This is the compact version: the formulas worth recognizing, the units that usually trip people up, and a link to the exact PilotDesk calculator when you want to check the arithmetic. It is built for study and classroom use—not as a substitute for the POH, AFM, regulations, charts, or current weather.
Knots are nautical miles per hour. Convert minutes to hours when using knots directly.
Quick check: 120 kt = 2 NM/min.Calculator →Useful for quick timing, descent, and climb-gradient work.
90 kt = 1.5 NM/min · 150 kt = 2.5 NM/min.Calculator →Use hours with gallons per hour or pounds per hour.
Actual planning may need start, taxi, climb, reserve, alternate, holding, and contingency fuel.Fuel calculator →θ is the smallest angle between runway direction and wind direction.
30° ≈ 50% crosswind · 45° ≈ 71% · 60° ≈ 87%.Calculator →A quick inHg/feet estimate. Lower pressure raises pressure altitude.
For performance work, use the altitude input and method specified by the aircraft data.Calculator →Useful lower-atmosphere mental estimate.
ISA deviation = OAT − ISA temperature.Calculator →PA and DA in feet; temperatures in °C.
The 120 ft/°C relationship is an approximation, not a precision atmosphere model.Calculator →Groundspeed matters. A stronger tailwind requires more FPM to maintain the same climb gradient.
Calculator →Groundspeed in knots gives approximate vertical speed in FPM.
The ×5 rule is intentionally a shortcut; the exact trigonometric value is slightly higher.Calculator →Applies to a coordinated, constant-altitude turn.
60° bank = 2 G.Calculator →Use the appropriate 1-G stall speed and load factor for the condition being studied.
At 2 G, theoretical stall speed is about 1.414× the 1-G value.Calculator →Use groundspeed in knots, not indicated airspeed.
100 kt → about 885 ft AGL.Calculator →The math finds the loaded CG. The approved envelope decides whether it is acceptable.
Calculator →Use the aircraft's actual LEMAC and MAC dimensions.
Calculator →Add 180° below 180°, or subtract 180° at or above it. Write a zero result as 360°.
075° ↔ 255°.Calculator →FAA Airplane Flying Handbook estimate: pressure in PSI, result in knots. At 36 PSI, 8.6 × 6 = 51.6 kt. The rounded 9× shortcut gives 54 kt.
It is not a runway-performance guarantee or substitute for aircraft guidance.Calculator →Takeoff distance, landing distance, climb performance, VMC, best glide, and aircraft limitations are aircraft-specific. A generic internet shortcut cannot replace the current POH/AFM. Maneuvering speed also deserves care: use the approved data and the aircraft's stated method rather than treating a forum mnemonic as a universal certification rule.
Memorize the relationships well enough to recognize a bad answer. If your crosswind is larger than the reported wind, 120 knots somehow becomes 10 NM per minute, or a warmer-than-standard day produces a dramatically lower density altitude with unchanged pressure, stop and check the inputs and units.
Source trail: PilotDesk's longer Pilot Math Formulas reference links each topic to its calculator and explanation. For controlling material, use current FAA handbooks and the exact aircraft POH/AFM. See Sources & Methods.
