On 5 April at 0509 zone time, morning stars were observed and the vessel's position was LAT 28°32'N, LONG 177°13.0'W. Your vessel is steaming at 19.0 knots on a course of 258°T. A sextant observation of the Sun's lower limb is made at 1021 zone time. The chronometer reads 10h 20m 09s, and the sextant altitude (hs) is 58°06.6'. The index error is 1.0' off the arc, and the chronometer error is 00m 54s slow. Your height of eye on the bridge is 55.0 feet. What is the azimuth (Zn) of this sight using the assumed position?

Question

On 5 April at 0509 zone time, morning stars were observed and the vessel's position was LAT 28&deg;32'N, LONG 177&deg;13.0'W. Your vessel is steaming at 19.0 knots on a course of 258&deg;T. A sextant observation of the Sun's lower limb is made at 1021 zone time. The chronometer reads 10h 20m 09s, and the sextant altitude (hs) is 58&deg;06.6'. The index error is 1.0' off the arc, and the chronometer error is 00m 54s slow. Your height of eye on the bridge is 55.0 feet. What is the azimuth (Zn) of this sight using the assumed position?

Accepted Answer

Option C: 129.2&deg;T. Apply index error and dip correction to the sextant altitude to find Ho. Use the assumed position to solve the navigational triangle for the azimuth (Zn). Following the procedures in Bowditch, the calculated Zn for the Sun at the specified time and position is 129.2°T.