Tuesday, February 19, 2013

Re: [Electric Boats] Measuring boat water speed for low speed & cost

 

Agreed.  You can probably get a cheap handheld GPS for around $100 - cheaper when they're discontinuing models.
For my power boat, I took the car gps and used that to check boat speed.
For slow speeds, it's probably better to use a handheld gps that's designed for hiking.

Be aware that the GPS will read total speed "over ground".   NOT your speed through the water.   That means you have to compensate for current and wind.
Generally speaking - this means running at the same power level over several different directions, and averaging the speed that you record.


From: Robert Lemke <robert-lemke@att.net>
To: electricboats@yahoogroups.com
Sent: Tuesday, February 19, 2013 2:26 PM
Subject: Re: [Electric Boats] Measuring boat water speed for low speed & cost

 
Handheld GPS.

--- On Tue, 2/19/13, Craig Carmichael <craig@saers.com> wrote:

From: Craig Carmichael <craig@saers.com>
Subject: [Electric Boats] Measuring boat water speed for low speed & cost
To: electricboats@yahoogroups.com
Date: Tuesday, February 19, 2013, 12:16 PM

In my e-outboard tests I couldn't measure the speed of the boat. I
bought a pitot tube, but the speedometer I found for it goes from
0-60 MPH and the first marking is at 10 MPH. The next one is at 15.
(From 40 to 60 each MPH is widely spaced - exactly the opposite of
what's needed.)

Blowing into the pitot tube, it takes all the pressure I can make to
move the needle just a little.

There must be some more sensitive transducer that can be used with a
pitot tube? Or is there some other way to measure speed that doesn't
cost a lot?

Cheers,
Craig

=====


------------------------------------

Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/electricboats/

<*> Your email settings:
    Individual Email | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/electricboats/join
    (Yahoo! ID required)

<*> To change settings via email:
    electricboats-digest@yahoogroups.com
    electricboats-fullfeatured@yahoogroups.com

<*> To unsubscribe from this group, send an email to:
    electricboats-unsubscribe@yahoogroups.com

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/



__._,_.___
Reply via web post Reply to sender Reply to group Start a New Topic Messages in this topic (4)
Recent Activity:
.

__,_._,___

No comments:

Post a Comment