Altitude Corrections

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Altitude Corrections
Quiz Q A

• Junior Navigation
• Chapter 4

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1. Dip correction is the angular difference
between the visible horizon and a true
horizontal. a. True b. False
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2. A ship's captain takes a sight from the ship's
rigging with a HE of 54 feet. His mate takes a
sight from the deck of the ship with a HE of 18
feet. For which HE will the dip correction be
greatest?
HE of 54 feet
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3. Find the dip correction HE
Correction 18 ft ____ 22 ft ____ 72
ft ____
-4.1' -4.5' -8.2'
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4. For the following data, determine main sextant
altitude corrections
Body Date ha Sun UL 21 June
17 32.1' Sun LL 29 Sept 43 46.0'
Sun UL 29 Sept 43 46.0' Sun LL 10
Mar 61 41.6'
Main -18.8' 15.0' -16.8' 15.7'
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Altitude Corrections JN Quiz Chapter 4 Problem
5 Refraction is minimal for a. daylight
observations. b. low-altitude sights. c. star
sights. d. high-altitude sights.
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Altitude Corrections JN Quiz Chapter 4 Problem
6 Parallax is minimal for a. daylight
observations. b. moon sights. c. star
sights. d. sun lower-limb sights.
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Altitude Corrections JN Quiz Chapter 4 Problem
7 The main correction for an Sun LL sight is
subtracted from ha. a. True b. False
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Altitude Corrections
End of Quiz Q A

• Junior Navigation
• Chapter 4