R-40 AAM

[overscan (PaulMM)]

PARG-12-VV seeker from the R-40R.

Missiles.ru

 

[lewradar]

another inverse cassegrain antenna: they really loved those

 

[AHMAD RUSHDI]

Gentleman,
I had the opportunity to work on the R-40R missile. To study the missile one has to put it into its context. The time frame it was designed (early 1960s) and its intended target (B-70 and later B-52s, B-1). It was a great missile; a lot of experience was put into it. The Inverse Cassegrain antenna was one ECCM feature. Other features I can remember were: selection of the radar frequency (of the carrier aircraft), the radar frequency of the carrier aircraft is used to tune the local frequency generator of the missile receiver. Another feature was the selection of the pulse repetition frequency (PRF). Another feature was the selection by pulse duration. All of these operations would take place before the missile homing head locks on the received signal retarding from the target aircraft. It is now clear that there were no change in the radar mode of the carrier aircraft when the missile is launched. This would make the target unaware that a missile is launched towards it.

 

[TinWing]

Gentleman,
I had the opportunity to work on the R-40R missile. To study the missile one has to put it into its context. The time frame it was designed (early 1960s) and its intended target (B-70 and later B-52s, B-1).

By all appearances, the Soviets were still working on a response to the high speed, high altitude bomber threat that no long existed in 1962. The Avro 730 had been cancelled in 1957 and the B-70 program was dying even before the Kennedy administation took power. The Skybolt air launched ballistic missile was still very much alive in 1962, and it should have been clear to the Soviets that the true threat was from standoff weapons delivered from low flying platforms.

Had the Soviet caught wind of the SLAB or Subsonic Low Altitude Bomber program that suddenly appeared in 1961? Apparently not?


It is equally important to note that the contemporary Lockheed YF-12 was intended primarily for the look down/shoot down role against low flying aircraft - quite a stark contrast to the MiG-25.

 

[AHMAD RUSHDI]

I dont think that we should view every armament development as action and reaction. The Soviet Union has developed a major weapon system, Mig-25/ R-40 combination with unique features. If the US threat dissappeared should the soviets throw the Mig-25 into the trash bin. The soviet threat to aircraft carriers dissapeared after 1991, should the US Navy throw its Aegis sytem into the wastepaper basket?
I think the Mig-25 has proved itself, look at the amount of the effort put by US/NATO to counter it

 

[TinWing]

I dont think that we should view every armament development as action and reaction. The Soviet Union has developed a major weapon system, Mig-25/ R-40 combination with unique features. If the US threat dissappeared should the soviets throw the Mig-25 into the trash bin. The soviet threat to aircraft carriers dissapeared after 1991, should the US Navy throw its Aegis sytem into the wastepaper basket?
I think the Mig-25 has proved itself, look at the amount of the effort put by US/NATO to counter it

The United States did throw the YF-12/AIM-47 combination "into the wastepaper" basket, despite the relative success of the firing trials and successful development program? Why? Intelligence indicated - quite correctly - that the Soviets would not produce a low flying, supersonic bomber that would necessitate the YF-12/AIM-47 as a counter.

Open sourced intelligence available by 1962, in other words "public information," should have similarly indicated that the United States and Britain would not produce a high level, high speed bomber threat to the Soviet Union. Similarly, the low level operating doctrines practiced by the NATO powers from the mid-1950s - in response to the Soviet SAM threat - were public knowledge.

It is indeed true that the United States misinterpreted both the mission and the capabilites of the MiG-25/R-40, but I seriously doubt that Soviet intent was to produce this conceptually compromised or fundimentally flawed weapons system solely for purposes of misinformation and deception?

 

[Fox_One]

All of these operations would take place before the missile homing head locks on the received signal retarding from the target aircraft. It is now clear that there were no change in the radar mode of the carrier aircraft when the missile is launched. This would make the target unaware that a missile is launched towards it.

About radars, I am no expert, but AFAIK the launch of a SARH missile is detected by opponent's RWR gear because of the illumination signal. I saw on this forum that MiG-23M izd 323 radar have a separate illumination horn included in the combined irradiator. But later designs like N-019, -001 don't have this feature, they use the same irradiator sending one pulse for angle error/range/closure velocity, then one pulse for illumination and so on. Also the illumination pulses can be frequency-modulated in the case of R-27R/ER and in this way the radiocorrections are send to the missile.

Now here comes my question, I hope it doesn't sounds silly.
What about if the radar after achieving the lock immediately switches on the illumination, even if there is not yet any missile launched? Is it this how is actually done in reality? In this way the adversary will not know the precise moment of launch. Also in the before launch intercept phase false radiocorrection can be sent, to make everything look realistic, so when the missile is launched nothing will really change. Sure, the enemy knows from intelligence your Drmax1 and Drmax2, but not knowing precisely the moment can be important.
Precisely, how the mechanism actually works let's say when a F-15 detects that a SARH missile was launched towards it? Precisely how the RWR knows?

 

[AHMAD RUSHDI]

This is a good suggestion from the deception (EW) point of view, but the aircraft illuminating the target will have no idea about the general air situation because its radar has switched to a narrow illuminating pencil beam. This is pretty dangerous.
The Mig-25 P and PD/PDS didnt switch its radar to illumination mode , there were none. the radar kept on working in a pulse mode, the adversary had no idea that a missile was launched unless it was visually detected or using a MAWS.

 

[crossiathh]

... Other features I can remember were: selection of the radar frequency (of the carrier aircraft), the radar frequency of the carrier aircraft is used to tune the local frequency generator of the missile receiver. A

Where is the wave guide located which feeds the radar signal into the missile to tune the missile's frequency generator?
Just for the comparison the antenna at the tip of the APU-23M missile carrier of a MiG-23.

Do the R-40R and R-40RD have rear antennas like the R-23R/24R and do they doppler processing.
Furthermore, I thought the R-40RD seeker evolved from the RGS-24 seeker of the R-24R. This was using a continuous wave signal.