Re Shiv, SSridhar, Kanson
I have been claiming that Brahmos 1000km missile for a long time primarily on the basis that (as per scientific papers published in USA in 1960s) range of Ramjet is 3 times the equivalent solid fueled missiles. So we have to see Brahmos as a 9 ton Single Stage Solid fueled missile. Even ATACMS with a weight of 1700kg and 250kg warhead has 300+km range. There was no way the range was only 290km for Brahmos.
Now we know that Yakhont = Russian Brahmos has a range of 450km in hi-hi-lo mode, so it should be reasonable to claim the minimum “powered” range of 600km for hi-hi-hi mode.
Now if look at articles for Ramjet missiles especially from USA in 1960s, a max height of 100,000 feet and throttable speed upto Mach4+ was claimed. (Look at SR-71, Mig-25 also)
The issue is whether the Ramjet missiles starts tumbling after the fuel is over or it is still controllable. Then the data is available for Sea dart (which is also a cylindrical missile with small fins) which shows that Ramjet missile also has additional range due to coasting, gliding etc for additional 20 knots ( around 38km) for a SAM which needs to retain more maneuverability compared to ground attack missile.
Now further we have seen that Ramjet missiles were used in 1960s as SAMs even with small fins. So we have to ask ourselves whether Brahmos can be used against enemy awacs at range of 500-700km? If Indian Awacs detect an enemy Awacs (800km) away, can it call upon a Brahmos battery? Even a “possibility” of such a course of action places tough choices upon the enemy.
Now coming to maximizing ground attack range. The issue is whether the missile has to be “powered” til it hits the target or it has coasting, gliding range even with small fins? Now I am assuming that for a static target on ground, the missile can hit it after a coasting phase and it can be controlled & will not tumble. In my theoretical scenario, If the fuel is expended at max height of 30km but the missile is oriented towards upward climb say 20-30 degrees, then due to minimal friction, how long & how high will it climb with initial speed of Mach 2.4-Mach 2.8 ?? It requires tough and complicated calculations (beyond my school boy ability) but lets take another 30km and 100km range? Thereafter it will coast back to ground all the while gathering speed & maneuvering ability? (Even Indian 1000kg bomb with only tail end fins is supposed to have a range of 30km if released from 12km at Mach 1.2) So what will be the speed, distance and terminal angle of attack? Mach 1.5, another 100km, 30-60 degrees ??
Note :- Gliding would be function of air resistance acting against the flight and also assisting the fins. Alongwith this, we have to consider the basic semi parabolic/ballistic path initially due to velocity to climb up and then due to gravity to fall down. It will neither climb straight up nor fall straight down.Basic Calculator