So once you learn how to read one, you can read them all — Page 78, Lesson 81

I want to walk you through the Simplified Flight Planning charts and how they work for a typical long-range navigation scenario. These charts are designed to give you trip fuel and time from brake release all the way to touchdown, covering the entire flight from engine start to landing. Let's start with the range categories. For distances from 0 to 1000 NM, the chart assumes one stepped climb — that means you climb in stages rather than going straight to your final cruise altitude. For distances from 1000 to 4000 NM, you use alternate planning with LRC — that's Long Range Cruise — for the first 0 to 500 NM segment, plus holding fuel planning. Now, the LRC — Long Range Cruise — graphs, along with the 0.74 Mach, 0.78 Mach, and 300 KIAS (Knots Indicated Airspeed) cruise graphs, all have the same basic presentation. So once you learn how to read one, you can read them all. These Simplified Flight Planning charts determine trip fuel and time from brake release to touchdown. That's the whole flight profile — start of takeoff roll to wheels on the ground. But here's the key: the chart gives you only the basic trip fuel. You must add several other components to get the total fuel required. Those additions include: - APU usage — the Auxiliary Power Unit running on the ground and in flight - Taxi fuel — moving on the ground before takeoff and after landing - In-flight flaps down manoeuvring — other than a straight-in approach, so if you have to go around or do a non-standard approach pattern - Cost Index Adjustments — which account for different economic speeds - Reserve fuel — the mandatory fuel you must carry for contingencies For holding fuel, you get that separately from the Holding Fuel Planning table, which is found in CAP 697 Figure 4.4. Now let's walk through the method using Example 5. Here's the scenario: - LRC trip distance: 1000 NM - Cruise at FL290 — that's Flight Level 290, or 29,000 feet pressure altitude - 50 kt headwind — wind blowing against you - ISA -10°C — that's 10 degrees Celsius colder than the International Standard Atmosphere - Estimated landing weight: 40,000 kg We need to calculate the fuel required and the flight time. Here's the step-by-step procedure: Step 1: Enter the chart at the trip distance — 1000 NM — and go vertically upward until you hit the reference line. Step 2: Follow the flow lines — those are the curved guide lines on the chart — and correct for the 50 kt headwind. The headwind flow lines will shift your position. Step 3: From that corrected point, move vertically upward to the first intersection of the Pressure Altitude lines. You're looking for the 29 intersection — that's FL290. Step 4: From that intersection, move horizontally across to the Landing Weight reference line. Step 5: Follow the flow lines to correct for the Landing Weight of 40,000 kg. Step 6: Move horizontally across and extract the Fuel Required in kilograms. Now for the trip time: Step 7: Go back to the original vertical line you started with — the one from the trip distance. Step 8: At the 29 intersection on the upper Pressure Altitude intersections — note there are upper and lower sets — move horizontally to the Trip Time reference line. Step 9: Follow the flow lines to correct for ISA -10°C. Step 10: Move horizontally and read off the Trip Time in hours and minutes. There's an important note here: if the given wind component exceeds what's shown on the chart, you can't use the headwind or tailwind flow lines directly. Instead, you must convert the trip distance from Nautical Ground Miles (NGM) to Nautical Air Miles (NAM) using this formula: NAM = NGM × Average TAS / (TAS +/- Wind Component) Where TAS is True Airspeed. So you multiply the ground distance by the ratio of your true airspeed to your true airspeed adjusted for the wind. Then you ignore the head and tail flow lines and enter the chart using NAM instead of NGM. The answers for this example are on page 80 of the book. So in summary: these charts give you a quick, graphical way to determine fuel and time for a whole flight segment, but you must always remember to add APU, taxi, flaps-down manoeuvring, cost index adjustments, and reserve fuel separately. And if the wind is stronger than the chart's flow lines can handle, you fall back on the NAM conversion formula.