it states this paragraph
 

This bomb is not nearly as delivery parameter sensitive as is the Paveway II LGB, nor is it affected by early laser designation.

Paveway III hurt itself in confusion 

 

Lol it is certainly odd, wish I didn’t get the immediate cannot reproduce tag. something is clearly off.

[Furiz]

So this is how GBU-24 behaves,

 

this track is when I lased myself, it was going to fall miles short so I activated laser, (I probably released too early but... the DLZ was ok right?) the bomb picked up and flew directly to target: gbu24 self lase strange flight.trk

 

then I let the auto lase option to do it and it didn't lase on time cause the timers were wrong: gbu24 auto lasing late.trk

 

so this must be cause of que range set too high and we get release que well ahead of time, or we have to lase 1 min early for the bomb to fly correctly, in my test it was falling well away from the point of impact.

Edited August 25, 2022 by Furiz

[Fulcrumkiller31]

55 minutes ago, Furiz said:

So this is how GBU-24 behaves,

 

this track is when I lased myself, it was going to fall miles short so I activated laser, (I probably released too early but... the DLZ was ok right?) the bomb picked up and flew directly to target: gbu24 self lase strange flight.trk

 

then I let the auto lase option to do it and it didn't lase on time cause the timers were wrong: gbu24 auto lasing late.trk

 

so this must be cause of que range set too high and we get release que well ahead of time, or we have to lase 1 min early for the bomb to fly correctly, in my test it was falling well away from the point of impact.

 

Yeah same thing on my end. The bomb just takes a nose dive.

GBU24 odd behavior2.trk

Edited August 25, 2022 by Fulcrumkiller31

[Fulcrumkiller31]

I tried it with the hornet and it does the same thing, except the DLZ is much smaller. so it captures the laser. 

[Frederf]

PW3 are different than PW2. The weapon should fly in a "bump up" glide to extend its range regardless of laser energy and should arrive to target area (or beyond) if not guided. The weapon has an INS, barometric sensor, digital autopilot. It decides what delivery profile to do based on sensed data on release: loft-level, dive, and I think a third one. It has a break level ceiling of I think 15,000' PA.

[Furiz]

In other words it shouldn't fall short a few miles?

Edited August 25, 2022 by Furiz

[Fulcrumkiller31]

9 minutes ago, Furiz said:

In other words it shouldn't fall short a few miles?

 

Exactly my point lol. but "can not duplicate" -_-

[Frederf]

I'll make a track when I get home

[Phantom88]

I know this is a bit OT but I didn't want to start another thread as my question is somewhat related.

Using The GBU 12 I'm finding my bombs are dropping seconds After countdown to release? And still hitting target...Is this normal? or something New I missed?ThankYou in advance.

[Fulcrumkiller31]

FYSA this has been recreated both above 15k and below 15k, auto lase and manual lasing through the whole time. Bombs will fall short regardless, fail to capture laser, or capture but fail to pull back up and hit. 

If released near the bottom  half of the DLZ the bomb has a chance to hit. I implore yall to test this for yourself! 

[rob10]

The other thing I haven't seen mentioned yet in this thread but should be remembered in DCS (and may be part of the problem here): the pod lasers in DCS are basically an 8 km (IIRC) long light sabre.  If the tip of this light sabre (or some part of it between the tip and your aircraft) doesn't intersect with anything you get no reflection point and thus nothing for laser guiding bomb/missile to guide on.  If you point it at something 20 km away, the end gets suspended in air part way to target (until you close the range to about 8 km) so gets no guidance.  That would fit with some of the testing above where it seems to ignore it or the case where the laser was activated later (likely after it was in range) rather than at max range for the missile.  As was commented above, if you're trying to launch at max range from altitude you're going to be better off to have buddy lasing occurring.

[Fromthedeep]

The 24 is such a complex beast that it's basically impossible to reverse engineer the implementation without being intimately familiar with the weapon IRL. There really should be much better documentation as to what exactly is simulated from the different profles in mode 1, otherwise it's going to require hundreds upon hundreds of drops to get some kind of testing data and try to figure out what works and what doesn't. So, in my opinion there should be a clear and comprehensive writeup about the expected implementation and from there we can determine how well it matches up. 

[Fulcrumkiller31]

Why is this still labeled “cannot reproduce”? 

 

[NineLine]

This is reported, thanks.