Key notes
Structures
Section titled “Structures”| Topic | Key fact |
|---|---|
| DUL | 1.5 × DLL |
| Fail-safe | Redundant load paths |
| Safe life | Replace at set hours/cycles |
| Semi-monocoque | Skin + frames + stringers |
| In flight wing | Upper compression, lower tension |
| On ground wing | Upper tension, lower compression |
| Pressurisation fuselage | Tension / hoop stress |
| Flutter prevention | Mass balance, torsional stiffness |
| MZFM | Max mass without usable fuel |
Hydraulics & gear
Section titled “Hydraulics & gear”| Topic | Key fact |
|---|---|
| System pressure | 3000 psi typical |
| Skydrol | Phosphate ester — purple |
| Internal leak | Temperature rise |
| External leak | Reservoir level fall |
| Accumulator pre-charge | ~⅓ system pressure, nitrogen |
| Green / amber gear lights | Down locked / travelling |
| Aquaplaning (psi) | 9 × √(P) kt |
| Anti-skid | Releases slower wheels |
| Shimmy | Nose wheel oscillation — damper |
Piston engines
Section titled “Piston engines”| Topic | Key fact |
|---|---|
| Camshaft speed | ½ crankshaft |
| Thermal efficiency | ~30% |
| Stoichiometric ratio | 14.7:1 |
| Best power | ~12:1 |
| Carb icing range | −5°C to +18°C, RH above 60% |
| Detonation action | Reduce MAP, enrich mixture |
| Mag OFF run-on | Carbon deposits |
| Wet vs dry sump | Internal vs external oil tank |
| MRT / TRM | RPM before MAP / MAP before RPM |
| Waste gate seized | MAP high on descent, low on climb |
Gas turbines
Section titled “Gas turbines”| Topic | Key fact |
|---|---|
| EPR | Pt8 ÷ Pt2 |
| Bypass ratio | Bypass flow ÷ core flow |
| Compressor stall | Low RPM, high AoA on blades |
| Surge | Full compressor stall |
| Can combustor | 2 igniters |
| Annular combustor | Better HP turbine thermal loading |
| Creep | Blade elongation — heat + stress |
| Wet start | Fuel flow, no EGT rise |
| Hung start | Low RPM, high EGT — shut down |
| Bleed air off | ↓EPR, ↑EGT, ↑fuel flow |
| Flat rating | Constant TO thrust to OAT limit |
| Topic | Key fact |
|---|---|
| 100LL | Blue |
| Jet A-1 freeze | −47°C |
| Tank vent space | ~2% |
| Crossfeed | Any engine from any tank |
| Dumping | MTOW above MLW |
| Refuel bonding | Before cap removed |
| Vapour lock prevention | Pressure + booster pumps |
Electrics
Section titled “Electrics”| Topic | Key fact |
|---|---|
| AC frequency | 400 Hz |
| Star line V | √3 × phase V |
| Delta line I | √3 × phase I |
| NiCad hazard | Thermal runaway |
| CSD reset | Ground only |
| Paralleling | Equal V, f, phase |
| Trip-free CB | Cannot hold during fault |
| CIVIL | C leads I; I leads V in inductor |
Pressurisation, ice, oxygen, fire
Section titled “Pressurisation, ice, oxygen, fire”| Topic | Key fact |
|---|---|
| Differential | 7–9 psi typical |
| Cabin alt warning | 10 000 ft |
| Pax O₂ auto | 14 000 ft cabin |
| Bootstrap order | HX → compressor → HX → turbine |
| Icing (ground) | OAT below 10°C + moisture |
| Bleed wing anti-ice | Reduces thrust, not wing aero |
| Halon | Chemical fire break — not cooling |
| Fire handle | Fuel LP close, bleed close, gen trip |
| Chemical O₂ duration | 15 minutes |
| Cockpit O₂ smoke | 100% setting |