AirspeedIn aviation, airspeed is the speed of an aircraft relative to the air. Among the common conventions for qualifying airspeed are: Indicated airspeed ("IAS"), what is read on an airspeed gauge connected to a Pitot-static system; Calibrated airspeed ("CAS"), indicated airspeed adjusted for pitot system position and installation error; Equivalent airspeed ("EAS"), calibrated airspeed adjusted for compressibility effects; True airspeed ("TAS"), equivalent airspeed adjusted for air density, and is the speed of the aircraft through the air in which it is flying.
T-tubuleT-tubules (transverse tubules) are extensions of the cell membrane that penetrate into the center of skeletal and cardiac muscle cells. With membranes that contain large concentrations of ion channels, transporters, and pumps, T-tubules permit rapid transmission of the action potential into the cell, and also play an important role in regulating cellular calcium concentration. Through these mechanisms, T-tubules allow heart muscle cells to contract more forcefully by synchronising calcium release from the sarcoplasmic reticulum throughout the cell.
