General / Misc Nav stuff (NAV) Flashcards
What is the ICAO definition of navigation?
The process or method with which an aircraft is guided safely from its starting point to its destination, including determining the position of the aircraft, monitoring its flightpath and making any necessary corrections.
What are the 5 main components of navigation?
Position Course Time Altitude Distance
What is the standard scale of a VFR chart?
1:500,000
How flattened is the earth?
About 1/300
What is the mean circumference of the earth?
40,000km (21,600NM)
What is the mean radius of the earth?
6367km (3438NM)
What is the mean diameter of the earth?
12,735km (6876NM)
What is the rotational speed of the equator?
1670km/h (900kt) 15degrees/hour
What is the definition of a Nautical Mile?
The distance of any segment of any path describing a great circle of the earth which is intercepted by 1 arc minute measured from the centre of the earth.
How far is the Earth’s axis of rotation tilted? Where does this mean the tropics are?
23.5 degrees, making the tropics 66.5 degrees north and south of the equator.
How far does the Earth rotate in an hour? In 4 minutes?
15 degrees and 1 degree, respectively.
What is a geoid?
An equipotential surface (a surface across which gravity is the same) equal to mean sea level.
What is an ellipsoid, and what is the standard reference ellipsoid for aviation?
A mathematical model of a near-sphere, intended to be similar to the dimensions of the Earth. WGS 84 is the standard reference.
What is the name of the plane on which the Earth orbits the Sun?
The elliptical plane.
What are the two astronomical definitions of the year? Which is used in aviation?
The Siderial Year, which is the amount of time it takes an arbitrarily-distant star to return to the same position in the sky, and the Tropical Year, the amount of time it takes the Earth’s rotational axis to return to the same place relative to its orbital axis. The tropical year is the one we care about.
What is a “true solar day”?
The time between two successive lower culminations of the sun.
What is the single-letter code given for UTC?
Z.