L
label |noun| a small piece of paper or cloth attached to an article with details of its owner, contents, use, destination, etc. / Hydraulic tubing has a label with the word HYDRAULIC. / - |verb| 1. to identify by using a label / Parts are labelled with the manufacturer’s name. / 2. to add identifying words and numbers to a diagram / There is a standard way of labeling the navigation vector. /
lack |noun| the absence of something or a need for something / The engine stopped because of a lack of fuel. /
lag |noun| a delay, especially the time interval between an input and the resultant output / There is a time lag between the piston moving down and the mixture flowing into the cylinder. /
Lambert’s projection |noun| a map projection of the earth based around two standard parallels of latitude.
laminate |noun| a sheet of man-made material made up of bonded layers / Direction of the fibers and types of cloth used in the laminate are all very important factors. / - |verb| to make by using bonded layers of material
lamp |noun| a small light - warning lamp > a small light, often red, which informs of a possible danger by lighting up / The switch is connected to a warning lamp on the instrument panel which will illuminate if the oil pressure falls below an acceptable minimum. /
land |noun| solid ground, as opposed to the sea / a large land mass such as Greenland / - |verb| 1. to set an aircraft onto the ground or another surface such as ice or water, after a flight - to force land the aircraft > to land the aircraft when it can no longer be kept in the air for any particular reason 2. to arrive on the ground after a flight / Flight BA321 landed at London Heathrow at 1030 hours. / Opposite: take off
land long |verb| to land after the target / touchdown zone. / They landed long because of the wind-shear and heavy rain. /
land short |verb| to land before the target / touchdown zone
landing |noun| the act of setting an aircraft onto the ground or another surface such as ice or water after flight / Take-off and landing are normally made into wind in order to reduce the length of the take-off and landing run. In order to achieve a safe landing in a cross wind, the correct techniques must be used. /
landing beacon |noun| a radio transmitter at an airfield that sends a beam to guide aircraft that are landing
landing beam |noun| a radio beam from a beacon at a landing field that helps incoming aircraft to make a landing
landing charges |plural noun| money paid to an airport authority by an operator or private pilot for landing an aircraft
landing distance available |noun| the actual length of a runway which can be used for landing and roll-out. This is a key consideration for pilots when considering which alternate airport to choose for a diversion, especially towards the beginning of a flight when the aircraft is heavy with fuel and if, for example, one engine is operating at idle resulting in the thrust reversers being unavailable or only partly available. All these factors will increase the landing distance required with the necessary safety margin and may be compounded by a wet or icy runway surface, which will reduce the braking coefficient and increase the stopping distance. In addition, the LDA may be reduced due to work being carried out on the runway. Abbreviation: LDA
landing field |noun| a place where aircraft can land and take off
landing gear |noun| same as undercarriage
landing pad |noun| same as helipad
landing run |noun| the distance on the runway from the touchdown point to the stopping point or taxiing speed
landing sequence |noun| the series of maneuvers (outbound track, base turn, inbound track) prior to landing
landing speed |noun| the lowest speed at which an aircraft must be flying in order to land safely
landing strip |noun| a specially prepared area of land for an aircraft to land on
landing weight |noun| the weight of an aircraft when it lands, which is made up of its empty weight, the weight of its payload, and the weight of its remaining fuel
landmark |noun| something on the ground which enables the pilot to know where he/she is, e.g. a noticeable building, bridge, coastal feature, etc. / Railway lines are usually useful landmarks. /
land-side |noun| the part of an airport farthest from the aircraft
lane |noun| same as air lane
lapse rate |noun| the rate at which temperature changes according to altitude - adiabatic lapse rate > the rate at which air temperature decreases as it rises above the Earth’s surface. / As the height increases, the temperature decreases. / (NOTE: It has been found that when dry or unsaturated air rises, its rate of fall of temperature with height (i.e. lapse rate) is constant at 3°C per 1,000 feet. Similarly, descending air warms by compression at that rate. This dry adiabatic lapse rate is normally referred to as the DALR. Air rising and cooling often reaches its dew point temperature, becomes saturated and any further cooling results in condensation and the release of latent heat. Release of latent heat delays the cooling process and the lapse rate at low levels is reduced to 1.5°C per 1,000 feet. This temperature change is called the saturated adiabatic lapse rate and is normally referred to as the SALR.)
largely |adverb| mainly, mostly / Heat is transferred from the Earth’s surface upwards largely by convection. The southern hemisphere consists largely of oceans. /
laser ring gyro |noun| an instrument that uses beams of laser light in a closed circuit to detect whether something is level or not
last |adjective| coming or placed after all the others - |verb| 1. to continue for a period of time / A gust is a sudden increase in wind speed above the average speed lasting only a few seconds. / 2. to stay in good or usable condition / A piston engine lasts longer if it is handled carefully and serviced regularly. /
latent heat |noun| heat taken in or given out when a solid changes into a liquid or vapor, or when a liquid changes into a vapor at a constant temperature and pressure - latent heat of fusion > the quantity of heat required to convert ice, at its melting point, into liquid at the same temperature - latent heat of vaporization > the quantity of heat required to convert liquid to vapor at the same temperature - latent heat of sublimation > the quantity of heat required to convert ice to vapor at the same temperature
lateral |adjective| referring to the side / Drift is the lateral movement of the aircraft caused by the wind. /
lateral axis |noun| the axis of the aircraft from wing tip to wing tip about which the aircraft pitches up and down.
lateral distance |noun| the distance related to the aircraft’s horizontal movement (heading, course, track) and the localizer part of the ILS
lateral track offset procedure |noun| the fact that in RVSM conditions aircraft often fly a few miles to the left or right of the actual route in order to increase separation
latitude |noun| the angular distance north or south of the Earth’s equator, measured in degrees, minutes and seconds, along a meridian, as on a map or chart, etc. / Parallels of latitude are imaginary circles on the surface of the Earth, their planes being parallel to the plane of the equator. The center of London is latitude 51°30’N, longitude 0°5’W. /
latter |adjective| referring to something coming at the end or finish - the latter part of the take-off run > the part of the take-off run immediately before the aircraft leaves the ground - |noun| the second of two things mentioned earlier. Opposite: former - of the Airbus A320 and A340, the latter is the larger aircraft > the A340 is the larger of the two
launch |noun| a small boat often used to transport people from a larger boat or ship to the shore - |verb| 1. to slide or drop a boat into the water to make it ready for use / While passengers are fitting life jackets, crew will open exits and launch the life-rafts. / 2. to force something into motion / to launch a rocket /
lavatory |noun| same as toilet
law |noun| 1. a basic principle describing a relationship observed to be unchanging between things while particular conditions are met 2. a set of agreed rules / aviation law /
layer |noun| 1. one horizontal part / The lowest layer of the atmosphere is called the troposphere. / 2. a thickness of something / Layers of fluid next to the surface over which it is flowing travels more slowly than layers further from the surface. /
layer cloud |noun| same as stratus
layout |noun| the way in which things are arranged - cockpit layout > the design of the cockpit and the particular placement of controls, instruments, etc.
LC |abbreviation| load controller
LCD |abbreviation| liquid crystal display
LDA |abbreviation| landing distance available
LDR |abbreviation| landing distance required
lead (1) / led / |noun| a very heavy soft metallic element. Symbol: Pb - lead-free > not containing lead / Low-lead or lead-free fuel is used in most modern piston engines. /
lead (2) / lid / |noun| 1. an electrical wire or narrow cable / A lead connects the monitor to the computer. / 2. - to take the lead > to take control of a situation / It is vital in any emergency situation that a crew member should take the lead. / - |verb| 1. to guide or show the way by going first / In an emergency situation the aircraft commander may lead his passengers to safety. In a smoke-filled cabin, floor lighting leads passengers to the emergency exit. / 2. to cause / In winter, the cold conditions often lead to frost and fog. Contraction of metal parts and seals can lead to fluid leakage. / (NOTE: leading – led)
lead-acid battery |noun| a system of lead plates and dilute sulfuric acid, used as a starter battery or traction battery
leading edge |noun| the front part of the wing which meets the oncoming air first / In icing conditions, ice may build up on the leading edges. /
leak |noun| the escape of liquid or gas from a sealed container, or the amount of liquid or gas that has escaped / Any failure of the aircraft structure may cause a leak of pressurized air which might be very difficult to cure. / - exhaust leak > an escape of exhaust gases - |verb| to escape from a sealed container / Fuel may leak from a fuel tank if the drain plug is not seated correctly. /
leakage |noun| the escape of liquid or gas from a sealed container / Any internal or external leakage of fuel will cause a reduction in the operating period. / (NOTE: Leak is normally used for an individual instance while leakage is used more generally: There is a fuel leak from the central tank; Fuel leakage is a safety hazard.)
lean |adjective| referring to a mixture in which the ratio of air to fuel is greater than usual / Moving the mixture control lever aft to the lean position reduces the amount of fuel mixing with the air. /
lean mixture |noun| a fuel/air mixture in which the ratio of air to fuel is greater than usual
LED |noun| a semiconductor diode that emits light when current is applied. LEDs are used in cockpit displays. Full form: light-emitting diode
lee |adjective|,|noun| which is protected from the wind / The air on the lee side is drier than that on the windward side. The flow of air over and to the lee of hills and mountains may cause particularly severe turbulence. / Opposite: windward
leg |noun| part of a flight pattern that is between two stops, positions, or changes in direction / An airfield traffic pattern is divided into take-off, crosswind leg, downwind leg, base leg and final approach. /
legal |adjective| lawful or within the law /Alcohol concentrations of 40 milligrams per 100 milliliters, i.e. half the legal driving limit in the UK, are associated with substantial increases in errors committed by pilots./
legal working time |noun| the maximum number of hours that a crew may work without a break. This is an important safety issue, as tired crews are much more likely to make mistakes. In the event of long delays, a crew may exceed its legal working time and be unable to ensure a flight.
legend |noun| a list explaining the symbols on a chart or a map / A legend is usually to be found at the edge or on the reverse side of most topographical charts. /
length |noun| 1. a measurement along something’s greatest dimension / The runway length is 3 kilometers. / 2. a piece of something that is normally measured along its greatest dimension 3. the extent from beginning to end 4. extent or duration, the distance between two points in space or time - the length of a briefing > how much time the briefing takes - the length of the working life of components > how long the components last - the length of a flight > 1. the time it takes to complete a flight / The length of the flight meant that there was no time for a meal to be served to the passengers. / 2. the distance of the flight in nautical miles or kilometers / The length of the flight is 100nm. /
lengthen |verb| to make long or longer / The mercury column shortens when cooled and, due to expansion, lengthens when heated. / Opposite: shorten
lengthwise |adjective|,|adverb| along the length of something
lengthy |adjective| 1. long, extensive / He wrote a lengthy report. / 2. long, which lasts for a long time (NOTE: Lengthy often suggests a meeting or explanation which is longer than necessary and therefore uninteresting.) - lengthy meeting > a long meeting - lengthy explanation > a long explanation
lens |noun| a normally round piece of glass with curved surfaces found in microscopes, telescopes, cameras, spectacles, etc.
lens-shaped cloud, lenticular cloud |noun| cloud with slightly outwardly-curved upper and lower surfaces
lessen |verb| to make less / Reverse thrust is used to lessen the loads on brakes and tires. Clean filters lessen the possibility of blockage. /
letdown |noun| the descent of an aircraft in preparation for landing, before the actual landing approach
level |adjective| 1. - level with at the same height or position as something else / In most light aircraft, the airplane will be in a climb if the engine cowling is level with the horizon. / 2. having a flat, smooth surface - a level runway > a runway without bumps, etc. 3. on a horizontal plane 4. steady, referring to something with no sudden changes - speak in a level voice > do not raise and lower the sound of your voice - the level tone of an engine > the unchanging sound of an engine - level head > clear thinking / It is essential that the crew keeps a level head in an emergency. / - |noun| 1. a position along a vertical axis / The tropopause is the level at which the lapse rate ceases to be so important. / - the fluid level in the reservoir > the point where the surface of the fluid reaches up to - high-level cloud > high-altitude cloud 2. a position on a scale 3. a relative amount, intensity, or concentration / A gas turbine engine has an extremely low vibration level. /
level off |verb| to start to fly level with the ground after climbing or descending, or make an aircraft do this
level 160 |noun| a flight level, corresponding approximately to a height of 16,000 feet. Flight levels are calculated based on atmospheric pressure read by a barometer at ISA (International Standard Atmosphere), i.e. 1013 hectoPascal, rather than actual distance above the ground or sea.
lever |noun| 1. a device with a rigid bar balanced on a fixed point and used to transmit force, as in raising a weight at one end by pushing down on the other / Push the lever fully up to activate the brake mechanism. Push the button to release the lever. / 2. a handle used to adjust or operate a mechanism / Feathering is accomplished by moving the pilot’s control lever. / - |verb| to move as with a lever / The door would not open so the emergency services had to lever it open with specialized equipment. /
LF |abbreviation| low frequency
LH |abbreviation| Left Hand; in aviation ‘Left Hand’ / ‘Right Hand’ are generally used to avoid confusion with ‘right’ meaning ‘correct’ and ‘left’ meaning ‘remaining’.
license |noun| a document which is proof of official permission to do or to own something (NOTE: Each license has its own specific requirements and privileges. In the UK, one of the fundamental differences between a Private Pilot’s License and other types of license is that the holder of a PPL is not allowed to fly for ‘hire or reward’, i.e. the pilot cannot receive payment for flying.)
license holder |noun| 1. a person who has a license 2. a leather case, etc., in which to keep the license document
license |noun| US same as licence - |verb| to give somebody a license or official permission to do or to own something
lie |verb| 1. to be in a flat position, often horizontal / Seat rails are attached to the floor beams and lie level with the flooring. / 2. to be situated / Great circles are represented by curves which lie on the polar side of the rhumb line. / (NOTE: Care should be taken with the verbs to lie, as defined here: lie – lay – lain; to lie meaning ‘not to tell the truth’: lie – lied – lied and lay, meaning ‘to put down’ as in ‘lay the book on the table’: lay – laid – laid.)
life jacket |noun| an inflatable device, sometimes resembling a sleeveless jacket, to keep a person afloat in water / Pull down the toggles to inflate the life jacket. /
life raft |noun| a small boat-like vessel for use on an emergency over water
life vest |noun| same as life jacket / You will find a life vest under your seat. /
lift |noun| 1. a component of the total aerodynamic force acting on an airfoil which causes an airplane to fly / In level flight, a lift force equal to the weight must be produced. The pilot can achieve maximum lift by pulling hard back on the controls. / 2. an electrically operated machine for moving people or goods between the floors of a building (NOTE: The US English is elevator .) - |verb| to move to a higher position / A foot-pound is the ability to lift a one pound weight a distance of one foot. / (NOTE: Bernoulli’s principle states that if the speed of a fluid increases, its pressure decreases; if its speed decreases, its pressure increases. Wings are shaped so that the high-speed flow of air that passes over the curved upper surface results in a decrease in pressure. Lift is created because of the pressure differential between upper and lower surfaces of the wing. Lift is also created because the angle of attack allows the airflow to strike the underside of the wing. Daniel Bernoulli (1700–82) was a Swiss scientist.)
lift dumper |noun| a function of the ground spoilers on the upper surface of the wing during landing to reduce the lift of the wing and improve wheel brake traction, the lift dumper mode of the spoilers is armed before landing
light |noun| 1. brightness produced by the sun, the moon, a lamp, etc. 2. electromagnetic radiation which can be sensed by the eyes - artificial light > light made by using electrical, gas, etc., power 3. a source of light such as a lamp / Switch off the navigation lights. / - |adjective| 1. without much weight, not heavy / Aluminum is a light metal. / 2. of little force or requiring little force - a light wind > a gentle wind - light controls > flying controls which do not need much pilot effort to move them 3. of little quantity / light rain, light snow / 4. of thin consistency - light oil > oil which pours easily
light aircraft |noun| a small, single engine aircraft generally for private not commercial use
lighting |noun| lights or a system of lights / Cabin lighting is switched off for take-off and initial climb. Emergency floor lighting guides passengers to the emergency exits. /
lightning |noun| a powerful and sudden electrical discharge from a cloud / Lightning is the most visible indication of thunderstorm activity. /
lightning activity |noun| a period of time when there are a lot of lightning flashes
lightning strike |noun| the hitting of something by a discharge of lightning
light plane |noun| US same as light aircraft
likely |adjective| probable - rain is likely > rain will probably fall - icing is likely to occur in cumulonimbus clouds > icing is often a problem if flying in cumulonimbus clouds
limit |noun| a point or line past which something should not go / There is a time limit of one hour for the examination. The minimum age limit for holding a PPL in the UK is 17. / - the upper limit of cloud > the highest point at which there is cloud - |verb| to restrict or to prevent from going past a particular point / The amount of cabin baggage is limited to one bag per passenger. /
limitation |noun| the act of limiting or the state of being limited / Limitation of the maximum engine rpm to a little above maximum engine cruise rpm prevents compressor stall at the higher rpm range. /
line |noun| 1. a thin continuous mark as made by a pencil, pen, etc. or printed / Draw a line from point A to point B. / 2. a real or imaginary mark placed in relation to points of reference / An isobar is a line joining points of equal pressure. / 3. a long row of people, etc. 4. a row of written or printed words 5. a telephone connection to another telephone or system 6. an electrical cable or wire - telephone line > cable supported on pylons from one telephone exchange to another / On final approach to an unfamiliar airfield, pilots of light aircraft should keep a sharp lookout for power lines and telephone lines. / 7. a system of pipes 8. a company which owns and manages a system of transportation routes
linear |adjective referring to a line, straight / Although air may appear to be still or calm it is, in fact, moving west to east in space, the linear velocity being zero at the poles and approximately 1,000 mph at the equator. / - linear scale > a horizontal or vertical straight-line, rather than circular, scale on an instrument
linear actuator |noun| an actuator which operates in a straight back and forth manner, e.g. to open undercarriage doors
line feature |noun| a useful navigational landmark, e.g. a railway line, road or river
line maintenance |noun| an aircraft maintenance performed at the flight line or ramp between two flights
line mechanic |noun| an aircraft mechanic or engineer who inspects and services the aircraft (engine oil levels, tire pressure and wear, signs of fuel or hydraulic leaks, impact damage to the engine air intakes, fan blades and wing leading edges etc.), performs any small repairs and makes entries in the aircraft technical logbook
line of position |noun| same as position line
line of sight |noun| a clear path between sending and receiving antennas. Abbreviation: LOS
line up |verb| to move aircraft into position ready for departure / Line up with the nose-wheel on the runway center line. /
line-up check |noun| this check performed by the flight crew involves checking the identity of the runway and the departure clearance
link |noun| 1. a connection / Light aircraft can be steered while taxiing via a direct link from rudder pedals to nose-wheel. / 2. a relationship / There is a link between alcohol abuse and pilot error resulting in accidents. / - |verb| 1. to make a connection, to join / The connecting rod links the piston to the crankshaft. / 2. to establish a relationship between two situations / They link alcohol abuse and pilot error. /
linkage |noun| a system or series of mechanical connections such as rods, levers, springs, etc. / The linkage from the control column to the control surfaces should allow full and free movement. /
liquid |adjective| having a consistency like that of water / Liquid oxygen is stored in cylinders. / - |noun| a substance with a consistency like water / Water is a liquid, ice is a solid. /
liquid crystal display |noun| liquid crystals that reflect light when a voltage is applied, used in many watch, calculator and digital displays. Abbreviation: LCD
liquid fire |noun| oil or petrol fire
list |noun| a series of names, words, things to do, etc., arranged one after the other in a vertical column - |verb| to write a series of names, words, etc. one after the other in a vertical column / List the advantages of a stressed-skin construction. /
liter |noun| US same as litre
lithium |noun| a soft silvery metallic element, the lightest known metal, often used in batteries
litmus |noun| a substance which turns red in acid, and blue in alkali
litmus paper |noun| small piece of paper impregnated with litmus to test for acidity or alkalinity
litre |noun| the volume of one kilogram of water at 4°C (= 1,000cc or 1.76 pints) (NOTE: It is written l after a figure: 10l; also written liter in US English.)
live |adjective| carrying electricity / live wire /
livery |noun| the color scheme and markings on the outside of an aircraft that identify it as belonging to a particular airline
LMT |abbreviation| local mean time
load |noun| 1. the weight or mass which is supported / The load on the undercarriage decreases as lift increases and, when the aircraft rises into the air, the aircraft is supported by the wings. / - load bearing > supporting some weight 2. a force which a structure is subjected to when resisting externally applied forces / The load on the control column is increased when the aircraft is flown out of trim. / 3. something that is carried in the aircraft - passenger load > the number of passengers on board 4. the power output of a generator or power plant 5. the resistance of a device or of a line to which electrical power is provided - |verb| 1. to put something into a container, often for the purpose of transportation / The aircraft is loaded with fuel before take-off. / 2. to transfer data from disk into a computer main memory / She loaded the software onto the computer. /
load-bearing structure |noun| a structure which supports the weight of the aircraft in flight or on the ground
load controller |noun| a device which monitors the output of a generator
load factor |noun| the stress applied to a structure as a multiple of stress applied in 1g flight / The higher the angle of bank, the greater the load factor. / (NOTE: In straight and level, constant speed flight, the load factor is 1. When an aircraft turns or pulls up out of a dive, the load factor increases. An aircraft in a level turn at a bank angle of 60 degrees has a load factor of 2. In such a turn, the aircraft’s structure must support twice the aircraft’s weight.)
load manifest |noun| a detailed list of the cargo on a flight. Also called: load sheet
load shed |noun| the disconnection of non-essential electrical power users (notably the galley) if there are electrical generation failures in order to give priority to the essential systems
load sheet |noun| same as load manifest
loading |noun| 1. the act or process of adding a load to an aircraft - loading is in progress > passengers, baggage, freight, etc., are being put on the aircraft 2. the total aircraft weight or mass divided by wing area / Inertia switches operate automatically when a particular g (acceleration due to Earth’s gravity) loading occurs. / 3. a force or stress acting on an object - centrifugal loading > centrifugal force acting on something / Centrifugal loading moves the valve towards the closed position. / 4. the act of transferring data from disk to memory / Loading can be a long process. /
loading bridge |noun| a covered walkway from an airport departure gate that connects to the door of an aircraft, used by passengers and crew getting on and off the aircraft
load-master |noun| the person who is in charge of the work of loading cargo onto a military or commercial transport aircraft
lobe |noun| one of two, four or more sub-beams that form a directional radar beam / Any system employing beam sharpening is vulnerable to side lobe generation at the transmitter. /
LOC |abbreviation| localiser
local |adjective| not broad or widespread - local meteorological conditions > weather conditions in the restricted area of a particular place
local time |noun| a time used at a given geographical location or in a time zone as opposed to Universal Coordinated Time or GMT. Abbreviation: LT
local authority |noun| a government body responsible for the various services of an area
localized |adjective| restricted in area or influence - a localized fire > a fire which has not spread
localiser, localizer |noun| a component of the instrument landing system that provides horizontal course guidance to the runway / If, during the approach, the aircraft deviates beyond the normal ILS glide-slope and/or localiser limits, the flight crew are alerted. / Abbreviation: LOC
locality |noun| a small geographical area / The highest point in a locality is marked by a dot with the elevation marked alongside. /
localizer beam front course |noun| the course indicated by the localizer transmitter antenna along the approach path of the aircraft
local mean time |noun| the time according to the mean sun. Abbreviation: LMT
local time |noun| the time in the country you are talking about
locate |verb| 1. to find the position of / Survival beacons transmit a signal which enables search aircraft/vessels to rapidly locate accident survivors still in the sea. / 2. to position / The digital flight data recorder is located in the tail section. /
location |noun| 1. a place where something can be found / Before take-off, cabin staff brief passengers on the location of emergency exits and life jackets. / 2. finding where something is / Rapid location of survivors is important. /
locator |noun| a non-directional beacon used as an aid to final approach / Terminal control areas require charts which show detail on a large scale – terminal VORs, locator beacons, ILS installations, holding patterns, arrival/departure and transit routes. /
lock |noun| a device operated by a key for securing a door, etc. - |verb| 1. to secure a door by turning a key in the lock / Lock the door before leaving the building. / 2. to be in or to move into a secure position 3. to block or prevent moving / Anti-skid braking systems units are designed to prevent the brakes locking the wheels during landing. / 4. - to lock on > to search for, find and follow a target with a thin radar beam
locking pin |noun| a short metal device to prevent a nut from turning
log |noun| a written record of a flight, flying hours, maintenance checks, etc., for an aircraft, engine or propeller - |verb| to write an entry in a log book or on a log sheet / He calculates headings to steer for each flight stage and logs them. /
logic |noun| electronic circuits which obey mathematical laws / Circuit packs consist of basic decision-making elements, referred to as logic gates, each performing operations on their inputs and so determining the state of their outputs. /
logical |adjective| referring to something which, because of previous experience or knowledge, is natural or expected /Pre-flight checks on light aircraft are made in a logical manner from one side of the aircraft to the other./
longeron |noun| the main structural part of an aircraft fuselage extending from nose to tail / Longerons are normally used in aircraft which require longitudinal strength for holds underneath the floor. /
long-haul |adjective| traveling over a long distance / Crew flying long-haul routes have to adapt to time changes. / Opposite: short-haul
longitude |noun| the angular distance on the Earth’s surface, measured east or west from the prime meridian at Greenwich, UK, to the meridian passing through a position, expressed in degrees, minutes, and seconds / The center of London is latitude 51°30’N, longitude 0°5’W. /
longitudinal |adjective| in a lengthwise direction
longitudinal axis |noun| the axis of the aircraft which extends from the nose to the tail.
long-range |adjective| 1. covering a long distance / long-range radar / 2. - long-range weather forecast > covering a period more than 5 days ahead
lookout |noun| a careful watch / Keep a careful lookout for other aircraft. / - to be on the lookout for > to watch carefully for something
loop |noun| a flight maneuver in which the aircraft rotates, nose up, through 360° while holding its lateral position
loop antenna |noun| circular-shaped conductive coil which rotates to give a bearing to a ground station
loose |adjective| not correctly attached or secured, detached, unfastened / There are loose pieces of plastic blowing around the apron. One of the pallets is loose. /
LORAN |abbreviation| long-range air navigation system
lose |verb| not to have something any longer (NOTE: losing – lost) - to lose altitude > to descend from higher to lower altitude
loss |noun| no longer having something / The pilot reported loss of engine power. / - loss of control > no longer being able to control - loss of life > death in an accident - loss of a signal > disappearance of a signal / The term attenuation means the loss of strength of a radio signal. /
loudspeaker |noun| an electromagnetic device that converts electrical signals into audible noise. Also called: speaker
lounge |noun| - VIP lounge > a special room at an airport for VIPs.
louvre |noun| thin, horizontal openings for air cooling / Cold air can be let into the cabin through adjustable louvres. / (NOTE: The US spelling is louver.)
low |adjective| 1. not high, not tall - low cloud > cloud relatively near the surface of the earth - low ground > an area of land which is not high, as opposed to mountains 2. not high, or below normal - low temperature > a temperature which shows that it is cold 3. quiet, not loud - |noun| an area of low atmospheric pressure - polar low > an area of low atmospheric pressure over polar regions
low frequency, low frequency band |noun| a radio communications range of frequencies between 30–300 kHz. Abbreviation: LF
low pass |noun| a flight at low altitude in landing configuration above the aerodrome usually so that the Tower controllers can check whether the landing gear seems correctly extended and locked down
lower |adjective| 1. referring to something that is at a low level or towards the bottom - the lower surface of the wing > the underneath surface of the wing 2. referring to something which is below something else of the same sort / Air is cooler high up than at lower levels. / Opposite: upper - |verb| 1. to let down to a lower position - lower the undercarriage > move the undercarriage into position ready for landing - lower the flaps > set the flaps to a down position 2. to reduce in amount or intensity - to lower the temperature > to reduce the temperature - to lower the pressure > to decrease the pressure - to lower the volume (of sound) > to make something such as a radio quieter or less loud
lower airspace |noun| the airspace below FL245 (approximately 24,500 ft)
lower atmosphere |noun| the layer of the atmosphere in which changes in the weather take place. Also called: troposphere
lower cargo deck |noun| a space below the cabin floor which is divided into a forward and aft cargo hold and which on larger aircraft may be subdivided into compartments. The holds / compartments are subdivided into bays each one of which corresponds to the size of a ULD or container.
lower level |noun| a lower flight level which the crew wishes to descend to for operational, technical or meteorological reasons
LT |abbreviation| Local Time
lubricate |verb| to oil or to grease moving parts in order to reduce friction / Oil passes through the hollow crankshaft to lubricate the big-end bearings. Turbo chargers are lubricated by the engine oil system. /
lubrication |noun| the act or process of covering moving surfaces with oil or grease in order to reduce friction - lubrication system > the tank, pipes, pumps, filters, etc., which together supply oil to moving parts of the engine
luggage |noun| baggage, i.e. cases and bags that somebody takes when traveling
