Only getting 12mph!?!

Duane Dunn, Allegro · Post by **Duane Dunn, Allegro** » Fri Feb 16, 2007 8:54 am

No I meant it as I wrote it, your formula is written wrong, to use your numbers

1 Nautical Mile * 1.15 = 1 Statute Mile

17 knots * 1.15 = 19.55 mph

or as I wrote it,

19.55 mph = 17 knots * 1.15

I see nothing wrong with useing boating terms in a boating forum. If a new person owns a boat they need to learn the terms.

Every boat ownwer should have and read a copy of Chapmans. If they did there would be a lot fewer problems on the water.

Roger is wrong to use mph to pump up his marketing numbers.

Gotta go, time to hitch up the trailer!

eric3a · Post by **eric3a** » Fri Feb 16, 2007 10:55 am

daver360 · Post by **daver360** » Fri Feb 16, 2007 12:45 pm

I was talking about mph off the gps. But I'll take 15 mph anyday then what I was doing before. I still have yet to try the new prop though. 11 3/4X 12. Ive also been taking everything out of the boat I can to make it lighter. I still think from whatIve been reading that the Tohatsu is a better performer then the df50. I think If I have a major problem with the suzuki Ill be looking at an etec 75 or 90. The etec guys have me pretty much sold.

beene · Post by **beene** » Fri Feb 16, 2007 1:21 pm

Duane Dunn, Allegro wrote:No I meant it as I wrote it, your formula is written wrong, to use your numbers

1 Nautical Mile * 1.15 = 1 Statute Mile

1 nm * 1.15 does not equal 1 sm, it equals MORE than 1 sm as it is supposed to.

How does 1nm x 1.15 = 1sm when Nautical miles are longer than Statute Miles?

That is why I said 1 nm = 1.152 sm and I wrote no formula at all. Your formula 17 knots * 1.15 = 19.55 mph is completely correct!

Anyway's, hope you had a great day on the water, I am soooo jealous.
I hope your testing goes well

James V · Post by **James V** » Fri Feb 16, 2007 11:21 pm

My GPS has both so I use MPH just to make it easy on myself. Also I can have distance in Miles or Nautical miles. Usually, at only 15% differance is is no big deal.

However, it would be great if people would put down what they are using beside all numbers.

nchogberg · Post by **nchogberg** » Sat Feb 17, 2007 6:18 am

Gee Eric,

Your right! I guess I'll sell my boat and go back to driving my car. Come to think of it, all the times I used my "useless" handheld gps (in MPH) and my charts to navigate the Atlantic along the Fl. Keys must have been a dream. (I still cant figure out how I have pictures of our overnight anchorages, or of the snorkleing at Carys Fort lighthouse, must be a conspiracy!)

All the fun I had having my boys pinpoint our lat & lon on the charts by using our "useless" handheld gps (in MPH) must have been useless. Thanx for the wake up call. I suppose we could have ended up in Cuba OR worse BAYTOWN, TX!!!

Yep, I'll never be as superior as you, Eric, so why try, I'll just stick to the road where I'll never get lost using my "useless" handheld gps (in MPH) and leave the serious sailing to you!

Hmmm...now how do I find mapquest, I need to pick up some milk and I dont want to get lost going to the corner store. That Eric, so smart, what an old salt. I'm gonna miss that boat....

later...
Hawg

beene · Post by **beene** » Sat Feb 17, 2007 7:21 am

ouch

I don't think Eric meant it quite soooo well, um, poignantly.

eric3a · Post by **eric3a** » Sat Feb 17, 2007 8:31 am

Night Sailor · Post by **Night Sailor** » Sat Feb 17, 2007 4:06 pm

Eric,
Knots are to be preferred when using nautical charts to navigate offshores, coastal and great lakes or big rivers where such charts are made. Thousands of us however are lucky to even have old topo maps of our sailing waters to use for navigation. Such land area maps are in stature miles. Therefore, some of us have our GPS set for miles.

And occasionally if a landlubber guest asks how fast does she go, mph makes sense to them, whereas knots is so much gobbledy gook.

Many of us landlocked folks also use pocket GPS that we transport between car, rv, bike or backpack to go on the boat. Why change at all if all our uses are in stature miles.

eric3a · Post by **eric3a** » Sat Feb 17, 2007 5:58 pm

Highlander · Post by **Highlander** » Fri Feb 23, 2007 12:11 pm

I have the DF40 2000yr on my

& I run a 11 5/8 x 12 prop and she buzzes along quite nicely I just installed a tach in the fall so in the spring I'll see what RPM'S she running at WOT . This is a new prop same size as the old one but I want to check out the rpm range before I decide what I'll buy for a spare , the original prop center shock bushing gave out on me a yr ago in the middle of lake Simco on a 4 day cruise around the lake on the first day was able to get into Barrie at half throttle . And ordered a new prop took about 3 days

& it was going to take a week to rebush the old prop plus $50. more than the price of a new one

. So I'll be ordering a new spare prop some time this summer don't want to get caught on a cruise again like that can be a PITA

. Course if I'm on L. Simco I could always get a tow from "Beene" with his Merc 75 I shure would save on gas then

John

beene · Post by **beene** » Fri Feb 23, 2007 4:14 pm

Now that would be a sight

Gemini · Post by **Gemini** » Mon Mar 12, 2007 7:13 pm

I use SM when on lakes. Knots are a must when on coastal waters, navigable rivers and the Great Lakes. That is the rule I use.

baldbaby2000 · Post by **baldbaby2000** » Mon Mar 12, 2007 8:19 pm

1 knot = 1.15078030303 mph to be a little more precise.

Sorry, I'm in a wise guy mood tonight!

Seriously, I've gotten about 12 or 13 mph with my 40hp Tohatsu.

Lovekamp · Post by **Lovekamp** » Tue Mar 13, 2007 3:10 pm

eric3a wrote:Is there even a Statute mile scale on nautical charts?

Actually, those of us in the Midwest tend to use statute miles most of the time. Rivers are measured that way, and it tends to be more convenient on small inland lakes, as well. Even charts of the Great Lakes have a statute mile scale (along with meters, yards, and feet), but they don't have a nautical mile scale other than lines of latitude along the side.

MacGregorSailors.com

MacGregorSailors.com

Only getting 12mph!?!

speed