Flutterby™! : Huh

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2011-02-28 23:26:05.619487+00 by Dan Lyke 9 comments

Huh: Not only are passenger jets more efficient per passenger mile than cars, the % of that cost spent on fuel is less. Despite the speed.

comments in descending chronological order (reverse):

#Comment Re: made: 2011-03-03 02:38:38.163207+00 by: jeff

Dan, +1 on the vehicle costs. And also for the route suggestion. We may try that route (or a variant) either on the way there or back.

That's why depending on what kind of deal we can get we'll likely rent a car. I don't have my flying car license yet. :)

Despite its overall inefficiences the car remains the vehicle of choice for many applications due to its flexibility. Air, rail, and other modes of mass transit rely mostly on fixed routes and choices among them are finite.

#Comment Re: made: 2011-03-03 00:17:58.018708+00 by: Dan Lyke

Jeff, know that your $3.75/gallon is roughly 20% of your vehicle's per-mile cost, the rest is hidden behind depreciation and tire changes and such. And why all the way over to Philadelphia. I'd take 71 up to 90, and across the New York Thruway. Colors all the way.

papa0so, if I've got someone for company (and to manage the munchies supply), driving is way more comfortable than flying.

Actual real flying cars:

You live in the future. If you want a flying car that badly, buy one. For me, wheels and friction seem to be the most generally applicable transportation mechanism.

#Comment Re: made: 2011-03-02 20:35:50.654475+00 by: papa0so

Yeah, I find it to be more economical to fly when traveling solo large distances (over 500 miles). However, if I am traveling with 2+ people, driving tends to be the way to go, despite how uncomfortable it can get.

BTW, they already have a flying car out - Google "the transition" :D

#Comment Re: made: 2011-03-02 00:23:05.763741+00 by: jeff

Debby and I are planning a New England vacation this fall at or near the height of the foliage season (probably the 2nd week in October).

We live in Columbus, Ohio. For various reasons our jumping off point may be Philadelphia. We're debating whether to use one of our cars to drive the entire trip, whether to rent a car to drive the entire trip, or whether to fly to Philadelphia and rent a car there.

If we drive the entire trip, we're conservatively projecting the following:

2500 miles 25 miles/gallon 100 gallons $3.75/gallon $375 fuel cost

Flying to Philadelphia would shave roughly 1000 miles from the overall driving.

Given the number and frequency of our stops multiple modes of transportation is seen as huge plus.

Eric--we need your flying car!

#Comment Re: made: 2011-03-01 18:02:44.903128+00 by: Dan Lyke

Eric: Very cool!

Dexev, digging a bit more into those numbers, my bits of a thread over on Facebook:

I'll probably have to put together more precise numbers, but there is one fudging in that: You have to come up with a reasonable number for passengers in the type of driving you're trying to compare.

For automobiles, costs are roughly 20% of fuel and run about $.55 per mile. See http://www.bts.gov/publication...statistics/html/table_03_14.html

This is a little outdated, but suggests that for a 747 operating costs are $2.6k/hr for fuel, $4.1k for other costs, ground costs are between 1.7 to 2.5x flying hour costs, 2.5 says fuel costs are 15% of operating costs. If you figure 300 out of 366 seats full, 82% capacity, and 500MPH (which is probably low, but we're fudging high on other places), that's less than twelve cents per passenger mile. A quarter of a single occupant automobile's operating cost. http://askville.amazon.com/cost-airline-fly-commercial-jet- York-Los-Angeles/AnswerViewer.do?requestId=2593308

To be fair, if we go back to 2003 in the BTS stats, an automobile wasn't much cheaper than today, $.517 per mile, but most of that difference is that fuel is way more expensive now than it was today, so, yes, at that time fuel costs were 13.9% of that cost, or on par with what fuel was as a percent of 747 operating costs.

And as a result of poking around like this, I had no idea that private jet prices are as cheap as they are (if you can commit to buying a couple of hundred hours a year).

Oh, and to Chris's point, one of my thinkings about the reason public transit doesn't work is that unless you're willing to work on its schedule, or can use it as usable time, fuel would have to cost 10x what it does now to make it reasonable for anyone who's regularly employed even at the lowest level and can afford a car. The reason city dwellers find it reasonable to get along without a car isn't the energy cost, it's the parking cost (both for storage, and for destinations).

In response to "shorter flights are less efficient":

Which is probably why there's such a huge (1.7 to 2.5) in that non-flight operating expense.

And I think 1.57 is the generally accepted reasonable number for passengers per automobile in the US, so if we compare 2003 numbers that'd be $.33 per passenger mile for automobiles vs $.08 to $.12 for a 747 per passenger mile.

(This is, of course, ignoring government subsidies of roads and airports...)

I should've done some more back-of-the-envelope calculations, although it makes sense, you can fly three thousand miles for $400 no problem, but what's more interesting about this is it says that if the social climate and need works around it, then you should be able to move people on high speed rail at a pittance per passenger mile despite the speed.

Not that I really have any hope of that, 'cause rail has always been primarily a mechanism for moving government funds into private bank accounts...

And, it also kind of corroborates some of Brad Templeton's BTUs per passenger mile numbers: http://ideas.4brad.com/green-u-s-transit-whopping-myth

On high speed rail, Cam suggested that a 300mph high-speed train from NYC to Chicago would make these numbers look huge.

Yeah, it depends on how many stops it has. California's proposed LA ->Burbank ->San Fernando ->Palmdale ->Bakersfield ->... well, at that point it's not clear if it'll go up to Sacramento and we'll be back to the Bay Area, or stop-and-go up the peninsula to SF, and it'll probably be faster, even with arriving at the airport an hour early, to fly.

Of course it could be quite a bit cheaper to take the train, but then the question arises: If it costs half as much to go to LA for the weekend, is the macro result going to be lower carbon emissions? Not clear...

If we manage to get that train running off of non-carbon emitting energy sources, then, yeah, it'll be a serious win, but we'll see how that goes.

But to the larger take-away: On safety, economy, or carbon emissions, and you'd take the trip anyway, flying beats driving, unless you've got about 4 people in the car for short trips, or 6 people in the car for longer trips.

#Comment Re: made: 2011-03-01 07:29:34.946071+00 by: dexev

I wonder how those numbers compare when you adjust for % occupancy. I haven't been on an airplane with more than one or two empty seats in a while. Meanwhile, 9/10 cars have four or five seats empty.

#Comment Re: made: 2011-03-01 05:45:10.229274+00 by: ebradway

Along those lines, Ed Parsons mentioned the world's shortest commercial air route: 3 miles! So there's an example of air transportation used on the scale of a local trip to the grocery store, much less a commute to work!

#Comment Re: made: 2011-03-01 03:43:42.099962+00 by: Dan Lyke

Good question. I'm working on that.

#Comment Re: made: 2011-03-01 00:56:28.256798+00 by: ebradway

So if planes are more efficient than cars. And cars are more efficient than public transportation. Why can't the government subsidize a flying car for me?