The 12km limit is seeker related, or the intercept point of target from launch. It’s not a valid figure to go throwing around in comparison to the maximum target distance at launch for RIM-7M…
Well, where are the proofs of these statements?
There actually is super cruise capable aircraft in game atm electric lightning being one
We know the impulse of the motor, and we have a general idea of the drag of the missile. Any way we look at it, even with a drag value significantly higher than what is possible… it has range >12km.
So it has to be a seeker limitation, slow target, or point of intercept (not distance of target from launch).
The grid fins have the same or similar drag to conventional missile fins until high subsonic regions (0.8, optimized fins such as R-77-1 are better up until 0.9+ mach)… and the transient from 0.8 to 1.3 mach is but a very brief portion of the missiles’ acceleration.
The grid fins allow the missile to maintain the higher “peak” speed for a longer duration, severely offsetting the issues in the transonic region.
The primary reason other countries have not utilized grid fins since is to minimize missile RCS. This, and to reduce drag in transonic region when missiles are on the pylons.
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I will also add that the grid is very difficult to choose and design correctly.This is thousands of studies and purges.There’s like a wing profile
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Also helps explain why the R-77 went with a short-burn high-impulse boost motor to get to speed as quickly as possible
IIRC one of the main reasons I’ve seen proposed for the use of them was that the actuating servos could be smaller, lighter, and less power demanding as grid fins both have a smaller arc of needed movement as relative to conventional fins they function at relatively low AOA and as they require less force per degree of movement in that arc relative to a conventional fin. In the waning days of the USSR these might have been more compelling than today, as the increased efficiency of modern actuating devices might make the need to reduce the needed work from them a lot less compelling relative to how much space it saves inside the missile
Oh yeah, I’m not saying lattice fins are bad. They clearly have their advantages and are used in applications such as large bombs, ballistic missiles, and reusable rockets, but they are DESTINCLY not used for air to air missiles, and considering their extreme drag penalties in the transonic regime while having no major drag advantage in most/all other flight regimes barring high supersonic speeds, its highly dubious they are worth it.
As you said, their primary advantages are their low hinge moments requireing smaller servos, and they also have packing advantages (ie: they can be folded nicely for use in internal weapons bays).
Despite these advantages though, no other nation has bothered with them for air to air missiles. None of the western aligned nations despite having tested them extensively and using them for stuff like MOAB
Nor has China, which operated R-77’s:
Nor does Russia with their most modern R-77 variants:
Or even their hypersonic R-37M Axehead:
Even throttleable ducted ramjet missiles like the MBDA meteor, missiles that would prefer operating in the high supersonic regime due to that being the optimal region for ramjets, don’t use lattice fins:
Lattice fins have their advantages and are used in applications where space or weight is at a premium, NOT in air to air roles, and most certainly not in surface to air roles either. There’s been tons of silly arguments made as to why the new R-77’s gave up on them as well, or why every other nation, despite having extensively researched lattice fins haven’t used them on air to air missiles, but the real fact of the matter is that the fins likely just don’t offer any notable advantage to offset their massive drag penalties in the transonic region. If they did, you’d see some other air to air missiles use them, but they don’t. Sacrificing missile performance for any subsonic or transonic launch in exchange for a moderate improvement in performance during supersonic launches was likely deemed undesirable.
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hold on chief , it is not like he is wrong here , also he is not :
1- impolite
2- irrational
3- irrelevant
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It’s a discussion, and he is repeatedly posting things that are known to be false while also ignoring those that have information counter to his (false) opinion.
Such as;
Grid fins are worse until high supersonic…
When in reality they are equal to conventional fins at low subsonic, worse during transonic regions, and equal again at supersonic 1.3+ (for unoptimized fins)… and then superior at speeds 2.5 mach +
The fact of the matter is, the R-77 accelerates to at least mach 4 over launch speed in approximately 6-8s. If launch speed is 0.8 mach, it will be exceeding mach 1.3 in less than 1 second and burns little additional range at high altitude due to this.
Let’s assume 0.8 mach launch, the missile comes off the rail and accelerates. 4 mach / 8 s burn time = 0.5 mach per second average acceleration. 0.5+1.8 = 1.3 mach. In 1/2 second it has exceeded the transonic drag region. Add an additional half second to account for drag at sea level and… boom it’s not a huge concern.
Even considering a slower launch, the missile is still gaining speed normally until it eclipses the 0.8-1.3 mach region. It is additional drag, yes, but it has reduced drag at high supersonic… which is where it sits for a good proportion of the flight. This offsets whatever incurred drag happened in the transonic region or even recovers from it completely.
Your average player in war thunder will be cruising at 1.1-1.3 mach even at sea level. If anyone were to turn around and try to outrun the missile, they’d be doing so before it gets transonic again.
So when it comes to the R-77, the transonic drag isn’t even a serious concern from launch or in tail chase… but it’s repeatedly brought up as a point of contention.
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Spoiler
Paper discussing missile fins
Spoiler
paper about lattice fins in detail
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seems that only in the transonic regime the Lattice fins actually underperforms compared to tradicional ones, and they actually outperforms them at high supersonic, both in drag and control.
Yes, these sources and others have been shared repeatedly and yet @MythicPi continues to state falsehoods at intervals that skew others’ opinions on the lattice fins despite being shown this in both English and Russian.
R-77 will fall out of the sky at low subsonic speeds (think MOAB) and will rarely reach the higher Mach numbers (Mach 3.5-5). The R-77 fired under game conditions will likely be at low altitude and in the transonic speed range, it will suffer immense drag penalties.
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Additionally in the case of R-77-1 you have a real life launch with parameters shown, even in a nearly optimal 12km+ .95M+ launch scenario the absolute maximum range of the improved R-77-1 was 90km.
Needless to say while the R-77-1 might be capable of 90km under optimal circumstances the base R-77 with all the disadvantages of lattice fins, at low altitude under WT conditions, will be a very high maneuverability ARH with limited range.
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The video has insufficient information to make assumptions of range and there are three fantastic sources above discussing the advantages of the lattice fins… (stating the only serious downside is the radar cross section of the fins)…
Anyhow, if you want to read further and stop spreading misinformation, the info is available. This thread will be 500+ comments in no time if you continue to perpetuate the misinfo (whether you’re aware it’s misinfo or not, I’m not sure) but it seems it is usually spread immediately after sources are shown indicating otherwise.
On the left side, you can see the line with numbers 20, 40, 60, and 80. That’s the distance in kilometers. The small arrow on the right side of the line shows the distance of the target. The rectangle on the rights side of the line shows the min and max range of the missile (notice how the max range shrinks).
In the upper left corner, you will see two numbers. The bottom one shows a speed of Su-35S (km/h), and the one above shows the speed of the target.
In the upper right corner, you can also see two numbers. The bottom one shows an altitude of Su-35S, and the one above shows the altitude of the target.
In the bottom right, you can see a missile type - “77-1”.
What’s going on:
First, he fires two missiles at the target that is on approx. 10k meters of altitude. Then, notice the sudden switch of targets altitude and speed just before he fires his third missile. This most likely means he engaged the second target.
“Not enough info”
This information is available and unavoidable.
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Some of the information you have stated is not what you think it is, and this was discussed I believe in the R-77 thread already. What you think is multiple targets is actually one target and he is at low altitude iirc. This was a lengthy discussion with people (no offense) more knowledgeable than yourself and discussion / comparison to other documents showed it to be such.
Of course supersonic launches are tested. It’s how they determine operational limitations.
Yeah, going super-duper fast always maximizes range. No one contends with that. But it comes with its risk never mentioned because all we know is DCS and WT. Video game knowledge.
Notice how almost every launch done at supersonic is at high alt? Because it’s very detrimental to a missile to launch any lower in the dense atmosphere. That is more evident that missile launches are usually done subsonic. Especially in combat.
Secondly, the aim-120 is hyper dependent on the launching aircrafts radar and datalink. The farther you sling an aim-120 the less effective it becomes. More susceptible to jamming and natural disruption. Some aircraft capable of using the Aim-120 barely have detection ranges further than you can probably sling an aim120 going Mach at high alt… It’s pointless unless for aircraft like the F22 which is specially designed to drop them at a high rate of speed. Sitting on rails severely limits high speed launch performance.
You ask any pilot if they ever go supersonic to launch the aim120. Their reply would be like why? Why strain the missile and the signal and data from the radar to it? The Aim-120 is already capable 40 NM range subsonic. It’s a medium ranged missile.
Why take the risk just to squeeze some miles out of it and make it a coin toss? The risk of totally wasting an expensive missile is not worth the reward.
Simply wait for them to get into range. Do you believe GJ will implement a 40 nautical mile range launch at subsonic for a medium ranged active homing missile of Western decent? Absolutely not. So what is the point of determining max range when slinging it 42,000 ft flying supersonic?
I don’t think you should be answering for everyone. I certainly think they will give 40NM range for subsonic launched missiles at altitudes of 13,000+m as is possible with the AMRAAM. Fairly certain the AIM-7F can do it already if it just had the seeker range. Of course, no missile will have 40NM range on the deck except for a select few such as AIM-54 due to lofting and other factors for some time.