Fighter Combat

FIGHTER WEAPONS 59For forward- or rear-quarter threats, the effectiveness of a missile breakdepends on the target's G. Because of the usual large speed advantage of themissile over the target, a good rule of thumb is that the missile will requireabout five times the G capability of the target to complete a successfulintercept. Although the LOS rate increase is primarily a function of targetG, the time required to produce a beam aspect is dependent on target turnrate. Since the optimum instantaneous-turn-rate performance and maximumG of an aircraft are obtained near its corner velocity, it behooves thefighter aircrew to maintain at least this speed when in hostile airspace. (Adiscussion of turn performance can be found in the Appendix.) Fasterspeeds are usually not as injurious to turn performance as slower speeds,since deceleration is generally much quicker than acceleration in breakturnsituations. Turn rate and radial G may also be enhanced by breakingdownward, altitude permitting, to exploit the added G of gravity. Nosedownbreaks have the additional advantages associated with lower altitudesand increased missile look-down. If a heat seeker is suspected,however, a break toward the sun or into a cloud might be the best move.Other defensive measures (i.e., chaff, flares, etc.) should be continuedduring the break turn as long as the threat may still exist, or until additionalthreat information is received.The direction of the defensive break turn depends on the aspect of thethreat, and usually should be in the closest direction to achieve a beamaspect. For rear-hemisphere missiles this generally means breaking towardthe threat, and turning away from forward-hemisphere threats. For nearlyhead-on or tail-on threats, the break direction is the pilot's choice, withvertically nose-down usually preferable if that option is available. Particularlyfor forward-hemisphere threats, the optimum maneuver plane mayhave to be altered somewhat if the defender is to maintain sight of themissile.If a threat is detected near a beam aspect, or if a break turn succeeds inproducing a beam aspect before intercept, continuation of the break turn inthe same plane is usually not advantageous, as this would tend to rotatethe missile out of the beam region. In addition to the other possibleproblems already mentioned, the beam aspect presents the greatest LOSrate to the missile. One exception to this rule pertains if the threat issuspected of being a rear-hemisphere-limited heat-seeking weapon, inwhich case a continued turn toward the missile rotates it into the forwardhemisphere, further degrading its chances of guidance.Otherwise an out-of-plane break turn, similar to the maneuver describedfor guns defense (Figure 1-5), usually should be initiated against amissile in the beam region. This could mean an immediate upward ordownward break on missile launch warning, or an approximate 90° changein the plane of a turn already commenced. For example, if the reaction to arear-quarter threat had been a nose-low vertical turn (split-S) of about 90°,and indications were that the missile was then near the beam, an approximate90° roll should be made, followed by a pull-up. This out-of-planemaneuver should be continued, while turning toward the missile (i.e.,