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AIM-260

TomS

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Potential for "Have Dash III"
I'd say so. As long as the overall shape fits inside an AIM-120D "box" there's no reason you couldn't design a missile with a trapezoidal fuselage relying on body shaping for lift. Sounds like a way to get more usable volume in the same OML, at the expense of extra wetted surface and probably extra structural weight.
More usable volume is probably dependent on your propulsion system. A solid motor is always going to be cylindrical so anything outside that is going to be wasted space, more drag, more weight.
True. Thinking about advanced propellants like gels. That lets you play with throttling or even stopping and restarting motors as desired rather than according to a pre-specified schedule. There have been rumors about gels in AIM-120D already.
 

BDF

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True. Thinking about advanced propellants like gels. That lets you play with throttling or even stopping and restarting motors as desired rather than according to a pre-specified schedule. There have been rumors about gels in AIM-120D already.
Gel fueled rocket motors were speculated before the -120D was introduced. I believe unclassified docs have since shown that the 'D uses the same motor as the 'C7.
 

BDF

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More usable volume is probably dependent on your propulsion system. A solid motor is always going to be cylindrical so anything outside that is going to be wasted space, more drag, more weight.
One could potentially utilize the volume around the motor created by the aero-shape for packaging guidance, actuators, batteries etc. though. That way you extend the length of the motor for added range or speed.
 

sferrin

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True. Thinking about advanced propellants like gels. That lets you play with throttling or even stopping and restarting motors as desired rather than according to a pre-specified schedule. There have been rumors about gels in AIM-120D already.
I used to have a timeline, decades ago, that showed AIM-120 planned improvements. Gels were in there but I wonder if it was a fad that has faded. To my knowledge no missile in service, anywhere, uses gel fuel. Wonder if when it's all said and done gel doesn't have enough bang for the buck.
 

Grey Havoc

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To my knowledge no missile in service, anywhere, uses gel fuel. Wonder if when it's all said and done gel doesn't have enough bang for the buck.
I think that it has been cost and production considerations which have held back the technology.
 

sferrin

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To my knowledge no missile in service, anywhere, uses gel fuel. Wonder if when it's all said and done gel doesn't have enough bang for the buck.
I think that it has been cost and production considerations which have held back the technology.
Consider all the moving parts, the space and weight they take, and the cost/reliability hit they impose. And they don't really deliver a huge bump in ISP. Better than solid, sure, but not to the levels of liquid propellant. And you lose volume that could be used for propellant for the hardware to pressurize and feed the gel into the combustion chamber. . . IIRC the latest edition of Sutton's book doesn't even cover gel fuels. I had an earlier edition and bought the newest one (well, newest a year or two ago) to see what progress had been made in gel fuels and it didn't even cover them. They had been removed.
 

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Didn't the Meteor get a gel fuelled throttable engine from Bayer-Chemie?
 

TomS

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Didn't the Meteor get a gel fuelled throttable engine from Bayer-Chemie?
The Meteor VFDR is solid-fuel. I suspect they looked at a gel option (I see a paper out there that seems to evaluate gel in a very Meteor-like missile) but I don't see anything to suggest they actually changed over.
 
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