3 second lasing/AGR prior to dropping a GBU38 - Is it weapon related or F-16 related?

[nickos86]

Hi,

The increased accuracy followed by 3sec of lasing or AGR - is it a weapon thing? Is it relevant to all modules? 

Or is it a platform thing? In this case, what mechanism was flawed and now is modeled correctly? ED, could you please share some info regarding this fix? 

Thanks.  

• Fixed: TGP+GBU38 = 15-20m Miss. Note: 3 Second laser or AGR required before release for increased accuracy.

[Hobel]

vor 16 Stunden schrieb nickos86:

Hi,

The increased accuracy followed by 3sec of lasing or AGR - is it a weapon thing? Is it relevant to all modules? 

Or is it a platform thing? In this case, what mechanism was flawed and now is modeled correctly? ED, could you please share some info regarding this fix? 

Thanks.  

• Fixed: TGP+GBU38 = 15-20m Miss. Note: 3 Second laser or AGR required before release for increased accuracy.

If you laser  the target short with the tgp you get the most accurate coordinates and the bomb has the best CEP. 
Equivalent to pre plant.   

Without the laser, the determination of the coordinates with the tgp should become less accurate the further away you are from the target.

[Py]

3 hours ago, Hobel said:

If you laser  the target short with the tgp you get the most accurate coordinates and the bomb has the best CEP. 
Equivalent to pre plant.   

Without the laser, the determination of the coordinates with the tgp should become less accurate the further away you are from the target.

Few questions:

1. How does laser vs radar vs PP accuracy compare?

2. And is there something that needs to be actively done to range with ground radar, or is it automatic?

3. Is the precision maintained if lased/GRd points are saved as markpoints?

[Nealius]

4. Is there a recomended technique/range given the limited laser range modeled in DCS?

[Hobel]

vor 28 Minuten schrieb Py:

Few questions:

1. How does laser vs radar vs PP accuracy compare?

2. And is there something that needs to be actively done to range with ground radar, or is it automatic?

3. Is the precision maintained if lased/GRd points are saved as markpoints? 

1. How does laser vs radar vs PP accuracy compare? Laser and PP should be the same ingame.   i can't say anything specific about the radar, but it's a good question

2. And is there something that needs to be actively done to range with ground radar, or is it automatic?  hm I can not say exactly or I do not understand you question correctly, but basically it is always automatic

3. Is the precision maintained if lased/GRd points are saved as markpoints?   Should be, therefore yes

4. Is there a recomended technique/range given the limited laser range modeled in DCS?  laser Range ist ~16-17nm
Marking is still possible without the laser, but it is no longer as accurate. I don't have exact data at the moment but if you are attacking soft targets it should be accurate enough even without the laser.

Edited July 28, 2023 by Hobel

[nickos86]

Why would the GBU38 procedure be different vs the GBU31? Is the 38 a test bed for JDAM FM and features? 

[Hobel]

vor 2 Stunden schrieb nickos86:

Why would the GBU38 procedure be different vs the GBU31? Is the 38 a test bed for JDAM FM and features? 

Is the same principle.  The tgp caused strong "drifts" before the update and with the GBU38 it could be reproduced best. 

[nickos86]

20 hours ago, Hobel said:

Is the same principle.  The tgp caused strong "drifts" before the update and with the GBU38 it could be reproduced best. 

So it should have been:

"Fixed: TGP+GPS guided weapons = 15-20m Miss. Note: 3 Second laser or AGR required before release for increased accuracy."

There should be nothing special about the GBU-38 in comparison to the rest of the GPS weapons. 

 

[Py]

On 7/28/2023 at 5:35 PM, Hobel said:

2. And is there something that needs to be actively done to range with ground radar, or is it automatic?  hm I can not say exactly or I do not understand you question correctly, but basically it is always automatic 

By something active I mean when is the range update from AGR triggered?

A) Any time the TGP points anywhere, AGR sweeps it and updates range
B) When a position is area tracked? point tracked?

Also must the AGR scan height be manually adjusted to cover the point targeted by TGP?

[LastRifleRound]

The answer is A, within a certain range.

AGR is automatically used if TGP is SOI, you are in AG master mode and you're within xnm of what it's looking at (I don't know the exact range). If the laser is used, the system will prefer it over the radar range.

As far as differences, I don't know what's modeled in DCS. IRL, PP (or "absolute" positioning) is always more accurate than TOO (or "relative" position). This is because relative positioning has an additional computational hurdle in determining target position.

As for sensor accuracy, the laser is generally more accurate (barring things like smoke and cloud cover which affect the two sensors differently). The radar increases in accuracy the closer and higher angle you are to the spot you're looking at. The Mirage models this phenomenon when doing radar Nav updates or PI mode bombing. Though that radar can't be slewed and looks at a fixed point, the concept is the same. In the Mirage for best results you need a dive and to keep the jet steady so the computer can figure out the center of the radar cone and take the range from that. The Viper does this part for you by pointing the beam at the TGP target (or CCIP pipper or HUD tgt etc).

[SickSidewinder9]

Even before this, I noticed that if the TGP is a vehicle, the laser is kinda needed to hit it.  You can actually see the coordinates in the TGP cam MFD change.   I assume that without the laser, the TGP is guestimating the coordinates behind and below the vehicle/building/bridge (from its PoV).

That is the reason for all this and the new instructions, I'd suppose.  And it would be somewhat realistic.  It wouldn't effect accuracy of drop onto preplanned coordinates or mark points, but the mark point coordinates could still be wrong if not lasing when marking.

Make sure laser is armed and pull trigger.  TMS up if you need to mark, or weapon release if you're in the drop zone.  The game seems to make up for not having a 2 stage trigger on your stick, which is pretty nice.  Not even sure you need the full 3 seconds either.  It will assign whatever coordinates you're getting to the GPS guided weapon upon launch.  Increasing the dive angle of the bomb will also help with accuracy, although it reduces range.

Edited August 11, 2023 by SickSidewinder9

[LastRifleRound]

On 8/11/2023 at 5:16 PM, SickSidewinder9 said:

Even before this, I noticed that if the TGP is a vehicle, the laser is kinda needed to hit it.  You can actually see the coordinates in the TGP cam MFD change.   I assume that without the laser, the TGP is guestimating the coordinates behind and below the vehicle/building/bridge (from its PoV).

That is the reason for all this and the new instructions, I'd suppose.  And it would be somewhat realistic.  It wouldn't effect accuracy of drop onto preplanned coordinates or mark points, but the mark point coordinates could still be wrong if not lasing when marking.

Make sure laser is armed and pull trigger.  TMS up if you need to mark, or weapon release if you're in the drop zone.  The game seems to make up for not having a 2 stage trigger on your stick, which is pretty nice.  Not even sure you need the full 3 seconds either.  It will assign whatever coordinates you're getting to the GPS guided weapon upon launch.  Increasing the dive angle of the bomb will also help with accuracy, although it reduces range.

 

I doubt ED fixed this, as it's been an issue since the A10 first came out.

The laser (or any other ranging sensor), doesn't interact with objects at all, only terrain. It was SOP to lase the bottom of a vehicle to prevent it from going through the vehicle and designating a spot behind it. This is why you are seeing better accuracy in a dive, because as you adjust the pod in this posture you are getting closer and closer to designating a spot underneath the vehicle. (By going more through the top of the vehicle and less through the side).

The changes in coordinates you're seeing with lase vs no lase is due to imprecise height-over-target calculations that arrive from not using an active sensor to vet slant range (height over target is assumed to be your jets current altitude).

Edited August 16, 2023 by LastRifleRound

[SickSidewinder9]

On 8/16/2023 at 12:05 PM, LastRifleRound said:

I doubt ED fixed this, as it's been an issue since the A10 first came out.

The laser (or any other ranging sensor), doesn't interact with objects at all, only terrain. It was SOP to lase the bottom of a vehicle to prevent it from going through the vehicle and designating a spot behind it. This is why you are seeing better accuracy in a dive, because as you adjust the pod in this posture you are getting closer and closer to designating a spot underneath the vehicle. (By going more through the top of the vehicle and less through the side).

The changes in coordinates you're seeing with lase vs no lase is due to imprecise height-over-target calculations that arrive from not using an active sensor to vet slant range (height over target is assumed to be your jets current altitude).

 

If you say so, but it definitely makes it so you can hit stationary vehicles with JDAMs.

[TobiasA]

Am 17.8.2023 um 23:33 schrieb SickSidewinder9:

If you say so, but it definitely makes it so you can hit stationary vehicles with JDAMs.

Depends, they become a lottery when dropped at max range from 22000ft altitude. A truck is all they can do, they will often fail on even lightly armored vehicles.

I wish we had the GBU-54 on the Viper. When going against vehicles, pick LGB or mavs.

[WizzRD]

On 7/27/2023 at 1:48 PM, nickos86 said:

The increased accuracy followed by 3sec of lasing or AGR - is it a weapon thing? Is it relevant to all modules? 

It´s a weapon/ TPOD thing that should be relevant to all modules.

Basicly, Target Coords generated by the TPOD are not accurate enough to hit a small target at max. possible distance. By lasing the target shortly before dropping you do increase accuracy but it may well be that ED has it overcorrected now (have not run any tests yet). In general you should not drop a JDAM on anything smaller than a house. For Movers use LGBs.

If you want to read up on this, search for:

"AN ANALYSIS OF TARGET LOCATION ERROR GENERATED BY THE LITENING POD AS INTEGRATED ON THE AV-8B HARRIER II"

[Tenkom]

I have a question regarding this.

When I hold the laser button while looking at the tgp I can see the coordinates change but when I release they change back to what they were before I lased.

Do I have to hold the laser button while pickling the JDAM for the increased accuracy?

[Hobel]

Am 29.7.2023 um 11:20 schrieb nickos86:

So it should have been:

"Fixed: TGP+GPS guided weapons = 15-20m Miss. Note: 3 Second laser or AGR required before release for increased accuracy."

There should be nothing special about the GBU-38 in comparison to the rest of the GPS weapons. 

Yes

Am 11.8.2023 um 18:26 schrieb LastRifleRound:

As far as differences, I don't know what's modeled in DCS. IRL, PP (or "absolute" positioning) is always more accurate than TOO (or "relative" position). This is because relative positioning has an additional computational hurdle in determining target position.

This is also the case in DCS.

With the F16:

starting with the best accuracy.

1.PP
2.TGP+ Laser
3.TGP

Am 16.8.2023 um 20:05 schrieb LastRifleRound:

The laser (or any other ranging sensor), doesn't interact with objects at all, only terrain. It was SOP to lase the bottom of a vehicle to prevent it from going through the vehicle and designating a spot behind it. This is why you are seeing better accuracy in a dive, because as you adjust the pod in this posture you are getting closer and closer to designating a spot underneath the vehicle. (By going more through the top of the vehicle and less through the side).

This has not been the case for a long time,Buildings and vehicles stop the laser.

Showcase :
 

 

 

vor 1 Stunde schrieb Tenkom:

I have a question regarding this.

When I hold the laser button while looking at the tgp I can see the coordinates change but when I release they change back to what they were before I lased.

Do I have to hold the laser button while pickling the JDAM for the increased accuracy?

currently you have to keep it pressed or drop it quite soon after.

 

Edited September 15, 2023 by Hobel

[Falconeer]

It has a reason why they developed bombs like GBU-49 and GBU-54.

If you want to be that accurate to take out a vehicle, use laser guidenance or a Maverick

Edited September 15, 2023 by Falconeer