500 · 1,000 · 2,000 (1 SM, clear of clouds in pattern within ½ SM of runway)
> 1,200 AGL, < 10,000 MSL — day
1 SM
500 · 1,000 · 2,000
> 1,200 AGL, < 10,000 MSL — night
3 SM
500 · 1,000 · 2,000
> 1,200 AGL and ≥ 10,000 MSL
5 SM
1,000 · 1,000 · 1 SM
B/C/D/E surface area: no VFR under a ceiling < 1,000 ft, and ground visibility ≥ 3 SM to take off, land or enter the pattern (91.155(c),(d)) — otherwise Special VFR (91.157): clear of clouds, 1 SM; at night only with instrument rating + IFR airplane.
Airspace entry & equipment
Entry
Equipment
A
IFR clearance
IFR, Mode C, ADS-B
B
“Cleared into Class B”
2-way radio, Mode C, ADS-B (30 NM veil)
C
2-way comms (ATC uses your call sign)
2-way radio, Mode C, ADS-B (and above)
D
2-way comms
2-way radio
E/G
None (VFR)
ADS-B/Mode C ≥ 10,000 MSL (not ≤ 2,500 AGL)
Speeds (91.117): 250 KIAS < 10,000 MSL · 200 KIAS ≤ 2,500 AGL within 4 NM of Class C/D primary · 200 KIAS under a Class B shelf / VFR corridor.
Day — ATOMATOFLAMES: Airspeed ind · Tachometer · Oil pressure · Manifold pressure (altitude engine) · Altimeter · Temp gauge (liquid-cooled) · Oil temp · Fuel gauge · Landing gear position (retractable) · Anticollision lights (certificated after Mar 11, 1996) · Magnetic compass · ELT · Safety belts / shoulder harnesses.
Night — add FLAPS: Fuses (spare set) · Landing light (if for hire) · Anticollision lights · Position lights · Source of electrical power.
Cross-country planning — order of calculations PHAK Ch 16
Route. Draw the course, pick checkpoints, measure each leg's true course (TC) at a meridian near the middle of the leg, and its distance in NM.
Magnetic course → altitude. MC = TC − east / + west variation. Above 3,000 ft AGL fly odd thousands + 500 for MC 0–179°, even + 500 for 180–359°; clear terrain (MEF), obstacles and airspace. 91.159
Winds aloft for that altitude and time: FB direction is true, speed in knots, temperature °C; interpolate between levels. AWH 27.2
Performance from the POH with pressure altitude and temperature: climb time, fuel and distance; cruise RPM, TAS and fuel flow. PHAK Ch 11
Wind triangle for each leg (E6B or the formulas): WCA and groundspeed. Keep it all in true: TC, FB winds, TAS.
Headings: TH = TC ± WCA (+ for wind from the right) → MH = TH − east / + west variation → CH = MH ± deviation (compass card).
Time per leg = distance ÷ GS × 60 min. The first leg includes the climb.
Fuel per leg = time × GPH; add start, taxi and run-up, and the climb. Total it.
Reserve: total + 30 min (day) or 45 min (night) at cruise must fit within usable fuel. 91.151
Weight & balance at takeoff and at landing (fuel burned × 6 lb/gal).
Takeoff and landing distances at each airport for its density altitude, wind and runway. 91.103
Brief, file, fly: weather, NOTAMs, TFRs; file and activate the flight plan. In the air, start a timer, note checkpoint times, actual GS = distance ÷ time, then revise ETAs and fuel.
Pressure altitude
PA = elevation + (29.92 − altimeter) × 1,000 ft
Standard temperature
ISA = 15 °C − 2 °C per 1,000 ft of PA
Density altitude
DA ≈ PA + 120 × (OAT − ISA)
True airspeed
TAS ≈ CAS + 2% per 1,000 ft (rule of thumb)
Wind components
crosswind = W × sin θ, headwind = W × cos θ θ = angle between wind and course; sin 30° = ½, 45° ≈ 0.7, 60° ≈ 0.9
Wind correction
WCA ≈ crosswind × 60 ÷ TAS (degrees, into the wind)
Groundspeed
GS ≈ TAS − headwind (or + tailwind)
Headings
TH = TC ± WCA · MH = TH − E / + W var · CH = MH ± dev
Time
min = NM ÷ GS × 60
Fuel
gal = min ÷ 60 × GPH · 100LL ≈ 6 lb/gal
Off course (rule of 60)
to parallel: NM off ÷ NM flown × 60° · to regain: add NM off ÷ NM to go × 60°
Start descent
altitude to lose ÷ fpm × GS ÷ 60 = NM before
Example: TC 040°, 55 NM, wind 010° at 20 kt, TAS 110 kt, variation 15° E, compass card +2°, 8.5 GPH. The wind is 30° off the nose from the left: crosswind 20 × ½ = 10 kt, headwind 20 × 0.87 ≈ 17 kt. WCA ≈ 10 × 60 ÷ 110 ≈ 5° left → TH 035° → MH 020° → CH 022°. GS ≈ 110 − 17 = 93 kt → 55 ÷ 93 × 60 ≈ 36 min → 36 ÷ 60 × 8.5 ≈ 5.1 gal.
FB winds aloft (DDff+TT, true, kt, °C): no wind within 1,500 ft and no temp within 2,500 ft of station elevation; 9900 = light & variable; direction + 50 means add 100 kt (7545 = 250° at 145 kt); no minus sign above 24,000 ft. AWH 27.2
G-AIRMET: Sierra IFR/mtn obsc · Tango turb/wind/LLWS · Zulu icing/FZLVL.
Cloud base ≈ (T − Td °C) ÷ 2.5 × 1,000 ft AGL.
Standard: 29.92 inHg = 1013.2 mb. Isobars (pressure) every 4 mb; isogonic lines = magnetic variation.
G-AIRMET 6 h · SIGMET ≤ 4 h · Convective SIGMET H+55, 2 h (AIM: 1 h), hail ≥ ¾ in · CWA ≤ 2 h.
DA ≈ PA + 120 × (OAT − ISA); PA = elev + (29.92 − alt) × 1,000.