CCRP release parameters
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I dose not change the point that the release command is terminated. The question is why. If he and repro, this behaviour,we have a starting point.
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Different Rel Angle settings
All the REL ANG setting does is change the loft HUD cues. The actual CCRP release math is unaffected. If you were to fly the exact same physical trajectory the REL ANG setting wouldn’t change anything. However if you’re flying the symbols then different REL ANG values will prompt your maneuver at a different time with obvious consequences.
No, you should strive to pull up when the computer tells you.
Sadly if lofts are done by the book and symbols, the maneuver will be too early kinematically. It’s a fault of BMS and requires a compensation by the user.
The assumptions are MIL selected (who wants to make a hot target for an IR SAM?), 4G in 2s (good tip to think of G coming on by the end of flash), and held through release. The bomb is supposed to come off while the G meter says ~4 and the nose is rating quite fast. The post-release recovery is to continue the pitch rate and slice back nose low.
This thing where BMS pilots do a hard pull up to a set angle and then unloaded to climb in a straight line to release is not how it’s done. On YouTube at least 90% of examples get it wrong. These 2 videos are better in that the plane isn’t unloaded to 1G or less but it certainly isn’t a constant 4. Had the WR button been held when the TTRN said 0:00 it probably would have come off. Notice how the time to loft shows 0:00 and the pilot waits 3-5 seconds? That’s a fudge factor. BMS just needs a bigger fudge factor. If he would have initiated his pull up at exactly 0:00 (as you’re supposed to) the first time he would blow through 45° with no release every time because the symbols activate too early.
I found that if you substitute a different REL ANG (<45) you can get the timers and symbols to indicate appropriately for an angle larger than the one you entered. E.g. if you put in REL ANG 15 you might get a release at 22 and if you put in 22 you might get a release at 40. With some trial and error you could develop a rule of thumb. I can say that don’t chase the last 5 degrees or so and consider a release at 40 to be absolutely as good as one at 45. The difference in ballistic range between those two angles is negligible. Since LAT is primarily to minimize time exposed and altitude gained losing 500’ of standoff is no concern. Getting releases in the 40-45 range is all risk and no reward. I would say 35-40 is the sweet spot.
You should find the CCRP much more eager to release at loft angles <40 degrees and with a constant and relatively high load factor throughout the maneuver provided the maneuver was started close enough to the target.
I feel a little betrayed that lofting delivery was never mentioned in post #1. Lofting is a specific case that has a history of problems in BMS. Is this also happening with level releases?
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In the first video, you pull up a little bit late and it looks like the release cue never actually reaches the FPM, thus not completing the solution. Pull up 4-5G as soon as the reticle stops flashing.
FWIW, the jet is continuously calculating a release solution, so once he’s inside of max loft range he’s “a little bit late” ONLY in terms of a maximum distance loft. The bombs will come off sooner (a lower nose high pitch) the closer you get to the target. Afterall, if he simply held down the pickle button and flew straight and level directly over the target the bombs should release at some point in space. That would be a valid test for the OP. Attempt to fly level CCRP deliveries in his Campaign.
As an aside, I suspect it’s just a simism, but in his TE video I heard snakeye at release. Maybe BMS defaults to calling all Mk-82s snakeye upon release?
EDIT: Frederf makes a great post, it’s what I was thinking that guys should experiment with just 30-40 degree pullup.
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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:
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 … 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 … 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 hadn’t 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 won’t 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. Everyone’s system and experience of this would probably be different, but for me only pressing the button a few seconds before release isn’t 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.
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Bug #1 - the wind is coming from your left in that screenshot. You are tracking 025°, with wind coming from 332°. The azimuth cue is biased to the left, into the wind, with the target to the right, downwind of the solution.
Bug #2 is a longstanding issue, which is why BMS wings train to press the pickle a couple seconds before solution, instead of the prototypical pickle to consent, unpickle if situation changes.
As far as the long/short head/tail wind stuff for bug #1, that might merit further investigation IMO.
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FWIW, I can remember all the way back to the Superpak/FF days as the cue hit the FPM, release the pickle and instantly consent again. Just because of this situation. Don’t know if this is still the same ole gremlin. I’ve just carried it with me through each iteration of F4. Bombs always come off… shrugs. This is for CCRP. With CCIP I’ve never had to re-consent.
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No, 25 in the HUD is 250°, not 025°.
mmm. And the FPM is displaced left of the gun cross, not right of it. That does suggest such an issue as you propose.
EDIT: same as another issue in the past, the gun cross is aligned but it should be the FPM instead.
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I haven’t followed this thread closely, but have been dropping in from time to time. Sorry if this has been said and I missed it. I have never been able to get reliable releases by tossing.
I saw a post in here earlier with a diagram showing that the toss is supposed to be done as part of an Immelman. So I watched Supanova’s video and he did the hold in climb too, but said you wait to a count of three before pulling up. So I tried it during the loop at RA 30. No joy. I kept at it and at it and fine tuning it and I just finally got three release in a row by waiting for a count of 4 and using a release angle of 45. CAS somewhere between 490 and 520 I’d guess. And I just pulled a smooth loop, and never worried about holding the release angle pitch. I was pressing and holding the pickle button down at the end of my count of 4. Pulling about 4Gs and the bombs come off each time under those parameters. This was a TE and l didn’t check wind.
I also noticed with Paveways in the 89 campaign that they were coming off the rail on me early and not making it to target. On a straight and level CCRP I do wait until the cue touches the top of the FPM fin, but in the 89 campaign (I don’t know if it happens elsewhere) like I said, the bombs were releasing early. So for LGBs I’ve been pickling the instant the cue bounces back up from the FPM and haven’t missed once with that change.
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As an aside, I suspect it’s just a simism, but in his TE video I heard snakeye at release. Maybe BMS defaults to calling all Mk-82s snakeye upon release?
Yeah, that’s the AI weapon item name for dumb bombs. BDU-33s have a mike short squelch sound instead. The Falcon 4.0 voice files are a bit limited. There is a “bombs away” voice sample; I wonder if that could be made the one for Mk-80 series.
That wind issue warrants more eyes. That’s clearly a wind out of NNW while flying W. It’s interesting to see that the loft maneuver cues are affected by wind. I would investigate the loft maneuver cueing in the zero wind case as well as the strong wind case. My memory is that the cue was optimistic in the zero wind situation but if the range at maneuver start is being indicated as you say that would be another layer of error.
Thinking aloud:
1. The jet probably is predicting winds at different levels based on current INS wind drift. The A-10 for example interpolates the current wind at altitude down to -1000’ being zero wind. I bet the F-16 does similar. If it thinks wind is 20kt at 9kft it should think wind is 10kt at 4kft, 2kt at 0ft, 0kt at -1kft. If the sim wind is a steady X kt at every altitude that might not match the ballistic wind model assumption. Or maybe I’m over analyzing.
2. I’m interested in using manual release to enforce bomb separation at 45 degrees based on the loft cueing and the normal schedule (4G in 2s, MIL) to see where the bombs land flown on precomputed numbers. Basically bomb WWII style using the computed maneuver range to see the magnitude of the error if any.
3. Use of BDU-33 for smoke markers to check impact locations.
4. How well the current loft maneuver cueing corresponds to the sim kinematics based on various entry speeds. Higher speeds would mean larger radii of pull up and more downrange offset for a given G. Your 500-550 range sounds correct though.
// If set then winds will change direction and strength with altitude. This makes dumb bombs very inaccurate from high level, but LGBs are unaffected.
set g_bEnableWindsAloft 0This is an old config line which I’m not sure applies to 4.33u3 or if it’ll change anything with this situation.
I’ll double up on your WR campaign fail test and see if my WR button unsticks while held in campaign and TE.
EDIT: I did the manual release at the same distance as CCRP wanted me to start the loft and came up about 5000’ short. I’d have to do it half a dozen times consistently to have much confidence in that particular distance but definitely short by a bunch in any case (no wind).
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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:
One last run was made against a different target, rippled off 8 bombs at 75 feet spacing, from an altitude of 15000ASL:
Not conclusive, certainly not scientific, but enough to make me happy that my bombs are pretty close in most instances when I fly the numbers.
Remember, all of this was at 30 frames per seconds, instead of the usual; 80 or so I get in TE.
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I consistently encounter the weapon release bug in campaign. Flying at 20,000 FT, 350K, level, CCRP release GBU 24. Holding down the WR with 2-4 seconds until cue hits the FPM, bombs consistently fail to release until a second button press.
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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 don’t 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 don’t 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 don’t 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 you’re calling me a liar?
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Maybe it’s the wind. When I come in at 550 knots at 4,000’ 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 it’s the wind. When I come in at 550 knots at 4,000’ 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 I’m 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). I’m 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 should’ve 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, 200’ RI, for a 35 deg loft (video shows loft of ~33 degs) you’re looking at at a release altitude of ~1600’ (video shows ~2000’), a target to PUP range of 4.0 and a release range of 3.1. The video is showing ranges outside of this… However, I would say it’s close enough.
What I’m 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 I’m 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 we’ll use M904/M905s and set an AD of 4.8 seconds. 4 secs +/- 20% tolerance.
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Shouldn’t 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. That’s pretty good energy retention. I didn’t record my altitude gained which is a good crosscheck value. Even if I was constant airspeed I’m sure it would be short.
@F32S. That’s 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. It’s pretty simple what I’m looking at.
This is all semi simple vacuum trajectory math that doesn’t 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. I’m seeing 6.5nm loft cue range and if you shorten that by 0.707 for a 45 degree pull up that’s 4.5955nm which is shockingly accurate to your account of maneuver range.
On another topic you mention the PUAC or staple or whatever it’s called. In BMS there is no vertical steering symbol for toss bombing. LADD should have it but it’s 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 isn’t 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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Shouldn’t 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. That’s pretty good energy retention. I didn’t record my altitude gained which is a good crosscheck value. Even if I was constant airspeed I’m sure it would be short.
@F32S. That’s 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. It’s pretty simple what I’m looking at.
This is all semi simple vacuum trajectory math that doesn’t 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. I’m seeing 6.5nm loft cue range and if you shorten that by 0.707 for a 45 degree pull up that’s 4.5955nm which is shockingly accurate to your account of maneuver range.
On another topic you mention the PUAC or staple or whatever it’s called. In BMS there is no vertical steering symbol for toss bombing. LADD should have it but it’s 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 isn’t 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 it’s extremely hot out on a pop attack we’ll tap min burner when popping 30 degs. nose high. This is only because we have a TR (training rule) that doesn’t 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, it’s just the vertical line. You want your FPM to be as close to perfect flying up the line because that’s 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 you’ve received that, the staple now represents ground clobber.
To fly a loft, time until pull-up will be zero, you’ll 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.