Why is the inertial navigation system combined with celestial navigation system?

Deriving true north

Deriving magnetic north

Correction for weather effects

Correction of drift error

Correct Answer : Correction of drift error

Explanation : Inertial navigational suffer from drift after long hours of using. Since the position error growth of these free inertial navigation systems was excessive on long flights, it was natural to periodically update their position with position updates from manual star fixing.

Recently Updated in Avionics Questions

Anti reflection coated optics reduce ________

Refraction

Reflection angle

Intensity of star image

Optical transmission losses

Correct Answer : Option (D) : Optical transmission losses

Explanation : For anti-reflection coated optics, the optical transmission losses may be 1% or 2% at each air to glass or glass to air optical control surface within the telescope, including windows or sensor covers or surfaces. For uncoated optics, the loss per surface is about 4% to 5%.

The ratio of the focal length to aperture is called the ________

Focal number

f/ number

Critical aperture

Effective aperture

Correct Answer : Option (B) : f/ number

Explanation : The ratio of focal length to aperture is called the f/ number. For example, an f/10 telescope may have a 30 in. focal length and a 3 in. aperture.

The physical size of the star depends upon _____

Shape of image

Colour of image

Angular size of image

Intensity of image

Correct Answer : Option (C) : Angular size of image