Regarding the engine fuel issue of the R-24 missile

[Elenta Lin]

I once heard an incredible claim that the R-24 air-to-air missile actually uses a liquid fuel called AK-27... While this sounds absurd, it's not entirely without basis, judging from some launch footage. Since the person who told me about this claimed to have lost the original technical description document, I haven't been able to verify this information. Does anyone have any information about this matter?

 

[TomS]

I once heard an incredible claim that thep R-24 air-to-air missile actually uses a liquid fuel called AK-27... While this sounds absurd, it's not entirely without basis, judging from some launch footage. Since the person who told me about this claimed to have lost the original technical description document, I haven't been able to verify this information. Does anyone have any information about this matter?

Absolutely not the case. Authoritative Russian sources clearly identify the motor as a solid fuel PRD-287 (PRD being Russian for Solid fuel rocket).

https://missilery.info/missile/r24
AK-27 is the Russian designation for a specific formulation of fuming red nitric acid, which was used as a storable liquid fuel in various rockets (like the Scud), but definitely not in the R-24.

 

[overscan (PaulMM)]

There have been rumours of at least studies of liquid fueled R-24 on some forums. I wouldn't entirely rule it out, as liquid fuel was considered for various AAMs in the West in the late 1950s and 1960s.

 

[Aeria Gloria]

It fires for 6 seconds on average or even less. What would be the reason to make it liquid fueled in such a case of a short acting motor?

 

[Colonial-Marine]

There was one early variant of the AIM-7 Sparrow, the AIM-7D I think, which had a storable liquid propellant rocket motor. So if nothing else it's feasible to do.

 

[Aeria Gloria]

According to Markovsky and a European weapon disposal catalogue, the PRD-287 is a solid fuel motor, which as mentioned PRD is the designation for solid fuel.

 

[overscan (PaulMM)]

I'm not disputing the R-24 used a solid fuel motor, the rumour was about a test variant.

 

[Sferrin]

There have been rumours of at least studies of liquid fueled R-24 on some forums. I wouldn't entirely rule it out, as liquid fuel was considered for various AAMs in the West in the late 1950s and 1960s.

AIM-47 comes to mind.

 

[publiusr]

It fires for 6 seconds on average or even less. What would be the reason to make it liquid fueled in such a case of a short acting motor?

Maybe just thumping the missile high enough to where harsher solid ignitions won’t toast the container as badly?

Get it going fast enough for airbreathing solids to kick in?