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Mudraxus · 09-08-13, 04:09 AM

Hello Kameraden!

I downloaded the TDW mods, including Real nav a couple of days ago, and did quite some research on Nautical navigation. But I ran into two Problems.

Following Situation. I'm enroute from Helgoland to Scapa Flow. I have a rather accurate DR Fix (done by myself) and find myself around 55°48N' 3°46'E . One would expect that the sunset and rise is round about 16 minutes earlier on the GMT Clock than it's stated in the Almanach Table or the Shift-B Board. But the SH5 Reality is, that these events are happening over an hour after the times, putting me in the Atlantic instead of the North sea.

Second Problem, shooting Stars with the Sextant (The Red Vertical thingy) . I have a Free Sextant Calculation App for my android Phone, so I punched in three Stars, (Polaris, Mirach and Dubhe) and the App told me I was over 1000 nm SW of my Current Posit. At the same Time I was looking up the exact situation at Stellarium and I figured out that there seem to be Errors between 12 and 5° on the measurements in SH5.

So my question is, is it even possible to get a somewhat accurate Fix without the aid of the Navigator? Are those Angle errors real or do I just make some stupid mistake? And if there are errors how to Correct for them?

Thanks!

Ps. If you wanna try to calculate here are the numbers
DR: 55°48N' 3°46'E 8. Oct 1939 18:40
Polaris measured Angle: 49°50'
Mirach: 17°55'
Dubhe: 32°40'

09-08-13, 04:09 AM	#22
Mudraxus Nub Join Date: Sep 2013 Location: Germany Posts: 2 Downloads: 37 Uploads: 0	Hello Kameraden! I downloaded the TDW mods, including Real nav a couple of days ago, and did quite some research on Nautical navigation. But I ran into two Problems. Following Situation. I'm enroute from Helgoland to Scapa Flow. I have a rather accurate DR Fix (done by myself) and find myself around 55°48N' 3°46'E . One would expect that the sunset and rise is round about 16 minutes earlier on the GMT Clock than it's stated in the Almanach Table or the Shift-B Board. But the SH5 Reality is, that these events are happening over an hour after the times, putting me in the Atlantic instead of the North sea. Second Problem, shooting Stars with the Sextant (The Red Vertical thingy) . I have a Free Sextant Calculation App for my android Phone, so I punched in three Stars, (Polaris, Mirach and Dubhe) and the App told me I was over 1000 nm SW of my Current Posit. At the same Time I was looking up the exact situation at Stellarium and I figured out that there seem to be Errors between 12 and 5° on the measurements in SH5. So my question is, is it even possible to get a somewhat accurate Fix without the aid of the Navigator? Are those Angle errors real or do I just make some stupid mistake? And if there are errors how to Correct for them? Thanks! Ps. If you wanna try to calculate here are the numbers DR: 55°48N' 3°46'E 8. Oct 1939 18:40 Polaris measured Angle: 49°50' Mirach: 17°55' Dubhe: 32°40' Last edited by Mudraxus; 09-08-13 at 04:40 AM.