Maddog bms 4.35
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To quote the BMS1F-16CM-34-1-1 manual: Launching a aim120 in bore “allows you to fire a missile relying solely on the missile seeker to find a target. In BORE launch, the missile seeker goes active directly after launch and targets the first aircraft it ‘sees’. This mode should only be used for self-defence with extreme caution, as the missile seeker will not discriminate friend or foe (the brevity for such a launch is MADDOG for good reason.)”
However in the last major falcon pvp event I and the vast majority of players were employing maddog shots in bvr situations, at or near to rmax ranges. As evidenced by the pictures below there seems to be no longer a need for the jammer or even the radar whilst fighting bvr (as modeled in bms 4.35). You simply maddog in the bandits direction (via nails/spike or awacs bogey dope) and extend/press. If you(with jammer on) and the bandit remain high aspect, the bandit will receive a missile inbound before a radar lock is possible-placing him at a significant disadvantage. If the bandit in this scenario employs the jammer you can maddog at rmax and extend-if the bandit remains high aspect your maddog will go hoj-again placing the bandit at a tactical disadvantage.
In bms 4.32/33 I believe the maddog had a steeper ballistic trajectory(after the initial climb the missile would descend reasonably sharply) so that the pk of a maddog was very low. Since bms 4.34 the aim 120 maddog flies dead ahead until it finds something in its path. Therefore I submit that the current modelling of launching a maddog aim120 may need to be examined and would welcome the developers thoughts on this issue.The left picture shows a maddog launch from yellow at 30nm without radar lock(this missile goes on to track red)
The right picture shows that red receives a missile spike at 19 nautical miles from yellow, at this point red is unable to gain burn-through and must defend the missile. You can see red starting a roll to defend. -
Maybe that could be a good idea to start manœuvering in both altitude and direction in the 30NM range instead of flying straight
A mad dog fired at Max range is a lost missile anyway since it has no energy left if you manœuvre
This is we’re tactics comes into play , start pince at 30NM with your wingman for instance
A good chainsaw can be also very efficient
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Hey Mav, thanks for the reply. So are you saying that there’s no longer a need to gain a radar lock before firing an aim120 amraam in bms 4.35? Because as I have illustrated with my first post this will reduce your virtual life expectancy to about…0!
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Does anyone know if the antenna on the AMRAAM sweeps or does it have a fixed cone? I read somewhere about an active missile radar from another country having a 50 deg cone but I can’t find it and it was estimated. If so does the missile radar sweep when its launched mad dog and once it gets a lock does it train on that target then like STT?
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A segment about lock on before launch missiles:
A segment about lock on after launch missiles:
A note on home on jam alleged low precision navigation:
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I still had some questions on this topic and Sidewinder and I did a test. I will post the video link of the ACMI here. I have some questions for anyone that knows and maybe MavJp can comment as well.
The setup is as follows.
Shooter Sidewinder, Defender Sandman.
Launch parameters, Mad Dog, 30 NM Mach 1 Plus, Lofted missile.
Defender: once notified by shooter that a maddog has been launched will perform a notch 90 degrees with Jammer off.Flares: will indicate jammer has been turned off
1st Engagement:
Remained in the notch for extended period of time to observe what the missile does over an extended period of time and you can see that it is in Lead Pursuit
I would think that if it’s just tracking towards an energy source with no radar lock that it would not have the data needed to perform lead pursuit and instead would be pure pursuit. However it appears to have precise guidance in HOJ.
You then See me Flare which means I turn the jammer off and as I start my split S into the revers notch, the missile radar locks on but with no power and gliding has no endgame energy to reach me.
2nd Engagement
This time I will enter the Notch and Immediate turn the Jammer off and initiate a split S into the reverse notch.
Once inside of 24 ish Miles you will see the missile again pulling lead pursuit but I instantly flare (jammer off) and reverse notch.
What I see now is the missile continuing to track as If I was still moving in the same direction.
I would think that once that HOJ signal was lost, the missile has nothing to track so instead of continuing to pursue it would take up a constant heading and begin searching for targets.
Questions:
1.) Does the Aim120 perform lead pursuit in HOJ
2.) Shouldn’t the missile stop it’s pursuit and take up a more ballistic trajectory once the HOJ signal is lost with no target to track. -
We usually use this kind of tactic to intimidate those who like keep jammer always on and keep close formation in the BVR engagement.
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We usually use this kind of tactic to intimidate those who like keep jammer always on and keep close formation in the BVR engagement.
Yes there are all kinds of tactics to use, for instance a mad dog fired in the direction of a flight that are not separated very far or even locking onto a target and when the missile is pitbull when the aircraft are not separated far enough will generate a tracking warning for all aircraft within the cone of the 120 radar.
But this post is not about tactics it’s about if the behavior is correct or not so if anyone has any information this would be most helpful.
Btw i mentioned that tactic above because I’m not sure if this is correct missile behavior as well. I would think a missile that is tracking a target would not have it’s radar sweeping and generating a large azimuth it would be locked like STT thus nearby aircraft would not get a warning.
Nearby meaning outside of say 5 degrees or more of the tracked target. I’m thinking a missile pitbull at 8 NM then 10 deg or more in all directions would probably keep you in the clear from the missile warning. So 2 NM or more in a cone around the target should keep you from getting an erroneous tracking warning.
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I would think HOJ would allow LP because it could still do PN.
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Even old sidewinders fly LP don’t they… I assume they control to achieve a constant-bearing toward the target.
https://en.wikipedia.org/wiki/Constant_bearing,_decreasing_range
https://en.wikipedia.org/wiki/Proportional_navigationAs for continuing to extrapolate, optimistically, even after jammer off … well the Amraam costs a lot and is 1990s technology … I can imagine it holds some internal model of where it expects the target to be. (edit: just speculation, I don’t know about RL and also don’t know if this would be modelled in BMS)
Watching your video (second test) I agree it does seem weird that it continues turn, not fly straight … but otoh it’s decelerating, so I suppose it would need to continue to turn a bit, if it were holding a line of constant-bearing on a hoj target.
Maybe do a third test, where you just notch and continue (leave jammer on, don’t reverse)… to observe how much the missile has to continue turning as it decelerates, to hold you on a constant-bearing.
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I would imagine the missile would track pure on a HOJ signal. We have to remember the purpose of Jamming. It literally creates a vast output of radiated noise plus other clever tricks undisclosed to the public (creating false contacts etc…) Now the 16’s radar must be stronger than aim120’s? So if you can not get extrapolated data from a jamming contact (aspect, alt, speed, range) from that big dish on the nose of your 16… how is a AIM 120 going to manage calculating a lead intercept without burn-through and a smaller radar?
If a AIM120 radar seeker has more strength than the 16’s radar I would be surprised. So trying to think logically… A mad-dog would come of the rail…go active…then just fly pure to the radiated noise, I can’t see how it could calculate more info without burn-through… hence why mad-dogs have a much lower PK IRL
I may be wrong, I’m just thinking out loud here and will happily stand to be corrected.
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I would imagine the missile would track pure on a HOJ signal. We have to remember the purpose of Jamming. It literally creates a vast output of radiated noise plus other clever tricks undisclosed to the public (creating false contacts etc…) Now the 16’s radar must be stronger than aim120’s? So if you can not get extrapolated data from a jamming contact (aspect, alt, speed, range) from that big dish on the nose of your 16… how is a AIM 120 going to manage calculating a lead intercept without burn-through and a smaller radar?
If a AIM120 radar seeker has more strength than the 16’s radar I would be surprised. So trying to think logically… A mad-dog would come of the rail…go active…then just fly pure to the radiated noise, I can’t see how it could calculate more info without burn-through… hence why mad-dogs have a much lower PK IRL
I may be wrong, I’m just thinking out loud here and will happily stand to be corrected.
I have to agree with you on this and at the very least a very inaccurate course. Keeping in mind though as you turn to the side and notch with the jammer on the F16 you’re not focusing the jamming signal on the missile but the radiated energy is still there. So yes it would go towards the energy but not tracking it as if it had a lock on the aircraft.
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I don’t know if this could play a role as well but the missile will decrease the distance to the (jamming) contact massively and very quickly simply by flying in its general direction. I’d wager that an ECM pod is easier to burn through the closer you get to it as it “converges” into a single source of noise as the resolution of the missile improves due to the smaller distance by r² or thereabouts. Again, it’s all just guesswork and basically I have no idea what I’m talking about
All the best,
Uwe
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I don’t know if this could play a role as well but the missile will decrease the distance to the (jamming) contact massively and very quickly simply by flying in its general direction. I’d wager that an ECM pod is easier to burn through the closer you get to it as it “converges” into a single source of noise as the resolution of the missile improves due to the smaller distance by r² or thereabouts. Again, it’s all just guesswork and basically I have no idea what I’m talking about
All the best,
Uwe
Agree for sure… the closer the missile more probable for burn through… the factor would be how well the ECM “fooled the missile” into thinking where it should be… once the missile has burn through it would “go lead” I assume but the ECM may have dragged far enough to provide a safety net and high probability of a miss… all guess work and stabbing at common sense but interesting topic for sure.
I’m guessing here again, but I would think a missile inbound (even with HOJ capability) would have a lower PK than a tracked/supported shot on a jet with no ECM on… From the last TVT experience I would say this isn’t the case in BMS at the moment. MadDogs from 30 miles out had higher PK’s than shots fired with STT and supported. I’m pretty sure a maddog IRL would have an extremely low chance unless you were WVR close! For sure an interesting discussion.
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Depending on the jamming I guess but denying range information means the missile only has bearing info. Bearing LOS rate is exactly the same kind of info a Sidewinder has. Downsides to not having range is lacking or severely degraded notion of distance which hinders all the energy management stuff 120 does like lofting or not going full PN lead in case target doubles back.
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Presumably when the missile decides to home on a jamming signal, it keeps its nosecone radar switched off. (Wouldn’t want to warn the target pilot’s RWR.)
Can’t switch back on at last second “when close” because that’s the one dimension of information the missile doesn’t have: range to target. It’s just flying a line-of-constant-bearing to a bright point in the sky. No way to tell if that point emitter is close or far, fast or slow, high-aspect or cold-aspect.
This type of tracking is probably not accurate enough to impact, but the radar is on a gimbal, and the warhead can be triggered to detonate at the moment it flies past the signal source (when the gimbal suddenly hits the limit … again presumably just like a sidewinder).
There are more RL-vs-BMS questions here … eg. do jammers just blare music all the time, constantly, or do they emit delayed false-echo and fake-doppler shifted responses to fcr signals? (ie. Do you, or a wingman etc, need to keep sweeping the target frequently with your F-16 radar, in order for your amraam to continue guiding on the jammer signal?)
Also related, is a question of whether the missile continues to receive DL information from the F-16 when in HOJ mode… I suspect this level of detail is probably classified, and a continued area of innovation in the -D models and software updates to the older models… sounds like the modern gen have GPS receivers and can get guidance info from AWACS and land/sea radars and other sources.
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After a few hundred BVR engagements during the last 4 TvTs along with PvP BVR engagements in dogfight mode, some issues have become very apparent since the release of 4.34. (Growing pains with the increased fidelity since 4.33).
Spike and Scan Pattern
AIM-120’s are able to spike every member of the flight within a 120 degrees × 120 degrees cone. Ignoring the missiles search cone, scan pattern, etc. since it is all classified; we do know that it is physically very unlikely that the AIM-120’s onboard radar is more powerful than the AN/APG-68 on the F-16 itself due to size, cost, etc. The missile’s scan pattern should tighten down to STT once a target is acquired. As it works currently, an entire flight can be put defensive with a single missile due to its ability to spike every member at once. The fact that it does not decrease its search cone once it acquires a target makes even the widest formations intended for maximizing BVR employment ineffective. Tactics are not the issue and are not the topic of discussion hereHOJ Accuracy and Kinematics
In the majority of BVR engagements, players appear to be using the AIM-120 in BORE mode firing MADDOGS. The high accuracy of HOJ is allowing MADDOG to be the primary method of employment in BVR rather than for self-defense WVR. It is not authentic and does not match any descriptions provided by real manuals or BMS documentation. Although good tactics and teamwork can help to mitigate the issue (I have never personally been killed by it, but had some close calls), it is still very “gamey” compared to before and heavily decreases immersion since it becomes the focus of each engagement. Some communities have even gone as far as creating entire theaters to remove the HOJ feature because it was deemed unrealistic.F-16 Basic Employment Manual, Volume 5
“MADDOG—[A/A] Visual AIM-120 launch.”TO BMS 1F-16CM-34-1-1
“This mode should only be used for self-defence with extreme caution…”
“…the precision of this kind of navigation (home on jam) normally is very, very low…”Even mav-jp’s own words “A mad dog fired at Max range is a lost missile anyway since it has no energy left if you manœuvre…”
(even though this is not the case anymore; AIM-120’s fired in HOJ exclusively at r_max and r_aero appeared to kill more friendly and enemy players than any other mode in TvT from observation)I believe that most of the issues with BVR combat stem from these 2 problems and can be fixed without classified/unavailable data.
- Search cone reduction once missile has gone active and target is acquired.
- The onboard radar is not as powerful as the F-16’s AN/APG-68. It should either go STT or tighten its search cone significantly once a target is acquired.
- As it is now, it even outperforms the AN/APG-68. And can spike multiple targets both separated by up to 120 degrees of azimuth.
- No Loft for HOJ
- AIM-120’s fired in BORE mode (MADDOG) were not an issue in 4.33. One of the primary reasons for this is because they did not loft like they do currently.
- Although I am uncertain if they technically ‘loft’ like a traditional radar lock, their behavior is practically identical as it stands. The missile should continue straight rather than arcing back down magically to the area where the target is when fired up into the air. Currently, you are able to point the nose up and the missile will arc back down near the target very efficiently and will find them the majority of the time. It is unlikely that you will go unseen by the seeker unless you are in a lab scenario where conditions are controlled. This may be fixed by #3 below.
- Although ECM is able to mask the target’s altitude, it does not conceal the bearing. This is why the brevity call for a strobe is made in terms of bearing.
F-16 Basic Employment Manual, Volume 5
“RAMBO 1, STROBE 360.”- The missile should not loft the target since the altitude using HOJ exclusively is unknown. In the F-16, you have the contact azimuth, but need to burn through to find altitude. This is also why the F-15 displays strobes as vertical lines; altitude is not known.
- Although it is a different jet, the F-14 uses a similar idea with AIM-54’s. By flipping up the ACM switch, the missile is active off the rails and goes in a straight line until it acquires a target (no loft).
- Making a MADDOG unable to loft like 4.33 would relegate it to defensive usage WVR due to kinematics, and would make it match mav-jp’s description, the BMS documentation, and the F-16 Basic Employment Manual.
- HOJ accuracy decrease as range increases
- From the link posted by AWmk1,
“…the precision of this kind of navigation (home on jam) normally is very, very low…” - As it stands now, MADDOG can be used as a primary employment method and does not match this description, nor the statements from the F-16 Basic Employment Manual+BMS Documentation.
- Since no real data is had, Unleashed Code proposed the idea of a probability matrix ‘cloud’ surrounding the aircraft rather than an absolute. Since the altitude is unknown, a cylindrical cloud surrounding the aircraft could be used to represent the ECM noise.
- If the missile is fired at longer ranges, the probabilities of maintaining track could be very low. As the missile gets closer, these probabilities would increase.
- This would allow defensive employments of MADDOGs in WVR to be effective and make long range employment of MADDOG using HOJ inaccurate and kinematically inefficient. This matches descriptions from the F-16 Basic Employment Manual, BMS Documentation, developer statements.
Without real data, we should strive for an authentic simulation of BVR combat rather than looking for realism with non-existent data until said data is made available. There’s plenty of anecdotal evidence out there of viper drivers being able to use real BVR flows in BMS, and I would like for it to stay that way and continue to be the most authentic BVR simulation out there.
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Agree a lofted-trajectory would be weird / unlikely, for a maddog shot.
In the test videos, I assumed the shooter’s aircraft was pitched up ~20 degrees before firing?
The boresight for the mrm is about 6° below the gun cross. I just jumped in a plane and fired a maddog… hit shift+7 to watch it… it seems to fly straight, slightly downward (my aoa was about 5-6°).
I always assumed the large circle on the HUD is meant to represent, roughly, the conical radius of the missile’s seeker… is it just arbitrary HUD symbology?
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…There’s plenty of anecdotal evidence out there of viper drivers being able to use real BVR flows in BMS, and I would like for it to stay that way and continue to be the most authentic BVR simulation out there.
Really nicely summed up Punch!
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all of this is very interesting
translating some ideas into code can appear to be difficult though as this is very touchy , especially in MP