JDAM and Coordinates Issues
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I dont think is necesary to save to DTC after assigning a steerpoint as target at the Recon page, just accepting it is enough.- If the target doesnt appear at the planned steerpoint, you should readjust the SP1 with TMS down/CZ to reset all deltas introduced previously
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Update: I tested the JDAMs and JSOWs in the training mission in the default Korean theater. I selected parts of the airfield at steerpoint 4 (not the mission target steerpoint). I got all good hits using FCR only, TGP only and Precision Steering only (done in UI with F-16 already airborne and no saving to DTC) methods. No DED target coords were entered.
Why do I get this feeling it’s somehow less accurate in the Balkans theater where I seem to have problems getting the bombs to hit their targets. Hmmm…
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Hi,
In the F-16CM 34-1-1 manual, it says…
3.4.15.2 JDAMs and SDBs single pass – multiple targets procedure
"The F-16 cannot release JDAMs in ripple mode so in order to release multiple JDAMs in one pass on multiple targets you should follow these steps:
1. During planning in the UI map screen, assign a steerpoint for each target in subsequent order— i.e., 5-6-7-8 for 4 targets.
2. When in range of the targets (assuming they are all in the same area, otherwise this will not work) with the first target steerpoint chosen and cursor-zero (no slewing necessary), releasing the first JDAM/SDB will send it towards the first target.
3. Quickly choose next steerpoint.
4. Release a second JDAM/SDB. Repeat step 3 for the remaining bombs.Following this procedure (which is real for the F-16) will let you use JDAMs or SDBs as a pre-planned GPS guided weapon and drop many in one pass. Note that since the LAR is flexible and assuming flight conditions allow, targeting four different targets in one pass by slewing the TGP between drops is possible."
Does the above mean:-
a) You can assign targets to steerpoints but the steerpoint do not actually relocate to the target positions.
b) When you select an assigned steerpoint in flight, the coords of the target associated with that steerpoint are fed into the JDAM. Release the JDAM and it will fly to the target.
c) Or, you could simply select each target by slewing to it in the TGP and TMS Up to lock it and the JDAM will fly to that target.If the above is true, why do I need to enter the target coordinates in the DEST page for the JDAM? I could just assign them at the RECON page.
It’s kind of confusing.
AFAIK
(a): I am not sure but I think it does relocate the navigational point.
(b): Yes.
: Yes, but it’s a slower release and I sometimes have trouble with that and the bombs don’t hit. I don’t know what I am doing wrong, it may be a cursor zero issue or something.You would always prefer to use the RECON page to do set your points. I usually start at Steerpoint 99 and work my way down rather than messing with the navigational point because if I am going to ripple JDAMS I want to just go to 99, pickle, 98, pickle, 97 pickle, etc. There are two options there to set a target steerpoint, one is [STPTs] and the other is [WPN TGTs] as I recall. As I understand it, you just use the default [STPTs] for most weapons. I think Spice bombs use [WPN TGTs].
I would only use the DEST page in multiplayer or for offset aim points. So say for some reason your target is a no go and some other person can send you the Latitude and Longitude, you could use the DEST page to enter in the coordinates as you fly to the release area. If the other person is in your flight and it’s 5 or less targets it’s probably easier for him to – one at a time – MARK those targets, MSEL to make it his current STPT, make sure the HSD is the SOI, and then I think its CommsRight to send the target information to you. Those becomes your STPT 71, 72, etc. IIRC.
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- you can only get an area lock with the TGP using JDAMs - not a point lock - so what looks like the centre of the target on the TGP from 15 mile away when you release may not be the centre of the target when you overfly … it still might be the Curser but without point lock you may well miss.
Hope this helps
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- you can only get an area lock with the TGP using JDAMs - not a point lock - so what looks like the centre of the target on the TGP from 15 mile away when you release may not be the centre of the target when you overfly … it still might be the Curser but without point lock you may well miss.
Hope this helps
Are you sure about this Steve?
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clarification - you cant get a point lock using TGP on irregular objects such as bridges … Cheers Malc.
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AFAIK
You would always prefer to use the RECON page to do set your points. I usually start at Steerpoint 99 and work my way down rather than messing with the navigational point because if I am going to ripple JDAMS I want to just go to 99, pickle, 98, pickle, 97 pickle, etc. There are two options there to set a target steerpoint, one is [STPTs] and the other is [WPN TGTs] as I recall. As I understand it, you just use the default [STPTs] for most weapons. I think Spice bombs use [WPN TGTs].
QUOTE]
When using the Recon page, which is the diference between selecting target steerpoints or weapon steerpoints ?
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AFAIK
You would always prefer to use the RECON page to do set your points. I usually start at Steerpoint 99 and work my way down rather than messing with the navigational point because if I am going to ripple JDAMS I want to just go to 99, pickle, 98, pickle, 97 pickle, etc. There are two options there to set a target steerpoint, one is [STPTs] and the other is [WPN TGTs] as I recall. As I understand it, you just use the default [STPTs] for most weapons. I think Spice bombs use [WPN TGTs].
QUOTE]
When using the Recon page, which is the diference between selecting target steerpoints or weapon steerpoints ?
Weapon Steerpoints (WPN) are only for certain ordinance - like the SPICE bombs ( I don’t know if there are any other weapons that work like that too). The way they work is that instead of using one or more of the plane’s steerpoints for weapon target coordinates, the coordinates are fed directly to the weapon, giving you 100 (99?) completely free slots instead of the usual "minus flightplan steerpoints, minus PPTs, etc.
Cheers!
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When using the Recon page, which is the diference between selecting target steerpoints or weapon steerpoints ?
I have never used WPN TGTs because I haven’t flown Israeli aircraft and AFAIK those steerpoints are only used for spice bombs at the moment? So I don’t know if they are utilized differently or how to select them during flight. I SUSPECT they don’t show up on the DED but they do show up on the WPN page?
Also, as I understand it – this may very well be wrong – you have 100 regular STPTS and 100 WPN TGT steerpoints.
And here is my breakdown of regular steerpoints, hopefully someone will interject with corrections:
All regular steerpoints show up as STPT in the HUD and DED. There are several Steerpoint (STPT) subcategories:
1. Flightplan/Navigational Line enabled steerpoints #1-24 per flight (these CAN but don’t always have navigational lines in 2D and the HSD) (herein only NPT for navigation point). An NPT may have a navigational line and no target; a navigational line with a specified target; or no navigational line target and is only a specified target;
2. Bullseye is #25;
3. In flight self-made MARK points #26-30;
4. Line steerpoints #31-50;
5. Preplanned Threats #56-70;
6. In flight received from other MARK points #71-80;
7. Available target steerpoints (no navigational line) #81-99. -
If you attempt to record coordinate values as steerpoint in the recon page onto the DTC and those coordinates are not displayed as you expect when you look in the DED then there is something wrong with your recon-to-DTC-to-jet pipeline process.
#0A just checking what my DTC says is for waypoint 6 before I begin. I’m playing with the TE TR433_10_GPbombs
target_5=0.000000, 0.000000, 0.000000, -1, Not set#0B before I mess with precision steers I’m just going to save the flight plan and record what the DTC file reads for steer 6
target_5=1202112.625000, 2136907.000000, -15000.000000, 17, Not set#1 is of course picking out the object in the recon screen, selecting a steerpoint number to assign it to, and click the assign the button. This stage is checked by seeing that an object description is tied to a particular number in the rotary. I’ve chosen the top entry of the KOTAR range objective as my precision location for stp 6, 37* 07.839’ 130* 20.674’ 2854 ft. “RNG - Vertic Tgt1” and pressed the accept button. To double check this I’m going to the Data Cartridge dialog and scrolling to 6 on the Target Steerpoints rotary. It shows KOTAR Range RNG - Vertic Tgt1 - 37^07.839’ / 130^20.674’" as output. For fun I check the DTC file
target_5=1202112.625000, 2136907.000000, -15000.000000, 17, Not set
No change! This is an important thing to note. The DTC file isn’t written until I press the SAVE button. These assignments are stored in a buffer which will be written on next DTC write but the assignments themselves do not prompt a write.#2 Press SAVE button and check DTC file again
target_5=1200467.625000, 2138581.250000, -2854.000000, 17, KOTAR Range RNG - Vertic Tgt1#3 Committing to fly. I check both the DEST and STPT DED pages and it shows this precision coordinate. That’s not necessarily the case, especially for a ramp start. The .ini file doesn’t always get loaded automatically. I think the defaults are to auto load on all joins except ramp but those options can be changed. It’s also important to realize that there is the pilot .ini file and the TE .ini file and even in the absence of either some flight plan data will be loaded into the jet on commit (leftover from Falcon 4.0 where there was no such thing as an .ini). For example I deleted the TE ini and my callsign ini and I still got a flight plan in jet on commit despite no ini-based manner for the jet to know the flight plan.
In cockpit both my STPT and DEST numbers matched planned. But I decided to test what editing them in flight does. I switched to AG and FZ GM FCR so I could get a number on the FCR MFD. Unsurprisingly it starts the same as planned. If I edit a coordinate on the DEST page the FZ numbers on the MFD update, DEST numbers change to match, the cursor moves, and the CZ OSB label is not highlighted. However if I edit the DEST coordinate the GM FZ numbers don’t change, the cursor does not move, CZ highlights, and STPT numbers do not change.
Those are some subtle differences but significant. If I click the CZ to zero the deltas then the STPT and DEST numbers match (STPT changes to match DEST). The practical effect is altering STPT is that you are updating the post-delta position (which zeros any deltas previous and also updates the reference position to match) and if you alter the DEST numbers you are only editing the reference position (cursor position unaffected).
To diagnose issues, check in order:
1. DTC dialog
2. .ini file
3. DED pages