[Llarry]

A bit on U.S. aircraft-launched rockets.

As far as I know, aerial rockets initially came into use to attack German submarines in 1942-43. The initial model was a 3.5-inch diameter rocket that was fired from a rail on the TBF/TBM Avenger torpedo bomber flown from escort carriers in the Atlantic. Use soon spread as well to the Pacific.

The 3.5-inch rocket was considered to lack enough explosive punch and a revised "5-inch" rocket with a larger warhead, but the same rocket motor, soon was used. That was supplanted by a rocket with a larger motor that was 5 inches in diameter over the entire length called the high-velocity aerial rocket (HVAR).

The ultimate WW2 rocket was a Navy project called the Tiny Tim. This was an 11.75" diameter rocket that was effective against bunkers and the like in the Pacific late in the war. The rocket motor damaged the launching aircraft when launched, and so a lanyard was added: the rocket was dropped and the motor ignited several feet below the launching rack.

In the 1950s, air-to-air rockets came into vogue. The ultimate rocket-firing fighter was probably the Northrop F-89D Scorpion, which carried 104 2.75-inch folding-fin rockets in wingtip pods. The 2.75-inch folding fin rocket could also be fired from a pod with either 7 or 19 rockets. Ultimately the air-to-air rocket fell out of favor due to poor accuracy and the availability of air-to-air guided missiles. From the 1960s, the same rocket pods were used on helicopters to great effect.

A nuclear-tipped rocket armed USAF interceptors for some years. The Genie was unguided but of course lethal to bomber formations with its nuclear warhead.

The ultimate rocket was the Zuni, which was similar to the 2.75 but enlarged to 5-inch diameter. It was normally fired from a pod with four rockets; the larger motor gave it speed of over twice the speed of sound.

A more recent development is a new-generation 2.75-inch rocket, the Hydra-70 and some of those can be laser-guided for much improved accuracy. Generally 2.75s are used on helos and high-performance aircraft no longer use rockets.