40 + MPG Air and Auto Vehicles

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jedi

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This is a new thread started as a result of the dreaded Thread Drift in "Hydrogen Use Storage and Transport" thread at post # 85.

Under the bumper of a Suburban in Dallas?

(FWIW, I agree, totally, BB. If I could find a good CRX I'd buy it immediately.)
I often picture how well my 40 mpg Honda Del Sol would fit under the 18 wheelers that I draft on occasion. In reality doing 75+ next to four of the xxx tires and wheels, parts of which are constantly displayed along the once upon a time "freeway" is a bigger concern.

This thread is activly looking for follow up comments on high mileage vehicles including the elusive "Roadable Aircraft" My solution for improving the mileage and safety of the high mileage road vehicle is to take to the air to avoid the heavy / light weight vehicle mix. By light weight I mean down to the bicycle on the roadways issues.
 

cluttonfred

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I am not quite sure where you're going with this, jedi. IMHO (which I have repeated here often enough), safe and practical roadable aircraft/flying cars are a pipe dream as long as you're surrounded by vehicles so much heavier than a light aircraft. A Van's RV-7, hardly a lightweight, has a typical flying weight of about 1700 lb. A base Honda Civic with a full tank of gas a couple of people onboard weighs double that, a Cadillac Escalade four times as much. They physics just don't add up for road safety vs. flight performance, you end up with a good-flying aircraft that's a death trap on the road, or safe car that's a dog in the air.

On the other hand, if you are willing to leave the plane at the airport and bring your ground transportation as cargo, then solutions are readily available right now. You can get a good (not great) folding electric bicycle with plenty of accessories (helmet, pump, tools, spare tubes, lights, etc.) for under $1500 and less than 100 lb all in. It's got a 45+ mile range, so you can go anywhere that's within 40 miles of a suitable airport, or hop in a bus or a rideshare service that allows bikes. For example....


Then take any efficient two-seater, preferably a tandem seater, and remove the passenger seat/belts/controls and replace with a cargo bin so you can throw stuff in there without worrying about blocking the stick or snagging a cable. Tweak the engine and aerodynamics for maximum cruise efficiency. For inspiration, study Klaus Savier....


There you go, 40+ mpg air/ground transportation problem solved. :p
 

Vigilant1

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In many (the majority of?) places, travelling on an electric bike means sharing the road with cars and trucks. From a safety perspective, that's not much of an improvement over even a flimsy roadable plane.

But, I agree that roadable aircraft are not practical. An observation of driver behavior in any parking lot or the number of folks texting while driving takes the shine off the idea, at least for me.
 

galapoola

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I think that all new roadbeds should always have a 5000’ grass runway included in their design every 75 miles or better.
Wasn’t that one of the goals of the Eisenhower Interstate System? To have straightaways strategically placed for military aircraft emergencies?
 

PMD

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I will go back to the original post and comment on the purely ground-bound. You can have a really nice car at far better than 40 US mpg. Well, you COULD - until VW got caught cheating and made out as the only bad guys. Their high point was a 3 litre Lupo (3 l. fuel/100 kms = about 80 something USmpg). I am quite comfortable with our now ancient Jetta wagon that gets in the high 40s (US) at near light plane speeds. My old Yankee would see an easy 20 USmpg all day and night, and my Tiger 16 at much, MUCH higher speeds. So, the 40 USmpg airplane has been a bit out of my reach for some time.

I think a REALLY clean design with a nice VW diesel flown at best l/d MIGHT be able to get there.

drive/fly machine? No way anything reasonable is ever going to meet that requirement.
 

Pilot-34

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Lol I think it was a 1981 Chevy Chevette I had that got 50 miles per gallon. One of the cheapest cars I think I’ve ever owned. And probably among the most reliable the only thing that kept it from having a perfect reliability record was when fueling well-meaning people and pump jockeys that would take the diesel pump hose out and replace it with a gasoline hose.
I suspect it would be even worse in an aircraft application!
 

cluttonfred

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You had a diesel Chevy Chevette?!? Not many people can say that.

Lol I think it was a 1981 Chevy Chevette I had that got 50 miles per gallon. One of the cheapest cars I think I’ve ever owned. And probably among the most reliable the only thing that kept it from having a perfect reliability record was when fueling well-meaning people and pump jockeys that would take the diesel pump hose out and replace it with a gasoline hose.
I suspect it would be even worse in an aircraft application!
 

Pilot-34

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They were a rare but good animal! I also had a Chevy diesel lLuv That got 35 miles per gallon. Both of these vehicles were the same and then the mileage never seemed to change, fast ,slow ,loaded or empty.
I once drove the pick up truck from the middle of Illinois to Slidell Louisiana all on interstate all at exactly 55 miles per hour and got exactly 35 miles per gallon.
At Slidell the seashell man loaded my pick up truck with every seashell it would hold in fact more because we were dribbling them over the edges on the way down the road. Not wanting to drive the grossly overloaded shell dribbling machine on the interstate I drove home on Highway 51 which has exactly 12,000,000 stoplights stop signs and traffic problems. Of course at each stoplight I would stomp the throttle to the floor and push it as hard as I could untill the next stoplight when I would smash the brakes and try to get stoped.
35 miles per gallon!
The one time the Chevette got more than 50 miles per gallon was coming across North Dakota in the summer with an 80 mile an hour tailwind wind. Of course the one time I got less when I turned around and went the other direction
 

jedi

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Isn’t there already a 2500 foot strip within 25 miles of every place?
Maybe in IL but not AK nor where I am. The grass strips I know of are 80% or more private and are getting more and more restrictive. They are not open to the general public.

The WA State equivalent are the state run airports originally for emergency and fire fighting use.

There are only 8 in the state.

Image result for wa state operated airports

WSDOT-Managed Airports
  • Bandera State Airport.
  • Copalis Beach State Airport.
  • Easton State Airport.
  • Lake Wenatchee State Airport.
  • Little Goose State Airport.
  • Lower Granite State Airport.
  • Lower Monumental State Airport.
  • Methow Valley State Airport.

1632495228154.jpeg
 

Dantilla

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Engineering a vehicle for both flying and road use is like designing footwear that performs as a running shoe and ski boot.
The compromises are too great to overcome. It will be lousy at both.
 
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Victor Bravo

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I came up with an idea to solve this problem years ago and posted it on this forum. My Nobel Prize has not yet been delivered, nor has my cover story in Scientific American, Popular Mechanics, or Time magazine. Ingrates...

Take a decent, more durable model of road bike. Weld (or bond) four or six attach tabs onto the frame. Modify a paramotor harness to include straps attaching the bike frame as well as the pilot. Rig up some sort of a basket or a rack to hold the folded canopy.

Starting in front of your house, you get on the bike with the power unit on your back, but the canopy folded in the basket. You ride your powered road bike to an open space or even the local airstrip.

Unfold the canopy, hook up the risers, get back on the bike, and take off as a paramotor with the pilot still sitting on the bike seat. Fly around at 30-40 mph as a paramotor, over to the next town. Chances are you will do so at a fairly respectable miles per gallon number.

Look down at the tragic, unwashed, pitiful souls honking their horns on a gridlocked freeway.

Land at your destination (on the bike wheels, no twisted ankles or knees blown out), fold up the canopy into the basket, and have the power unit on your back push your bike down the road in to town. When you get to your job, roll the bike and the power unit into the parking garage and run a cable bike lock through everything and walk in to your office.

No it's not an Escalade or a Ferrari, and no it's not a folding switchblade sleek Jetsons machine. But everything described above is COTS stuff you can buy now. No miracle batteries, no renderware, no venture capital. the FAA sees, accepts, and somewhat understands powered parachutes, far more than they accept or understand eVTOL. So you have a far far better chance of being able to test and demonstrate this compared to a solar/fracking/cosmic ray powered multi-copter.
 
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