Has the lack of lofting on the GBU-24 been reported?
I mean obviously the trajectory is to blame for it. The issue is that while GBU-24 gets up to Mach 1.0 when impacting the target, the AASM only reaches Mach 1.05.
Is this the kind of speed you would expect from a boosted bomb free falling on a target at an angle higher than 60° ? I don’t think so.
So my guess is either drag is too high or thrust is underperforming on AASM.
Terminal velocity for a 2000lb weapon is roughly around mach 1.0-1.05 ~ I’d expect a small weapon based on a MK.82 to be around mach 0.9 ~, most of its boost duration is used to loft it over the target area. So yeah 1.05 mach would be about right. Considering you launched at mach 0.85 as well, so the AASM needed to also accelerate up to 1.05 mach while performing a loft.
But on the other hand the AASM is lacking quite a significant amount of range, which is probably attributed to overall drag, as the boost time is correct (and the thrust should be somewhat close to reality as well). The terminal velocity should be impacted quite a lot by the aerodynamic of the bombs, with the AASM kit having a significantly different aerodynamical profile compared to dumb bombs
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i’ll play the devil advocate here, but where have you guys seen that the AASM is lacking range ?
There are sime things wrong with this missile, like the weird trajectory for high and far shots, and the lack of loft on a low altitude shot, but range wise it seems quite correct.
And it’s not like range matters that much, since the missile takes a whole business week to arrive when fired from that far
The AASM max range is 80km from high altitude launches, and it falls at around 50km iirc (15km launch supersonic), meaning it’s missing about 35% of its range, which would be achieved with lower drag overall
In the AASM IR paper, it is supposed to recognize scenes that has a surface area of between 2 and 4 square kilometers. Using these scenes it was used to develop the ATR algorithms.
you mean this part?
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We know 3 things so far from primary sources.
We know that the maximum launch speed is Mach 1.4:
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We also know that the maximum launch altitude is 40,000 feet:
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So given those 2 sources, we can conclude that the maximum range should be obtained at the maximum altitude of 40,000 feet with the maximum launch speed of Mach 1.4.
So what is the maximum range? The 1,000kg variant is supposed to achieve 70km while the 125kg variant is supposed to achieve 90km. We have the 250kg variants:
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Testing it by doing Mach 1.4 and 40,000 feet. The maximum range was 66km. We know that the burntime is correct so they either have to reduce drag (improbable) or they have to increase thrust:
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AASM Hammer does not have enough range // Gaijin.net // Issues
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Yes, the IR algorithms was developed with different scenes in mind and be able to recognize similar markers of where they may be able to find a target is how I understood it from this paper and other brochures.
I gave that a read.
If I’m honest with you, the 2x2 or 4x4 is not a metric like that. As the document itself says, these were sizes used in development. The system might be locked to them, might be able to work on bigger, might be locked to smaller (imo 2x2 and 4x4 seem fine, so I will stick with that)
The thing is, recognize =/= see. It means that if it sees something within the pre prepared square it should recognize it. So it does not provide a seeker FoV, just the area where algorithm knows where it is.
Ofc it might be scanning the whole 4x4 area, but the document does not show this, unless I missed something.
What would be the purpose of providing scenes bigger than what it would realistically see for development with them knowing that the seeker of the missile is set to turn on at the altitude of 1.5km away from the target?
It’s supposed to be able to see the pre-prepared square itself in order to find features of the landscape and discriminate against those landscape to find the target.
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Is this written somewhere? Honest question, I might have missed that.
My point is, maybe it could find its position in a 1x1 square for example. Maybe even 0,5x0,5.
As long as it is not a perfectly flat surface there are some unique things that could be used to identify where it is.
Not sure what are FoV of other missiles like Storm/SCALP or Taurus.
I’m not sure I get what is going on in that report. The screenshot shows the bomb having travelled 67.2 km (the maximum range you claim it to have in game), but it is still well above the ground in that screenshot, so could presumably keep on flying a while further?
That is as far as I can tell the only source you have presented in support of a 90 km range for AASM (the other source from Rafale International says 80 km). There is a big problem with that source though: it says the 125 kg SAAW has a range of over 90 km. The SAAW is a completely different weapon to the AASM.
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Yes, I’ll have to refind it and upload it here. It’s supposed to filter out the recognized landscapes such as roads, buildings, which was uploaded previously to the AASM-IR before launch so it can then filter out the landscape and find the target which it is supposed to recognize.
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The AASM-Hammer then exploded after traveling that far. It has a battery time of something like 250 seconds. Now theoretically Gaijin could just increase the battery time and say “that’s it” but it would be up to them if they can find it believable that the battery would last much longer versus the idea that it is supposed to strike a target within 250 seconds. There’s 4 different class of AASM bombs. These are 125kg, 250kg, 500kg, and 1,000kg. All are supposed to be over 70km+. Safran states as much that these bombs have a distance of over 70km. In-game we have the 250kg class which are lighter than the 1,000kg and 500kg variants.
Should note that Rafale International stated a demonstrated range of 80km, not that it is the maximum range for it.
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Are there any sources on the battery life of AASM, or any reason to believe 250 seconds is correct? I ask because increasing battery time would appear to be the most logical way to resolve the issue. Or at least it seems it would form part of a solution.
You have said yourself that it is “improbable” that the drag needs a significant reduction. And given the motor burns for 30 seconds of a 250 second flight time it would need to have a pretty significant thrust increase to increase the average speed of the weapon by the amount you claim.
But the point stands that currently there are no sources supporting a range of 90 km, or even anything in excess of 80 km.
Does the AASM meet its quoted low altitude range in game? If so that would support the idea that it is simply the battery life that needs extending for the high altitude range to be met. If not then it would seem some combination thrust, drag, and lift need adjusting.
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i’m pretty sure it would actually get to this range if it didn’t try to do a U turn near the end of its flight path. This kind of detour make it hard for the missile to over correct, sometimes leading to misses, and it also increases the flight distance and flight time for no good reason