Navigation Flashcards
True/false: When you cross the international date line flying westwards, one day is substracted from your date
False. Crossing the international date line westwards adds a day, whereas crossing eastwards substracts a day
How many knots are in 3 SF (speed factor)?
180 kts (60 kts in 1 SF)
The pressure at MSL (mean sea level) is 1000 hPa. If we climb to an altitude of 900 ft, what is our local pressure?
Approximately 970 hPa
Using 1 hPa per 30 ft:
900/30 = 30 hPa
1000 - 30 = 970 hPa
The 4 intercardinal points are: …
North, south, east and west
How many NM are between the following two positions
1: 42°18’N 153°59’E
2: 18°32’S 153°59’E
3650 NM
Remember that:
1° = 60 NM
1’ = 1 NM
What is a great circle?
A great circle is the path between two points on the globe with the shortest distance
What is a rhumb line?
A rhumb line is the path between two points on the globe where the azimuth is constant
True/false:
On a Lamberth conformal conic projection map, a rhumb line will be a curved line, whereas a great circle will be a straight line
True
True/false:
On a Cylindrical/Mercator projection map, a rhumb line will be a curved line, whereas a great circle will be a straight line
False. A rhumb line will be a straight line, whereas a great circle will be a curved line
If the IAS is kept constant, the TAS will (increase or decrease?) with an increase in altitude
Increase
If an aircraft is flying at 208 kts TAS, and the aircraft has a direct tailwind of 19 kts, what is the GS?
227 kts
What is navigation?
The art and science of determining the position of a ship, plane or other vehicle, and guiding it to a specific destination.
What are the three levels of organizational planning?
Strategic = long term
Tactical = short / medium term
Operational = Day to Day
On what level of organizational planning does ATC use navigation?
Primarily on the operational level, have the focus on guiding aspect
What is the tilt of the eart?
23,5 degrees
What gives us the seasons?
The tilt of the earth.
What is civil twilight?
Civil twilight ends in the evening when te centre of the sun’s disc is 6 degrees below the horizon and begins in the morning when the centre of the sun’s disc is 6 degrees below the horizon.
At which longitude do we find Greenwich Meridian Time / UTC?
0 degrees
What do we call the “anti-meridian”?
The International Date Line
Are latitudes always the same length?
No, they get shorter towards the poles.
How many seconds are there in 1 degree latitude? How many NM is this?
3600 seconds
= 60 minutes is equal to 60 NM
Is the distant between the same longitudes always the same if you move North?
No, the distance becomes smaller if you move North and depends on the latitude on which it is measured.
What is the reference system for the GPS system?
WGS84 = World Geodetic System 1984
What do we call the shortest distance you can fly between two points on eart?
A great circle.
Where is True North located on earth?
Where the longitudes converge.
Geographic north
To which north is the compass pointing?
Magnetic North
What do we call the lines on a chart that show the pattern of Magnetic declination (variation)?
Isogonic lines
What do we call de angle between True North and Magnetic North?
Variation
What is deviation?
The angle the compass in the aircraft deviates from magnetic north.
What is the type of chart we commonly see in the “classroom”?
A mercator projection chart.
Where is a mercator projection chart most precise?
Along the equator.
Which type of chart has a standard parallel?
A lambert projection chart
What is the definition of MACH
The ratio between the aircraft (TAS) and the local speed of sound (LSS)
Does the True Airspeed compensate for altitude and temperature?
Yes
How much time does it take an aircraft that is flying 240 kts GS to cover 80 NM?
80 / SF4 = 20 min
On which frequency band does the NDB operate?
190 - 1750 kHz
What do we call a NDB when it is used in conjunction with an ILS marker?
A “locator”
What is the typical range of a NDB-Locator and of a NDB en-route?
15-25 NM
20-500 NM
What are the operational uses of an NDB?
Area navigation
Non-precision approaches
To define routes/airways
What is the difference between a Relative Bearing Indicator (RBI) and a Relative Magnetic Indicator (RMI) when determine the direction to the NDB station?
With RBI the pilot has to calculate bearing to / from station, relative bearing is the angle between the A/C nose and the station.
With RMI bearing to/from station can be read off directly, magnetic bearing is the angle between the MN and MT to the station.
What are the 6 effect on precision with a NDB?
Electrical Interference - Thunderstorms
Station interference - Other electrical stations
Night effect - Reduced ionosphere at night
Terrain effect - Reflection ex. mountain
Coastal effect - Radio waves deflected slightly as they go through different air masses over land and water
Bank effect - a/c that is banking can block the signal
Is the VOR more accurate than a NDB?
Yes!
The VOR is limited to “Line of Sight”.
True or false?
True, because it is operation in the VHF band.
What is the cone of confusion with a VOR?
Directly above the station the VOR can hardly determine on which radial the a/c is flying.
What is the frequency band of the VOR?
108.00 - 117.975 MHz
Which instrument is used in the cockpit for receiving and interpreting the VOR signals?
The Course Deviation Indicator (CDI)
What is the frequency band in which the DME is operating?
The UHF band, between 962 and 1213 MHz
What is the max amount of aircraft that one DME can answer at the same time?
Around 200 aircraft at the same time.
What is the main difference between Type A and Type B approaches?
Type A will allow aircraft down to 250’ DA (H) / MAPt
Type B will allow aircraft below 250’ DA (H)
What is an Precision Approach?
Instrument approach procedure based on navigation systems designed for 3D instrument approach operations. Can both be Type A or B. Obstacle clearance is lower on PA than on NPA and APVs.
What are the different Decision Heights and Runway Visual Range in relation to the ILS categories?
CAT I ; 200 ft DH ; >550 m RVR
CAT II ; 100 ft DH ; > 300 m RVR
CAT II ; ? DH (can be zero) ; RVR beween 175 - 75 m
What are two Inertial systems?
Inertial Navigation System (INS)
Inertial Reference System (IRS)
What is an Inertial Reference System?
Nav system in an a/c. Self-sufficient system. Consist of laser gyros and accelerometers. Delivers position info to FMS and nav computer. Same function as GPS, just without satellites.
What is GBAS?
A GNSS reference receiver located “on sight” receives signals from orbiting satellites and can calculate the “error” in tome as it knows its own exact position. This error info is sent to a/c so the FMS can adjust the GNSS signal it receives. Only works within around 50 km of GBAS station.
What is SBAS?
A network of GNSS receivers determine the “error” in signal. The “error” signal is uplinked to a geo-stationary SBAS satellite. The SBAS satellite covers a greater area and transmits the “error” signal on the “normal” GPS frequency for all receivers with SBAS capability.
What is the SBAS system called in EU?
EGNOS
What are the obstacle clearances at the following segment in an Instrument Approach:
- Initial segment
- Intermediate segment
- Final segment
Initial segment: min of 984 ft (300 m)
Intermediate segment: min of 492 ft (150 m)
Final segment: 246 ft (75 m) with FAF; and 295 ft (90 m) without FAF
What is the climb gradient of a Missed Approach with a Instrument Approach?
2,5% climb gradient
What is the intermediate missed approach segment?
And the final missed approach segment?
Intermediate: 30 m (98 ft)
Final : 50 m (164 ft)
What are the 3 type of holding entries?
Direct
Teardrop / Off set
Parallel
What is the best non-precision approach?
A LLZ approach, has a high lateral accuracy. Descend is done in Vertical Speed with reference to dist/alt (time)
What is a circling approach?
An IAP procedure to bring the pilot within visual contact with the airport and landing runway. Often used when there is only IAP for one runway, but other runway is in use (because of wind for example)
What is a Visual approach when flying IFR?
The pilot concludes the approach and landing with visual reference to preceding traffic and terrain. Time and fuel saving. Still flying under IFR!
Difference between RNAV and RNP?
RNAV: without performance monitoring and alerting system
RNP: with performance monitoring and alerting system
Both are Performance Based Navigation (PBN)
What is the specified accuracy for RNAV and RNP?
95%
Are ILS CAT I, II and III IAP covered by PBN?
Nope
When should RNP approaches be available for all IAP runways according to EASA?
2024
What are the different RNAV categories?
1 - Departure, Arrival
2 - Enroute
5 - Enroute
10 - Oceanic
What are the different RNP categories?
0,3 - Final Approach
1 - Departure, Arrival
2 - Enroute
4 - Oceanic
