Aerospace Systems: Fixed-Wing Aircraft Aerodynamics

Define the boundary layer as a thin surface-attached air layer mediating all aerodynamic forces. Compare laminar and turbulent regimes, laminar's low drag but higher separation risk, turbulent's stronger wall shear.

Investigate how boundary layer separation as angle of attack increases destroys the suction peak under adverse pressure gradients, leading to stall with lift loss and drag rise.

Read the airfoil lift curve: lift coefficient versus angle of attack, to understand low-speed behavior, the maximum lift coefficient, stall, cruise, climb, landing, and how flaps shift the curve upward.

Understand Reynolds number as the key to scaling aerodynamics from insects to airliners. See how inertia and viscosity shape lift, drag, and wind tunnel testing across scales.

Explore how ground effect boosts lift and reduces induced drag when a wing flies within one wingspan of the surface, reshaping takeoff and landing dynamics.

Explore how gusts and disturbed air interact with a wing, spiking lift and load factors up to 1.6g, and examine convective, mountain wave, and clear air turbulence.

Explore how wing planforms, aspect ratio, and span efficiency shape aerodynamics. See why long, slender wings dominate low-speed lift and how rectangular, tapered, elliptical, and delta layouts suit different roles.

Explore three dimensional wing design elements: sweep, dihedral, and twist, and how they affect compressibility, roll stability, stall behavior, and efficiency in transport aircraft.

Explore leading edge devices—the front half of the high lift system—slats, Kruger flaps, and slots—that delay stall and boost lift, enabling low-speed takeoffs and landings, especially with trailing edge flaps.

Explore four trailing-edge flap geometries—plane, split, slotted, and Fowler—and how each deflects to increase lift coefficient, with Fowler offering the largest gain through track mechanisms.

Discover how wingtip devices, including plain tips, blended winglets, split tip winglets, and raked wingtips, reduce induced drag and cruise fuel burn by 3–6% across modern airliners.

Explore how spoilers, speed brakes, and lift dumpers manipulate lift and drag for roll control, descent, and landing. Learn their diverse implementations across modern wings.

Explore compressibility above Mach 0.3 by defining Mach number as speed over local sound—set by air temperature—and its four regimes: subsonic, transonic, supersonic, and hypersonic with drag, shocks, and heating.

Investigate the transonic regime where parts of the flow over the wing reach sonic, shocks form and interact with the boundary layer, causing shock-induced separation and defining Mcrit and MDD.

Design supersonic wings by using thin sharp airfoils, high sweep or delta shapes, and area ruling to smooth cross-sectional area and reduce wave-drag at Mach 1 and beyond.

Explore wave drag management through five strategies—thin sharp-edged airfoils, high-sweep or delta platforms, area ruling, supercritical airfoils, and anti-shock bodies—and see how modern airliners combine them for transonic cruise.

Explore hypersonic considerations where aerothermal heating and real gas effects dominate, making thermal protection paramount and shaping blunt leading-edge strategies and high-temperature materials like carbon-carbon composites.

Understand aeroelasticity in fixed-wing aircraft by examining flutter, divergence, and control reversal, their design countermeasures, and verification through ground and flight tests, plus a transition to propulsion.

Apply blade element theory to treat a propeller as a stack of airfoil sections, summing thrust and torque with twist and angle of attack, guided by diameter, pitch, and blades.

Explore piston aero engines and constant speed propellers in small general aviation aircraft; learn the four-stroke cycle, RPM control, and independent manifold pressure for efficient cruise.

Explore the five stations of a classical turbojet—the inlet, compressor, combustor, turbine, and nozzle—and the Brayton cycle that converts fuel into thrust.

Explain the turbofan architecture, where a large front fan bypasses most air around a turbojet core and bypass ratio governs thrust, fuel burn, noise, and high vs low bypass regimes.

Examine turboprops and turboshafts sharing a turbofan-like core, driving propellers or rotors via a reduction gearbox, with turboprops around 15:1 and residual exhaust, turboshafts around 100:1 and no exhaust.

Explore fighter propulsion technologies, including afterburners, variable geometry inlets, and thrust vectoring, tuned for Mach 2 supersonic flight and post-stall maneuverability.

Explore how ailerons, elevator, and rudder control roll, pitch, and yaw across the three axes, with coordinated input and autopilots blending all three for smooth flight.

Secondary surfaces like trim tabs, servo tabs, and all-flying tails lighten pilot workload and provide high-speed authority. Trim tabs adjust for steady flight; servo tabs and stabilators generate moments.

Static stability on the three axes relies on the horizontal stabilizer, CG ahead of the aerodynamic center, dihedral, and the vertical fin, generating restoring moments and typical margins.

Identify the four natural dynamic modes of fixed-wing aircraft—fugoid, short period, dutch roll, and spiral—and how yaw dampers and autopilots mitigate them.

Explain fly-by-wire architecture with force sensor inputs, three identical primary computers and two dissimilar secondary computers, cross-checking and voting to command actuators at high cycle rates.