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Old 07-11-2011, 03:12 AM   #100 (permalink)
bwilson4web
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Join Date: Mar 2009
Location: Huntsville, AL
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Quote:
Originally Posted by jamesqf View Post
Except that that's more than a little misleading: a 747 configured for max passenger capacity can get over 100 mpg, but it's hardly efficient for one passenger. Rail can do even better, 400-500 passenger-mpg, but again hardly efficient with one passenger.
I would be more impressed if you had bothered to post an example:

On the flight to Dallas/Fort Worth, I asked the flight crew on each leg how much fuel and how many seats. I used the Huntsville to Dallas distance via Google Maps for the distance and wall-clock time. So I was able to calculate my miles per gallon for the trip and the elapsed, net speed, including the plane change in Atlanta.

Where is your data?

I'm sorry but this is an especially weak, 'special pleadings' to make to someone who lives in Huntsville AL. We just had the latest 'airline closing our Huntsville operation' to our local airport. So every time I pay for my own flight, I find the best price from either Nashville, TN, two hours away, or Birmingham, AL, two hours away. I'm very much aware of load factors and the impact upon flight routes from direct, personal experience.

Quote:
Originally Posted by jamesqf View Post
I wonder, though, about the relative efficiency of Insight vs Prius. . . .
Excellent point, let's look at the respective specifications:
  • weight - 1,865 lbs vs 2,765 lbs
  • cross-section - (66.7 x 53.3) vs (66.7 x 57.6)
  • coefficient of drag - rear wheel well covers vs. nothing:


Lower weight is lower rolling resistance. Smaller cross-section is lower drag for the same coefficient of drag. Closer to laminar airfoil, lower drag for same cross section. As for vehicle drag, ask the owner of the Honda with a 0.10 coefficient of drag:


Quote:
Originally Posted by Frank Lee View Post
Not if you have 1 person + some stuff/vehicle cuz they're all going different places at different times.
Ok, based upon your specs, here is your next car:

Of course this is unfair but it shows the where this argument leads to.

In reality, I'm a great believer in "the right tool for the right job" but sometimes you get a tool a little larger to deal with outsized loads . . . like groceries or taking co-workers somewhere. But I also have co-workers who commute on motorcycle (except when it rains or icy or snow or too cold or too hot.)

Bob Wilson
__________________
2019 Tesla Model 3 Std. Range Plus - 215 mi EV
2017 BMW i3-REx - 106 mi EV, 88 mi mid-grade
Retired engineer, Huntsville, AL

Last edited by bwilson4web; 07-11-2011 at 07:56 AM.. Reason: found resized image for Franks dial-up
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