What is wake turbulence?

Every aircraft generates a pair of counter-rotating vortices from its wingtips as it produces lift. These vortices trail behind and slightly below the aircraft and sink at roughly 300-500 ft per minute, levelling off around 500-900 ft below the generating aircraft's flight path. The heavier and slower the aircraft, the stronger the vortices - so a large jet in the landing configuration (gear and flap down) produces the worst hazard.

Why it matters to you

A light aircraft caught in the wake of a much heavier one can experience a violent, uncommanded roll that may exceed the aircraft's roll control authority - especially dangerous close to the ground on approach or departure where there is little height to recover.

CAA wake turbulence categories

UK CAA (aligned with ICAO) groups aircraft by maximum certificated take-off mass:

• LIGHT: 7,000 kg or less
• MEDIUM: over 7,000 kg up to 136,000 kg
• HEAVY: over 136,000 kg
• There is also a SUPER (A380) category with its own larger separations.

Separation - the key numbers

At controlled aerodromes ATC applies mandatory radar and procedural spacing behind heavier aircraft. As a PPL pilot flying light aircraft you will typically be the one needing protection, so know the minimums:

• Light behind Heavy (same runway or crossing/opposite): typically 3 minutes on departure if not airborne before the heavy's rotation point, or increased radar separation on approach.
• Light behind Medium: typically 2 minutes.
• Distance-based radar separation for light aircraft behind heavy can be as much as 6 nm on final approach.
• ATC will pass a wake turbulence caution whenever relevant; the pilot remains responsible for accepting or requesting extra spacing.

Practical avoidance technique

• On approach: stay at or above the heavier aircraft's approach path and land beyond its touchdown point.
• On departure: rotate before the heavier aircraft's rotation point and climb above its flight path.
• Crossing behind: cross above the other aircraft's path, never below.
• In light/no wind, vortices can drift very slowly or stay near the runway centreline for several minutes - crosswind can drift them onto or off the runway.
• Vortices decay faster in strong wind and turbulence, slower in calm, stable air.

Common mistakes

• Assuming ATC spacing alone guarantees safety - you can still request extra time or a different departure point.
• Forgetting that wake sinks - flying below and behind a heavy aircraft's path is the worst place to be.
• Ignoring wake risk from your own light twin or larger touring aircraft when a smaller aircraft follows you.
• Believing wake turbulence only matters behind airliners - any aircraft heavier and slower than you can be a hazard.

What windshear actually is

Windshear is a sudden change in wind speed and/or direction over a short distance. It matters most close to the ground because there is little height or time to recover.

A microburst is the most dangerous form: a small, intense downdraft that hits the ground and spreads out. You fly into a headwind gain (extra lift, nose pitches up), then through the core sink, then out into a tailwind loss (lift drops, nose pitches down) - all in seconds.

Where it comes from

• Convective activity - thunderstorms and cumulonimbus, including outflow gust fronts well ahead of the storm itself.
• Frontal surfaces - especially fast-moving cold fronts.
• Temperature inversions - low-level jets sitting above a calm surface layer, common on clear still nights.
• Terrain and obstacles - hills, ridges, hangars, trees and rows of buildings near the runway causing mechanical turbulence and rotor.

Recognising it

• ATIS or tower reports of windshear, or a big difference between surface wind and forecast/gradient wind.
• Virga (rain that evaporates before reaching the ground) under cumulonimbus - a strong microburst indicator.
• Dust rings, blowing debris or a squall line visible on the ground.
• Airspeed fluctuating for no control input reason, or an unstabilised approach that will not settle down.

Handling it

• If windshear is reported or suspected on approach, go around early - do not try to salvage a bad approach close to the ground.
• Fly the recommended approach speed plus a gust/gradient allowance, commonly Vref plus half the reported gust value, up to a sensible maximum addition per the aircraft flight manual.
• Keep the approach stabilised: correct configuration, speed and rate of descent by around 500 feet AGL (or the type-specific gate) - if not stable, go around.
• If shear is encountered, prioritise pitch and power to protect airspeed and flight path, and be ready for full power and a shallower climb attitude to escape a downdraft.
• After takeoff, if shear is reported, consider delaying, using a longer runway, or increasing the rotate/climb speed margin.

Common mistakes

• Treating windshear only as a big-airport, big-jet problem - light aircraft are more vulnerable per knot of shear because their normal speeds and margins are smaller.
• Chasing airspeed with pitch alone in a downdraft instead of adding power promptly.
• Continuing an approach through reported shear hoping it clears by the time you land.
• Ignoring virga and anvil clouds because there is no rain falling on the airfield itself.
• Forgetting that gust fronts can arrive 10-15 nautical miles ahead of a thunderstorm cell, well before the storm looks close.

Why this matters

Fire and smoke in a light aircraft can go from nuisance to catastrophic in seconds. The examiner wants you to know the immediate drills cold, without hesitation, because there is no time to look things up in flight.

Engine fire on the ground (during start)

• If the engine fires on start, keep cranking the starter - this often pulls the fire back into the engine and burns it out.
• Close the throttle and mixture to cut off fuel, and get the fuel and ignition OFF.
• Cabin heat and vents should be closed to stop fumes entering the cabin.
• Evacuate if the fire does not clear immediately, taking a fire extinguisher if fitted.

Engine fire in flight

• Fuel off, mixture idle cut-off, ignition off, cabin heat and air off - this starves the fire of fuel and stops smoke entering the cabin.
• Master switch off once electrics are no longer needed, unless you need it for a mayday call.
• Establish best glide speed and select a forced landing field - a fire in flight is a land-immediately situation, not a divert-to-nearest-airfield situation.
• Sideslip away from the fire side if it helps keep flames/smoke clear of the cabin.

Electrical fire / smoke in flight

• Master switch OFF first - this isolates the whole electrical system and is the single most important early action.
• Cabin heat and vents OFF (many heating systems draw air over the exhaust, which can bring in fumes).
• Fire extinguisher on any visible flame, being careful not to damage instruments more than necessary.
• Once smoke clears, electrical items can sometimes be brought back one at a time to identify the faulty item - only do this if safe and necessary.

Cabin/cockpit fire (non-electrical)

• Identify the source, use the extinguisher, and ventilate the cabin once the fire is out to clear smoke - but don't open windows/vents while fire is active as this feeds oxygen to it.

Smoke and fume evacuation drill

• Fresh air vents open, a window cracked if safe, and a normal or precautionary landing planned promptly - smoke inhalation impairs judgement fast.

Common mistakes

• Forgetting that a continued starter crank can extinguish a start fire - candidates often jump straight to shutdown.
• Confusing the electrical fire drill (master off first) with the engine fire drill (fuel off first) - know which fire, which switch, first.
• Opening vents/windows too early during an active fire, feeding it air.

• Treating an in-flight fire as anything other than an immediate forced landing.

Extinguishers and equipment

• Handheld extinguishers on light aircraft are typically Halon or BCF-type, effective on electrical and small fuel fires - know your aircraft's type and location before you fly it.

Ditching and survival

Ditching means a controlled forced landing on water. It is rare but every PPL pilot must know the drill because survival time in cold water is short and the margin for error is thin.

Before you go

• Overwater flights need a plan: know the coastline, expected water temperature and how far you will be from land.
• Life jackets are required for single-engine aircraft flying more than a set distance from the shore (check the current ANO distance, commonly cited as beyond gliding distance of land), and a liferaft is strongly recommended for extended overwater legs, especially over 50 nm from land.
• File a flight plan or at least tell someone your route and ETA - this is what gets search and rescue looking in the right place.
• Wear the life jacket, do not just stow it. Inflating it inside the cabin before exit can trap you against the roof, so inflate only once clear.

The ditching sequence

• Squawk 7700 and transmit a MAYDAY with position, souls on board and intentions as early as possible - do this before you are too low or busy to speak.
• Aim to ditch parallel to the swell where possible, into wind if swell is not dominant, using the lowest safe descent rate.
• Fixed gear aircraft ditch gear-up; flaps as recommended by the POH to get the slowest safe touchdown speed.
• Doors should be unlatched or removed before touchdown - water pressure can jam them shut on impact, trapping occupants.
• Brace firmly on final approach.

After touchdown

• Get out fast. Most light aircraft float only briefly, and cabins can flood within seconds to a couple of minutes.
• Exit on the upwind or up-swell side away from any fuel spill, then swim clear before inflating the life jacket.
• Deploy the liferaft, attached to the aircraft by its painter line until you are certain the aircraft is sinking, then release it.
• Stay together, get everyone into or onto the raft, and conserve body heat - the classic HELP position (Heat Escape Lessening Posture) reduces heat loss if you are in the water alone.

Common mistakes

• Forgetting to broadcast a MAYDAY before ditching, leaving no clue to your position.
• Inflating life jackets too early, risking entrapment inside a flooding cabin.
• Landing downwind or across the swell instead of along it, which increases the chance of flipping or breaking up.
• Not briefing passengers on brace position, exits and life jacket use before the flight.

Cold water incapacitates quickly through cold shock, so speed of exit and getting out of the water (even onto an upturned float or raft) matters more than swimming ability.

Why noise abatement matters

Aerodrome operators and local communities care a lot about aircraft noise, especially at busy GA fields near housing. As a PPL holder you must know and follow published noise abatement procedures - ignoring them can get you reported, fined, or banned from an airfield.

Where to find the rules

• Noise abatement procedures are published in the UK AIP and on individual aerodrome charts/website pages.
• Always check NOTAMs and the aerodrome's own noise leaflet before flying circuits or local flights.
• Many airfields publish preferred runways, noise-sensitive routes to avoid, and minimum height rules that differ from the standard Rules of the Air.

Key numbers to know

• The general VFR minimum height rule (Rules of the Air) is 500 ft from any person, vessel, vehicle or structure, and over congested areas 1,000 ft above the highest fixed obstacle within 600 m, while remaining able to land clear in an emergency without danger to persons or property on the ground.
• Many noise abatement schemes ask pilots to maintain circuit height (commonly 1,000 ft QFE at GA fields, though this varies by aerodrome) until established on final, rather than descending early.
• Noise Preferential Routes (NPRs) exist at some airports and must be tracked accurately, particularly departure tracks that avoid overflying villages.
• Some airfields impose noise abatement circuit patterns - avoid low, tight, or wide circuits that increase engine power near noise-sensitive areas.
• Touch-and-go / continuous circuit training may be restricted at certain times (evenings, Sundays) or capped in numbers per hour - always check local orders.
• Some aerodromes set voluntary or mandatory minimum climb power reduction points, and ask pilots not to reduce power abruptly over villages.

Common mistakes

• Assuming standard Rules of the Air heights apply everywhere - local noise rules can be stricter.
• Flying a wide, low circuit that tracks over a noise-sensitive village instead of the published pattern.
• Doing unnecessary low approaches or go-arounds directly over housing when a wider circuit was possible.
• Forgetting that noise abatement applies to helicopters and microlights too, with their own published procedures.
• Not checking for time-based restrictions (e.g. no circuit training before 0800 local or after a certain evening cut-off).

Enforcement and compliance

• Non-compliance can lead to the aerodrome operator reporting the pilot, and repeated breaches can result in landing fee penalties or a ban.
• The CAA does not usually prosecute for noise alone, but persistent low flying or reckless flight can also breach the general low flying rules (Air Navigation Order), which the CAA does enforce.
• Good practice: brief noise abatement procedures as part of every pre-flight plan, just like frequencies and airspace.

Search and rescue (SAR) basics

If you're overdue or missing, the UK SAR system kicks in through the Aeronautical Rescue Co-ordination Centre (ARCC), run jointly with the Coastguard. Alerting relies on you doing the basics: filing a flight plan or at least telling someone your route and ETA, and closing it or letting them know you've landed.

There are three ICAO alerting phases, based on increasing concern:

• INCERFA (uncertainty phase) - no word within 30 minutes of the ETA, or the aircraft fails to make an expected contact.
• ALERFA (alert phase) - continued silence after further attempts to contact, or when an aircraft cleared to land hasn't landed within 5 minutes of the estimated time, and radio contact is unsuccessful.
• DETRESFA (distress phase) - reasonable certainty the aircraft and occupants are in grave danger, e.g. fuel is thought exhausted, or the aircraft has been reported crashing.

Emergency Locator Transmitters (ELTs)

Many aircraft carry an ELT, which transmits on 121.5 MHz and/or 406 MHz when triggered by a hard landing (g-switch) or manually. The 406 MHz signal is relayed via satellite (COSPAS-SARSAT) to the ARCC, giving a location fix, so it's much faster than 121.5 MHz alone. Know where your ELT switch is and how to activate it manually if the automatic trigger fails.

If you see distress signals or a crash

Standard visual distress signals include a succession of white flares or rockets, or SOS by any means. If you spot a downed aircraft or survivors, note the position (lat/long or a clear reference), remain in the area if fuel allows, and report to ATC or the nearest FIS/frequency without delay - don't just carry on and hope someone else saw it.

Accident and incident reporting

UK reporting sits with the Air Accidents Investigation Branch (AAIB), separate from any CAA enforcement action, because the aim is safety learning not blame.

• A reportable accident involves death or serious injury, or the aircraft sustaining substantial damage, and must be reported to the AAIB without delay - the pilot-in-command or aircraft operator is responsible.
• A serious incident (one that nearly resulted in an accident) is also reportable to the AAIB.
• Preserve the wreckage and evidence - don't move anything unless it's needed to free people, prevent further danger, or is required by authorities.
• Separately, Mandatory Occurrence Reports (MORs) go to the CAA for a wider range of safety-significant occurrences, not just accidents.

Common mistakes

• Confusing INCERFA/ALERFA/DETRESFA order, or thinking DETRESFA is the first stage rather than the last.
• Assuming 121.5 MHz ELTs give a satellite position fix - only 406 MHz does.
• Forgetting that accident reports go to the AAIB, not the CAA.
• Moving or disturbing wreckage after an accident when it isn't necessary.
• Not closing a flight plan after landing, which triggers a false alert.