Navigation Flashcards
What is the axial tilt of the earth?
23.5 Degrees
What are longitude lines?
Meridians of Longitude are lines that join True North and True South Poles
At what longitude is the Prime Meridian?
0 degrees longitude
How is longitude referenced?
East or West of the Prime Meridian up to 180 degrees. Therefore there is the Anti-Meridian opposite the Prime.
What are latitude lines?
Parallels of Latitude are lines that circle the earths surface at right angles to lines of longitude and are parallel to each other.
How is latitude referenced?
North or South from the equator, which exactly half way between the True North and True South Poles. Therefore the maximum value is 90 degrees.
How is a position on the earth reference using longitude and latitude?
By using degrees, minutes and seconds.
60 seconds in a minute and 60 minutes in a degree.
Rather than writing sections, it is also possible to write fractions of a minute.
How is a nautical mile defined?
An angle of one minute of latitude. (1/60th of a degree)
What is a great circle?
The shortest distance between two points on the earths surface. They cross meridiants of longitude at different angles.
What is a rhumb line?
Cross all meridians of longitude at the same angle
What is an isogonal?
Lines of equal magnetic variation
What is variation?
The difference in bearing between True North and Magnetic North
What is a sideral day?
The time taken for the earth to complete one rotation. Ie for one meridian to rotate 360 degrees in line with a fixed point in space.
23 Hours 56 minutes
How long is the mean day?
24 Hours
How long does it take for the earth to rotate 15 degrees?
1 hour.
15 degrees longitude = 1 hour
(360/24)
Will east or west be ahead or behind UTC?
East will be ahead
West will be behind
What is conformity on a map?
Where directions/bearings are accurate. Ideally latitudes and longitudes should cross each other at 90 degrees.
What is equivalence on a map?
When the scale of the map does not vary
What does a straight line on a lambert conformal conic projection represent?
Great Circle
What does a straight line on a mercator projection represent?
Rhumb Line
What is 1nm in miles?
1.15 miles
What is 1nm in km?
1.852km
What is 1nm in ft?
6080ft
What is 1m in ft?
3.28ft
What is 1m in inches?
39 inches
What projection is on a half mil chart?
Lambert Conformal Conic Projection
What projection is on a quarter mil chart?
Transverse Mercator
What is the minimum height for an obstruction to be shown on a chart?
328ft (100m)
What is Track Made Good?
The actual track of the aircraft across the ground
What is drift?
The difference between heading and required track.
(Where the nose is pointing vs where its going)
What is Track Error?
The difference between Track Made Good and Required Track
What height reference is QNH?
Altitude. Height above mean sea level.
What height reference is QFE?
Height. Altitude above the aerodrome reference point.
What is ASR and PSR?
Altimeter Setting Region (ASR) in which the pressure setting given to pilots is the Regional Pressure Setting (RPS), which is the lowest forecast setting for the next 2 hours.
How does temperature affect altimetry?
Warm air is less dense than cold air, so for the same pressure, a column of warm air is taller than a column of cold air and pressure levels are therefore more widely spaced.
What are the two steps involved in calculating your True Altitude?
Determining Pressure Altitude
Correct current altitude for differences to ISA pressure
Determining True Altitude
Correct pressure altitude for differences to ISA Air Temperature
Does the compass suffer from dip closer or further away from the poles?
More Dip is present closer to the poles, at high latitudes
What is the compass mnemonic for turns using the compass?
UNOS
Undershoot North
Overshoot South
What is the definition of night?
ANO “The period from half an hour after sunset until half an hour before sunrise”
ICAO “The hours between the end of evening civil twilight and the beginning of morning civil twighlight. Civil twilight ends in the evening when the centre of the suns disc is 6 degrees below the horizon, and begins in the morning when the centre of the suns disc is 6 degrees below the horizon.”
What are the crosswind calculation rules of thumb?
30 Degrees off the nose = 1/2 the strength of wind is crosswind
45 Degrees off the nose = 3/4 the strength of wind is crosswind
60 degrees off the nose =
100% the strength of wind is the crosswind.
Clock Code
30 mins = 1/2 hour
45 mins = 3/4 hour
60 mins = Whole hour
What is 1 imperial gallon in US Gallons and Litres?
1 Imperial Gallon = 1.2 US Gallons = 4.5 Litres
What is MAUW or MAUM?
Maximum All Up Weight/Mass
The maximum weight allowed for the aircraft
What is Basic Empty Weight?
The weight of an unloaded and unfuelled aircraft.
What is payload?
The load carrying capability of the aircraft, which only includes passengers, baggage and cargo.
Pilot, Crew and Fuel is NOT included in payload.
Calibrated Airspeed is the indicated airspeed corrected for which two factors?
Position Error and Instrument Error
What should your minimum height be for a route?
500ft above the highest obstacle 5nm of each side of the track OR 800ft above the highest ground 5nm each side of the track whichever is higher
What is the formula for calculating track error?
Distance Off Track (nm) / Distance Gone (nm) = 60
What frequency bands are NDBs on?
Low/Medium frequencies
What frequency bands are VOR/ILS/DMEs on?
Very High Frequencies
What Interference errors do NDBs suffer from?
Night Effect
Coastal Refraction
Quadrantal Error
Do high or low power NDBs have larger range?
Long Range NDB = High Power
Short Range NDB = Low Power
How do NDBs propogate?
Via Surface Wave
How do VHF/UHF propgate?
Via line of sight (Space Wave)
What is DOC?
Designated Operational Coverage
What are the VDF bearing classifications?
Class A +/- 2 Degrees
Class B +/- 5 Degrees
Class C +/- 10 Degrees
Class D worse than C
What are QDM, QDR, QUJ and QTE?
QDM = Magnetic Heading TO the station
QDR = Magnetic Heading FROM the station
QUJ = True bearing TO the station
QTE = True bearing FROM the station
What are QDM and QTE best used for?
QDM - For homing TO a ground station
QTE - For position fix FROM a ground station (eg on a chart)
When using ADF for an NDB does the neede point towards or away from the beacon?
The aircraft receiver needle always points towards the beacon irrespective of aircraft heading
Is there a failure warning when using ADF?
No
Is a Radial from or TO a VOR?
FROM
How many satellite signals are requred for a position fix by the GNSS receiver?
4
What is RAIM?
Receiver Autonomous Integrity Monitoring is a technology developed to assess the integrity of GPS signals in a GPS receiver system. With “surplus” satellites faults can be detected.
Since 4 are required for GNSS position, 5 satellite signals are required to detect a fault.
