© Capt. Yusuf ZOR BA 1 BA, Secondary Port Capt. Yusuf ZORBA

© Capt. Yusuf ZOR BA 2 BA, Secondary Port You learned that how can you calculate tide times and heights for a specific port. Also, you learned that how can you calculate tide times and heights for secondary ports by US Tide Tables. Our aime for this pratice; –Using Tide Tables for Secondary Port in British Admiralty –Finding HW and LW times for Secondary Port –Finding HW and LW heights for Secondary Port

© Capt. Yusuf ZOR BA 3 BA, Secondary Port

© Capt. Yusuf ZOR BA 4 BA, Secondary Port The method of finding the time and heights of HW and LW at any Secondary Port given in the Admiralty Tide Tables is by means of simple differences in times and heights from predictions for the Standart Port indicated, which is the most suitable, Standart Port.

© Capt. Yusuf ZOR BA 5 BA, Secondary Port Example 1: Find the times and heights of HW and LW at Richborough for the PM rising tide on March, 02, Find the secondary port in the Geographical Index at the back of ATT (Adm. Tide Table). Note its number. Richborough : Find the Standart Port names and numbers in ATT, Part I Dover : 89

© Capt. Yusuf ZOR BA 6 BA, Secondary Port 3. Find the HW and LW times and heights at the Standart Port for the required day. Enter in tables (called NP 204), boxes 1 to 4 and calculate the range for box 5.

© Capt. Yusuf ZOR BA 7 BA, Secondary Port 3. Find the HW and LW times and heights at the Standart Port for the required day. Enter in tables (called NP 204), boxes 1 to 4 and calculate the range for box 5. Standart Port HW LW HW LWRANGE Seasonal Change Std. Port Differences Seasonal Change Sec. Port Secondary Port Duration

© Capt. Yusuf ZOR BA 8 BA, Secondary Port 4. Seasonal Change in Mean Level table from Part II, using its number and month find the Standart Ports Seasonal Change. Seasonal Changes In Mean Level for number 89 and 99 is same; -0,1 We change its signed, because of Standart Port heights include the Seasonal Change. Standart Port HW LW HW LWRANGE Seasonal Change Std. Port 66 Differences Seasonal Change Sec. Port 11 Secondary Port Duration

© Capt. Yusuf ZOR BA 9 BA, Secondary Port 5. Note the time and height differences for the secondary port and the related reference times and reference heights at the Standart Port.

© Capt. Yusuf ZOR BA 10 BA, Secondary Port 6. Interpolate between Secondary Port time differences and height differences.

© Capt. Yusuf ZOR BA 11 BA, Secondary Port 6. Interpolate between Secondary Port time differences and height differences. Interpolation methods: 1. Using graph paper 2. Using mathematical methods

© Capt. Yusuf ZOR BA Using graph paper for interpolation;

© Capt. Yusuf ZOR BA Using graph paper for interpolation; m 2.0 m 4.0 m 6.0 m

© Capt. Yusuf ZOR BA 14 Standart Port HW LW HW LWRANGE Seasonal Change Std. Port 66 Differences Seasonal Change Sec. Port 11 Secondary Port Duration Using graph paper for interpolation;

© Capt. Yusuf ZOR BA Using graph paper for interpolation; m 2.0 m 4.0 m 6.0 m For 6.1 For 1.6

© Capt. Yusuf ZOR BA 16 BA, Secondary Port Standart Port HW LW HW LWRANGE Seasonal Change Std. Port 66 Differences Seasonal Change Sec. Port 11 Secondary Port Duration :15 00: And we complete in boxes 7, and 8, 9, 10.

© Capt. Yusuf ZOR BA Using mathematical methods We will make a interpolation for secondary port differences. For times; 12:00 to 18:00 if +00:15 to +00:15 And our HW time is 15:11 we can say that is same (+00:15) 07:00 to 13:00if +00:30 to +00:30 And our LW time is 10:13 we can say that is same (+00:30) And we enter this results into boxes #7 and #8.

© Capt. Yusuf ZOR BA Using mathematical methods We will make a interpolation for secondary port differences. For heights; For HW5.3 to 6.8 if – 2.6 to – 3.4 and our height is 6.1= (0.8 x 0.8)/1.5 = 0.46 so, our differences for HW (-2.6)+(-0.46)= ~ -3.1 For LW0.8 to 2.1 if – 0.7 to – 1.7 And our height is 1.6= (0.8 x 1.0)/1.3 = 0.62 And our differences for HW (-0.7)+(-0.62)= ~ -1.3

© Capt. Yusuf ZOR BA 19 And we complete in boxes 7, and 8, 9, Using Secondary Port number to locate the right line, find and enter the Secondary Ports Seasonal Change for the month in boxes 11. Richborough : Apply differences to Standart Port times and heights to find times at the Secondary Port (boxes 12-15) BA, Secondary Port Standart Port HW LW HW LWRANGE Seasonal Change Std. Port 66 Differences Seasonal Change Sec. Port 11 Secondary Port Duration :15 00: :2610:

© Capt. Yusuf ZOR BA 20 BA, Secondary Port Example 1: Find the times and heights of HW and LW at Richborough for the PM rising tide on March, 02, Richborough March, 02, 2001 TimeHeight 10: :26 2.9