AIM-54 launch in PD STT = no active guidance? (@ DEVS) - Page 3 - ED Forums
 


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Old 04-18-2019, 09:55 AM   #21
Dudikoff
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Originally Posted by Naquaii View Post
In regards to the C, we don't have that much info as our manuals are older than the -C. If you have any info feel free to share! :-)
I think there's technically enough info to try to implement some difference between them (DCS permitting, of course).

https://forums.eagle.ru/showpost.php...&postcount=125

https://www.forecastinternational.co...fm?ARC_ID=1066

So, if I understand correctly, during the mid-course phase, the AIM-54A will periodically get messages from the AWG-9 on where to look for the reflected SARH signal and then adjust its course towards the target directly. Not sure at which interval these messages are sent, but I guess the missile will burn more energy because it will keep readjusting itself towards the target until the terminal phase where it switches either to ARH homing or SARH with PN. The interval is also different in case ARH (less frequent) or SARH terminal homing (more frequent) is used (or basically TWS or PD-STT).

For the AIM-54C on the other hand, it apparently has a digital inertial system with an autopilot so it can fly towards an optimal intercept point calculated by the AWG-9 on launch and then updated directly in case the target changes its trajectory.
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Last edited by Dudikoff; 04-18-2019 at 10:59 AM.
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Old 04-18-2019, 11:52 AM   #22
Naquaii
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Quote:
Originally Posted by Dudikoff View Post
I think there's technically enough info to try to implement some difference between them (DCS permitting, of course).

https://forums.eagle.ru/showpost.php...&postcount=125

https://www.forecastinternational.co...fm?ARC_ID=1066

So, if I understand correctly, during the mid-course phase, the AIM-54A will periodically get messages from the AWG-9 on where to look for the reflected SARH signal and then adjust its course towards the target directly. Not sure at which interval these messages are sent, but I guess the missile will burn more energy because it will keep readjusting itself towards the target until the terminal phase where it switches either to ARH homing or SARH with PN. The interval is also different in case ARH (less frequent) or SARH terminal homing (more frequent) is used (or basically TWS or PD-STT).

For the AIM-54C on the other hand, it apparently has a digital inertial system with an autopilot so it can fly towards an optimal intercept point calculated by the AWG-9 on launch and then updated directly in case the target changes its trajectory.
Problem is that both missiles have these systems, they're just implemented differently, and compared to our data on the -A a lot of the -C stuff is conjecture. In any case we're not at a stage where this makes any difference in DCS apart from numbers for countermeasure rejection and seeker performance.
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Old 04-18-2019, 12:39 PM   #23
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Originally Posted by Naquaii View Post
Problem is that both missiles have these systems, they're just implemented differently, and compared to our data on the -A a lot of the -C stuff is conjecture. In any case we're not at a stage where this makes any difference in DCS apart from numbers for countermeasure rejection and seeker performance.
Both systems have the same purpose in the end, but if e.g. my simplified understanding is generally correct, the AIM-54C would normally burn less speed during the mid-course phase and thus would have more available on the final (which would match those claims that it has some optimizations against more maneuverable targets).

In that case, perhaps some drag values could be adjusted so that on average it ends up with somewhat more energy?

I mean, what's the point of having the C in the game if it's modeled exactly the same as A is?

I'm sure HB could make a reasonable educated guess based on the data available and give it a somewhat improved performance.
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Last edited by Dudikoff; 04-18-2019 at 12:47 PM.
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Old 04-18-2019, 01:21 PM   #24
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Quote:
Originally Posted by Dudikoff View Post
Both systems have the same purpose in the end, but if e.g. my simplified understanding is generally correct, the AIM-54C would normally burn less speed during the mid-course phase and thus would have more available on the final (which would match those claims that it has some optimizations against more maneuverable targets).

In that case, perhaps some drag values could be adjusted so that on average it ends up with somewhat more energy?

I mean, what's the point of having the C in the game if it's modeled exactly the same as A is?

I'm sure HB could make a reasonable educated guess based on the data available and give it a somewhat improved performance.
AIM-54C include the command inertial system, but don't active command is from command message or inertial.
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Old 04-18-2019, 01:47 PM   #25
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Quote:
Originally Posted by Dudikoff View Post
Both systems have the same purpose in the end, but if e.g. my simplified understanding is generally correct, the AIM-54C would normally burn less speed during the mid-course phase and thus would have more available on the final (which would match those claims that it has some optimizations against more maneuverable targets).

In that case, perhaps some drag values could be adjusted so that on average it ends up with somewhat more energy?

I mean, what's the point of having the C in the game if it's modeled exactly the same as A is?

I'm sure HB could make a reasonable educated guess based on the data available and give it a somewhat improved performance.
Our -C already has different flight parameters and range compared to the -A in addition to slightly different seeker performance.

If we find reasonably trustworthy data on other paramaters which we could feasably implement we'll ofc do that.
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Old 04-18-2019, 01:57 PM   #26
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Quote:
Originally Posted by Naquaii View Post
Problem is that both missiles have these systems, they're just implemented differently, and compared to our data on the -A a lot of the -C stuff is conjecture. In any case we're not at a stage where this makes any difference in DCS apart from numbers for countermeasure rejection and seeker performance.
There must be a difference between AIM-54A and AIM-54C, because AIM-54C has ISA.
This can be confirmed in the public "APPROVED NAVY TRAINING SYSTEM PLAN FOR THE AIM-54 PHOENIX MISSILE".
https://www.globalsecurity.org/milit...ntsp/aim54.htm
The problem is to confirm how ISA works. If ISA is only used as an aid to semi-active data sampling, AIM-54C is similar to AIM-54A.
On the contrary, that would be similar to AIM-120.
"Aviation Ordinance Man 2 & 3 - Aviation theories and other practices", which regards AIM - 54C/D as semi-active midcourse guidance.
Http://navyaviation.tpub.com/14023/c...issile-108.htm
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Old 04-18-2019, 02:08 PM   #27
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I guess part of the problem here is that the late model Phoenix had technology borrowed from it for the development the Aim120. I would imagine that would make things like command guidance very problematic to acquire.
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