What does the syllabus require me to know about weather?

Know what TP 15263 Section 4 asks a candidate to be able to do about the atmosphere, pressure, moisture, wind, icing and thunderstorms, and about the weather services an RPA pilot actually uses.

• You know that the examinations are built on TP 15263, so its sections are the syllabus. TP15263 area4
• You know that Section 4 mixes basic and advanced rows, so a subject marked advanced is not examined at the basic level. TP15263 area4

Section 4 is the largest area in the syllabus: fifteen categories running from the composition of the atmosphere to aviation forecasts. As everywhere, the objectives are printed once per category, and the type-of-operation column is what tells you whether a row is basic work or advanced work. TP15263 area4

The atmosphere category asks for the chemical composition of the atmosphere. TP15263 area4

The pressure category, which is advanced, asks for the three pressures to be defined — atmospheric, station and sea level — for how pressure varies with height, for the movement of air that high- and low-pressure systems, convergence and divergence produce, and for relating weather characteristics to pressure systems. TP15263 area4

Altimetry is where this becomes operational rather than descriptive: recall the factors that affect density altitude, and assess weather and density altitude for anticipated performance — take-off and launch — and against flight envelope limitations. TP15263 area4

The moisture objectives are the ones that connect two things a pilot uses together: the relationship between lapse rate, temperature-dewpoint spread and cloud base, and the effect of moisture and temperature on cloud formation and the height of cloud base, including the significance of cloud base height for potential air traffic. TP15263 area4

Stability asks for the effects of stable and unstable air masses on visibility, turbulence and smog layers. TP15263 area4

Clouds and surface layers are basic subjects with concrete objectives: identify cloud types and their impact on flying operations, discuss observed vertical cloud development, explain how fog forms, identify what dissipates it, and identify the different obstructions to vision. TP15263 area4

Turbulence asks for the sources of mechanical turbulence, its formation around large objects and mountain tops, and the sources of micro-climate turbulence and wind shear. TP15263 area4

Wind is the longest objective list in the section: the effect of pressure gradient on horizontal air movement, how wind changes in the friction layer as the surface heats, the definition of wind shear and its effect on turbulence, the formation of land and sea breezes, and anabatic and katabatic effects explained from a picture. TP15263 area4

Fronts, which are advanced, ask for the relationship between air masses and the creation of fronts, and for the changes in weather as a front approaches and passes. TP15263 area4

Icing is a basic subject here and a serious one for an RPA: how icing forms and the conditions that cause it, the weather conditions that cause surface contamination, and the components of an RPA that are susceptible to icing. TP15263 area4

Thunderstorms are advanced, and the objectives are the three that a forecast is read for: the three stages of development, the surface weather characteristics of an approaching thunderstorm, and the hazards likely to occur with thunderstorm activity. TP15263 area4

The services category is about where the information comes from: identify the sources for local weather information, and describe the differences in cloud base and wind forecasts between aviation and non-aviation sources — a difference that matters because an RPA operation is planned against a specific site. TP15263 area4

Reports and forecasts, both advanced, are about use rather than recollection: compare reported weather with the regulatory requirements, demonstrate awareness of coded weather information and identify methods of decoding, and for forecasts assess ceiling, wind, turbulence, precipitation and visibility against operational objectives and against control station requirements such as lightning. TP15263 area4

That last phrase is the one to notice: the syllabus expects the control station and the crew to be assessed as part of the weather decision, not only the aircraft. TP15263 area4

You are ready for Section 4 questions when you can:

• State the composition of the atmosphere TP15263 area4
• Define atmospheric, station and sea level pressure, and relate weather to pressure systems TP15263 area4
• Recall what affects density altitude, and assess it against performance and envelope limits TP15263 area4
• Relate lapse rate and dewpoint spread to cloud base TP15263 area4
• Identify cloud types, vertical development, fog formation and obstructions to vision TP15263 area4
• Name the sources of mechanical, micro-climate and orographic turbulence, and of wind shear TP15263 area4
• Explain how icing forms, and which RPA components are susceptible TP15263 area4
• Describe the three thunderstorm stages and their hazards TP15263 area4
• Compare reported and forecast weather with the regulatory and operational requirements TP15263 area4

Symptom	Likely cause	What to do
An advanced-only subject appears in a basic question	The type-of-operation column differs per category	Check the column before assuming TP15263 area4
A topic has no objective beside it	Objectives are printed once per category	Read the category's list TP15263 area4
The control station is left out of a weather decision	Forecasts are assessed against control station requirements too	Include the crew and the station TP15263 area4
A non-aviation forecast is used for cloud base	The services objective names that difference explicitly	Use aviation sources for aviation decisions TP15263 area4

Practise: Composition and physical properties Practise: Pressure measurements Practise: Pressure altitude Practise: Temperature variations with altitude Practise: Types applicable to low level flying and recognition Practise: Fog formation Practise: Formation  Practise: Requirements for development  Practise: Automated Weather Observation Station (AWOS), Basic Weather Information System (LWIS) Aviation Routine Weather Report (METAR),

• TP 15263E, Section 4 — Meteorology (the sample learning objectives table)

The corpus holds the requirements and not the meteorological teaching material behind them — it says a candidate must be able to explain how fog forms, and does not contain the chapter that explains it. Where the corpus does carry the material, the lesson that teaches it is the better next read: the lapse rate worked through numerically is in the weather-minima lesson, the minimum conditions a flight may be flown in are there too, and the icing facts that apply to an RPA are in the FPV-and-icing lesson.