Because there are only certain areas under aircraft departure and approach paths from which missile launches are likely to be successful, surveillance of airports by security services is not as daunting as it might appear. In addition, a direct hit by a SAM does not necessarily spell disaster for an airliner. Damage may be limited to the engine itself and the structure in its immediate vicinity because the warheads only carry 1kg (SA-7) or 2kg (SA-14) of explosive, so the pilot may be able to minimise casualties by landing or force-landing the aircraft. Of the 27 civilian and 16 military transports known to have been hit by missiles in the last 25 years, there were at least five in which there were no on-board casualties and several more in which there were some survivors. However, pilots cannot successfully manoeuvre to avoid a heat-seeking missile if it has locked on to their aircraft, and throttling back on power will not deter the weapon either as it fixes on to the infrared signature of hot engine parts rather than the exhaust plume.
Source: Flight International