EXACT MODELv1.0.0-draft
Flight Time, Speed & Distance Calculator
Calculate flight duration, estimated time en route (ETE), groundspeed, and distance legs for flight plans.
Key Equation:
Time = Distance / Groundspeed; Distance = Time × Groundspeed
HUB-C // TRAJECTORY & RESOURCE MANAGEMENT
Flight Planning & Performance Hub
Complete cross-country trajectory modeling from departure obstacle clearance gradients through cruise fuel consumption and continuous-descent arrival management.
Dynamic Flight Trajectory Profile
Profile Path TOD Marker
150 NM
8,500 ft
110 kt
8.5 GPH
Quick Mission Aircraft Presets:
MISSION TELEMETRY HUD
150 NM / 110 KTESTIMATED TIME (ETE)
1h 22m
81.8 total minutes
TRIP FUEL BURN
11.6 gal
70 lbs (100LL)
DAY VFR TOTAL (+30M)
15.8 gal
Night Req: 18.0 gal
TOP OF DESCENT (3:1)
23 NM out
Descent: -550 FPM
Flight Planning Rule:
14 CFR § 91.151 mandates reaching first landing point with at least 30 min (Day) or 45 min (Night) reserve at normal cruise. Top of descent initiates at 23 NM before arrival.
02 //The 4-Stage Flight Planning Solver Sequence
STAGE 1 // CLIMB
Climb Gradient
Converts required ft/NM standard instrument departure gradients into cockpit FPM vertical speeds.
Solve Climb Gradient →STAGE 2 // EN-ROUTE
Time & Distance
Solves scalar kinematic relationships (Distance = Speed × Time) across leg waypoints with fuel rates.
Solve Time & Dist →STAGE 3 // RESERVES
Fuel Burn & Reserves
Calculates trip fuel burn plus mandatory VFR (+30/45 min) and IFR (+45 min) regulatory reserves.
Solve Fuel Burn →STAGE 4 // ARRIVAL
Top of Descent (TOD)
Computes exact horizontal distance and vertical descent rate required for unstabilized approaches.
Solve TOD Profile →03 //Flight Planning Calculator Engines
STANDARDIZED REFERENCEv1.0.0-draft
Aircraft Fuel Burn, Endurance & Reserve Calculator
Calculate trip fuel burn, flight endurance, and jurisdiction-labeled reserves (14 CFR § 91.151/167) with fuel weight conversions.
Key Equation:
TripFuel = FuelFlow × Time; ReserveFuel = FuelFlow × ReserveDuration; TotalWeight = TotalVolume × Density
EXACT MODELv1.0.0-draft
Top of Descent (TOD) & Descent Rate Calculator
Calculate descent initiation distance and required vertical speed (FPM) for a target altitude and flight profile.
Key Equation:
Distance(NM) = (AltitudeToLose_ft / 6076.115) / tan(Angle); VerticalSpeed(FPM) = Groundspeed(kt) × tan(Angle) × (6076.115 / 60)
EXACT MODELv1.0.0
Climb Gradient & Obstacle Clearance Calculator
Convert between ft/NM, percentage gradient, vertical speed (FPM), and climb angle, with TERPS obstacle clearance surface analysis.
Key Equation:
VS = (Gradient × GS) / 60; Gradient = (VS × 60) / GS; % = (Gradient / 6076.1155) × 100; θ = arctan(% / 100)
04 //DPE Oral Exam Checkride Standards (Flight Planning & Fuel Law)
What are the legal fuel reserve requirements under FAA Part 91 vs EASA Part-NCO?↓
Under FAA 14 CFR § 91.151 (VFR), airplanes must carry sufficient fuel to reach the first point of intended landing plus 30 minutes of reserve fuel at normal cruising speed during the day, or 45 minutes at night. Under EASA Part-NCO.OP.125, the minimum VFR reserve is 10 minutes for local flights in the vicinity, 30 minutes for cross-country flights by day, and 45 minutes by night. IFR flights require additional reserves to reach an alternate airport plus 45 minutes (FAA § 91.167).
How is Climb Gradient (ft/NM) converted to Rate of Climb (ft/min)?↓
Rate of Climb (FPM) is proportional to groundspeed: ROC (ft/min) = Climb Gradient (ft/NM) × Groundspeed (kt) / 60. For example, to meet a standard 200 ft/NM obstacle clearance gradient at a groundspeed of 120 kt, an aircraft must maintain at least 200 × 120 / 60 = 400 FPM.
What is the 3:1 Rule of Thumb for Top of Descent (TOD)?↓
The 3:1 rule states that an aircraft on a standard 3° descent path requires 3 nautical miles of horizontal distance for every 1,000 feet of altitude to lose: TOD Distance (NM) = Altitude Loss (ft) / 1,000 × 3. Target vertical speed is approximately 5 × Groundspeed (kt).