Bar (unit) mb (rather than the proper mbar) to denote the millibar. Between 1793 and 1795, the word bar was used for a unit of weight in an early version of the metric system. Atmospheric air pressure is often given in millibars, where standard atmospheric pressure at sea level is defined as 1013.25 mbar, 101.325 kPa, 1.01325 bar, which is about . Despite the millibar not being an SI unit, meteorologists and weather reporters worldwide have long measured air pressure in millibars as the values are convenient. After the advent of SI units, some meteorologists began using hectopascals (symbol hPa) which are
Piper PA-24 Comanche tail, laminar flow airfoil, and all-flying stabilator. The standard fuel capacity of the PA-24-180 was . The flaps were manually actuated, controlled by the same Johnson bar actuator as the Piper Cherokee. The aircraft specifications were for cruise speeds of and fuel burns between 7.5 and 10.5 gph at 55-percent and 75-percent power settings. Full-fuel payload with standard fuel was 715 pounds, with a gross weight of and range with 45-minute reserve of 700 nautical miles. When new, standard, average-equipped Comanche 180s sold between $17,850 (1958) and $21,580 (1964). A total of 1,143 were built. In 1958 Piper introduced a