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13 MPG is surprisingly good, I always thought it was much, much less.


Yeah, its like an SUV but twice as fast.


Perhaps 3-5x as fast in terms of time because you don't have to stop at red lights and you can take the "as the crow flies" path instead of zig-zagging. Pretty sweet deal for $30k!


Not really -- think "free like a puppy". Planes are like boats, except you die if you screw up. There are plenty of repairs, storage charges, etc that can get expensive pretty quickly.

General aviation is something you do out of love, not to save money.


> except you die if you screw up.

That happens with boats, too.

Perhaps not as often - boats don't fall out of the sky when they stop working - but it happens.


Planes don't really fall out of the sky either, especially modern commercial jets with high L/D ratios. There are some exceptions, e.g. fighter jets, but generally planes can glide down safely upon engine failure provided there is a nearby spot to land.

http://en.wikipedia.org/wiki/Lift-to-drag_ratio http://en.wikipedia.org/wiki/Lift-to-drag_ratio


We're talking general aviation here. Small private planes crash frequently.

I live around Albany, NY. In the past 18 months, there have been at least 4 fatal crashes that I can recall as a casual newspaper reader. Usually it's related to tired/inexperienced pilots combined with some other factor (mechanical, weather, etc).

One that I remember as a kid growing up in farm country was a guy who had an engine failure. Like you said, he didn't just fall out of the sky... he tried to glide into a field, and just missed it. Wing clipped a tree.


> Planes don't really fall out of the sky either

I did not intend that metaphor to be literal.


The death rate for yatch sailing is way below that of general aviation.

It's reported at 5.4 deaths per 100.000.

I've been involved in some ugly accidents myself as a crew member (a broken mast off the coast) and the only thing I got from that is an anecdote :) .

Unless you're in a mid-Atlantic crossing or caught in a storm, most screwups are recoverable. That's not to say you don't have to respect the sea - you definitely do.

http://www.uscgboating.org/statistics/accident_statistics.as...

sailing.about.com/od/navigationseamanship/a/Why-Sailors-Die-The-Most-Important-Safety-Lesson.htm


> The death rate for yatch sailing is way below that of general aviation.

Oh, sure. I'm personally aware of only one yacht casualty, and that was sudden and unexpected. The boat jibed while the fellow was standing, the boom swept across ...


True, but it takes around 45 minutes to prepare a plane for flight and about 20 minutes to put it away. Also, you have to drive to and from the airport. Planes are incredible, but you have to fly pretty far before they're a timesaver.


Where did those numbers come from? Preflight and run-up can be done in 20 minutes once you've done it many times and securing after a flight is as simple as turning everything off and pushing the plane in the hanger or parking on the pad. That's maybe 10 minutes at most.

The only really time consuming part would be making and filing a flight plan. If you've done the route multiple times, you already have the flight plan and if you're operating under VFR (visual flight rules), you don't need to open/close it.

Source: I'm currently a student pilot and have done this process many times.


My parents are both pilots. The numbers are just my estimates from having flown with them a bunch. Maybe my numbers are a little high, but I think I'd stand by them.

There's always a bunch of dealing with cranking open the hanger door with the winch, dragging the plane out, checking that there is no water in the fuel (both tanks), transferring the stuff you're bringing with you from the car to the plane, getting into the seatbelt, plugging in the headsets and checking that they're all working, talking to the tower, taxiing out to the runway, waiting for a plane or two to take off, and then actually taking off.

Anyway, have fun flying.


Alaska is one state with many pilots. Distant towns and the road conditions make it quite normal to fly.


I believe there's a town in California where everybody has their own hangar, instead of garage.


Breakaway Park Airport Community, near Austin, TX. (http://www.breakawayairport.net/).

I understand they get very cranky if you try to take off or land too close to sunrise or sunset.


and usually 30 min to drive to the airport.


avgas is more expensive doe


Yeah, where I am, it's about 5/3 as expensive. The upper bound improvement factor you can get over driving due to flying in a straight line is 2/sqrt(2), so your best case cost-equivalent efficiency is about 11 mpg.


The upper bound is infinite if you fly a route with no road equivalent, for example to an island. Even sticking to a single landmass, you can get arbitrarily high, as roads can be extremely indirect in some cases.


This is why I'm excited about electric airplanes and driverless cars. A GA electric airplane has about 1/10th the energy cost of an avgas one. The cost of avgas is what discourages me from owning an airplane.


In most cases, avgas will be under half your total expenses for the year. You have to fly well over the average utilization for gas to dominate over maintenance, insurance, hangar, database updates/charts, etc.

Even at 100 flight hours/year in a thirsty airplane, you'll spend maybe $10K on fuel. It would take a very simple airplane, hangared very cheaply, and no abnormal maintenance events for the year, for those other costs to be under $10K.

Few privately owned planes fly even 100 hours per year, and most of the non-fuel costs are largely fixed, meaning you pay them all just to fly the "first hour" and then subsequent hours just cost fuel and a small wear-related maintenance allocation.

Airplanes are cheap to buy, but not cheap to fly. The cost of gas hurts, but doesn't dominate in my experience (owning three airplanes over 15 years, and flying my family on most of our domestic travel east of the Mississippi).


You're not taking into account the vastly simpler design of an electric aircraft. An electrically propelled aircraft will have maintenance requirements similar to a glider. Fewer engine overhauls and much simpler procedures means significantly reduced cost.


I don't think you're taking into account the vastly increased battery maintenance, inspection and capacity testing that will be required.

Yes, you'll save a lot on not maintaining a piston IC engine.

You'll give some of that back in inspection processes to ensure that you don't have 95% of the range that you think you have. If you run of out power in a Leaf or a Tesla, it's overwhelmingly likely that the car will come to rest on a piece of pavement and intact. If you run out of juice in an electric airplane, you turn into a glider, and it's far from assured that you'll end up at an airport or on pavement.

I'm not scare-mongering, but that's the point of view the FAA will take on inspection and testing requirements for electric storage systems to achieve equivalent level of safety.

I know when I add 40 gallons into my left tank (beyond the unusable fuel) that I have added 40 gallons of range. I need some similar assurance for battery capacity. (again, it's not me, but the FAA.)

Just have a look at the annual inspection requirements for ELT and starting batteries for piston airplanes. And those are not propulsion systems. The batteries that run the AHRS in the G1000 and Aspen systems are also onerous and those batteries are crazy expensive relative to their capacity.

I can see electrics working for flight school airplanes, especially if they can get the 80% recharge time down under 2 hours.

I don't see them as practical for cross-country travel anytime soon without advances in battery tech; those are inevitable, but I don't see them displacing liquid organic fuels in my flying career for 1000nm legs.


I would think inspecting & maintaining the actual capacity of the battery would be part of the automated charging system. It would be recorded to a fine a amount of detail. Most airplanes have a more predictable energy consumption model than a typical consumer car also, and since the typical pilot is more sophisticated, can afford to show a more complicated energy display for more accurate energy consumption and range assumptions.

Electric aircraft currently would be very useful for people who live on an island or island cluster or want to do frequent short hop flights. For example Hawaii, the Caribbean, Indonesia, the Philippines, Seattle and the near by gulf islands, etc. I can take a ferry boat for 3 hours at scheduled times or I can hop on my plane for 30 minutes at any practical time at the same cost really changes things for island dwellers. I could live on an island and theoretically commute to work every day for 45minutes of total travel time. Going to Tahoe every weekend wont be a big deal, etc.

It would be also useful for future automated air taxis, since the energy costs would soon dwarf the cost of everything else in those situations.


If it were my ass up in the air, I think I would prefer that the electric power to the drive motor(s) be provided by a very reliable Diesel-cycle or external combustion generator and not just a battery pack, at least with our current generation of battery technologies. #2 fuel oil is far more energy-dense than any battery that I can afford.


Agreed. Aviation diesels typically burn Jet-A (widely available at airports, obviously) which is similar in energy content to #2 (and about 50x the energy content of Li-ion batteries on a J/g basis).


As far as I know, the major difference between Jet-A and #2 is that is has a much lower gel point than even the northern winter diesel fuels, because higher = colder. If you already have electric motors, wouldn't electrically heated fuel tanks suddenly be more possible than trying to divert waste heat out of fuel-burning engines?

You could save a LOT of money on fuel if you could use off-road #2 oil instead of Jet-A.


Dry adiabatic lapse rate is approximately 3C per 1000'. I regularly fly at high VFR altitudes or low flight levels in my private (gas, piston IC) airplane.

Even confining yourself to 15K feet, you'd be ~45C or 81F lower than the sea-level temp (assuming the air was totally dry, so maybe call it 35C or 63*F). The wings are extremely effective radiators, and wet wing tanks have fuel right against the outer wing surface.

So, you're going to need to dump an enormous amount of energy into the fuel to keep it heated and non-gelled, which is why we have Jet-A, and in fact many jets need to add Prist anti-icing agent, and even some high-flying piston engine airplanes run their avgas through oil-to-fuel heat exchangers.

So, even if you're going to fly your diesel engine (or diesel generator) airplane in the mid-teens, you're probably still going to want to use Jet-A, both for its superior anti-gel properties but also because of the supply chain dedicated to getting Jet-A to a great many airports where you'd want to operate from.


Well, I used to drive my Land Rover LR3 4.4 V8 on the german autobahn regularly and I would say 13MPG is exactly what I was getting while cruising at 120mph.


US or UK MPG?


UK gallons.


More like a sports car that takes ultra premium as the plane can't carry a lot of people, can't tow anything and generally can't fly in bad weather.


And 1/10th the capacity!


There are plenty of small aircraft that get 30-40mpg cruising at ~150mph. They are usually home built.




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