Comment by marvin | Hacker News Reader

Comment by marvin | Hacker News Reader

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We don't really need to make airplanes that use other energy sources than petroleum, if it could be manufactured or acquired at decent cost. If it should happen that we can't, we're hosed - moving through the air at 800kph is a dream unless you've got something approaching the energy density of oil. Hydrogen could be made workable, I believe - energy density per volume is something in the region of 30% of gasoline when compressed. With radical airframe changes, we might be able to uphold the status quo.

We have a long way to go considering the efficiency of the airframes themselves. Fuel consumption could be reduced drastically if we could go a bit slower, or there would be some radical design change (think sailplanes). Most widebody airframes today look like flying buffalos, with the resulting air resistance.

Almost all air transport of people happens on the border of the transsonic regime, where air resistance is a lot higher than it could be. Reduce speed with 30%, and you'll reduce the total energy consumption by a considerable amount. One can only guess how customers would take this.

Market forces today don't look like they are convective to such change, but one can always hope that some startup is able to eat a big piece of the pie. Personally, I am very enthusiastic about companies like http://www.dayjet.com/, who specialize in slightly-expensive but pretty-painless transport.

Sadly, aviation is one of the most ass-backwards industries in the world, burdened by the largest amount of politics, subsidies, bureaucracy and regulation I've ever seen. There are definitely huge business opportunities here, but there are mountains and mountains of shit to wade through before we reach them. I believe that better personal air transport would be the way to go - better and cheaper GA airplanes. The competition and politics here are still in the world class, but not quite as cutthroat as among the airlines. And the capital requirements are survivable, and the existing airplanes are even more ass-backwards.

It says something about an area of business when the military has been driving the bleeding edge for fifty years.

> Reduce speed with 30%, and you'll reduce the total energy consumption by a considerable amount.

This is one of the (few?) cases where government regulation is appropriate, one airline would go out of business but if every route changed there would be a month of griping and folks would get used to it.

The re-scheduling, route planning, change in maintenance schedules, etc would be a one time cost, but if that's true I can't imagine the airlines are not secretly hoping for something like that to give them some help.

No. There are many reasons why it isn't free to just fly the airplanes slower, all have to do with the opportunity cost of time.

If an airline now flies passengers 20,000,000 miles a day (100 flights x 200 passengers a plane x 1000 miles a flight) and needs 50 planes to do it, cutting the speed at which those planes fly in half will mean that the airlines need twice as many planes. The fixed costs on the planes are the same whether they are going 500Mph, 300Mph, or sitting on the ground, either way the company is still paying the lease or mortgage on the plane. Flight attendants and pilots have to be paid regardless of how fast the plane is moving.

Additionally, for passengers, arriving later isn't merely an annoyance to be endured, it will change decisions. People have alternative uses of their time, mechanics can't fix cars when they are in the air, doctors can't save lives. The (possible?) reduction in ticket cost wouldn't adequately compensate some people for the additional time that they lose. What your proposal just did was to take a private decision (for the airlines - how fast do I want to fly my planes, for the consumer - which ticket do I want to buy from a market of airlines that compete to get me there the fastest, cheapest, or some combination) and have taken that choice away by making a government mandate.

As a supporting data point here, one of the things which makes SWA such a profitable airline (in addition to its amazing luck using futures to hedge its fuel costs) is that it has some of the fastest turnaround times in the industry. Its planes spend their time flying, not on the ground waiting to be unloaded/loaded. This lets them get in more flights that other airlines with comparable fleets.

This is most definitely the first time I've ever heard anyone say the the problem with air travel today is too little government interference.

> This is one of the (few?) cases where government regulation is appropriate, one airline would go out of business

Huh? If it actually produces cost savings, folks who valued that cost savings more than time would flock to any airline that did it. If it doesn't, then why is govt regulation appropriate?

I doubt that minor changes in flight time matter to a lot of passengers, but since it's not my money at risk if I'm wrong, it's inappropriate for me to demand that others try.

If you think that you can run an airline better, do it. If you're right, you'll get rich and force existing airlines to either change or die. However, if you're not willing to risk your money, why should someone else be forced to risk theirs?

You can run a turbine engine on ethanol. It's just that the existing ones aren't certified for it.

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