GL: Hyper Mileing

[M S]

Now you are changing the rules on me. I was working from the assumption that you are traveling the loop and need to get from point A to point B and what is the most efficent means of doing so even if it takes a little longer.
   
  If the new assumption is how to get the most time on the water, mpg still is the way to go. Let's assume you want to be on the water for 8 hours. Travel at the most fuel effiecent speed (if you are fighting a current that may be a faster speed with higher gph but also higher mpg). If it looks like you are going to arrive at your destination before the 8 hours is up, anchor and take a swim or have lunch. The net effect is you still have 8 hours on the water and will have burnt less fuel. 
   
  Before we started the loop, we used to spend a lot of time at a nice anchorage about a mile from the marina. We'd get 10-12 hours of on the water time for less than a gallon. 
   
  As mentioned previously, if there is no current or the current is going your way, less throttle is more efficent (from either perspective). Once you start fighting a current, you need to account for it to determine efficency and it may or may not lead you to throttle up depending how much current there is and how fast your boat goes at different throttle settings.
   
  Mike & Tammy
  Valhalla II

Luther <captaincarrier at yahoo.com> wrote:
  "Since this has been a discussion of being more fuel effient," 

FWIW:

Well if I am using less fuel per hour, I am being more fuel efficent. Ones distance traveled will vary due to current, wind, bridges, etc which are unpredictible to a point, but do happen. If I (as I have in the past) schedule my trips with current direction and bridge openings I can maximize both speed and fuel economy. However, speed and distance traveled is not of the importance, it is the time on the water. That being said 'time on the water', then gallons per hours seems to be the preferred measurement.

Let's not forget, keeping your fuel clean and your tanks healthy can also improve your fuel economy. More than speed will come in to play while we try to reduce the rising cost.


Luther



--- On Tue, 6/24/08, M S wrote:

> From: M S 
> Subject: Re: GL: Hyper Mileing
> To: captaincarrier at yahoo.com, great-loop at lists.samurai.com
> Date: Tuesday, June 24, 2008, 8:58 AM
> Item 1: gph: Since this has been a discussion of being more
> fuel effient, gph doesn't take into account how far you
> are traveling per hour, so it doesn't tell you how
> efficent you are being with a current. With no current
> there is a direct correlation with mpg but that can get you
> into trouble if you don't realize the current is there. 
> 
> Example: At a particular throttle setting you are buring
> 1 gph and making 5 mph thru the watter. You have 20 miles
> to a safe port and 5 gallons left. Do you have enough fuel?
> If there is no current, you have a range of 25 miles, you
> should make it with a gallon to spare. Same senario
> fighting a 3 mph current. Since you are now only making 2
> mph over ground, you will come up 10 miles short (and
> possibly run out after dark). Gph doesn't provide
> useful info until you account for speed, which is what mpg
> gives you. 
> 
> ***************
> Another monkey wrench please, what would be the outcome
> if one were to figure gph rather than mpg? I never relate
> to mpg on the water even when the charts indicate such. For
> fuel consumption I find gph much safer.
> 
> Item 2: Huck Finn had a boat with infinite
> efficency (not exactly but close enough for our purposes).
> Zero gph. If you run the math, it is always more effient to
> slow down going with the current. The practicle limit is
> enough headway to maintian control. There might be a
> slight downtic in fuel efficency right around idle as
> internal engine friction becomes greater than the effort to
> turn the prop, but it should be pretty minimal.
> 
> ****************
> quander this.,... If you are going down current, are you
> better to go at a higher speed? 
> 
> See you on the Waterways!
> 
> Capt. Sterling
> 
> Mike & Tammy
> Valhalla II