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Key notes

081 Principles of FlightChapter 7
ItemValue / rule
LiftL = ½ρV²SCL = qSCL
Best L/D AoA~3–4° at VMD
CL at 1.3 VS~59% CLMAX
Critical AoA~16° (design dependent)
Induced dragCDi = CL²/(π×AR); ∝ 1/V²
Parasite dragIAS²
Ground effectWithin ½ wingspan; ~80% CDi lost
Increases VSDecreases VS
Mass, load factor (√n), forward CGFlaps, slats
Icing, reduced thrust
Sweepback, high altitude (compressibility)
DeviceCritical AoACLMAXLocation
SlatsIncreasesLarge increaseOutboard
FlapsDecreasesIncreasesInboard
SpoilersDecreases CL
TermMeaning
MCRITFirst local M1 on wing (no shock below)
MCDRDrag divergence Mach
MMOMax operating Mach
VMOMax operating IAS
Coffin cornerVS = MCRIT at altitude
SpeedWhenNotes
VMCGGroundNo NWS; CG aft; ↓ with altitude/temp
VMCAAir, T/O5° bank max; ↓ with altitude/temp
VMCLLandingMax roll rate; altitude independent
CategoryLimit
Transport+2.5 / −1 g (flaps +2)
Normal+3.8 / −1.52 g
Utility+4.4 / −1.76 g
Aerobatic+6 / −3 g

PARE — Power idle, Ailerons neutral, Rudder opposite, Elevator forward.