Question on Harm HAS ALIC and RWR display
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If the s-a sites are on the briefing map, you can set target steerpoints at them and them use the POS methods of AGM delivery which will give you HUD cues for distance.
If the sam sites are NOT on UI map and are only mentioned in briefing information under threats (ie. “SA-5 located 3 miles NE of Wonsan”) and thus you have to use the HAS mode to fire HARMs, which offers no distance to target information, the only ways that I have been able to estimate distance to targets to see if you are inside the weap delivery zone is (1) to place target steerpoints at the estimated position of s-a threats using the threat information listed in briefings (this will require you use map features to show political sites -towns/cities - and their names and zoom in to find) or much easier, (2) if the HAS shows a threat target out in front, lock it up and command your wing to “attack my target”. The wing will respond with a “roger, attack target at XXX degrees YY miles”. He gives you the miles and based upon your altitude and loft you can judge whether you are within the weapons envelope to fire. And unless you want you wing to actually attack the target, make sure you immediately command him to rejoin or else he will gladly fly off to try and kill it.
Hope this helps.
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i was thinking and one can correct me if im wrong that the horizontal grade line gives you indication of the radar location to the left or right ( angle ) while the vertical grade gives you a distance to the radar as in a top down view , is that correct ?
I foresee some experimentation in the training mission with PPT 59 and PPT 56 in particular.
If anyone can discover some form of manual for HAS mode I for one would be extremely grateful. I’d like to do a tutorial on it but it feels like I’m missing something important with it.
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another way is to experiment as to where you pick up the target in HAS mode. say its 80nm, the HARM envelope. as soon as a SAM appears on HAS mode you make an OA point with range 80nm and bearing,say, 360. and you have your location
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i was thinking and one can correct me if im wrong that the horizontal grade line gives you indication of the radar location to the left or right ( angle ) while the vertical grade gives you a distance to the radar as in a top down view , is that correct ?
From the training manual:
“The WPN page displays the ALIC which is the HARM WIDE field of view ahead and down by default.”
I took that to mean that the vertical line represents elevation (similar to the boresight view once locked). Not sure if that’s right or not though.
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ALIC is Aircraft Launcher Interface Computer. It’s the support electronics (built into the launcher rail) that interfaces with the MIL-STD-1533 bus allowing the airplane to specify target parameters.
I don’t think it’s 10 degree increments because the weapon can detect emitters seriously far off in azimuth. It would be easy to test though. Find an emitter in pre-designate HAS and turn the airplane to place the symbol on a hash mark and note the heading. Lock up the emitter and then turn the airplane to center the symbol in the ALIC synthetic video view and note the heading. That would be your angle.
The vertical position is elevation and the horizontal position is in azimuth. The long crossing lines represent 0 elevation and 0 azimuth. Note the difference in the wide/narrow/left/right search patterns.
HAS you want to think of as an anti-radiation Maverick. I guess the details to know would involve the threat tables and selecting which from that table to show/hide. It’s the simplest mode really. See, lock, shoot. It flies straight to the target so avoid skimming the ground at a shallow angle.
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Sounds like you can git target slant angle from the harm seeker. And you know ac altitude. Should be able to trig the target range. Shrug…
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Besides, the RWR usually tells you if the SAM itself is in firing range or not (to shoot at you). If you know what its firing range is, you get a non-too-accurate but usually good enough idea of the SAM distance to your aircraft, so you know if you can shoot a HARM or not. It doesn’t work really well only with long-range SAMs, like SA-5s or SA-10s, which can outrange a HARM.
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frederf, yes you get spots in HAS mode in whatever azimuth, even in your six oclock, since the sensors can pick them up. But you can only shoot the HARM when its within 30 degrees azimuth which is the max offset that the HARM can be employed.
Final note, the HARM when shot, pops up so shooting while skimming isnt a problem -
Not in HAS it don’t. I think you are talking about HAD not HAS.
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check it if you want
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I’ve never checked if the HARM sensor in HAS is capable of detecting something right on 6 (180°), but there’s no doubt the sensor we have now in HAS can detect radars in the rear hemisphere. Bong’s right.
I tested it when I wanted to understand how to use the scales. -
I plan to do some testing later this week when I have time, but one question comes to mind. Do we know how well HAS is simulated in BMS? How close is it to the reality?
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In 4.32 it would bee-line it for the target AGM-45 Shrike style. In 4.33 it’s different. I didn’t test if it was exactly the profile of a HAD or POS shot but qualitatively similar.
The display markings are in 20° increments horizontal, 22.5° vertical. The caveat is that while the straight lines suggest it’s supposed to be a B-scope format but the symbols are being positioned in a different way. The scale is only directly readable when a contact is on the central vertical line. As the contact changes in azimuth it follows a semi-circular path where the 1 o’clock position is 30° right, 2 o’clock is 60°, 3 o’clock is 90°. The horizontal scale works but you have to use your imagination to compare the curved path length vs the straight line scale. The extreme ends being 60° would curve around to the 2/10-o’clock positions. This is only really usable in the central ±20 degrees or so near where the straight horizontal line and the arc the contacts occupy come tangent.
The vertical scale will show the contact at the top when it is on the horizon (low altitude ownship + long range. Approaching directly the contact marches down the vertical scale to 45° down at the second tick and overflight at the 90° point is the “fourth tick mark” which is the end of the line. The 1st and 3rd ticks are 22.5° and 67.5° respectively. Contacts at a mixture of azimuth and elevation are nearly impossible to quantitatively judge. A contact 60° left in azimuth and 45° down in elevation will be drawn at the 2 o’clock position but at half the radius from the bottom-center of the display as one on the horizon.
The HARM can only maintain lock within ±90° azimuth and +?°/-90° in elevation. The contacts will remain visible on the pre-designate HAS display but will not be lockable and will drop lock outside these limits. Contacts beyond 90 degrees in az/el are clamped to the bottom of the display at their clock position in the rear hemisphere. For example a contact moving through 91 to 179 degrees azimuth will appear to slide along the bottom of the display from the bottom corner to the bottom center.
HAS has 4 search displays, wide, center, left, right. Wide and center appear to have identical display characteristics. The only noticed difference was that center detected contacts at a shorter range (40nm for SA-2/3/4). Wide detected these SAMs at much longer ranges.
Despite the shift in the vertical tick-marked line in left/right displays, contacts in the center of the display are still straight ahead. Contacts which are even slightly left azimuth in “RT” or right azimuth in “LT” are not shown.
HAS is stabilized in both pitch and roll. ALIC video (post-designate) is stabilized in pitch but not roll (which seems wrong). Post-handoff video puts the contact in the middle of the crosshairs when the elevation is 45 degrees downward and lower as overflight continues.
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Compared to reality: The pre-handoff video contact positions are most certainly supposed to be arranged in an X, Y grid where X is azimuth and Y is elevation so any point on the display is meaningful not this arc. The tick marks would span the entire FOR of the HARM which is unknown to me and much smaller in elevation (possibly 10). Looking straight down is silly and you’d be much more interested in minor depressions below the horizon. A cutaway view of the missile radar dish makes a wide range believable but so would a narrow capability especially for early models. HTS is often praised for its 180 degree coverage which wouldn’t get so much press if it wasn’t a significant improvement over the missile itself. Anyway if the HARM genuinely has ±90 then the tick marks would be at 30/60/90 for wide.
There’s no pre-handoff cursor. You press the OSB next to the threat type you want to handoff. If there are multiple (up to 4) after handoff you press uncage to step through them. No SOI, no slewing, no TMS-up’ing unless there was a software change.There is a HAS cursor. Pressing the threat is an alternate way.The threat tables are customizable (DTC), one might have Search, SA-3, and SA-10 on a table if you want. They interact naturally with the HARM DED page when the UFC link OSB (5) is pressed.
Post-handoff the video is from the missile’s point of view in roll and pitch (instead of azimuth and elevation as in pre-). Center of display, boresight of missile. If the contact is to the right, roll right until the contact is 12 o’clock and pull up to center the contact.
Scans can take a long time the bigger the FOR and number of contacts searched for (up to 5), like a minute and a half. 5-contact wide rarely takes more than 15s currently. “RS” restarts the scan, clearing the last contacts.
Center is a narrower scan centralized so the azimuth tick marks represent smaller angles and it finishes scans faster. Right and left scans would display a straight ahead contact on their respective 0 azimuth lines, not the center of the display.
Since there is no range information in HAS, the missile would either fly direct or g-bias minimally similar to Maverick.
Presence and operation of the HTS may or may not have an effect in HAS.
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The scales don’t seem to be of practical use. At 20,000 feet there’s not much movement at all. You only really see a lot of movement when SAM’s are in the air.
If centre range is 40 miles I would imagine the way to use it would be to use wide for situational awareness and drop down to centre to verify within a good range?
And what does DTSB stand for? Answer: detected threat status box
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In testing using the HARM training mission the SA-2 was present at WIDE above 60 miles, the SA-3 at 52 miles. In other words as soon as the mission started.
Both threats appeared at CENTRE at 36/37 miles.
That range is perfectly fine for the SA-2, but for reasons I’m unaware of a HARM fired at the SA-3 misses at those ranges. And I’ve fired a few missiles post designate, RDY, etc. I would have to do more testing but 30 miles or below would be my guess at that point, having missed at 36 miles and hit at 24 in my last test, with range taken from PPT 56. I’m guessing range is accurate as both SA-2 and SA-3 popped up at the same time at CENTRE and at the same PPT range.
Are there different effective ranges for different threat types?
I’m going to partially answer my own question: the SA-2 Fan Song has a 40 mile range, the SA-3 Low Blow 25 miles.
But still, what is the HARM sensor detecting at 36 miles with the SA-3?