TPOD and JDAM, what am I doing wrong?

[Nasder]

Prior to 2.5.6 I had no problems using JDAMs but something has changed and I don't know if it's me doing something wrong or if it's a bug.

 

So I have a target close to waypoint 1 (Tunb Kochak Airfield), not directly at it but close by.

I let the JDAM spend the time needed to be ready.

Set mode to TOO

EFUZ to Instant

Go into JDAM display, press MSN button.

Switch to the FLIR, Select waypoint 1 and press WPDSG

FLIR points automatically at the location (Hooray, new feature?)

I slew it to the target and press TDC.

 

The coordinates in the MSN screen update and the FLIR is now pointing nowhere, I see ocean and other things fly by.

 

Checking the HSI, I see no dynamic dropzones and my HUD say I am 7-9 minutes from being able to drop. I point in the direction where the time to drop slows down and it's away from my target by around 58NM.

Target is at Tunb Kochak airfield in PG Map, the coordinates for the drop is close to Khasab. Nowhere close to where I pointed my TPOD.

JDAM Y U NO WRK.trk

Edited February 16, 2020 by Nasder
Added Track File

[ex81]

I`m afraid I`m no real help, but I can tell you that I had have often bad results when using TOO Mode.

I believe this is why you can not put in the last decimal.

Never had problems when using PP Mode.

 

Hope others will give more detailed reasons.

[Mnf]

I hade the same problem, it seems from the new TGP feature (slews the TGP to waypoints)

It is reported here also

[CHECKING] TGP not working with LAser guided bombs?

https://r.tapatalk.com/shareLink/topic?share_fid=74365&share_tid=263417&url=https%3A%2F%2Fforums%2Eeagle%2Eru%2Fshowthread%2Ephp%3Ft%3D263417&share_type=t&link_source=app

 

 

Sent from my iPhone using Tapatalk

[CarbonFox]

I've honestly had no problem hitting targets with JDAMs since the patch. Using LGBs has been another story as the laser code doesn't seem to input.

[Harker]

This thread is useful: https://forums.eagle.ru/showthread.php?t=258579 and offers a detailed procedure.

[Ziptie]

Prior to 2.5.6 I had no problems using JDAMs but something has changed and I don't know if it's me doing something wrong or if it's a bug.

 

So I have a target close to waypoint 1 (Tunb Kochak Airfield), not directly at it but close by.

I let the JDAM spend the time needed to be ready.

Set mode to TOO

EFUZ to Instant

Go into JDAM display, press MSN button.

Switch to the FLIR, Select waypoint 1 and press WPDSG

FLIR points automatically at the location (Hooray, new feature?)

I slew it to the target and press TDC.

 

The coordinates in the MSN screen update and the FLIR is now pointing nowhere, I see ocean and other things fly by.

 

Checking the HSI, I see no dynamic dropzones and my HUD say I am 7-9 minutes from being able to drop. I point in the direction where the time to drop slows down and it's away from my target by around 58NM.

Target is at Tunb Kochak airfield in PG Map, the coordinates for the drop is close to Khasab. Nowhere close to where I pointed my TPOD.

 

There is currently an issue where the FLIR "can at times bounce" after using WPDSG via the HSI or SA page.

 

What I have found to get around that issue is:

 

(assuming you have aligned the JDAM, if not do so)

 

MASTER ARM on

AG MODE selected

OSB pushbutton to select JDAM

OSB pushbutton TOO

OSB pushbutton JDAM DISPLAY

OSB pushbutton MSN

WPDSG to slave FLIR

NWS to undesignate waypoint target (should leave FLIR at location)

FLIR SOI

SCS in direction of FLIR display for PTRK mode

TDC slew to target

TDC depress (to designate target)

Verify coordinate entry

HSI will now display bearing and launch zone

Weapon release

 

 

Cheers,

 

Don

[Nasder]

There is currently an issue where the FLIR "can at times bounce" after using WPDSG via the HSI or SA page.

 

What I have found to get around that issue is:

 

(assuming you have aligned the JDAM, if not do so)

 

MASTER ARM on

AG MODE selected

OSB pushbutton to select JDAM

OSB pushbutton TOO

OSB pushbutton JDAM DISPLAY

OSB pushbutton MSN

WPDSG to slave FLIR

NWS to undesignate waypoint target (should leave FLIR at location)

FLIR SOI

SCS in direction of FLIR display for PTRK mode

TDC slew to target

TDC depress (to designate target)

Verify coordinate entry

HSI will now display bearing and launch zone

Weapon release

 

 

Cheers,

 

Don

 

Thanks! I'll try that out today. During my testing I never undesignated the waypoint target proir to making FLIR SOI, so undesignating boresighted my FLIR.

 

Thanks again for the tip!

 

Update: The moment I hit NWS/undesignate, even without FLIR as SOI. The FLIR moves away. But designating a target without having a target waypoint still works fine, so I'll just use the old fashioned way of doing it until the issue is resolved.

Edited February 19, 2020 by Nasder

[Vanguard]

Dropping GBU-38s from an A-10C, the bomb lands within pixels of the designated SPI. From the F/A-18C, PP mode,TOO mode, TPOD, Waypoint, whatever... the bombs land about 1 tank length away, from 15k ft, 20k ft, also... whatever. Yes, using precise, and zooming in as far as I can and ensuring the lat/lon at the top matching the precise unit local (I unhid the units to verify) from F10 and used the WP Editor tool.

 

Is the GBU-31/38 a shared resource between the two aircraft, or are they just sharing textures and have completely different computational modeling?

 

Edit:

From wikipedia, it has about 7m accuracy, maybe I'm just expecting too much from it, but it doesn't explain why it's so accurate dropping from the A-10C, except the obvious, which is I dropping it low and slow and it's falling on a much steeper decent.

 

Also, maybe I'm losing my mind, but I seem to recall the TGP recording the ground location based on the slant angle, and at a shallow angle of attack, the point on the ground would be behind the unit you were targeting, and lasing the target would correct that, but flying today, I noticed when I lase, the coords in the TGP remain the same, and the mark point generated is the same, lasing or not. (I'm referring to A-10C here). Was I dreaming or smoking dope, or has it changed?

Edited February 19, 2020 by Vanguard

[Ziptie]

Thanks! I'll try that out today. During my testing I never undesignated the waypoint target proir to making FLIR SOI, so undesignating boresighted my FLIR.

 

Thanks again for the tip!

 

Update: The moment I hit NWS/undesignate, even without FLIR as SOI. The FLIR moves away. But designating a target without having a target waypoint still works fine, so I'll just use the old fashioned way of doing it until the issue is resolved.

 

I forgot to add the step highlighted in bold:

 

(assuming you have aligned the JDAM, if not do so)

 

MASTER ARM on

AG MODE selected

OSB pushbutton to select JDAM

OSB pushbutton TOO

OSB pushbutton JDAM DISPLAY

OSB pushbutton MSN

WPDSG to slave FLIR

Slew FLIR with TDC slightly

NWS to undesignate waypoint target (should leave FLIR at location)

FLIR SOI

SCS in direction of FLIR display for PTRK mode

TDC slew to target

TDC depress (to designate target)

Verify coordinate entry

HSI will now display bearing and launch zone

Weapon release

 

 

Cheers,

 

Don