- TAS = IAS + 3% per 2000 ft + 1% per (OAT - ISA) / 5
Note: can approximate with 1% per 600 feet - KTAS ≈ M[600+1.22(T+35)], (T in centigrade)
- True Altitude = Pressure Altitude * TISA / Tactual (hypsometric formula)
- True Altitude = Indicated Altitude + (ISA Deviation × 4/1000 × (Indicated Altitude - Elevation))
- True Altitude = (Indicated Altitude - Elevation) * Tactual / TISA + Elevation
- Density Altitude = Pressure Altitude + 120 * ISA Deviation
- Approach Rate of Descent (FPM) ≈ GS (knots) * 5
- 3:1 Rule - 3 NM for each 1000 ft of descent
- Altitude Drop / FPM = minutes
- Minutes * 2 ≈ miles
- Maximum crosswind ≈ 20% of a stall speed
- Angle of Bank for rate one turn = TAS / 10 + 7 kt
- Time to VOR: (60 * minutes between bearing) / degrees of bearing change
- Distance to VOR: (TAS * minutes between bearing change) / degrees of bearing change
← Back to blog