Test Papers / Previous Question Papers of IGNOU BNS104A Navigation I-A June 2005

DIPLOMA IN NAUTICAL SCIENCE

Term-End Examination

June, 2005

BNS-104(A) : NAVIGATION I-A

Time: 2 hours
Maximum Marks : 70

SECTION I

1. Explain by means of sketches, Apparent Annual motion of the Sun and the concept of the Ecliptic and Obliquity of the Ecliptic, giving explanation underneath the figure. (10)

2. (a) Draw a figure on the plane of the equinoctial showing Celestial Meridians of Aries (γ), Greenwich, Observer and a Star indicating by curved arrows directions in which RA*, SHA*, GHA*, LHA*, GHAγ and Longitude are measured.

(b) To an observer, the Sun's LHA was 290^o, when its GHA was 40^o. Find the Observer's Longitude. (10)

3. Define : (5)

(a) Right Ascension
(b) Vertical Circle
(c) Rhumb Line
(d) Rational Horizon
(e) First Point of Aries

4. Sextant Altitude of Star Capella was found to be 23^o 12.7'. If the Index error was 1.2' off the arc, and height of eye was 11.00 m, find the true altitude of the star applying each correction separately. (10)

SECTION II

From a position 06^o 28' N 079^o 27' E, a vessel has to reach a position 9 miles due West of Colombo Light in 2 hours 30 minutes. Find course to steer and speed at which to steam. Wind NW ly estimated to cause a leeway of 3^o, current setting NE @ 3 knots. (10)

6. From a position 7.0 miles to the South of Dondra Head Lt. at 1900 hours, vessel steered 286^o(C), deviation 3^oW, variation 4^oE, ship's spead 13 knots. At the end of 2 hours, vessel found Point De Gaulle Lt. bearing 025^o (T) x 11 miles. Find the Set and rate of current during this period.

7. Draw symbols used on navigational charts to represent : (10)

(a) Castle or a fort
(b) Radar conspicuous object
(c) Power submarine cable
(d) Rock awash at Chat datum
(e) Natue of bottom

    (i) mud
    (ii) gravel
    (iii) stone
    (iv) sand
    (v) shingle

8. Find: (5)

(a) Compass error given : Deviation1^oE,
Variation 3^o E

(b) Deviation given : Compass error 5^oW,
Variation 2^o W

(c) Variation given : Compass error 2^oE,
Deviation 3^oW

(d) True Course given : Compass Course 357^o (C),
Variation 1^o E
Deviation 3^o W

(e) Compass Course given : True Course 001^o (T)
Variation 3^o W
Deviation 4^o E