Flight Manual. . . . . . . . . . . . . . . . . . . . . . . . 25 — Page 125, Lesson 141

This is the index of the Mass and Balance section of your manual — the map of everything we're about to cover. Let me walk you through what these entries actually mean, because each one is a tool you'll use on the line. Start with Flight Manual at page 25. That's the authoritative document for your aircraft — the manufacturer's approved data. When we talk about Limitations on the same page, those are the hard operating boundaries: maximum weights, CG limits, never-exceed speeds. These aren't suggestions; they're certified limits you must respect. Longitudinal Stability on page 28 — that's the aircraft's tendency to return to its trimmed attitude after a disturbance. It's directly tied to where your centre of gravity sits. Glide Angle on the same page — the descent path angle with power off. Both of these are CG-dependent, which is why they appear together. Longitudinal Axis (Centre Line) on page 29 — that's the nose-to-tail reference line. All your CG measurements are made along this axis, usually in inches or millimetres aft of a datum point. Loading Index on page 30 — this is a shorthand number airlines use instead of raw weights and arms. It simplifies the arithmetic on a load sheet. You'll see it everywhere in transport operations. List of Basic Equipment on page 34 — the standard installed items the empty weight includes: seats, avionics, unusable fuel, oils. Food and Duty Free Trolleys on the same page — these are variable loads in the cabin, and they have their own weight and CG positions on the manifest. Hydrostatic Units on page 35 — these are the fuel quantity sensors in the tanks. They measure fuel by pressure, and they matter because fuel weight is a major variable in your mass calculations. Now the units — Gallons, Kilograms, Litres all on page 36. Gallons and litres are volume; kilograms are mass. You'll convert between them using fuel density, and getting that conversion right is critical — a fuel load error is a mass error. Loaded Mass and CG Position for Light Aircraft on page 41 — that's the method for single-engine piston types, where you compute the loaded weight and its CG from a simple calculation or graph. Landing CG on page 43 — the centre of gravity at the moment of touchdown. It differs from takeoff CG because you've burned fuel en route, and it must be within the landing envelope. Linear / Running Loads on page 58 — these are distributed loads, like cargo spread over a floor section, expressed in weight per unit length. Load Spreaders on the same page — the beams or plates that distribute a concentrated load across multiple floor structure members. Floor Loading on page 57 — the maximum weight per unit area the floor can support. That's why you use load spreaders. Light Twin Piston / Propeller Aircraft (MEP1) on page 60 — that's the multi-engine piston class, and it has its own mass and balance procedures distinct from singles. Fuel Load Definitions on page 65 — the standard fuel terms: taxi fuel, trip fuel, reserve, contingency. Each has a specific meaning in your fuel planning. Loading Manifest - MRJT1 on page 68 — the actual load sheet for the medium-range jet transport. Load and Trim Sheet (MRJT1) on page 71 — the combined document showing both the load distribution and the resulting CG. Limitations for JAR - Medium Range Twin Jet on page 73 — the certified limits for that specific aircraft type under JAR regulations. Last minute change on page 13 — that's the procedure when a passenger or bag is added or removed just before departure. You must re-verify the CG is still within limits. So this index is your roadmap. Each page is a tool: some are calculations, some are documents, some are limits. We'll take them one at a time, starting with the Flight Manual and Limitations.