GBU-12's guiding but not exploding.
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And what I’m saying is that setting AD has zero effect. I could be at 30k and not set AD and it will work correctly.
And if it does affect it in BMS then it’s not modeled correctly.
…if Arm Delay doesn’t affect DUDing, then it is NOT modeled correctly. If you’re at 500’ AGL and set a 10 sec delay, you ARE going to get a dud…unless you climb to an altitude where the TOF is > 10 sec before you release. Also, chances are that id you haven’t set an AD, then you haven’t programmed the fuse completely/correctly…and you will likely get a dud. IF BMS has it “right”…
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I know how to use them, I’ve been using them with great success in the Israeli theater, but I just switched to the Balkans, and now they’re duds, they guide, but no boom.
Where you waiting to see an explosion within the TGP page ? The LGB could have lost track and exploded elsewhere.
To figure out whets going, on, I would advise you to use the ACMI and review if your LGB is tracking correctly and also use the eternal weapons view to confirm if your LGB is a dud or not.
You can easily check if the arming delay is causing the fuss by observing if the fuse arming LOW mnemonic is adjacent to the FPM at the time of release.
If your LG is tracking but not exploding , you probably have a faultily fuse due to over G. -
…if Arm Delay doesn’t affect DUDing, then it is NOT modeled correctly. If you’re at 500’ AGL and set a 10 sec delay, you ARE going to get a dud…unless you climb to an altitude where the TOF is > 10 sec before you release. Also, chances are that id you haven’t set an AD, then you haven’t programmed the fuse completely/correctly…and you will likely get a dud. IF BMS has it “right”…
AD is not modelled correctly. In addition to PUAC / fuse arming cue, which works correctly, AD will physically alter the fuse settings as.
Ideally, fuse setting/arming should be set in the munitions UI, not via the AG Control page.
The AD settings in the AG control page should only affect the HUD PUAC/ fuse arming cue and the the actual fuse. -
…if Arm Delay doesn’t affect DUDing, then it is NOT modeled correctly. If you’re at 500’ AGL and set a 10 sec delay, you ARE going to get a dud…unless you climb to an altitude where the TOF is > 10 sec before you release. Also, chances are that id you haven’t set an AD, then you haven’t programmed the fuse completely/correctly…and you will likely get a dud. IF BMS has it “right”…
Arguing/debating a subject related to the F-16 with a real world F-16 pilot?
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It’s also kinda weird that if you have a nose fuze at 4s and a tail at 6s and you select NSTL it duds <6s TOF. If the front half of the bomb explodes the rear half tends to cave into peer pressure. Anyway whatever is shown on the SMS page is a perfect prediction of AD.
The possibilities to rule out are:
1. Bomb did explode but was not observed.
2. TOF was less than AD.
3. Fuze was damaged.
4. Fuze was not set.In the case of GBU-12 is the nose fuze required for guidance and rear fuze for detonation?
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AD will affect in BMS because we have a compromise. Since we cannot set the AD of the bomb outside (in the loadout screen for example) the code allow you to change it from the SMS, like a SMART RACK.
It’s not a bug, just a compromise. -
Stevie,
Just like I suspected and pointed out; BMS is not modeled correctly (but you know more I guess…). What you’re talking about is available on JDAMs only with a smart rack like a BRU-57 or BRU-61. With LGBs you’ll use the FMU-152 as well (and the -139) but these fuse settings are set on the ground usually via maintenance. Nothing in the SMS affects these bombs. Setting the AD only affects the PUAC and symbology as Leech lead on to.
Now, tell me what we set for AD for a GBU-12 with the newer seeker and then explain to me why… since you seem to know all about the GBU-12.
To the OP, sorry. But it appears you have to set an accurate AD for the bomb to work correctly. Realistically you’ll set 12 seconds for this. If you are not getting the LOW mnemonic in the HUD then the fuse will work correctly (again, this isn’t how it normally works).
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A GBU-12 should typically use a tail fuse, and depending on how it is rigged (or fuse type) there could be selectable AD times - 0, “short”, and/or “long”…again, depending on if the weapon is rigged as selectable for a mechanical fuse; interfaced for an E-fuse. Also - for a mech fuse rigged as selectable (or hard delayed), the crew needs to know from the ordnanceman which AD(s) the weapon is set for, and then select that in the cockpit so that the symbology matches the reality. If the crew selects the wrong AD he will get an early or late DUD cue…which again, is dependent on the release altitude - and fly the wrong profile.
So…there are/can be a number of ways a pilot can screw this up - no fuse selection, wrong fuse selection, wrong/mismatched AD selection, improper release parameters. At least, that’s the RL sitch; the seeker doesn’t matter…the fuse type does. So the real question is - what does BMS do with fusing? But I concur - you should have to set a proper/appropriate AD - AND fly an appropriate release profile - to get the weapon to function properly.
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Ive put occasional (rare) spells of failure to explode down to connection issues. Happens with various free-fall bombs and I’ve been extra careful in following flights that day to ensure I make no mistakes but if its
one of those days
on the mp server then same happens. Is this even possible ? Stock Korea. -
Where you waiting to see an explosion within the TGP page ? The LGB could have lost track and exploded elsewhere.
To figure out whets going, on, I would advise you to use the ACMI and review if your LGB is tracking correctly and also use the eternal weapons view to confirm if your LGB is a dud or not.
You can easily check if the arming delay is causing the fuss by observing if the fuse arming LOW mnemonic is adjacent to the FPM at the time of release.
If your LG is tracking but not exploding , you probably have a faultily fuse due to over G.I watched it on external view hit, and I had no warnings of an over-g, as I said, I was a bomb truck, no a-a happened, no dodging sams, nothing, simply took off, flew to were I needed to be, and dropped, I don’t see how that could cause an over-g, 747’s probably pull more g than I did….
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Did you make a another flight since? If not, please send me your DTC Fault log.
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A GBU-12 should typically use a tail fuse, and depending on how it is rigged (or fuse type) there could be selectable AD times - 0, “short”, and/or “long”…again, depending on if the weapon is rigged as selectable for a mechanical fuse; interfaced for an E-fuse. Also - for a mech fuse rigged as selectable (or hard delayed), the crew needs to know from the ordnanceman which AD(s) the weapon is set for, and then select that in the cockpit so that the symbology matches the reality. If the crew selects the wrong AD he will get an early or late DUD cue…which again, is dependent on the release altitude - and fly the wrong profile.
So…there are/can be a number of ways a pilot can screw this up - no fuse selection, wrong fuse selection, wrong/mismatched AD selection, improper release parameters. At least, that’s the RL sitch; the seeker doesn’t matter…the fuse type does. So the real question is - what does BMS do with fusing? But I concur - you should have to set a proper/appropriate AD - AND fly an appropriate release profile - to get the weapon to function properly.
Where are you getting this from?
The “short” and “long” is for the functional delay, which don’t even get used with LGBs, not the arming delay. With a GBU-12 you can sometimes see the arming delay during the walk around otherwise it’ll get written on the bomb body. Yes you’re right that you could set the AD in the SMS to what gets set by hand but that’s not what we do.
We set AD to 12 seconds: 8 seconds for guidance time + .8 seconds for CCG + 2.7 seconds for safe separation timing which gives you 11.5 seconds. We then round this up to 12 seconds.
When you speak of the pilot selecting a fuse you’re referring to him setting Nose, Tail, or NSTL. Depending on what fuses are used then yes you can DUD the bomb. However, the AD plays no part of this.
From this section of the 1-F-16CM-34-1-1:
With no JPF installed, any value between 0 and 99.99 seconds may be entered; the entered value will not be sent to the weapon, but will be used in computing the HUD LOW cue.
That is from the JDAM but the GP bombs work like that by default.
So in summary, what you set in the SMS does not get set to the bomb. It is only there to display an accurate LOW mnemonic to provide an indication to the pilot so he doesn’t DUD the bomb using the arming delay set by weapons on the ground. An inaccurate setting of NSTL will DUD the bomb, however.
Disclaimer: this is real world; BMS is different.
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Where are you getting this from?
The “short” and “long” is for the functional delay, which don’t even get used with LGBs, not the arming delay. With a GBU-12 you can sometimes see the arming delay during the walk around otherwise it’ll get written on the bomb body. Yes you’re right that you could set the AD in the SMS to what gets set by hand but that’s not what we do.
We set AD to 12 seconds: 8 seconds for guidance time + .8 seconds for CCG + 2.7 seconds for safe separation timing which gives you 11.5 seconds. We then round this up to 12 seconds.
When you speak of the pilot selecting a fuse you’re referring to him setting Nose, Tail, or NSTL. Depending on what fuses are used then yes you can DUD the bomb. However, the AD plays no part of this.
From this section of the 1-F-16CM-34-1-1:
With no JPF installed, any value between 0 and 99.99 seconds may be entered; the entered value will not be sent to the weapon, but will be used in computing the HUD LOW cue.
That is from the JDAM but the GP bombs work like that by default.
So in summary, what you set in the SMS does not get set to the bomb. It is only there to display an accurate LOW mnemonic to provide an indication to the pilot so he doesn’t DUD the bomb using the arming delay set by weapons on the ground. An inaccurate setting of NSTL will DUD the bomb, however.
Disclaimer: this is real world; BMS is different.
Same RL disclaimer(s)…
It can be both, actually…I’m getting my info from a Navy pub; and I’m also talking about another interface…which it sounds like has more options and flexibility. And after I looked again, it lays it out a bit more complex because I forgot that you can also get differing options depending on which initiator is used - in my world there can also be differing mode selections depending on that.
AD is simply the amount of time from release/initiation to allowing the fuse to function, and that’s really the bottom line - this is why the AD has to be less than TOF or you will get a dud…it has nothing to do with guidance; only safe sep/escape - as long as AD is less than TOF you’re good; longer for higher, shorter for lower. I mentioned “short” and “long” delay times because typically the pilot only has a choice of two options in the cockpit (other than zero…in some cases) even though there are more on the fuse, and I’m not into talking numbers.
Not setting AD may result in a dud because not setting it may mean that the pilot overlooked another step in his cockpit setup - like selecting fusing at all, or input of a partial program…in which case the rack (or initiator) may not function. This has less to do with what AD actually affects in the delivery and more to do with forgetfulness on the pilot’s part…seen it happen - overlook one step, you’ve probably overlooked more than one. Usually, one is all it takes though…
Pretty sure we’re agreeing that what’s set at the weapon doesn’t get sent to the bomb - what I’m saying is that if the pilot doesn’t set up his cockpit to match how his bomb is configured, the symbology will not provide him a steering solution that will result in proper function; and/or the jet may not provide signal to operate the rack properly to obtain proper function. And/or he may also overlook some other step that will cause a dud…as I’ve mentioned - there are LOTS of ways to screw this - or any weaponeering - up.
…we now return you to your regularly scheduled programming.