Air transportation has an overall outstanding safety record. However, accidents do occur. If an aircraft is unable to stop within the runway length, the incident is described as an overrun. To provide passenger safety during an overrun, the Federal Aviation Administration (FAA) requires airports to have a 305 m (1000 ft) runway safety area. At airports that are unable to satisfy this requirement, because of either natural or man-made barriers, the FAA allows the use of a shorter runway safety area with a properly designed arrestor bed. A sensitivity analysis is presented in this paper to investigate critical parameters in the design of an engineered-materials arrestor system (EMAS). A single arrestor-bed configuration is used as a base case for considering a low-density concrete EMAS material. Five aircraft types are considered, ranging from 51,700 kg (114,000 lbs) to 322,100 kg (710,000 lbs) maximum-certificated takeoff weight. These aircraft types include aircraft with various landing-gear configuration...

The story of the army's role in Turkish politics between the 1920s and the 1950s is here divided into three phases. During the first phase, between 1923 and 1926, Atatürk succeeded in establishing his personal dominance over the political system by overcoming challenges to his authority by several of his fellow military commanders. After 1926, the army's loyalty to the regime was secured, and it played an important role in Atatürk's nation-building program. This period of symbiosis between the military and the political regime lasted until 1950, when the victory of the Democrat Party opened up a third phase, culminating in the coup d'état of May 27, 1960.

(2022). Turkey’s energy dilemmas: changes and challenges. Middle Eastern Studies: Vol. 58, Special issue in honour of Sylvia Kedourie, pp. 452-466.

Over the last 50 years, Turkey's electoral system has been subjected to frequent changes. It is still the subject of controversy, since it has significant effects on the functioning of the political system. Following the introduction of a form of proportional representation in 1961, its most controversial feature is the provision that no party winning less than 10 percent of the national vote is entitled to any seats in parliament, which has been applied since 1983. The effects of this were particularly striking in the 2002 elections, in which only two parties exceeded the threshold. In 2007 it also appears that it heavily influenced the voters' choices, with a significant flow of votes away from the small parties towards those which were expected to exceed 10 percent. Small parties also took steps to evade the threshold, either by trying to form alliances with their bigger rivals or by running their candidates as nominal independents, to whom the 10 percent rule did not apply. Further changes to the system can be expected as part of the new Constitution, which is expected to be enacted in 2008. The conclusion is that some important changes may be emerging in the structure of the party system, partly arising from a more realistic appreciation of the effects of the electoral system on the likely result by both voters and parties.