Now look at the fuel section — Page 346, Lesson 438

This is the index of the book — the alphabetical listing of every topic covered in the Airframes and Systems manual, with the page number where each subject begins. I want to walk you through what this tells you about the structure of the course, because the index itself is a study tool. Let's start with the hydraulic system entries, since they cluster together. You have Hydraulic Accumulators on page 63, Hydraulic Jacks on page 64, Hydraulic Lock on page 65, and Hydraulic Motors on page 65. These are all components of the aircraft's hydraulic power system — the accumulators store pressurized fluid, the jacks convert hydraulic pressure into linear motion, the motors convert it into rotary motion, and hydraulic lock is a condition you must understand to avoid damaging actuators. Notice the distinction between Hydrostatic Pressure on page 47 and the hydraulic components — hydrostatic pressure is the pressure exerted by a fluid at rest, which is the fundamental principle the whole hydraulic system relies on. Now look at the fuel section. You have JET A on page 312, JET A1 on page 312, and JET B on page 312. These are the three main aviation turbine fuel grades. JET A and JET A1 are kerosene-type fuels, with JET A1 having a lower freezing point for long-haul operations; JET B is a wide-cut fuel, a blend of kerosene and gasoline fractions, used in colder climates. They're all on the same page because the book treats them together as a comparison. The landing gear section gives you Inflation Valve on page 121, Inner Tubes on page 121, and Knurled Flange on page 115. The inflation valve is how you pressurize the tyre, the inner tube is the air-holding bladder inside certain tyre constructions, and the knurled flange is a serrated fitting — the knurling gives you a gripping surface — used in the wheel assembly. The structural entries are spread through the early pages. Longerons on page 15 are the main longitudinal members of the fuselage — the long, fore-and-aft structural elements that carry the bending loads. Mainplanes on page 20 is the technical term for the wings. Materials on page 25 covers the substances the airframe is built from, and Intergranular Corrosion on page 29 is a specific corrosion type that attacks along the grain boundaries of the metal — a critical maintenance concern. The mass entries are on page 30: Maximum Structural Landing Mass (MSLM) — the maximum weight at which the aircraft is certified to land — and Maximum Structural Taxi Mass, which is the maximum weight for ground manoeuvring, and it's higher than the take-off mass because you burn fuel during taxi. The flight controls section has Leading Edge Devices on page 158, Horn Balance on page 169, Mass Balance on page 172, and Mach Trim on page 180. Leading edge devices are the slats and flaps on the wing's front edge; horn balance is a control-surface balancing method; mass balance is weight distribution for flutter prevention; and Mach trim is the automatic pitch trim that compensates for Mach-number-related pitch changes at high speed. The pressurisation and air conditioning section gives you Humidifier on page 212 and Mass Flow Controller on page 212 — the humidifier adds moisture to the cabin air, and the mass flow controller regulates the quantity of air entering the cabin. Then Inwards Relief (inwards Vent) Valve on page 220 is the valve that lets outside air in if cabin pressure drops below ambient. The warning systems give you Horn Isolation Switch on page 109 — the switch that silences the take-off configuration warning horn — and Ice Detector Heads on page 241, the sensors that detect ice accretion on the airframe. Finally, Hoop Stress on page 11 is the circumferential stress in a pressurised cylinder — the stress that tries to split the fuselage skin around its circumference — and Linear Slide Selector on page 68 is a hydraulic control valve that selects flow direction by sliding a spool linearly. Now, the figure I have available is Figure 2.16, Hydraulic Accumulators, on page 69 — that's the diagram you'll see when we reach the accumulator lesson proper. That's the index. It's your map of the whole syllabus — every one of these entries is a topic we will cover in full, in the order the page numbers dictate.