Meteorology and Flight Planning
Weather knowledge
Candidates must interpret METARs, TAFs, GFAs, and SIGMETs, and understand the formation of cumuliform versus stratiform cloud, the causes of icing and turbulence, and the structure of frontal systems. Know that freezing rain implies a warm layer aloft above a sub-freezing surface layer, and that it is a severe icing hazard. Understand how a low-pressure system's fronts affect visibility, ceiling, and wind shift timing.
Flight planning
Flight planning questions test fuel computation, alternate requirements, and the interpretation of winds aloft. You should be able to compute true altitude from indicated altitude, temperature, and pressure altitude, and to convert between true, magnetic, and compass headings using variation and deviation.
Traps
The most common traps are unit conversions (knots versus miles per hour), applying variation with the wrong sign, and confusing true altitude with absolute altitude. Questions about icing often hinge on whether the temperature is in the clear air or in cloud range.
Rule of thumb
Use the 1-in-60 rule: a 1° heading error produces about 1 nautical mile of track error per 60 nautical miles flown. To correct a 3 NM offset after 60 NM, alter heading by about 3°. For altitude, true altitude differs from indicated by roughly 4 feet per 1,000 feet per degree Celsius of ISA deviation.