AERODROME OPERATIONS TRAINING – MODULE 2Aircraft Operations and Systems

LEARNING OUTCOMEParticipants will gain an overview of aircrafts

operations, and systems including: Principles of flight Propulsion systems Navigation systems and PerformanceWith access to performance graphs they will be

able to calculate take off and landing weights and payload range capability

PRINCIPLES OF FLIGHT NEWTONS 3 LAWS1. A body continues to maintain its state of

rest or of uniform motion unless acted upon by an external unbalanced force.

2. F = ma: the net force on an object is equal to the mass of the object multiplied by its acceleration.

3. To every action there is an equal and opposite reaction.

PRINCIPLES OF FLIGHTLIFT Bernoulli’s Theorem When the speed of a

fluid increases the pressure decreases Reaction to wing deflecting air downwards

PRINCIPLES OF FLIGHTLIFT and DRAG

Lift = Coefficient Lift x ½ (air density x v2 x S)

Drag = Coefficient Drag x ½ (air density x v2 x S)

PRINCIPLES OF FLIGHTLIFT – STALL ANGLE OF ATTACK

PRINCIPLES OF FLIGHTFOUR FORCES AIRCRAFT IN FLIGHT

Lift = WeightThrust = Drag

FLIGHT CONTROLS – 3 AXIS Lateral axis – pitch controlled by elevators Longitudinal axis – roll controlled by

ailerons Vertical axis – yaw controlled by rudder

FLIGHT CONTROLS

Flight controls vary the effective angle of attack of the given lifting surface thus varying the amount of force (lift) produced.

FLIGHT CONTROLS - FLAPS

Increase angle of attack and surface area thus enabling wingto produce more lift and drag at lower speeds (take-off/landing)

AIRCRAFT TURNINGRoll

Turn

PROPULSION SYSTEMS - PROPELLERS

Powered by either piston engine or gas turbine (turbo-prop)

Cross section an aerofoil like a wingbut varying pitch angle due to tip travelling faster than hub.

Fixed pitch compromise between take-off and cruise speed.Variable pitch enable optimum pitch setting thru out speed range

PROPULSION SYSTEM – TURBO-JET

Oldest form of jet engine, still in use for high speed aircraft suchas supersonic military aircraft.•Not efficient – high fuel consumption•High noise levels

PROPULSION SYSTEM – TURBO-FAN

High thrust levels, fuel efficient, quiet, limited mainly to sub-sonic

NAVIGATION SYSTEMS Basic: Compass, clock, maps, Dead-reckoning,

visual fixes

Ground Based Radio Aids: ADF/NDB, VOR, DME, ILS

Aircraft: Inertial Navigation System (INS)

Space: Global Navigation Satellite System (GNSS) or GPS

Integrated: Flight Management System (FMS)

NAVIGATION SYSTEM – NDB/ADF NDB- Non-Directional Beacon Ground based

subsystem Transmitting a simple radio signal on the M/F broadcast band. Signal follows curvature of earth so can be used at greater distances than line of sight navaids

ADF- Aircraft subsystem consisting of radio receiver and directional indicator showing relative bearing to NDB. When read in conjunction with compass a magnetic bearing can be established

Limitations: Outdate system subject to number of errors – Night, Terrain, Electrical, Coastline, Bank. High pilot work load (not able to be coupled to auto-pilot)

NAVIGATION SYSTEM - VORVHF Omni-directional Range (VOR)

Ground subsystem consists of a transmitterBroadcasting coded navigation signal on VHF108-117.95 MHz. 2 methods of transmitting Doppler and Conventional. Navigation signal aligned to magnetic north. Limited to line of sight.Aircraft subsystem consists of radio receiverand omni bearing selector (OBS) with CDI and To/From indicator. Desired course to/from the VOR is selected on OBS and CDI centres when on course.

NAVIGATION SYSTEM - ILS

Instrument Landing System (ILS) – Ground sub-systemConsists of two major components

Localizer providing azimuth guidancewith respect to the runway centreline. Localizer array installed on up wind end ofRunway and transmits signal in VHF band 108 – 111.95 MHzGlide-slope providing vertical flight path guidance normally 3° with 50ft thresholdCrossing height. Glide-slope antenna Installed abeam touchdown zone transmitsSignal in UHF band 329-335MHz.Ranging information is also providedBy DME or Marker beacons

NAVIGATION SYSTEM - ILS

ILS Aircraft Sub-systemILS is selected on same nav receiver as VOR withGS automatically selected to paired Localizer Frequency. ILS nav information displayed on same CDI as VOR but OBS is inhibited.

•Top display aircraft is on localizer course and on GS

•Centre left of localizer course and above GS

•Bottom right of localizer course and below GS

Category 1 minima down to 200ft – 800m visCategory 2 minima down to 100ft – 350m visCategory 3 A 50ft – 200m, B 0ft – 50m, C 0ft – 0m

NAVIGATION SYSTEM – DME & TRANSPONDER

Aircraft DME system interrogates ground station And times delay in reply which it displays as a slant Distance in NM to the station. Ground station normally co-sited with VOR or ILSATC transponder works in reverse to DME whereby ground secondary surveillance radar (SSR) interrogates aircraft transponder and times delay in response along with azimuth of bearing to display aircraft position to controller. Also able to send unique aircraft identifier (Mode A) and other info such as altitude (Mode C) and data (Mode S)

NAVIGATION SYSTEM - RNAVAREA NAVIGATION (RNAV)

Using ground based navaids requires aircraft to route via overhead the various navaids whereas RNAV capability permits directRouting.

Initially RNAV capability was limited to large jet aircraft equipped with INS and systemAccuracy only supported enrouteNav. GPS (GNSS) has now givenThis capability to all aircraft andenhanced accuracy to enableinstrument approaches similarto VOR/DME capability

RNAV - DEVELOPMENTS RNP: Required Navigation Performance – figure

of aircrafts nav Capability within 95% of time. • RNP 10 – Oceanic enroute, • RNP 4 – Domestic enroute• RNP 0.3 Non-precision approach BARO/VNAV modern aircraft capability of

vertical navigation profile Similar to ILS although not to same accuracy

GNSS: Augmentation systems GBAS, SBAS PBN: Performance Based Navigation – ICAO

strategy for managing the implementation of all of the above RNAV technologies

INTERNATIONAL STANDARD ATMOSPHERE

ISA is an atmospheric model of how the pressure, temperature, density, and viscosity of the Earths atmosphere change over a wide range of altitudes. Provides a standard to certify aircraft performance.

Height ft Temp °C Pressure hPa

Lapse rate °C/1000ft

0 15.0 1013.2 1.98

36,000 -56.5 226 0

AIRCRAFT CERTIFICATION Two main certification standards for air transport aircraft-• United States FAR 25• European JAR 25Both standards very similar and either acceptable for NZ CAA.Certification includes strict take-off and landing performance

requirements.

Air Operator Certification requires additional margins over the base certified performance as per CAR Part 121 Subpart D.

(b) Each holder of an air operator certificate shall ensure that, for each aeroplane it operates, the landing weight for the estimated time of landing at the destination aerodrome and at any alternate aerodrome allows a full stop landing on a dry runway from a point 50 feet above the threshold within— 60% of the landing distance available at the destination and at any alternate aerodrome for a turbojet or turbofan powered aeroplane;

TAKE-OFF PERFORMANCE

Take-off Run (TORA)SOT – VlofTake-off Distance (TODA)SOT – 35ftAccelerate/Stop (ASDA)SOT-V1- StopLanding Distance (LDA)50ft over THR

Balanced field length: TORA=TODA=ASDA

TAKE-OFF GRAPH

Calculate Max Take-off WeightRunway length 2000mSea LevelTemperature ISARunway DryFlaps 15

LANDING GRAPH

Calculate maximum landing weightRunway length 1814mSea levelRunway wet

PAYLOAD RANGE GRAPH

Calculate Available PayloadTake-off weight from slide 25Distance 2000nmOEW

PRACTICAL EXERCISE

1.Does the aircraft stall speed remain constant or vary with weight?

2.To roll the aircraft to the right requires the left aileron to go …..?

3.What ground navaid does the aircraft ADF utilise?

4.What is the aircraft relative position to the ILS course and glideslope from the CDI below?

PRACTICAL EXERCISE - PERFORMANCE1. Calculate the maximum take-off weight for a

Boeing 777-200 for Runway 2000m. SL given Temperature ISA +15, runway dry

2. Calculate the maximum payload for the above for a 3800nm flight using an OEW of 136,000kg

3. Calculate runway distance required to land an Airbus A320 at MLW given altitude 2000ft, runway wet.