Claude Skills by ashfordeOU

Use when you must size the propeller geometry and set its operating point at the conceptual design point: derive the propeller diameter from the blade-tip constraint and the ground clearance, select the blade count and the blade chord from the solidity and the activity factor, compute the disk loading of the selected disk, and locate the operating point with the advance ratio from the forward motion, the revolutions per second, and the propeller diameter. Produces the propeller diameter, blad...

Use when you must size the ram air turbine: computing the RAT rotor swept area from the required emergency power at a fixed emergency airspeed with the wind-power relation P = 0.5 rho V^3 A Cp at a fixed design power coefficient, deriving the rotor disk diameter and checking the round-trip available power at that condition. Produces the required swept area, the disk diameter, the available power and margin at that condition, and a fit verdict against the stowage diameter limit for the emergen...

Use when you must size the flight and ground spoiler panels of a transport aircraft: split roll authority between the primary roll channel and the roll spoilers from the roll rate and damping derivative, size flight spoiler panel area and deflection for the roll assist share, size the ground spoiler lift dumper area from the touchdown lift dump, estimate the speed brake and lift dump drag increments, compute the spoiler hinge moment for the actuator, and check the limits. Produces spoiler are...

Use when you must size the empennage with tail volume coefficients: compute the horizontal and vertical tail volume coefficients from the tail areas, the tail arms, and the wing reference area, solve for the required tail area for a target volume coefficient, and judge the result against the typical transport ranges. Covers V_h = S_h * L_h / (S_w * cbar) and V_v = S_v * L_v / (S_w * b), with the tail arm measured from the wing aerodynamic center to the tail quarter chord. Trigger: tail volume...

Use when you must size the tires for an aircraft landing gear at the conceptual level: split the static load per tire from the takeoff weight, the gear load share, and the tire count, compute the tire diameter and width with the power law fit, select the number of tires from the load capacity per tire, set the inflation pressure, and compute the footprint contact area and the rolling radius. Produces the tire dimensions, the required tire count, and the footprint that gate the landing gear co...

Use when you must size a V-tail empennage from the equivalent horizontal and vertical tail volume requirements: convert each target volume coefficient into its equivalent area, resolve the two areas onto one canted surface pair under the planform-area projection convention, split the total area equally between the two panels, derive the panel span and chord from the surface aspect ratio, size the ruddervator control area as a fraction of the total, and verify the effective volume round trip a...

Use when performing class-I or class-II vehicle weight estimation: compute moments and center of gravity from component weights and arms, check the CG against the forward and aft envelope limits, and validate empty-weight fractions against typical band ranges per aircraft category. The skill supports weight and balance calculations in the FAR-25 / CS-25 certification context. Trigger: weight estimation, weight and balance, center of gravity, cg envelope, mass, weight fraction, moment, class-i...

Use when you must size a pressurized-cabin passenger window aperture as a flat circular pane: compute the design pressure differential from the ISA pressures at the cabin and flight altitudes with the certification pressure factor applied, compute the clamped-circular-plate bending stress at the pane edge, invert the relation for the required window-pane-thickness, check the pane-margin against the material allowable, and roll up the pane weight over the window count. Produces the design diff...

Use when you must size the wing planform geometry at the design point: compute the wing area from the takeoff gross weight and the chosen wing loading, convert the aspect ratio into the span, set the taper ratio and derive the root chord, tip chord, and mean aerodynamic chord with its spanwise station, and select the sweep angle from the cruise Mach so the section normal Mach stays at or below the section critical Mach. Produces the planform dimensions that feed weight estimation, fuel tank v...

Use when you must size the aircraft by matching wing loading and thrust to weight: compute the takeoff distance constraint, climb gradient constraint, and cruise constraint curves, and find the binding constraint that sets the minimum thrust to weight at a given wing loading. Produces the wing loading constraint envelope and the required thrust to weight for the sizing matching chart that gate the conceptual sizing trade. Trigger: wing loading, thrust to weight, matching chart, sizing, takeof...

Use when you must size a pressurized fuselage skin-stringer panel at the conceptual level: compute the hoop and longitudinal membrane stresses from the cabin differential pressure and the fuselage radius, derive the skin thickness from the governing hoop stress with the 1.5 factor of safety and the minimum gauge, bound the stringer spacing from the flat panel buckling allowable, set the frame pitch from the stringer column buckling length between frames, and size the stringer area from the co...

Use when you must perform wing box sizing at the conceptual level: compute the root bending moment from the load factor, weight, and span with the elliptical lift distribution, scale the limit moment to ultimate with the 1.5 factor of safety, size the spar cap area from the bending moment and the allowable stress, and size the spar web thickness from the shear flow. Produces the root bending moment, ultimate moment, spar cap area, web thickness, and a box sized verdict that gate the wing stru...