Introduction to PerformanceWhy Study Performance?The Anatomy of the AirplaneAirplane ConfigurationsAirplane ConfigurationsAirplane ConfigurationsThe Standard AtmosphereThe Standard AtmosphereEffect of Water Vapor on AtmosphereInternational Standard AtmosphereRegions of the AtmosphereTemperature Variation with AltitudePressure/Density Variation with AltitudePressure/Density Variation with AltitudePressure/Density Variation with AltitudeViscosityAltimetersAltimetersAltimetersErrors in AltimetersTypes of AltitudeTypes of AltitudeWeather and the AltimeterWeather and the AltimeterPitot-Static TubeThe Airspeed IndicatorThe Airspeed IndicatorThe Airspeed IndicatorAirspeed Indicator LimitationsTypes of AirspeedsVertical Speed IndicatorThe Pitot Static InstrumentsThe Magnetic CompassGyroscopic InstrumentsThe Attitude IndicatorThe Attitude IndicatorThe Turn CoordinatorThe Turn CoordinatorThe Heading IndicatorStandard Instrument Panel LayoutSources for Lecture 1AE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyIntroduction to PerformanceFlight Mechanics is the study of the motions of bodies (aircraft and rockets),through a fluid.Stability and Control Aerodynamic Performancethe science of designing for steadyand controllable fight characteristicsspeedrate of climbrangefuel consumptionmaneuverabilityrunway length requirementsAE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyWhy Study Performance?AE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyThe Anatomy of the AirplaneAE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyAirplane ConfigurationsSource: Shevell, Fundamentals of FlightAnhedralAE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyAirplane ConfigurationsSource: Shevell, Fundamentals of FlightAE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyAirplane ConfigurationsSource: Shevell, Fundamentals of FlightAE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyThe Standard AtmosphereWhy do we need to know about the atmosphere?The performance of aircraft, spacecraft, and engines depend on the atmosphere inwhich they operate, primarily density and viscosity. Density and viscosity, inturn, are functions of altitude.Density, ρ, varies with pressure, p, and temperature, TViscosity, µ, varies only with temperature, TThe “standard atmosphere” is defined from the equation of state of a perfect gas: p = ρ RTPerfect Gas LawAE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyThe Standard AtmosphereRemember: R = F + 459.7K = C + 273.15For our purposes, the atmosphere can be regarded as a homogenous gasof uniform composition that satisfies the perfect gas law.p = pressure in lb/ft2 or N/m2ρ = density in slugs/ft3 or kg/m3T = absolute temperature in Rankine (R) or Kelvin (K)R = gas constant = 1718 ft-lb/slugR or 287.05 n-m/kgKAE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyEffect of Water Vapor on AtmosphereWhen there is a significant amount of water vapor in the air, the density ischanged, but by a very small amount.ρ = 0.002243 slug/ft3 dry airρ = 0.002203 slug/ft3 100% humidityAlthough the effect of water vapor on air density is very small, water vapordoes have a significant effect on engine performance and supersonicaerodynamics.AE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyInternational Standard AtmosphereTo allow for comparison of the performance of airplanes, as well as calibrationof altimeters, “standard” properties of the atmosphere have been established bythe International Civil Aviation Organization (ICAO).The ICAO and the U.S. Standard Atmosphere are identical below 65,617 feet.This standard atmosphere is representative of mid latitudes of the northernhemisphere.“Standard” sea level properties are:g0 = 32.17 ft/s2 = 9.806 m/s2P0 = 29.92 in Hg = 2116.2 lb/ft2 = 1.013 x 105 N/m2T0 = 59 F = 518.7 R = 15 C = 288.2 Kr0 = 0.002377 slug/ft3 = 1.225 Kg/m3AE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyRegions of the AtmosphereExosphere-rarefiedIonospherePositive Temperature GradientStratosphereZero Temperature GradientTroposphereNegative Temperature GradientTropopause ( 36,089 ft)300 ~ 600 mi50 ~ 70 mi5 ~ 10 miIn subsonic airplane aerodynamics, only the troposphere and stratosphereare important.AE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyTemperature Variation with AltitudeBelow 36,089 ft, we assume there is a constant drop of temperature from sealevel to altitudeT = T1 + a ( h - h1)a = “lapse rate” = -0.00356616 F/ft in the standard atmosphereT1 and h1 are reference temperatures. For sea level, T1 = T0 and h1 = 0Above 36,089 ft in the stratosphere, the standard temperature is assumedconstant and equal to -69.7 F.AE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyPressure/Density Variation with AltitudeBelow 36,089 ft(relative to standard sea level values)TT0= Θ = 1 + h = 1 - 6.875 x 10-6 h aT0pp0= δ = Θ 5.2561ρρ0= σ = Θ 4.2561AE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyPressure/Density Variation with Altitudepp0ρρ0= 0.2234 exph-36,08920806.7= 0.2971 expAbove 36,089 ft(relative to standard sea level values)h-36,08920806.7T = constant = -69.7 FAE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyPressure/Density Variation with AltitudeSo, now you can calculate the temperature, pressure, and density at any point inthe troposphere or stratosphere…OR…You can use the nifty tables in the back of Anderson’s book (Appendices A, B)Be careful which units you are using...AE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyViscosityViscosity varies primarily with temperatureThere is a strong relationship between air viscosity and boundarylayer behavior. This will be discussed more when we reviewaerodynamics.Kinematic Viscosityν = µ/ρR = VlνReynold’s NumberAE 3310 PerformanceLecture 1- May 14, 2002Dr. Danielle SobanGeorgia Institute of TechnologyAltimetersProperties of the standard atmosphere can