A History of the Survivability Design of Military Aircraft

Abstract : In simple words, survivability in combat is achieved by not getting hit by the enemy's weapons or withstanding the effects of any hits suffered. The likelihood an aircraft gets hit while on a mission is referred to as the aircraft's susceptibility, and the likelihood the aircraft is killed by the hit is referred to as the aircraft's vulnerability. Reduction of aircraft susceptibility is achieved by: (1) the selection of the appropriate weapons, tactics, threat suppression, and support jamming for the mission, (2) reducing the aircraft's signatures, and (3) incorporating on-board threat warning equipment and countermeasures in the form of electromagnetic jammers and expendables. Reduction of aircraft vulnerability is achieved by: (1) the use of redundant flight critical components, adequately separated so that a single hit does not kill them all, (2) properly locating the critical components to reduce vulnerability, (3) designing the critical components, or adding equipment, to suppress the effects of any hits, and (4) shielding those components that cannot be protected otherwise. All of these concepts for enhancing survivability impact the design of the aircraft. The importance of survivability in the design of aircraft has varied throughout the 20th century from a total neglect to the highest priority. This paper presents the evolution of the survivability design of aircraft from the beginning of World War II to the present time.