NIFE AERO QUESTIONS AND ANSWERS RATED A+

NIFE AERO QUESTIONS AND ANSWERS RATED A+ What is a vector? direction and magnitude What is air density? Total mass of air particles per unit volume. m/v What is a moment? Force that is moved some distance. What are the requirements for an airplane to be in equilibrium flight? Sum of all forces and all moments around the center of gravity are equal to 0 Can equilibrium flight be achieved in a turn? No. Acceleration is occurring. There are moments What are the requirements for an airplane to be in trimmed flight? Sum of moments around the center of gravity must equal 0 What remains constant in trimmed flight? Aircraft attitude Can trimmed flight be achieved in a turn? Yes What is the relationship between temperature and air altitude? How man degrees per how many feet? And what is it called? Air temp decreases linearly with an increase in altitude at 2C per 1000 feet, until 36000 feet. Average lapse rate What is a streamline? Path air particles flow in steady airflow What is a streamtube and what kind of system is it? Collection of many adjacent streamlines. Closed system What is the relationship between humidity and air density? Humidity increases, density decreases What is the General Gas Law? P=pRT (variation of PV=mRT When does steady airflow occur? When static pressure, density, temperature, and velocity remain constant over time. Think flight conditions need to stay the same. What is the continuity equation? A1v1 = A2v2 What is Bernoulli's Equation? Pt=Ps+(1/2)pV^2 q represents dynamic pressure What is indicated airspeed? (IAS)? Actual instrument indication of the dynamic pressure the airplane is exposed to during flight? What is calibrated airspeed (CAS)? IAS corrected for position/ instrument error What is Equivalent airspeed? (EAS)? True airspeed at sea level on a standard day that produces the same dynamic pressure as the actual flight condition. CAS corrected for compressibility effects (closer to mach speeds where compressibility is considered) What is lift always perpendicular to? Relative wind What is True Airspeed (TAS)? Actual velocity through the air. EAS corrected for density. What is the TAS equation? TAS=IAS*sqrt (po/p) What happens to your TAS as you increase altitude? Decrease in density, so higher TAS. What is ICE-TG? Mnemonic to remember the order of the airspeeds. What is Ground Speed (GS)? Actual speed over the ground. GS=TAS+- wind component (headwind subtract, tailwind add) What is the mean camber line? Line that runs through the middle of the airfoil. Halfway between upper and lower surfaces What is a chordline? straight line that passes through the leading and trailing edges that is infinitely long. What is chord? Measurement between the leading and trailing edges of an airfoil. What is the difference between a root chord and a tip chord? Root chord is at the wing centerline while a tip chord is at the wingtip. What is camber? Max distance between mean camber line and the chordline What is wingspan? Length of wing measured from wingtip to wingtip. Entire length. What is wing area? Surface area of a wing from wingtip to wingtip including the area within the fuselage What is chordwise airflow? Air flowing at right angles to the leading edge on an airfoil and accelerates over the wing. What is the only airflow that produces lift? Chordwise airflow What is spanwise airflow? Airflow parallel to the leading edge. Not accelerated over the wing, so it produces no lift. What is pitch attitude? Angle between airplane's longitudinal axis and the horizon What is flight path? Aircrafts CG movement through an air mass. It is equal in magnitude and opposit in direction to relative wind. What is relative wind? What is its direction and magnitude? Airflow the airplane experiences as it moves through the air. Equal and opposite to flight path. What is AOA? Angle of attack. Angle between the relative wind