Work on the R-77 began in 1982 and was considered quite significant and secret since it represented Russia's first fully multi-purpose missile for both tactical and strategic aircraft for fire-and-forget employment against everything from hovering helicopters to high speed, low altitude aircraft. Gennadiy Sokolovski, General Designer of the Vympel Design Bureau, said that the R-77 missile can be used also against medium and long range air-to-air missiles such as the AIM-120 AMRAAM and AIM-54 Phoenix as well as SAMs such as the Patriot. It can also be used against cruise missiles and even precision-guided munitions (PGMs). First seen in 1992 at the MosAeroshow '92, the R-77RVV-AE was immediately nick-named Amraamski by Western journalists. The Russian-language version of the acronym for the weapon is RVV-AE and is also known as the Izdieliye-170. The missile can also be used from internal carriages where the control fins and surfaces will fold flat until it is catapulted clear of the aircraft for motor ignition.
The aerodynamics are novel, combining vestigial cruciform wings with tail control surfaces of a lattice configuration. Each surface consists of a metal frame containing a blade-like grid assembly which combines a greater control area, and thus lifting force, with reduced weight and size. The development for this control concept took three years of theoretical work and testing. Referred to by the Russians as gas dynamic declination devices, these surfaces require less powerful actuators than conventional fins, and have a lower RCS. The flow separation which occurs at high angles of attack enhances the it's turning ability, giving the missile a maximum turn rate of up to 150ยบ per second. During the initial flight phase after launch, the missile is controlled by an inertial auto pilot with occasional data link updates from the launch aircraft's radar on changes in spatial position or G of the target. During the terminal phase, the missile shifts to an active-radar mode.
Over short distances, the missile will launch in an active mode. The host radar system maintains computed target information in case the target breaks the missile's lock-on. If the seeker is jammed, it switches automatically to a passive mode and homes on the source of jamming. Development trials have been completed, and the missile is now entering production for use on aircraft such as the Mig-29, Su-27 and Mig-31. Fired against high-altitude non-manoeuvring targets approaching head-on, the R-77RVV-AE has a range of 100 km, with the seeker locking on at around 20 km, and a maximum speed of Mach 4. At short range, it can engage targets manoeuvring at up to 12g.
There are other variants under development. One has an up-rated motor which is intended to boost range at high altitudes to as much as 160 km and is known as the R-77RVV-AE-PD. The 'PD' stands for Povyshenoy Dalnosti, which in Russian means Improved Range. This variant has been test-fired and uses a solid-fuel ramjet engine. Its range puts it in the long-range class and is equivalent to that of the AIM-54 Phoenix. In another version of the R-77, a terminal infra-red homing seeker is offered. The use of IR tracking in the terminal mode might be logical because at extended ranges the data link between the launch fighter and the missile might be interrupted, or the host radar may not detect jamming. It has a laser fuze and an exploding rod warhead that can destroy the variable sized targets from missiles and PGMs to bombers.
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