Real Navigation with SH4 - Page 2

06-30-07, 06:59 AM

Don - i need some help with the math part.

I have sailed from Pearl Harbor (docked) towords west for a patrol in the East China Sea.

I have crossed the dateline and are aproximately at 162° E going 9 kts on course 270°true.

Polaris was fixed at 08:09:33 to 27°45' Setting me at aprox 28°N

Sun Rise occured at 08:41:33 (RedLight off)
Almanac shows expected SunRise on the date at 28°N (extrapolated) to 06:27:00

Now.....

Im at Time zone L and calculating my BaseTime SunRise as below:
BaseTime.......GMT......Local Lima Time
08:41:45 ~ 19:41:45 ~ 06:41:45

difference in SunRise
.06:41:45
-06:27:00
------------
......14m45s converted to arc

..3°30' (The minutes converted)
+0°11'15'' (The seconds converted)
-----------
3°41'15''

that i deduct from the center of timezone Lima (165° E) getting a Longitude of

161°18'45'' E

Now CTRL+LMouse says 162°10'45'' E some 56nm from the calculated SR longitude

Arc difference is 0°52'0'' - nearly 4 minutes.

All the time im getting these 4 minutes of difference......!!!! WTF is that. Im suspecting that PEARL HARBOR TIME is offset somehow. PEARL is located at 157°57'30'' W And i wonder if that has anything to do with the spawning time..

06-30-07, 06:59 AM	#1
Mav87th Stowaway Posts: n/a Downloads: Uploads:	Don - i need some help with the math part. I have sailed from Pearl Harbor (docked) towords west for a patrol in the East China Sea. I have crossed the dateline and are aproximately at 162° E going 9 kts on course 270°true. Polaris was fixed at 08:09:33 to 27°45' Setting me at aprox 28°N Sun Rise occured at 08:41:33 (RedLight off) Almanac shows expected SunRise on the date at 28°N (extrapolated) to 06:27:00 Now..... Im at Time zone L and calculating my BaseTime SunRise as below: BaseTime.......GMT......Local Lima Time 08:41:45 ~ 19:41:45 ~ 06:41:45 difference in SunRise .06:41:45 -06:27:00 ------------ ......14m45s converted to arc ..3°30' (The minutes converted) +0°11'15'' (The seconds converted) ----------- 3°41'15'' that i deduct from the center of timezone Lima (165° E) getting a Longitude of 161°18'45'' E Now CTRL+LMouse says 162°10'45'' E some 56nm from the calculated SR longitude Arc difference is 0°52'0'' - nearly 4 minutes. All the time im getting these 4 minutes of difference......!!!! WTF is that. Im suspecting that PEARL HARBOR TIME is offset somehow. PEARL is located at 157°57'30'' W And i wonder if that has anything to do with the spawning time..