Low altitude toss in 4.33 U1
this was always one of my favorite attack profiles, especially against high threat systems like SA-6+ or patriots; however i’m having a little bit of trouble in 4.33 U1 with the updated JDAMs; for whatever reason the default profile seems to insist on what seems like an unnecessarily high climb before release. as far as i know, the kinetics of the JDAM itself haven’t changed that much. does it have to do with the impact AZ and impact angle/speed, and if so, can anyone tell me what the “ideal” values are (or something close?)
i do like the new JDAMs as they are far easier to use than the old hackey 999 impact spacing method, however this is the one snag. any help appreciated.
Scrim last edited by
As always, a fairly detailed documentation of your deliveries would be of great help in understanding wherein the issue lies.
Frederf last edited by
Assuming you want maximum toss range you would not set a desired azimuth (which is also the default setting) and/or terminal angle. The JDAM is able to be released when inside the LAR and the LAR is calculated from current flight conditions. The solution is to adopt flight conditions of the airplane that places the F-16 in the LAR for the given target location. The maneuver would be performed, the LAR grows, and the weapon release button is held.
When released level from moderate altitude it will fly a non-ballistic trajectory that significantly increases the lateral range vs. dumb bombs. Because the JDAM seeks a calculated path it is in the pilot’s best interest to loft the bomb exactly along this path. The bomb will maneuver to its calculated trajectory regardless of release condition with corresponding energy loss due to the steering required to return to its internally-calculated trajectory. Loft release trajectories may even reduce the total range of the weapon compared to level release.
For SA-6 I would recommend a maximum energy high altitude delivery as the standoff range should exceed the SAM’s range suitably. Patriot is a more difficult problem.
after a little experimentation i’ve managed to get LAT to work, however is there ever any reason to do high altitude toss (angels 20+?) even assuming i am pushing on DNE (when the airframe starts groaning, near mach 1) the bomb seems to take a needlessly high course regardless of my release angle. i push up to the DNE border, get to the loft cue, pull up to release angle (20-45 degrees, doesn’t seem to matter almost at all) and wait for release cue. however pretty much regardless of release angle the bomb spends maybe 40% of the time 50-70 degrees nose up and then the rest of it’s flight almost totally nose down; it feels like it should be possible to get this thing released far earlier and have it fly a much more nose-to-horizon aspect, rather than the extremely weird extreme climb/extreme dive aspect it takes in total defiance of pretty much every IMP VEL and IMP ANG setting i give it.
the furthest i think i’ve gotten from the target is pushing 14~ nm and it was a level drop at mach 1~ at 40,000. is there some reason MAT and HAT never seem to breach this barrier, pretty much regardless of release angle etc(?)
i’ve figured out LAT, though i swear i used to be able to get more range out of this thing.
i think that might be because of the stricter overspeed on wingtanks and bombs in since 4.33, and not some aerodynamic change on the bombs themselves.
mostly this is a curiosity though; glide and jet-assisted is available for the most part, and if SAM is the problem you can always toss cluster over a hill at it until it goes away.
flyway last edited by
Agreeing with Frederf, JDAM bombs aren’t intended to be lofted… IMO.
Too heavy for that aircraft’s maneuver and also because of what Frederf described.
yeah fair enough, i might just be trying to drive nails with a screwdriver.
ajthenoob last edited by
Why not use standard clusters, or the MK series? They’re better for lofting especially the lower weight ones.
Blu3wolf last edited by
If you are tossing from a climb at fixed pitch you arent getting the max range you could be. Your max range toss occurs when you just barely hit the release angle required as the bombs come off, without slacking off the G. The anticipation cue is borked (technical term (not really)) in BMS, so you have to get closer than what it tells you.
Frederf last edited by
Impact angle is N/I in BMS or rather the setting is not adjustable via the MFD value, IIRC.
You might have gotten longer toss range with the older BMS JDAMs because they shot out like a rocket at 300 knots.
I tried a LAT with JDAM and oddly the anticipation cues for pull up while wrong (too early) for dumb bombs seem exactly right for JDAM. As soon as the circle started to flash I started a sedate pull up and the caret was in the middle of the LAR as I pitched through the 30-45 degree zone. I think my standoff was ~7nm. What you won’t see is any meaningful caret-and-LAR cues of when to initiate the maneuver.
The CCRP IAM mode seems fully compatible with LAT for JDAM at release conditions. I dare say the LAT anticipation cues are even accurate. I’m really not seeing a problem here.