Yes, the Phoenix is over performing at sea level.
Yes, it is likely the thrust value is for 45,000ft.
But what about 60,000ft?
If thrust matches 45,000 feet and it is adjusted for that scenario, performance above that altitude will be slightly underperforming and at lower altitudes significantly overperforming. That is why gaijin adjusts most ordnance to 0-5,000m range and performance charts. Meet in the middle.
The Phoenix is adjusted for very high alts, so overperforms in majority of use cases in-game.
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With current loft profile, yes. Missile doesn’t really goes above 10,000m and tends to dive very quickly even when fired at higher altitude.
But if loft is fixed and missile goes higher, then the missile will spend more time above 45,000ft, right?
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It’s a mute point that it climbs during loft because what will end up happening is it will again overperform at low altitude if you fix the extreme high altitude performance. Nothing changes here.
Either it matches the performance at 100,000+ feet and then has double or triple range at low alt, or it is modeled for low to medium alt and underperforms in extreme long range scenarios. The latter is how missiles are modeled currently. The only exception seems to be the AIM-7F which has too much thrust and is capable of exceeding its’ own launch diagrams at both low and medium altitudes. It needs a revision.
The R-27ER for example was adjusted to 0-5km altitude and thus underperforms in high altitude performance. The AIM-54 is no exception to this and complaints about it are honestly tailored or biased in some respect. R-27ER is missing 100 m/s from the top speed, and up to 20% of its’ range in high speed + high altitude scenarios. The AIM-54 is also missing some top speed but meets the correct range figure in the correct time, at least… which suggests overperformance because it carries velocity for too long at a certain distance… thus overperforms in maneuverability for a larger portion of the flight envelope downrange.
I understand the concern.
We all know game does not simulate varying thrust over altitude. Changing loft alone will certainly make Aim54 overperform even more.
However, thrust can be reduced along with the change in loft.
I remember this:
Changing loft gives opportunity to make Phoenix more or less correct both in high alt and at sea level.
Remember the tests done earlier this year? Increasing in loft will increase max speed attained by missile, but it has very little effect on the flight time (TTI differs only by few seconds, which translates to 5% ish difference), since missile flies longer distance despite it flies faster.
If there is a change to Phoenix, I expect it to reduce thrust, but greatly improves lofting so that it actually climbs over 10,000m after launch, so that it can fly faster, thus retain more or less correct number at long range when fired at high speed and high altitude.
There is another thing that concerns me. Current state of Aim-54, even without the change mentioned above, just doesn’t look right. Since, in China, Aim-54 is considered more or less an equal to PL-15E, and less range than PL-15, and PL-15E already superior to any Aim-120 variants in service.
PL-17 > PL-15 > PL-15E ~= Aim54 > PL-12 ~= Aim-120
Aim-54 having less firing range than Aim-120 is just very wrong. Since that means Aim-120 > PL-15E, which we know isn’t true. Otherwise US wouldn’t have started Aim-260 project.
It would be far more effective to adjust the drag based on altitude so that a correct loft profile yields better higher altitude performance while simultaneously correcting the overperforming sea level performance. The thrust can stay roughly the same, or they can adjust the burn time a little bit.
Obviously the most correct method of fixing this issue is to have dynamic thrust and drag conditions.
True, however, I don’t think the game has this system. The only way to affect drag is by sending missile higher, which is what loft does.
We know missile reach correct altitude in game, but there is no data on when it reaches correct altitude. So technically we can make missile climb faster in game, and reach the “correct altitude” sooner. So that it enjoys longer time with reduced drag; thus achieving a similar effect.
But this is something dev has to decide. So, fingers crossed.
That will be even better.
What is the current in game drag and what should the drag be changed to?
It is easy to model.
Drag is not a purely static number, necessarily. It changes with air pressure which changes with altitude. The missiles have a variety of factors accounted for in the drag model to include length, width, possibly a few other unknowns. The variable that primarily adjusts the drag is something we can mess around with and edit on our own in custom missions.
The missile should reach altitudes of 100,000 feet in a ballistic trajectory. 30,000m
It’s over performing by a little below 10,000m, but above that altitude it is massively underperforming if it spends the majority of time there.
Drag system for missiles will need to be reworked at some point to be more accurate.
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This 800% and just in general.
The 54s seem to suffer the most due to their girth and its the most noticeable, but drag in WT across the board is just really jank, from missiles to aircraft.
I would love to see gaijin overhaul drag and channel loss calcs so they are more accurate, or at least look back at the values once more since there are very obvious faults present, EG, the TF34, a open face, high bypass turbo fan, which flat out has no mount that impedes airflow because it’s turbine frame is part of the install, somehow has channel loss.
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I totally agree, whenever I get down tier to fight F-14, I can consistently fire new ARH at 50km range, at Mach 1.4 + 8000m + 45 degree manual loft, and lands a consistent hit even if F-14 pulls as hard as it can (~10G) when missile is ~6km away. Where as Aim-54 struggles to hit, when firing at similar condition, even if target is flying at a small aspect angle (say 10 degrees) and not maneuvering. Since Phoenix will immediately try to nose down and refuse to climb higher, then loses a lot of energy from drag. Resulting Aim-54 has way less effective range than Aim-120.
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You can’t manually loft aim 54s. They correct themselves 17.5° either way.
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Based on what?
Aim-120 has even lower loftElevation at 7.5, but Aim-54 don’t have timeToHitToGain3, so Aim-120 nose down slower.
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Drag is oversimplified in warthunder because it is simulating everything as if it was in the troposphere.
In the stratosphere, anything not traveling at hypersonic speeds experiences practically no drag, but the aim54 which would be in a ballistic trajectory in these altitudes - where it cannot even effectively manuver due to a lack of air, should not be affected by drag at all, its would be so close to 0 that it may as well be 0.
In warthunder, drag above 12,000m is linear, when IRL it should be expoentially reduced. The game was not designed with anything going higher than this. The Aim54 still experiences a signficant amount of drag when it shouldn’t.
After reaching it’s apoapis, the aim54 should start to accelerate under gravity until it returns to the tropopause, in warthunder, its speed still reduces due to drag.
So at the time of Impact for the longest range shots, the missile might be traveling 300-400m/s slower than what it should be.
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Okay, thanks for clarifying. I’ll now inform you that when conducting the maximum range test the loft elevation is nearly correct and the missile still (even with the additional drag you mentioned) meets the target at the correct range and time. Correcting the atmospheric conditions would only cause overperformance, and it currently is not underperforming in max launch range conditions.
The time to target is correct, but the speed on impact and the speed throughout the flight duration is not correct.
Even after 3 minuites of flight time the misisle should be going between mach 1.5-2.0 and the missile should glide at mach 2.0 to 2.5 for more than 50% of the flight duration.
At shots more than 80km the misisle should be falling at almost a 70 degree angle to impact the target.
The trajectory shape will often barely affect the time to target, but massively affect the speed on impact. All High lofted missiles in the game don’t perform anywhere near as they should and run out of energy far too soon.
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Based on what
Idk bout that, based on the current poor loft trajectory? I’ve already been saying the top speed is less than expected (so are most missiles, and especially the R-27ER)…