3 cents

Canadian airline Jazz Air thinks the answer to that question must be less than 3 cents. The airline recently announced that they were removing life vests from their airplanes in order to save on fuel costs. They can get away with using seat cushions as flotation devices since their flights mostly stay within 50 miles of the shore.

How much will this move save them on fuel costs? The life vests weigh about one pound apiece. I don’t know how long their average flight is. Let’s say it’s 1,000 miles. Using a fuel cost per pound to fly 1,000 miles of 3 cents, based on this online exchange, and then removing the life vests saves the airline 3 cents per seat per flight — not exactly big money.

Steven D. Levitt

4 thoughts on “3 cents”

  1. One suspects that the fuel savings is actually less, because some vacated space would be used for luggage.

    The primary savings, I suspect, would mostly be in time — explaining how to use the damned things is not easy and probably takes up 3-6 minutes per flight attendant per flight, plus some maintenance time to fix them. Regulations and the need to field counting numbers of flight attendants per trip probably means that there is also little saved labor costs, but time not spent explaining life jackets could make flights a few minutes shorter, and could free up time to sell movies and drinks.

    Honestly, the utility of life jackets is pretty low when seat floation is available, and maybe even a net negative.

    Crash landings are very rare and overwhelming take place immediately after or immediate before a planned takeoff or landing – not far at sea. Many crashes have no chance of survival due to an immediate breakup or explosion of the plane, or a near 100% chance of survival with little more harm than a bumpy landing. The vast majority of survivable crashes take place overland. Survivable water landings are even more rare (you can count the number of large commercial plane water landings in modern commercial air travel history on your fingers).

    Built in beacons, air traffic control systems, mayday calls, and air based search and rescue, usually mean rapid response times for rescuers. The difficulties associated with getting a life jacket functioning mean high misuse rates and time spent putting on life jackets may also slow evacuation rates that matter a lot. The most crucial survival factor in a prolonged survival after a water landing is water temperature, first, predatory water fauna (e.g. hungry sharks) second, and flotation device persistance even later.

    In short, I’m much more amibivalent than Levitt’s analysis would imply. There is a trival savings associated with a trival benefit, which is always a difficult to measure matter.

  2. In his original Levitt did say he’d take the 3¢ as being the better value (than the life jacket).

    Somewhere once I read there has never been a water landing by a commercial airliner. Never.

  3. I don’t think that the weight of an airline life vest is anywhere near one pound. Those things have air tanks and release mechanisms that add to the weight. I estimate that the actual weight of the flotation device is closer to four pounds.

    Not only that, they will also remove from the plane the mechanism that holds the life vest. That part is made of metal and weighs some twenty to twenty five pounds.

    So altogether the actual weight removed will be about twenty five pounds per seat.

    The mileage a plane gets depends on the type of plane, the number of engines, the burn rate, and the passenger weight.

    This site has many details about the problem that shows figures and graphs which can be used to calculate the number you’re looking for. It’s not as simple as one would hope.

  4. There have been five commercial water ditch landings (excluding couple of passenger flights) where life jackets could have been used in the plast 53 years. In one flight, on Ethiopia airlines, lifejackets cost many lives. In the others it is hard to tell.

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