GPS format

[NAUTI-NOTIONS]

which is better?

D.M.S
OR
DM.MM
I see both out there and just unclear if one is better or preferred
Sam

[Pilar]

CG uses D M.MMM. Most paper charts are D M S or Loran. You can drop the third place on the fractional minutes and get close enough to see the boat that hailed you in.

When talking to the CG you would state your position IE: N44d 59.000' by W124d 35.003' as "North Forty four degrees, Fifty nine Decimal zero zero zero minutes by West One twenty four degrees, Thirty five decimal zero zero three minutes." Get a repeat back when reporting your position for rescue and you will know for sure that they know for sure where you are at.

D degrees
M Minutes
S Seconds
.MMM thousandths of minutes

I don't know if there is any advantage of one system over the other. The only factor I can think of is the DMS format of most paper charts. Conversion can confuse you. To go from seconds to .MMM just divide seconds by 60 and round to 3 places. IE 58 seconds becomes 0.966 minutes. to go the other way multiply the fractional minutes by 60 to get seconds.

Aren't you glad they have not imposed the metric system on Navigation?

[NAUTI-NOTIONS]

call me confused
my unit dosen't have just plain old D M S
my choices are
hddd.ddddd
hddd mm'ss.s
hdd mm.mmm
along with a wide varity of international formats
all my waypoints are d m s (n 48 28 04 w 124 56 44)
which should i select to get closest to that format?

[Sensei-san]

hdd mm.mmm I assume that h=heading as in N.E.W.S.

Pilar is correct. Always give you position in Latitude first and longitude second. A lot of people don't realize that is the correct way to give your position. Especially if you are shorthanding a position for a friend nearby.

Although decimalization has crept into Lat/Lon positions. The NOAA bouy page used to give the bouy positions in decimal form. I notice they have relented and now have the dd mm ss notation after their decimalization.

I agree with Pilar that decimalization or conversion to another notation form for lat/lon positions would be crazy. Practically every navigation course teaches you that a minute of latitude is a nautical mile. Because of this fact, it is easy to figure out your position relative to someone else if they use dd mm ss or dd mm.mmm format.

[ 03-04-2004, 06:51 PM: Message edited by: Sensei-san ]

[NAUTI-NOTIONS]

one more thing to have on board "calculator"
thanks
i think
Sam