This idea was first posted on Tuesday, October 31, 2006.

The technosuckers ought to love this one.

Many years ago, I was watching an auto race on the TV when the announcer made an interesting observation.  I don't remember what kind of cars were being raced.  There are a lot of different kinds.  However, the announcer observed that the aerodynamic design of the cars was such that, when they were moving at their intended maximum speed, then the aerodynamic downward force on the cars was larger than the weight of the car.  "Wow!" I thought.  "That means that they could run on the lower surface of an overhead road!"

That thought just naturally leads to the idea of a tubular highway.  I've shown a very simple schematic representation of one, in a cutaway axial view, in the sketch.  I've shown, very simply, most of the major features of such a tubular highway.  The numbers below correspond to the numbers in the sketch.

1.  Entrance Ramp		The car enters the tubular highway by moving up the Entrance Ramp.
2.  Acceleration Lane		The car moves to the right, from the Entrance Ramp into the Acceleration Lane.  In the Acceleration Lane, the car accelerates to its required cruising speed.
3.  Ascent Curve		After the car has attained its required cruising speed, it moves to the right onto and up the Ascent Curve.  Aerodynamic force holds the car firmly onto the surface as it proceeds up and around the Ascent Curve and into the Merge Lane.
4.  Merge Lane		The car travels in the Merge Lane in its fully inverted position.  Aerodynamic force holds the car firmly against the surface.  From the Merge Lane, the driver guides the car into the Cruising Lane.
5.  Cruising Lane		The Cruising Lane is used for long distance, high speed travel.  Entrance into the Cruising Lane is from the Ascent Curve.  Exit from the Cruising Lane is onto the Descent Curve.
6.  Descent Curve		Continuing to move at its required cruising speed, the car moves down and around the Descent Curve, into the Deceleration Lane.
7.  Deceleration Lane		The car decelerates in the Deceleration Lane.  After it has attained a safe exit speed, it moves onto the next available Exit Ramp.
8.  Exit Ramp		The car uses the Exit Ramp to leave the tubular highway.

There's one important feature of the tubular highway that I didn't try to show in the sketch.  That feature is the Service and Debris Platform, which should extend for the entire length of the tubular highway.  The Service and Debris Platform is a horizontal surface approximately midway up the elevation of the tube.  It serves as a roof over the lower part of the tube, where the On Ramps, Acceleration Lanes, Deceleration Lanes, and Off Ramps are located.  Of course, it doesn't extent laterally to the Ascent Curve or to the Descent Curve.  Those areas must be unobstructed to allow for their use.

In addition to providing a handy location for service equipment and service personnel who should, by the way, receive hazardous duty pay, the Service and Debris Platform will protect the lower part of the tubular highway from high speed falling debris.

A tubular highway is a marvel of high-tech overkill.  It's complexity is appalling and a conventional flat highway will work just as well.  Nevertheless, it's my bright idea so I'll point out a few of its virtues.  The majority of the road will never be obstructed by debris.  Anything that falls from a car will simply fall off of the road and, probably, land on the Service and Debris Platform.  Similarly, accidents will automatically clear themselves from he road.  Travelers will not need to worry about the weather because the entire roadway will be enclosed.  People who live along the route won't have to endure all of that road noise because it will be contained within the tube.  The thing can be elevated, at the surface, or underground.  It won't matter to the people who're using it because they won't be able to see out.  The people who live along side of the thing can paint it to match their houses.  Finally, it will be such a financial boondoggle that government and industry will absolutely salivate at the prospect.

There are many problems to be solved.  I don't claim to have thought of all of them.  However, one thing came to mind.  Since all traffic flow is in the same direction, there'll be a tendency for an air flow to develop in the direction of the traffic.  That's a very bad thing because it will tend to reduce the aerodynamic force that's holding the cars to the surface.  Somebody will have to figure out how to keep the air from following the traffic.  Speaking of air, ventilation will be a serious consideration.  All cars will need to be very well insulated because the noise inside of the tube will probably be hellacious.  Lacking a view, cars will need to provide entertainment  Of course, if a car has a mechanical problem, then the driver has mere seconds to get it out of the Cruising Lane, around the Descent Curve, and into a safe location beside the Deceleration Lane before the car loses speed.  If a car loses speed, then it will automatically remove itself from the Cruising Lane and onto the Service and Debris Platform.  Of course, people calmly accept a similar risk in airplanes so there isn't any reason why they should be nervous about flying upside down in their cars.

Anyway, there's the idea.  Make of it what you will.  I happily anticipate that the things probably won't be built within my lifetime.