A tail-chase engagement (or rear-aspect engagement) is one where a

surface-to-air missile A surface-to-air missile (SAM), also known as a ground-to-air missile (GTAM) or surface-to-air guided weapon (SAGW), is a missile designed to be launched from the ground to destroy aircraft or other missiles. It is one type of anti-aircraft syst ...

system or

jet aircraft A jet aircraft (or simply jet) is an aircraft (nearly always a fixed-wing aircraft) propelled by jet engines. Whereas the engines in propeller-powered aircraft generally achieve their maximum efficiency at much lower speeds and altitudes, jet ...

engages another aircraft while the target aircraft is flying away from the attacker. This makes engagement with

cannon A cannon is a large- caliber gun classified as a type of artillery, which usually launches a projectile using explosive chemical propellant. Gunpowder ("black powder") was the primary propellant before the invention of smokeless powder ...

s or

infrared homing Infrared homing is a passive weapon guidance system which uses the infrared (IR) light emission from a target to track and follow it seamlessly. Missiles which use infrared seeking are often referred to as "heat-seekers" since infrared is rad ...

missiles easier because of the minimal lateral target movement relative to the attacker and the fact that the hot engine exhaust nozzle(s) are pointing directly at the attacker, making the infra-red seeker's task of tracking the target much easier. Missiles typically have a very high chance of hitting a target in a tail-chase engagement because of the much reduced closure rate. If the missile is travelling at Mach 2.5 and the aircraft at Mach 1, the combined overtake rate of Mach 1.5 means that the missile should be easily able to respond to any evasive maneuvers the aircraft might perform. Missiles can typically maneuver faster than aircraft and in a tail-chase engagement the target has no real advantage over the missile. Its only real hope is to fly away from the missile fast enough that the overtake rate is reduced to virtually nil, and then force the missile to follow it through several turns, bleeding off its residual energy and causing it to fall away. It has the disadvantage, however, of meaning that any missiles or cannon rounds fired at the target must be able to reach and overtake it despite the speed at which the target is moving away. This greatly reduces the effective range at which these

munitions Ammunition (informally ammo) is the material fired, scattered, dropped, or detonated from any weapon or weapon system. Ammunition is both expendable weapons (e.g., bombs, missiles, grenades, land mines) and the component parts of other weap ...

can be used. Many

missiles In military terminology, a missile is a guided airborne ranged weapon capable of self-propelled flight usually by a jet engine or rocket motor. Missiles are thus also called guided missiles or guided rockets (when a previously unguided rocket i ...

have an effective range in a tail-chase engagement on the order of one-third or one-quarter of that in a head-on engagement. In addition, in the case of an engagement between two aircraft, the attacking aircraft will probably have to engage

afterburner An afterburner (or reheat in British English) is an additional combustion component used on some jet engines, mostly those on military supersonic aircraft. Its purpose is to increase thrust, usually for supersonic flight, takeoff, and c ...

and chase the target down, using up a lot of fuel in the process.

See also