Let me first explain what the table is showing — Page 447, Lesson 421

I want to walk you through the sunrise table in your General Navigation book. This is a working tool, not just a page of numbers — it's the kind of table you'll actually use to plan a flight so you know when daylight begins at your departure, destination, or any point along your route. Let me first explain what the table is showing. The title is "SUNRISE." The columns across the top are dates — and look carefully, they run from May 17th, through June, into July 1st. So this particular page covers roughly the middle of May to the start of July. The rows down the left side are latitudes, labelled "Lat." in degrees. You'll see N 72, N 70, N 68, all the way down through N 60, N 50, N 30, N 20, N 10, then the Equator at 0, then into the Southern Hemisphere with S 10 and S 30. Now, the numbers in the body of the table — each one is a time, given in hours and minutes. So when you see something like "01 38," that's 1 hour 38 minutes. The key thing to understand is what these times actually represent. In this table, the time shown is the time of sunrise expressed in UTC — Universal Time Coordinated, the standard time reference used in aviation. So the table is telling you: at a given latitude, on a given date, the sun rises at this UTC time. Let me trace through a few entries so you can see the pattern. Look at latitude N 68, on May 17th — the entry is 01 38, so sunrise is at 01:38 UTC. Move across to May 20th, it's 01 20. May 23rd, 00 58. May 26th, 00 25. Then the entries become "G" — and that G is important. G stands for a period when the sun does not set — continuous daylight, the midnight sun. At N 68, from late May into early July, the sun never goes below the horizon, so there is no sunrise to record. That's why those cells are marked G. Now look at N 66. On May 17th, sunrise is 02 16. May 20th, 02 04. May 23rd, 01 52. May 26th, 01 39. May 29th, 01 27. June 1st, 01 14. June 4th, 01 01. June 7th, 00 47. June 10th, 00 31. Then from June 13th onward, it's G — continuous daylight again, but note it starts later at N 66 than at N 68. The higher the latitude, the earlier the midnight sun begins. Let me show you the shape of the whole table. At N 64, May 17th is 02 42, and the times decrease through the month, reaching a minimum around the solstice — you'll see values like 01 31, 01 32, 01 35, 01 40 — then they start increasing again. That's the key pattern: sunrise times get earlier as you approach midsummer, bottom out near the summer solstice, then begin getting later again. At N 62, May 17th is 03 02, and it follows the same curve. At N 60, May 17th is 03 19. As you move to lower latitudes, the variation across the season becomes smaller. Look at N 50 — May 17th is 04 12, and the values hover around 03 50 to 04 19. At N 30, May 17th is 04 55, and the range is narrow — roughly 04 45 to 04 55. At N 20, May 17th is 05 06, and it barely moves, staying around 04 58 to 05 06. At N 10, May 17th is 05 39, and it's almost flat — 05 38 to 05 43. At the Equator, 0 degrees, May 17th is 05 53, and the times drift very slowly — 05 53 up to 06 00 by July 1st. That makes sense: at the Equator, day length is nearly constant all year, so sunrise barely changes. Now cross into the Southern Hemisphere. At S 10, May 17th is 06 07, and the times get later as you move toward July — 06 07, 06 08, 06 09, 06 10, climbing to 06 17 by July 1st. At S 20, May 17th is 06 20, and it increases steadily. At S 30, May 17th is 06 39, and it climbs through 06 40, 06 42, 06 44, 06 46, 06 47 — and the excerpt cuts off there at 06 4-something. Notice the contrast: in the Southern Hemisphere, May to July is approaching winter, so sunrise is getting later, the exact opposite of the Northern Hemisphere trend. So here's the practical takeaway for you as a pilot. When you plan a flight, you use this table to find the UTC time of sunrise at your latitude and date. You then compare that against your planned time of arrival or departure. This matters because of operational rules — for example, if you're planning to arrive at an airport without instrument approach facilities, you need to arrive before sunset, or you need to be aware of the daylight available. The table gives you the sunrise half of that picture; a companion sunset table gives you the other half. One more thing to note about reading the table precisely. The latitudes are given in whole degrees, and the dates are given at intervals — 17th, 20th, 23rd, 26th, 29th, then every 3 days through June and July. If your exact position or date falls between two entries, you interpolate — you estimate the value between the two nearest entries. For a sunrise time, a linear interpolation between the two bracketing values is usually accurate enough for planning purposes. Also, be careful with the G entries. If you see G at your latitude and date, it means continuous daylight — there is no sunrise because the sun never sets. That's a significant operational consideration: you're operating in a period of 24-hour daylight, which changes how you think about rest, crew duty, and night operations. So to summarise what this table gives you: for any latitude from N 72 down to S 30, and any date from May 17th to July 1st, you can read the UTC time of sunrise, you can see where continuous daylight begins at high northern latitudes, and you can see the seasonal trend — earlier sunrise toward midsummer in the north, later sunrise approaching winter in the south. That's your sunrise planning tool.