AIM-9X Seeker Cooling
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Hi,
is there a limited time the Seeker of the AIM-9X will be cooled ?We expirienced that in a long lasting Mission (+2 hrs)
At the end of the Mission there was a AA engagement. After the Lauch of the last AIM-120 the System swiched automaticly the the AIM9x.
10 minutes later we had only the growling sound of a warm Missile, unable to cool them (manually and DGFT Override) and the missiles couldnt be launched.
Same happend to my wingman.
Never experienced that before.
I´m not shure if i switchted to the Dogfight/ or Missile Override mode for a few seconds in the first 30 min of the mission (after Boresighting an AGM-65) -
It definitely sounds like you ran out of seeker head coolant. Presumably, AIM-9X cooling limit is 90 min in BMS [BMS-Training.pdf Ch 17.1, pp. 168].
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It definitely sounds like you ran out of seeker head coolant. Presumably, AIM-9X cooling limit is 90 min in BMS [BMS-Training.pdf Ch 17.1, pp. 168].
Thanks for the hint.
But that left some Questions:
When will the 90 minute Countdown start, after firing up the Jet or switching the Seeker to “Cool”
will the time run only when the Missilies are in "cool"status ?Another Question
Found this on the Net:
WIKI: AIM-9X also includes an internal cooling system, eliminating the need for use of launch-rail nitrogen bottles (U.S. Navy and Marines) or internal argon bottle (USAF).
https://en.wikipedia.org/wiki/AIM-9_Sidewinder#AIM-9X
https://www.militaryaerospace.com/sensors/article/14179064/missiles-aim9x-airtoair
https://www.reddit.com/r/hoggit/comments/a1i1od/aim9x_sterling_engine_seeker_cooling/Guess that is maybe not implemented in BMS
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AIM-9X is closed cycle nitrogen into an engine, not open cycle argon like AIM-9L/M and any limit to X-model cooling is not related to duration of any consumable. https://www.yumpu.com/en/document/read/4020560/7052-split-stirling-linear-drive-cryocooler-cryogenic-raytheon
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Hi,
is there a limited time the Seeker of the AIM-9X will be cooled ?We expirienced that in a long lasting Mission (+2 hrs)
At the end of the Mission there was a AA engagement. After the Lauch of the last AIM-120 the System swiched automaticly the the AIM9x.
10 minutes later we had only the growling sound of a warm Missile, unable to cool them (manually and DGFT Override) and the missiles couldnt be launched.
Same happend to my wingman.
Never experienced that before.
I´m not shure if i switchted to the Dogfight/ or Missile Override mode for a few seconds in the first 30 min of the mission (after Boresighting an AGM-65)This is an interesting question in more ways then one, how BMS is modeled…
You would think that the time starts when you start the cooler, like Mav battery life. But, it occurs to me I’ve never turned on IR cool, and never had problems with firing a 'Winder! I just went in’pit, and the cockpit display does default to warm. So, should 'Winders even fire? -
They will always fire, but at what range and aspect is questionable. … sensor will always “see” 500-700C of exhaust pipe, at fairly reduced range.
Whenever you switch to DGFT , computer will start cooling automatically , just need to remember to switch it back to warm to save coolant.
If you manually switch avionics to AA mode and select aim9’s , then you must start cooling manually.
(I)IR is totally different ball-game , whole shitload of factors , time of year, day, speed, height, sensor into the sun or ground,… local ambience , climate, rain, fog… you name it…
Imagine WARM aim9M shot to a eg, helicopter , not so hot target, in situations: low fast summer noon AND high alt winter night … so from +40C to -40C of temp ambience.
Low and fast air friction will heat the airframe and also missile heads more then at 20-40k of altitude. -so, your target heli will be seen on sensor at ~2nm VS ~4nm in other case.
It is all in the contrast, . as soon you blend in surroundings , you’re invisible … like vertical notch to a radar.(remember that Syrian “Fitter” who dodged 9X … so 1st/2nd gen fighter april fools 5th gen missile like a b… - so in the end they needed another 5th gen A120 for same bucket … both missiles cost more then one Fitter) - so its not a shame if you’re shot down by a Mig21 in BMS :mrgreen:
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This is an interesting question in more ways then one, how BMS is modeled…
You would think that the time starts when you start the cooler, like Mav battery life. But, it occurs to me I’ve never turned on IR cool, and never had problems with firing a 'Winder! I just went in’pit, and the cockpit display does default to warm. So, should 'Winders even fire?There is no Maverick “battery life”. Maverick is connected with a power cable to the airplane. The only battery power is when the launch button is pressed, same as JDAM. The 30/60min thing is about heat.
Yup. DGFT + MA is automatic cooling anyway. You can fire a warm missile and even hit. Cooling IR detector is about signal to noise ratio. Hot sensor is lot of noise but if signal is strong enough.
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i think it’s not modeled
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There is no Maverick “battery life”. Maverick is connected with a power cable to the airplane. The only battery power is when the launch button is pressed, same as JDAM. The 30/60min thing is about heat.
Yup. DGFT + MA is automatic cooling anyway. You can fire a warm missile and even hit. Cooling IR detector is about signal to noise ratio. Hot sensor is lot of noise but if signal is strong enough.
So the training manual is wrong?
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Yes, as I understand how the RL missile operates…yes, there is an umbilical connection to the launcher/jet…however…yes - there is a thermal battery in the missile which can be run down.
…and I’m talking about AGM-65.
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The thermal battery has a lifetime measured in seconds. It’s only broken when launch occurs.
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…if that’s true, the missile would never make it to a target. Not from the ranges I Rifle at.
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So, how many seconds your Maverick travels ?? Stevie///
Whole bunch of missiles , and nuclear bombs are/were using thermal batteries. (mostly anything with some sort of guidance, and without power-gen)
… let me enlighten you
Thermal batteries are one-shot electrical power supply for variety of use, they were used even since 1943/44 by Nazis in V2 missiles , ya know , Battle for Britain, London bombardment.
They are essentially compound of separated chemicals closed in one package , broken on launch they mix and thus create limited time chemical battery… high voltage/current/long time … you name it , depends of use.
In case of Mavericks , you certainly don’t need 180 seconds of electricity…
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By seconds I mean like within 200 sec, you know a flight time’s worth, launch to target like a JDAM. It’s certainly not an hour.
AGM-65 Maverick Umbilical Connector
Is at aft end of missile and mounted at top of the HAS or PAS
Allows aircraft to supply power to the missile before launch and the missile communicates with the aircraft
Umbilical Adapter (CPI) used to connect missile to the launch rail or to test set
CPI comes with each missile and should be tested as one unit togetherApparently the control surface power comes from pneumatic or hydraulic batteries.
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Yes - I know how thermal batteries work…and in some munitions you can also freeze them by flying at too high an altitude for too long and then the weapon can fail to function at all. Problem with a training round I know of.
If I fire long >7 miles they may fly for 20 seconds (or more - I’m generally too busy managing sensors to watch TTI), and that can vary greatly between firing level or firing in a dive…in general if I dive I end up closer. But they kill the tank as long as I don’t pedestal the target (which is also easy to do because you can fly faster than the missile). I do this in a RL Trainer, not BMS - and with LMAVs.
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Well, all I could find in the Dash-34 is the 60/30minute cumulative time per mission (inc 3min spool up) for powered up/video on. So, for that reason, I power Mav’s at Fence-In.
As for the 'Winders, I bet White_Fang was right about warm/cool. I was just “lucky”. Needless to say, IR COOL is now also in in Fence In -
Great conversation! Love it!