Ultra-light Aeroplane (ULTRA) flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Ultra-light maximum mass

Most authorities cap ultra-light empty or maximum mass near 300 kg for single-seat and 450-600 kg for two-seat aircraft, combined with a low stall speed. Confirm the exact national limit before flight.

Ultra-light airworthiness permit

A time-limited document confirming the aircraft meets the state's ultra-light standard and maintenance schedule. It must be valid and carried on board, together with registration and insurance.

Converging aircraft right of way

When two aircraft of the same category converge, the one with the other on its right gives way. A lower aircraft gives way to a higher one on final approach.

VMC minima below 900 m

Typically 5 km flight visibility and separation of 1500 m horizontally and 300 m vertically from cloud. States may vary these figures, so check the national rules.

Controlled airspace entry

An ultra-light normally needs a clearance or a specific exemption to enter classes A-D. Radio and transponder carriage depend on the airspace class and the state.

Closing a flight plan

A filed plan or flight note must be closed on arrival. Failure to close triggers search-and-rescue action, so report arrival promptly by radio or telephone.

Standard atmosphere values

Sea-level pressure 1013.25 hPa, temperature 15 °C, with a lapse rate of 2 °C per 1000 ft up to the tropopause near 36,000 ft. These values define ISA and pressure altitude.

Density altitude

Pressure altitude corrected for non-standard temperature. High density altitude reduces engine power and lift, lengthening takeoff and reducing climb rate, especially at high, hot airfields.

Cloud base from spread

Convective cloud base in feet AGL is roughly the temperature-dewpoint spread in °C multiplied by 400. A 5 °C spread gives a base near 2000 ft.

Stable versus unstable air

Stable air gives smooth flight, haze and layered cloud; unstable air gives thermals, gusts, showers and cumuliform cloud. The lapse rate compared with ISA indicates which prevails.

Cold front passage

A narrow band of heavy showers, squall lines, a sharp wind shift and a pressure trough at the surface. Conditions improve rapidly behind the front as cooler, drier air arrives.

Carburettor ice conditions

Can form at outside temperatures from about 0 to 25 °C with high humidity. Signs are falling RPM, rough running and a drop that carburettor heat only partly restores.

Wind correction angle formula

WCA ≈ (wind speed ÷ true airspeed) × sin(wind angle) × 57.3 degrees. Apply it to the true course to obtain the true heading, then correct for variation and deviation.

1-in-60 rule

An off-track error of 1 nm after 60 nm flown equals a 1° track error. Correction to destination equals track error multiplied by distance flown divided by distance remaining.

Variation east is least

Subtract easterly variation and add westerly variation when converting true heading to magnetic heading. Read the local variation from the chart, since it changes with position and time.

QNH versus standard pressure

Set QNH below the transition altitude to read altitude above mean sea level. Set 1013.25 hPa above the transition altitude to fly flight levels, and change over at the transition level.

Dead reckoning and pilotage

Dead reckoning derives position from heading, time, speed and wind. Pilotage confirms it from ground features. Use both together, with a chart folded to the next leg.

GNSS cross-check

Set the receiver datum to WGS-84 and check accuracy before flight. Treat GNSS as an aid: keep a chart and compass heading as the primary means of navigation.

Lift equation

Lift equals half the air density times speed squared times wing area times lift coefficient. Lift rises with the square of speed, so small speed changes have large effects.

Stall angle of attack

A stall occurs at the critical angle of attack regardless of speed, weight or bank. An aircraft can stall at high speed in a steep turn or abrupt pull-up.

Load factor in a turn

In a level turn, load factor equals 1 divided by the cosine of the bank angle. At 60° bank it is 2, raising the stall speed by about 41 percent.

Best glide speed

The speed at which total drag is minimum, giving the greatest glide range. It increases with weight, so adjust for a heavier load and fly it precisely in an engine failure.

Vx versus Vy

Vx is best angle of climb, giving the most height per ground distance for obstacle clearance. Vy is best rate of climb, giving the most height per unit time.

Ground effect

Within about one wingspan of the ground, induced drag falls and the aircraft floats. It may lift off below flying speed and then sink when leaving the cushion.

Crosswind component

Crosswind equals wind speed multiplied by the sine of the angle between the wind and the runway. A 20 kt wind at 30° gives about 10 kt of crosswind.

Centre of gravity limits

The CG must stay within the certified range. An aft CG reduces stability and pitch authority; a forward CG raises stall speed and lengthens the takeoff run.

Hypoxia onset

Symptoms begin near 10,000 ft in an unacclimatised pilot: euphoria, poor judgement, tingling and blue lips. Supplemental oxygen is normally required above 12,500 ft.

Hyperventilation versus hypoxia

Both cause dizziness and tingling. Hyperventilation improves with slower breathing; hypoxia does not. If in doubt, descend, use oxygen and treat it as hypoxia.

Carbon monoxide warning

Exhaust leakage through the heater causes headache, drowsiness and cherry-red lips. Shut the heater, open fresh-air vents, descend and seek medical help if symptoms persist.

Spatial disorientation

Without visual reference the vestibular system gives false sensations of bank and pitch. In cloud or at night, trust the instruments and maintain a standard scan.

IMSAFE self-assessment

Illness, Medication, Stress, Alcohol, Fatigue and Emotion. Any positive item means do not fly until it is resolved, since each degrades judgement and reaction time.

Aviate, navigate, communicate

The order of priorities in an emergency. Fly the aircraft first, then fix position and navigation, and only then transmit a MAYDAY with position, altitude, problem and intentions.