Could straight up be lying as well, I personally would not be surprised about the levels of misinformation on the utmost modern missile stuff.
The lying would be downsizing the level of performance of the missile.
The french have been known to downplay a lot the characteristic of their equipment.
The SCALP/ Storm Shadow was given for 250km range before the RAF gave up that it had more than 500km range.
The 30% more is probably a conservative estimate on the real upgrade of the missile.
There has been more than 20 years between the MICA and the MICA NG.
In this time there have been a lot of advancement in propelant chemistry, motor tech, electronic size (more propelant), better trajectory…
The AIM-120D manage a 50% range upgrade over the C7 only with a better fligth profile (the motor remain unchanged with the C7).
The claimed 130km range for the MICA NG EM seems plausible and so is the 40km from the VL-MICA NG
Could it have been possible that the AIM-120D has same motor but increased propellant mass?
The AIM-120D-3? has a dual pulse motor; (Source)… The DTIC document cites this source for the dual pulse motor on the AIM-120.
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Further, the weight is no more than 345 pounds for AIM-120C-7 lot 27+. (Source)
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Seems they replaced the “SCAS” (Shortened control actuator section) with a “value control actuator section” after lot 27 of the AIM-120C-7 which reduced weight from 350 pounds to approximately 344 pounds and the AIM-120D estimate was 345 pounds. Not sure if I’m understanding that document correctly.
Either way, it has been rumored that the AIM-120D has a dual pulse motor and that is what yields the additional range which would make sense. It is ridiculous to assume that only a loft trajectory could increase overall range by 50% when it already had a lofting trajectory to begin with.
Likely, Adrien was citing this source that states the current AIM-120D variant (likely D-3) improved the kinematics of the AIM-120D with updated guidance principles / software. It can be easy to confuse these very nondescript sources as they are so for a reason.
More glaringly, the AIM-120D has “increased range over previous variants” as shared by a primary source…
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According to ATK Alliant Systems in 2009, they won a contract to develop multi-pulse motors for the AMRAAM. This was expected to be complete in 2013, but as we know this was delayed due to reliability issues with the (then) AIM-120C-7+ motors at very cold temps.
In response a interrim motor was developed with the Swedish firm NAMMO to supply the AMRAAM until the AIM-120C-7+ could receive the improved rocket motors. Presumably, this would have been the improved rocket motor and retrofit the dual pulse model onto earlier missiles using the “VCAS”. Don’t really have any proof of this yet though, so take it with a huge pinch of salt.
We talked about the fact that the AIM-120D had or not a dual-pulse motor with @DirectSupport on discord and we found multiple source saying that the motor was in fact NOT a dual pulse.
I originaly thought that the AIM-120D in fact did use a dual-pulse motor to achieve that 50% range upgrade but apparently not.
I’ve read that Raytheon proposed a dual-pulse missile but it wasn’t adopted for production.
We’ll have to see if @DirectSupport has some source that says the contrary.
The dual-pulse range would be in fact logic.
The MICA NG a 112kg missile manage 130km range. (Dual pulse confirmed)
The AIM-120D a 154kg missile manage 160/180km range. (Dual pulse maybe)
The PL-15 a 200/230kg missile manage a 200km+ range. (Dual pulse confirmed)
And heavier missile mean more propelant mass and so better range.
The AIM-120D managing 180km without dual pulse would indeed be very strange.
or the range improvements are inflated
I would defer to Mig23M since he has access to documents that I do not.
They straight up lie about AMRAAM information at times, that is certain.
If the AIM-120D has indeed a dual pulse motor the 50% range upgrade wouldn’t be unimaginable
But if it does not then yeah, i can’t see that 50% number be true.
Why would they be lying tho, would’nt look good on the international market.
Or the 50% range increase was when an SR-71 fired the missile at mach 3 at 90000feet against a opponent doing mach 2 at 45000feet.
Tbf the max range on those missile has no sense what so ever when we don’t know in whitch condition they are fired (10k meter or 15k meter) (Mach 1 or Mach 1.6 aircraft) and so on.
Hello everyone.
So, I’ve been working on programming a basic physics engine to test straight line missile range and it’s good enouth to do somewhat accurate modeling as far as I can tell.
One limitation at the moment is that I don’t model AoA drag so I can’t simulate manoeuvers.
This means the additional drag a missle would experience towards the end of its trajectory by increasing its AoA in order to maintain level flight is not modeled.
To compensate for this the missile is considered to be at the end of its trajectory either when speed drops below mach 0.9 at low altitude (so it still has the energy for one final high energy manoeuver) and below 110 m/s IAS (or 400kph IAS) at high altitude where the thin air means the target cannot manouver nearly as hard.
I modelled the MICA using the data from the Czech Republic and the MICA-VL launch video from this post from DirectSupport :
I slightly tweaked the sustainer burn time according to the video (so 2.75s booster time + 2.75s sustainer time) with the same total energy from the Czech document.
I ran both versions against each other and the difference in range is negligible.
Here are some of the results I got :
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When launched from a standstill at sea level the missile reaches a range of 22km before the speed drops to below mach 0.9 (still enouth energy to catch a slow manoeuvering target).
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The missile starts to reach its marketed range of 80 km with decent energy remaining from about 9000m of altitude when launched at mach 1.
It takes 120 seconds to get there so we can guess the battery would need to last at least that long.
I also modeled the MICA NG with an additional booster which provides an additional 30% of energy.
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When maunched at mach 1 at 9000m, when the booster is triggered at the last moment (when normal MICA gets slow) the booster gives just enouth energy for the missile to reach a little over 110km and it takes 135s to get there.
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When launched from a standstill at sea level and using the same trigger condition for the booster, the missile reaches a range of only about 33km.
I only managed to make the missile reach a range of 40km by triggering the booster once the speed dropped to mach 0.6, at which point it would pretty much be falling out of the sky.
My guess Is the MICA NG VL uses energy from the initial burn to get to thinner atmosphere where it will burn the additional fuel and take advanatge of the reduced drag to cruise until it gets close to its target.
Let me know if you have suggestions to make this thing more accurate or if you want me to model some other missiles :)
Also I can do missile races to see which one has the best speed or range.
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Does your engine model/take into account base drag?
Yes I do !
For the drag what I’ve done is this :
I use an approximation of the G6 standard projectile drag curve.
It’s normally used for ballistics of bullets and artillery projectile, but here I’ve used it as an approximation of the shape of a missile (I also implemented G1 and G7 drag curves so I can switch easily). (BTW I used the G6 curve for the MICA)
On top of this my approximation of the drag curve is biased towards higher drag coefficients along pretty much the whole curve.
This bias helps somewhat compensate for the fact that I don’t take the drag of the fins into account.
Now for base drag :
I wasn’t able to find much experimental data on this and doing the math is way out of my skill set.
So instead I took one paper that looked at how base bleed devices help reduce the drag of artillery projectiles.
In this paper they found that base bleed can reduce the drag coefficient of the projectile by 13% along the whole curve.
I implemented this as a 13% reduction of drag coefficient whenever the missile is burning fuel.
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Pretty interesting work around! Good job. I do think it’ll likely be a decent way to go about it for planar finned missiles and 13% reduction during motor burn is likely actually on the conservative size.
Very nice simulation you got there.
The 30% increase for the MICA NG is probably a very conservative estimate since the missile got :
- An increase in propelant mass (reduction of electronics size)
- Improvement in propelant/motor technology (the initial MICA is 20 years older than the NG one)
- New propulsion with dual pulse instead of only a boost+sustainer. This tech is new and that’s why you find it only onto last gen missile (PL-15/I DERBY ER/ AIM-120D)
For reference the AIM-120D only upgrading to a dual pulse manage a 50% range increase over the AIM-120C7. (Not taking into acount the GPS thing)
From other source the MICA NG EM is said to have a 130km max range while the MICA NG IR is said to have a 100km max range. (Air et Cosmos Spécial Rafale F5). So compared to the 80 and 60km max range of those missile you get a 66% increase in range compared to the 30% mentionned.
You should try your simulation again but with those numbers
Perhaps the limiting factor ends up being battery time which isn’t a limitation with VL situations
Since the Air and Cosmos acticle mention a 130km max range i feel like this IS the max range where the battery still function.
If you go high enouth the battery will always be what limits the range.
For example if you launch a Super 530D at 15 000 and mach 1, the missile will have the energy to travel about 87km.
In reality it will self-destruct at 59km after running out of battery.
The worst exemple of this I’ve seen so far is the R-27ER.
In the same scenario it can travel 131km but runs out of battery at 72km. (intentional nerf ?)
Sadly, range figures without context are of no use.
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nope missile just had a 60 second battery life IRL, used same battery as all the other R-27s
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