So what is the maximum lead angle (from the boresight) where the system can still track the missile beacon in both angles?

The obvious is 3.5 degrees, but I have two confirmations already of deviation from the boresight at ~5 degrees....

Presumably the boresight can lead the target with the missile leading the boresight, at least transiently.

Consider H<5 mode...

This is a bit irrelevant, as you must use T/T or K method, so not much possibilities of big lead in epsilon....


As per more than 4 degrees lead - it could be due to unguided flight of missile (until hitting the strobs on >2.1 km range...

In Epsilon in case of H<5, the boresight is moved down electrically by 3 degrees.
If I consider +-4 degree of elevation lead from the mechanical boresight, than in H<5 the lead can be -1 .. +7 degrees from the electrical boresight.

K and T/T mode? Also not relevant for beta plane...

I have a question - which method we can use when shooting on receding target - UPR/K/TT ?

Firing Manual states...

78. Firing on receding target is allowed only if it was missed during incoming.
Receding target can be fired if its speed is less than 420m/s, and altitude is less than 25km.

79. If the parameter of the target is less than 12km, fire only after the SNR roll over.

80. prefer 20DSU missiles against receding targets.

The firing mode of the SNR, guidance method, radio proxy fuse setting should be set similarly as incoming target.
K3 method cannot be used.

I've been told that system goes in T/T automatically no matter which method was selected.... Could we check this with FCO????

According to the Firing Manual you can select UPR, K, TT, I87V.



PS: checking with several FCO's

There is a bit difference between selecting and executing... (as automatic switching in T/T when target starts to dive)... As D and P are different because of the missiles, and same for all mentioned methods - I think that system uses only one of them, no matter of selection...

The table above shows target altitude Hc=0.1km and max engagement range Dt=24km.

You cannot engage target at H=100m at 24km distance with TT method.
With TT if the target is at 24km, minimum altitude is 1km!

See, if the target is receding, it moves in epsilon plane as like it is diving to earth (on approaching target) (so no UPR allowed). Only K and T/T left....

Where you got that?

I checked this topic with several exBattery FCO's.

In our S-75M2, S-75M3, and S-75M3OP batteries, the guidance system would not select different guidance method than it was set by the FCO.

OK, I just wrote to some veterans in a forum, and they told some different stuff...

Also I have been told that up to 420 m/s target speed, UPR and T/T method behave at same way....

Another question - do we have at SIM method T/T + E?

You are goofed.


Ask for documentation prooving these claims.


ps: T/T + exponentially decreasing elevation (against missile-target range) is real for descening planes in case of H<5 is switched.

In data you provided, the zone is the same for K; T/T i T/T-87...

The table above shows target altitude Hc=0.1km and max engagement range Dt=24km.

You cannot engage target at H=100m at 24km distance with TT method.
With TT if the target is at 24km, minimum altitude is 1km!

Did you read it earlier?