## Thursday, April 30, 2009

### You Do The Math - Planes and their carbon footprint

Some people warn you not to fly because of all the carbon dioxide planes emit and the global warming it causes. But, what they don't know is how fuel efficient airliners really are. Let's pretend for a minute that releasing all that CO2 into the stratosphere is not a bad thing, and simply go with your best way to travel while using the least fuel.

The Air Transport Association of America (ATAA) has just the numbers we need, so that today, You Do The Math!

Below, the first two columns of numbers are speed and gallons per hour of fuel consumed. If you divide one by the other, you'll get miles per gallon. Compare this to your family car. The most fuel efficient airliner is the Airbus A321, which only goes two-thirds of a mile for each gallon burned.

However, because it carries 169 passengers, multiply two-thirds by 169, and you get 114. Therefore, the plane can achieve 114 miles per gallon per person. This plane full of 169 people is the same as 169 people each driving their own car, each car getting 114 miles per gallon.

The latest information from the ATAA for 2007 showed that the average airliner in the U.S. flew at 79.9% seating capacity. Unfortunately, this means we have to multiply 114 by .799, and this increases fuel consumption per person to 91 miles per gallon. Still, that's a lot better than what you get any place else, except for trains (according to some European tree huggers).

So you have to consider how you would travel without airplanes. If you would put your 4 person family in a 22 mpg mini van, that comes out to 88 miles per gallon per person. Almost as good as the Airbus, and better than most other planes. If you travel alone in a Prius, you'll only go about 45 miles per gallon. You and your spouse on a 50 mpg motorcycle achieves 100 mpg per person. A family of four in a 30 mpg car goes 120 miles per gallon per person. It's hard to beat that.

However I know big families that have crammed 8 to 13 people in a van or suv, thus achieving between 100 and 200 miles per gallon per person. If you want bragging rights, that's the way to go. But it defeats the purpose. You must have 6 to 12 kids and then drive a 12 to 15 mpg tank, thus using more gas than other families.

Below we see 32 passenger planes (and 6 cargo planes) listed in the 2009 World Almanac with their 2003 ATAA statistics. Miles per gallon per person is the last column on the right. It doesn't really matter which plane you fly, they all get much better than the US average for cars and light trucks, about 20 miles per gallon.

But, see if you can score one of these top 13 airliners that all get over 62 miles per gallon per person. That way you can be snobbish to anyone who drives a Toyota Prius or Honda Insight.

Airbus A321, A320, A330, and A319
Boeing B757-300, B737-900/900, B737-400, B757-200, B737-700LR, and B767-400
Shorts SD 340B
McDonnell-Douglas MD-90
Lockheed L-1011

Airliner................speed......fuel......fuel............total......percent....miles per
..........................mph........used.....efficiency....seat......seats.......gallon
..........................gph.........mpg.......................filled.................... per person
B747-200/300......520.........3625....0.143..........370......79.9.........42.4
B747-400............534.........3411....0.157..........367......79.9.........45.9
B747-100............503.........1762....0.285..............0......79.9.............0
B747-F................506.........3593....0.141..............0......79.9.............0
L-1011................494.........1981....0.249..........325......79.9.........64.7
DC-10................497.........2405....0.207..........286......79.9.........47.2
B767-400 495 1711 0.289 265 79.9 61.2
B-777 525 2165 0.243 263 79.9 50.9
A330 509 1407 0.362 261 79.9 75.4
MD-11 515 2473 0.208 261 79.9 43.4
A300-600 460 1638 0.281 235 79.9 52.7
B757-300 472 985 0.479 235 79.9 89.9
B767-300ER 497 1579 0.315 207 79.9 52.1
DC-8 437 1712 0.255 0 79.9 0
B757-200 464 1045 0.444 181 79.9 64.2
B767-200ER 487 1404 0.347 175 79.9 48.5
A321 454 673 0.675 169 79.9 91.1
B737-900/900 454 770 0.589 151 79.9 71.1
MD-90 446 825 0.541 150 79.9 64.9
B727-200 430 1289 0.334 148 79.9 39.4
B727-100 417 989 0.422 0 79.9 0
A320 454 767 0.592 146 79.9 69.0
B737-400 409 703 0.582 141 79.9 65.5
MD-80 432 953 0.453 134 79.9 48.5
B737-700LR 441 740 0.596 132 79.9 62.8
B737-300/700 403 723 0.557 132 79.9 58.9
A319 442 666 0.664 122 79.9 64.7
A310-200 455 1561 0.291 0 79.9 0
B737-100/200 396 824 0.482 119 79.9 45.7
B717-200 339 573 0.591 112 79.9 52.9
B737-500 407 756 0.538 110 79.9 47.3
DC-9 387 826 0.469 101 79.9 37.8
F-100 398 662 0.601 87 79.9 41.8
B737-200C 387 924 0.419 55 79.9 18.4
ERJ-145 360 280 1.286 50 79.9 51.4
CRJ-145 397 369 1.076 49 79.9 42.1
ERJ-135 357 267 1.337 37 79.9 39.5
SD 340B 230 84 2.738 33 79.9 72.2