United Airlines Tries Hypermiling a Boeing | Hacker News Reader

United Airlines Tries Hypermiling a Boeing

wired.com

29 pointsyumraj16 comments

Bad show Wired. 1400 pounds of fuel… out of how many? What is the typical variation in transoceanic flights? Is this noise?

First it's 1,400 gallons

Second, about 6-7% (Extremely rough estimate)

Calculation:

Boeing 777 data: (nmi = Nautical Miles)

    Model      Fuel           Range      nmi/g
    777-200    31,000 US gal  5,240 nmi  0.17
    777-200ER  45,220 US gal  7,725 nmi  0.17
    777-200LR  47,890 US gal  9,380 nmi  0.20

(1,400 gallons * nmi/g)

Which means 238 to 280 nautical miles on a flight that is 3,772 nautical miles long. Which is a difference of 6-7%

Data from

- http://en.wikipedia.org/wiki/Boeing_777

- http://www.travelmath.com/flight-distance/from/Chicago,+IL/t...

Thank you for fixing both Wired's article and my units!

I still wonder about the variation due to weather though. I can say that flight times vary by at least 7%, so that would suggest that fuel use variation should also be over 7%.

> I can say that flight times vary by at least 7%, so that would suggest that fuel use variation should also be over 7%.

Couple of things to remember.

1. This was a single test flight. Not statistically significant by any measure.

2. My calculation was back of the envelope with unreliable figures. :)

I never heard the term "hypermiling" until this article. Did anyone else find it term cryptic and misleading? I envisioned windmilling the engines by setting them to idle or something alike.

"hypermilling" comes from hybrid car enthusiasts who try to max out mileage from their hybrid cars, most commonly Prius.

Now it is used for all sorts of cars. Look at http://en.wikipedia.org/wiki/Hypermiling for more info.

In fact per the above Wiki article, "In 2008, the word hypermiling was selected as the best new word of the year by New Oxford American Dictionary."

Looking at the Word of the Year finalists (http://money.cnn.com/2008/11/11/news/economy/wordof_year/ind...), they are sort of lame - Frugalista, Moofer, Topless meeting. Definitely questions the credibility of New Oxford American Dictionary.

I'm familiar with the term, but I'm used to it being used to describe really extreme improvements in mileage (like, getting 60mpg in a car rated at 27.)

In this case, they saved 1400 gallons on a round-trip transatlantic flight -- out of about 40,000 that would normally be burned on such a flight. 3% fuel savings is a big deal, but I wouldn't call it "hypermiling".

I've always interpreted hypermiling as "optimizing fuel usage to the furthest extent possible". Considering the #1 priority in designing airliners is aerodynamic efficiency/fuel usage/CASM, an ~8% decrease in fuel usage is absolutely nothing to sneeze at.

To put this another way, if Boeing could refine this technique and make it an approved operating mode for the 777 they would probably be able to book enough additional orders to add a billion dollars or two to the bottom line. The same could probably be said of any airline that could apply these techniques to all of its planes/routes. For an airline, improving fuel efficiency is the quickest route to increased profits.

I read it as "hypermilling", and I thought United was trying to mill a 777. Out of what, I wasn't sure. :)

Wood of course. They are breeding giant mutant trees.

Even without prior reference, it's a combination of a commonly used greek root "hyper", for "over, in excess, or more" with the word "mile". Its meaning can reasonably be derived from that.

Every occupation has it's jargon.

"Hypermiling" comes from a hobby, not an occupation. See yumraj's post.

Doesn't make it any less lame.

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