Let me start with the performance side — Page 537, Lesson 655

This is the index of the book — the alphabetical listing of topics with their page numbers. I want to walk you through what this index tells us about the structure of the whole Mass and Balance and Performance syllabus, because it's a map of everything we're going to cover. Let me start with the performance side. You'll see Performance Class A, B, and C all listed at page 17. These are the three certification categories for aeroplanes. Performance Class A is for multi-engine aeroplanes — the kind that can continue flying after an engine failure. Performance Class B is for single-engine aeroplanes, and Performance Class C is for multi-engine aeroplanes that cannot maintain height after an engine failure. That's a fundamental distinction you'll need throughout. Now look at the take-off and landing items. Rejected Take-off, abbreviated RTO, appears at pages 8 and 22. That's the manoeuvre where you abort the take-off and stop the aeroplane on the runway. Rotation Speed is listed at page 8 — that's the speed at which you rotate the aeroplane to lift the nose wheel off the runway. Reference Landing Speed is at pages 8, 207, and 240 — that's the speed used as the reference for landing performance calculations. On the drag side, we have Parasite Drag at page 153 and the Parasite Drag Curve at page 51. Parasite drag is the drag that doesn't result from the production of lift — it's the drag from the aeroplane's shape, skin friction, and interference. And there's Reverse Command at page 57 — that's the region of flight where, on the back side of the power curve, you need more power to fly slower. Let me look at the climb and descent items. Rate of Climb is at page 71, Rate of Descent at page 97. These are the vertical speeds — the climb or descent performance of the aeroplane. Now the range and endurance items. Range is at page 124, Propeller Aeroplane Range at page 125, and Propeller Aeroplane Endurance at page 120. Range is how far the aeroplane can fly, endurance is how long it can stay airborne. And Payload vs Range at page 129 — that's the trade-off between how much payload you carry and how far you can fly. On the altitude side, we have Optimum Altitude at page 134 — that's the altitude at which you get the best performance, usually the best fuel economy. Pressure Altitude is at page 8 — that's the altitude read when the altimeter is set to the standard pressure setting of 1013.25 hectopascals. And Outside Air Temperature at page 8 — that's the actual temperature of the air outside the aeroplane. Now the abbreviations. PA at page 13 — that's Pressure Altitude again, the same as Pressure Altitude at page 8. PCN at pages 13 and 274 — that's Pavement Classification Number, the number that tells you the load-bearing capacity of a runway pavement. PMC at page 13 — that's a performance-related abbreviation, and RTO at page 14 is the Rejected Take-off abbreviation again. On the flight control side, we have Pitch at page 8 and Pitch Setting at page 8 — pitch is the nose-up or nose-down attitude of the aeroplane, and pitch setting is the angle of the propeller blades. Roll at page 8 — that's the rotation about the longitudinal axis, banking the wings. And finally, Runway at page 8, and the entry that's cut off at the end, Runway S — that's likely Runway Slope or Runway Surface, but the index cuts off there. So this index is your roadmap. Every one of these topics — the performance classes, the speeds, the drag types, the altitude definitions, the abbreviations — is a chapter we're going to work through. When you see an abbreviation like PA or PCN or RTO, you now know what it stands for and roughly where in the book it lives. That's the value of an index: it lets you navigate the whole syllabus.