CCRP release parameters
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Just out of interest, I did half a dozen low alt lofted CCRP (with 1 x Controlled Flight into Terrain to boot ) at KOTAR. INS wind was 335 at 13 kts. Ground speed was 500KGS, release angle 30 degrees, I would go gate when the reticle flashes and look for 4-5G pullup, from various headings. The telling factor, I limited frame rate to 30 FPS (a handy side effect FRAPS gives), and here are the results:
Was that a head or tail wind situation? Can you do a no-wind version? What distance from the target did the 0:00 on the TTPU clock correspond to? I donāt think anyone here to calling into question the accuracy of the CCRP release but more the toss maneuver cues and the ability to actually get a release.
A 4-5G pull up started at 0:00 and release by 30 degrees? I call B.S. on that.
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CaptCanada:
I thinnk your main problem was nailed by Blu3wolf. You donāt pickle as the cue hits, what you do is hold the pickle button down and fly through the cue. Once the bomb drops off then and only then do you release the pickle button.
Also, keep in mind on any drop you donāt want to be zigging and zagging. Nice and easy corrections are best. (If ONLY I followed my own advice LOL). One more pointer, if you have pulled too many Gs on your way to the target your bombs might malfunction or just hang on the rail. I keep hearing to try to keep it under 5.5Gs until all your bombs are gone.
Correct. Pickle and hold until the solution cue (horizontal bar on the vertical steering bar) moves up. When it reaches the FPM, the FPM will flash and the bombs will release.
Correct for most heavyweights. 5.5 Gs.
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A 4-5G pull up started at 0:00 and release by 30 degrees? I call B.S. on that.
So youāre calling me a liar?
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Maybe itās the wind. When I come in at 550 knots at 4,000ā MSL at KOTOR with a zero wind environment the CCRP tells me to initiate my pull up at 6.5nm slant. When I select MIL and get to 4G in 2s I will blow past both 30 and 45 degrees without a solution and release.
Do you get the same?
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Maybe itās the wind. When I come in at 550 knots at 4,000ā MSL at KOTOR with a zero wind environment the CCRP tells me to initiate my pull up at 6.5nm slant. When I select MIL and get to 4G in 2s I will blow past both 30 and 45 degrees without a solution and release.
Do you get the same?
Try going full AB and hold some speed, see what happens.
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Based on what Iām seeing in the first video, the solution cue never touched the FPM AND the pickle button was not being held down during the loft (as this has been stated). Iām not sure what the winds were in the videos but the ballistics look to be a little off. Based on when the bombs did release, the jet shouldāve been a little closer to the target and at a lower altitude. For a GBU-12 (yes, will differ from a Mk82 slightly), at 550 KTAS, 200ā RI, for a 35 deg loft (video shows loft of ~33 degs) youāre looking at at a release altitude of ~1600ā (video shows ~2000ā), a target to PUP range of 4.0 and a release range of 3.1. The video is showing ranges outside of thisā¦ However, I would say itās close enough.
What Iām trying to figure out is why for a 45 deg. loft, the symbology is showing to begin the loft at 5.5 NM, but it should be more like 4.6 NM (again Iām not sure what the winds are, but should not be a mile off). The pilot did not fly the loft maneuver correctly for the 45 degs. he has entered. Which is why the bombs release at ~33 degs and not 45. You should just sit the FPM on the staple and fly it up the vertical steering line to the solution cue. This would have brought him closer to the desired parameters. Why does this matter? Because depending on what the target is, I need to meet certain impact angles and velocity to get the DWE.
Also, usually for Mk82s weāll use M904/M905s and set an AD of 4.8 seconds. 4 secs +/- 20% tolerance.
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Shouldnāt have to select MAXAB for loft. The assumption built into the design is MIL but it makes sense that higher power improves the kinematic situation. At 550 and MIL I decay airspeed to 500 by 45 deg. Thatās pretty good energy retention. I didnāt record my altitude gained which is a good crosscheck value. Even if I was constant airspeed Iām sure it would be short.
@F32S. Thatās more or less what I see as well, an early maneuver cueing on the order of 1nm. I went so far as to see if I could find the actual math line in the F4 source code to find out how the loft range is calculated. Maybe BMS has altered the code since that branch. Itās pretty simple what Iām looking at.
This is all semi simple vacuum trajectory math that doesnāt have any explicit compensation for speed decay. I think the airGroundMaxRange value is the potential weak point. The process goes like this:
0. Calculate loft ground range on assumed max or entered angle.
1. Calculate radius of 4G turn V^2/4G.
2. Add to the predicted loft ground range an extra projection due to the turn.
3. When curRange = airGroundMaxRange, tmpTIme = 0, do the maneuver.I suspect that airGroundMaxRange is being assumed to be the horizontal velocity component times the predicted TOF without considering that that velocity component will be severely reduced by the pull up. Iām seeing 6.5nm loft cue range and if you shorten that by 0.707 for a 45 degree pull up thatās 4.5955nm which is shockingly accurate to your account of maneuver range.
On another topic you mention the PUAC or staple or whatever itās called. In BMS there is no vertical steering symbol for toss bombing. LADD should have it but itās not fleshed out. I forget if regular CCRP should have that third mechanization for that symbol (the first two being fuze arming and ground clobber).
On a third topic the 10nm range scale is goofy as the vertical DLZ-style staple isnāt putting the top and bottom marks according to their indicated functions of max or desired loft angle (top) and I think the level solution (bottom). In BMS the top mark is level solution and the bottom mark represents some steep dive.
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Shouldnāt have to select MAXAB for loft. The assumption built into the design is MIL but it makes sense that higher power improves the kinematic situation. At 550 and MIL I decay airspeed to 500 by 45 deg. Thatās pretty good energy retention. I didnāt record my altitude gained which is a good crosscheck value. Even if I was constant airspeed Iām sure it would be short.
@F32S. Thatās more or less what I see as well, an early maneuver cueing on the order of 1nm. I went so far as to see if I could find the actual math line in the F4 source code to find out how the loft range is calculated. Maybe BMS has altered the code since that branch. Itās pretty simple what Iām looking at.
This is all semi simple vacuum trajectory math that doesnāt have any explicit compensation for speed decay. I think the airGroundMaxRange value is the potential weak point. The process goes like this:
0. Calculate loft ground range on assumed max or entered angle.
1. Calculate radius of 4G turn V^2/4G.
2. Add to the predicted loft ground range an extra projection due to the turn.
3. When curRange = airGroundMaxRange, tmpTIme = 0, do the maneuver.I suspect that airGroundMaxRange is being assumed to be the horizontal velocity component times the predicted TOF without considering that that velocity component will be severely reduced by the pull up. Iām seeing 6.5nm loft cue range and if you shorten that by 0.707 for a 45 degree pull up thatās 4.5955nm which is shockingly accurate to your account of maneuver range.
On another topic you mention the PUAC or staple or whatever itās called. In BMS there is no vertical steering symbol for toss bombing. LADD should have it but itās not fleshed out. I forget if regular CCRP should have that third mechanization for that symbol (the first two being fuze arming and ground clobber).
On a third topic the 10nm range scale is goofy as the vertical DLZ-style staple isnāt putting the top and bottom marks according to their indicated functions of max or desired loft angle (top) and I think the level solution (bottom). In BMS the top mark is level solution and the bottom mark represents some steep dive.
Yes AB should definitely not be needed. Sometimes if itās extremely hot out on a pop attack weāll tap min burner when popping 30 degs. nose high. This is only because we have a TR (training rule) that doesnāt allow you to go below 350 knots in a pop attack.
Nice math, pretty much matches what the T.O. says.
There is a vertical steering line. Watch the videos again, itās just the vertical line. You want your FPM to be as close to perfect flying up the line because thatās what gives you a better bomb. When running in if the FPM falls below the staple (or staple rises above the FPM depending on how you look at it) you will get a LOW mnemonic for fuzing. This is based on the arming delay. After youāve received that, the staple now represents ground clobber.
To fly a loft, time until pull-up will be zero, youāll just sit the FPM on the PUAC as best you can while flying the FPM up the line. If you do this perfectly, the FPM should hit the solution cue at the loft angle that you have set.
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FoxThree, worth noting that for BMS Mk82s and GBU-12s share ballistics.
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Yeah I know the azimuth steering line (ASL) for lateral steering. I thought you were mentioning a pitch steering cue for the pull up. In LADD (real) the fuze arm/clobber-looking cue actually scrolls up the center of the HUD in an upward direction to help with pitch steering.
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Yes AB should definitely not be needed. Sometimes if itās extremely hot out on a pop attack weāll tap min burner when popping 30 degs. nose high. This is only because we have a TR (training rule) that doesnāt allow you to go below 350 knots in a pop attack.
Thanks for the heads-up. My personal experience shows AB not strictly needed, but an adherence to the numbers is almost vital. Lazy pull-ups and the like will often result in a failure to meet the release requirements, but if you are deliberate the bombs will usually drop. Going full AB makes the whole process a lot less prone to error, however I do appreciate there are times when full AB is undesirable too.
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Thanks for the heads-up. My personal experience shows AB not strictly needed, but an adherence to the numbers is almost vital. Lazy pull-ups and the like will often result in a failure to meet the release requirements, but if you are deliberate the bombs will usually drop. Going full AB makes the whole process a lot less prone to error, however I do appreciate there are times when full AB is undesirable too.
A strict adherence to the numbers for BMS will invariable result in a failure to meet the programmed release, and frequently a failure to release at all.
Any AB means not adhering to the numbers, so there is that.
The state of BMS means trying to perform a loft by the numbers is a waste of effort, effort that would be better spent lobbying the devs to fix the loft code.
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A strict adherence to the numbers for BMS will invariable result in a failure to meet the programmed release, and frequently a failure to release at all.
Any AB means not adhering to the numbers, so there is that.
The state of BMS means trying to perform a loft by the numbers is a waste of effort, effort that would be better spent lobbying the devs to fix the loft code.
Okay, Iām uninstalling nowā¦ my life is at an end.
- PS - Ice, Iām still having it on Tuesday as discussed.
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Id add the /sarcasm tag to my signature block, but seeing as the sig is displayed maybe once per 40 posts, it wouldnt helpā¦
Perks of a text only communique. In any event, a ādeliberateā pull up on the numbers will invariably result in no solution - unless initiated late, i.e. after max range is passed.
Both Frederf and I have had the discussion about CCRP lofting several timesā¦ with testing. And the consensus was that unless you delay your pull until well inside the range indicated, you will pull past 45 with no solution.
So there is a frustration there I suspect, borne of evidently differing personal experience.
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After doing more testing tonight, I think we are the victims of 2 separate bugs.
Bug #1
I believe that the CCRP calculation has the wind direction reversed. In my campaign save file (the one from the video above) I played with invulnerability and unlimited fuel so I could experiment, and discovered that if I attacked from the other direction (with a tailwind) using the same speed and pulled up when the loft cue appeared, the release cue moved smartly down the line and hit the flight path marker no problem. When I did it with a headwind, the release cue moved very slowly down the line and barely touched the flight path marker before moving back upwards. I think it is safe to say that it never reached the centre of the flight path marker, which would be required to trigger a release.
Also, look at this screenshot from testing tonight:
http://i.imgur.com/uuq6uax.jpg
The wind is coming from my right, but the steering line is to the left (downwind) of the target. Surely it should be upwind of the target.
To be sure, I added an 80 knot wind in my test TE (the max it would allow me to add). In the 3D world the DED showed the wind speed varying from about 65 to 75 knots. I noticed that flying on the deck at full mil power (roughly 550 KCAS) with a tailwind, the last flashing circle disappeared at around 5.0 NM from the target. With a headwind, it was around 5.6 NM from the target. This is backwards!! With a headwind you must be closer to the target.
I think that in a campaign if you have a decent headwind and pull up as soon as you see the loft cue, the release cue will not actually make it all the way to the centre of the flight path marker because you pulled up too early.
Another indication that the wind direction is reversed in the calculation ā¦ in my TE with the strong winds, when dropping with a headwind the bombs landed very short, but with a tailwind they landed very long ā¦ but in both directions they seemed to land in the same spot (based on the black marks on the ground).
(For the devs if you are reading this: I bet CCIP has the same issue)
Bug #2
Thank you whoever pointed out that the SMS shows REL or RDY based on whether the pickle button is pressed. I hadnāt noticed this before. During a couple of tests tonight I looked down and saw RDY even though I still had the pickle button down. I think this may have happened in the campaign video I posted, since I know I had the pickle button down well past the time when the release cue was near the flight path marker.
I did some tests to see how long I could hold the pickle button down before it flipped to RDY. It happened anywhere from 1 to 20 odd seconds. I think 25 was the longest I made it. This is in campaign mode. When I went back to the TE to try this, I made it to 2 minutes before I gave up. In other words, holding the pickle button down is perfect in the TE, and problematic in the campaign.
Pushing the pickle button as close as possible to the release point is good advice, because it seems to be quite unreliable. Based on my testing there is no specific safe time that it can be counted on to trigger a release. I think that for CCRP drops it is wise to have the SMS screen up and glance regularly at the REL/RDY notation to make sure it is registering that the button is still down.
It looks like the logic in the sim is that once the button appears to be released, it wonāt register another press until the physical button is released. Can this logic be changed for CCRP mode? I am assuming that the code is polling the state of the buttons every frame. Surely if the button appears to be down and the system is in CCRP mode, then treat it as down.
Anyway, I think I have been bitten by the first bug occasionally in my campaign, (because I have noticed the release cue having a tough time making it to the flight path marker a few times), but a lot by the second bug. All CCRP drops (level or lofting) would be affected by the second bug. Everyoneās system and experience of this would probably be different, but for me only pressing the button a few seconds before release isnāt enough to guarantee a drop, as the status can flip to RDY on my system in as little as a second in campaign mode.
Hopefully someone from the BMS team notices this thread and can check the relevant code.
So I tested the first ābugā in the jet a couple days ago and this is how it worked. One thing I did notice, however, is that the steering line should be lined up with the TD container when the FPM is centered on the steering line no matter what the winds are. When you have the FPM displaced left of the steering line, the steering line is left of the TD container. When you have the FPM displaced right of the steering line, the steering line is right of the TD container. Again, no matter what the winds are.
I would have to do some more testing and think about it, but this means the bomb is being dropped in a crab (angle between FPM and boresight cross) instead of dropping it offset from the target (like the poster seems to think). Ideally you want the bomb to have as close to zero AOA when it hits. Smart weapons are able to do this depending on what the weapon is, dumb bombs not so much.
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So I tested the first ābugā in the jet a couple days ago and this is how it worked. One thing I did notice, however, is that the steering line should be lined up with the TD container when the FPM is centered on the steering line no matter what the winds are. When you have the FPM displaced left of the steering line, the steering line is left of the TD container. When you have the FPM displaced right of the steering line, the steering line is right of the TD container.
Juvat?
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Got a problem releasing MK.82 LDGP using CCRP level flight (not loft) . . . 20000ft, 400knots, locked ground target, arm switch on,steady flight, watching the cue . . . holding the pickle before the second cue hit the FPM . . . But the bombās r not released
Tried this 3 time in the campaign.i read in this discussion that the wind can be one of the problems . . . i had 14kntos headwind on the target area.
any suggestions ?
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Shooting in the dark here, but:
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donāt hold the pickle too long before. 2-3 seconds should suffice. Iāve heard of weapons not coming off if you pickle too early.
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Make sure you havenāt damaged your bombs earlier by going too fast/ flying too aggressive. <mach 1=āā and=āā <=āā 5gās=āā should=āā do=āā it.<br=āā>3) make sure youāre not over mach 0.95 when trying to release. Whatās the mach number at 400kn @ 20000ft? I donāt think itās over mach oneā¦
You probably know these already, but I figure maybe you missed something or forgot.
Cheers!</mach>
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Shooting in the dark here, but:
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donāt hold the pickle too long before. 2-3 seconds should suffice. Iāve heard of weapons not coming off if you pickle too early.
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Make sure you havenāt damaged your bombs earlier by going too fast/ flying too aggressive. <mach 1=āā and=āā <=āā 5gās=āā should=āā do=āā it.<br=āā>3) make sure youāre not over mach 0.95 when trying to release. Whatās the mach number at 400kn @ 20000ft? I donāt think itās over mach oneā¦
You probably know these already, but I figure maybe you missed something or forgot.
Cheers!</mach>
thank for the tips
I pressed the pickle well over the 2-3 seconds heheh . . . i will try your suggestionās in my next campaign mission.
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