Crashworthiness is the ability of a structure to protect its occupants during an impact. This is commonly tested when investigating the safety of aircraft and vehicles. Different criteria are used to figure out how safe a structure is in a crash, depending on the type of impact and the vehicle involved. Crashworthiness may be assessed either prospectively, using computer models or experiments, or retrospectively, by analyzing crash outcomes. Several criteria are used to assess crashworthiness prospectively, including the deformation patterns of the vehicle structure, the acceleration experienced by the vehicle during an impact, and the probability of injury predicted by human body models. Injury probability is defined using criteria, which are mechanical parameters that correlate with injury risk. A common injury criterion is the head impact criterion (HIC). Crashworthiness is measured after the fact by looking at injury risk in real-world crashes. Often, regression or other statistical methods are used to account for the many other factors that can affect the outcome of a crash.
Airbag on a Bell OH-58 Kiowa helicopter
Sikorsky UH-60 Black Hawk
The Sikorsky UH-60 Black Hawk is a four-blade, twin-engine, medium-lift utility military helicopter manufactured by Sikorsky Aircraft. Sikorsky submitted the S-70 design for the United States Army's Utility Tactical Transport Aircraft System (UTTAS) competition in 1972. The Army designated the prototype as the YUH-60A and selected the Black Hawk as the winner of the program in 1976, after a fly-off competition with the Boeing Vertol YUH-61.
Sikorsky UH-60 Black Hawk
The flyoff competition in the mid-1970s between the Sikorsky YUH-60A (in front) and Boeing Vertol YUH-61A prototypes
UH-60A Black Hawks over Port Salinas during the invasion of Grenada, 1983. The conflict saw the first use of the UH-60 in combat.
UH-60s equipped with M60 machine guns near An Najaf, Iraq, May 2005.