Wind Powered Cycles


Paul asked:  I wanted to know where I can learn about what determines whether a human/wind powered vehicle is “Street Legal?”  I saw a Pterosail online and wanted to know what makes this a street legal vehicle.

I am working with at-risk children and am interested in having them build these as projects that they can ride and which will set them apart from other children.  I believe this will give them a sense of accomplishment and pride.


Good one!  I hope you have success in your very worthwhile endeavors.

A Pterosail is a vehicle.

s. 316.003 – Definitions

(75) Vehicle – Every device, in, upon, or by which any person or property is or may be transported or drawn upon a highway, excepting devices used exclusively upon stationary rails or tracks.

And it is included in the very broad definition of traffic.

(57) Traffic – Pedestrians, ridden or herded animals, and vehicles, streetcars, and other conveyances either singly or together while using any street or highway for purposes of travel.

As strange as it may seem, the definition of “motor vehicle” seems to not preclude this vehicle type when under sail only.

(21) Motor Vehicle – Any self-propelled vehicle not operated upon rails or guideway, but not including any bicycle, motorized scooter, electric personal assistive mobility device, or moped.

It may not be classified as a “bicycle”.

(2) Bicycle – Every vehicle propelled solely by human power ….,

and including any device generally recognized as a bicycle though equipped with two front or two rear wheels.

The term does not include such a vehicle with a seat height of no more than 25 inches from the ground when the seat is adjusted to its highest position or a scooter or similar device.

Normally, we would argue that an operator of a recumbent with a seat height of less than 25 inches (Technically not a bicycle) has the same rights and duties on the roadway as other drivers since it is a human powered vehicle.

s. 316.2065Bicycle Regulations

(1) Every person propelling a vehicle by human power has all of the rights and all of the duties applicable to the driver of any other vehicle under this chapter ….

Since the Pterosail under sail power only is wind powered and not human powered, it could be argued that it is not human powered, and therefore does not have those rights and duties under the Bicycle Regulations.

The argument could also be made that it is just another human powered vehicle, and is a “device generally recognized as a bicycle though equipped with two front or two rear wheels.”

I don’t believe there would be any problem operating on a paved shoulder, since it is not part of the roadway.

(42) Roadway – That portion of a highway improved, designed, or ordinarily used for vehicular travel, exclusive of the berm or shoulder.

I believe the provision in that definition that gives credence to the use of the Pterosail on roadways is the definition of “roadway” above, since roadways are designed for the use of vehicles.  A marked bike lane is part of the roadway.

However, since the status of the Pterosail is unclear, ie, not clearly a bicycle and not fully human powered, there are safety questions that do not seem to be fully clarified by the statutes.  Bicycles are exempt from the requirements for “motor vehicle” lighting, turn and brake signals, brakes, etc, since bicycles, by definition, are not motor vehicles.  Some might argue that those exemptions do not apply in this case.

I note that the Pterosail website states “Made for the Road: Street Legal”.  Before operating a Pterosail in the roadway, I would suggest asking for the manufacturer’s proof of street legality in the state in which it is to be used, and compare that with the definitions herein.  It would be interesting to hear the comments of the police officers and the operator at the stops in the video.

I will attempt to contact the Pterosail folks and ask about their justification for the “street legal” determination.   I will ask them to respond as a comment on this post.

16 Comments on “Wind Powered Cycles

  1. This message sent this date to and

    Dear Sir/Madam,

    I received a request for information about the “street legal” status of the Pterosail in Florida at the site Ask Geo and responded with the applicable laws. Please review the question and my response on the site and provide your justification for the street legal status as a comment on the site. This is the link to the question and my answer.

  2. I also sent them a query the same time I sent to this site. So far, no response. I’m not sure they will respond.

    They are asking ~5,800 for their bicycles shipped, tax NOT included. I’d expect they would be more forthcoming with documentation to support their claims when asking people to pony up such a sum.

  3. The support email address above isn’t a live address. It keeps getting bounced as a fatal error. I also tried to call the number listed for contact at The machine answered in John’s voice, and I left him a message and asked that he call back. Unless they give us more to go on, I suggest the above is the best info available.

  4. This brings to mind an interesting question: what if human power is used to charge a battery or flywheel, which can then be tapped for forward thrust? Is this operation solely by human power?

    • Well, no, the energy stored within the wood is the propulsion. You don’t create that energy by chopping it down.

      I think the flywheel concept has a better chance of counting as human-powered.

  5. Thanks you for your explanations and research Geo.

    I have yet to receive an email reply from pterosail and so far they have not replied here.

    I am starting to wonder if they are misleading customers by giving the impression that the cycle is “street legal.”

  6. Would a vehicle propelled by pedals with four wheels be legal to drive on the street? Like a pedal cart. Since it is propelled solely on human power.

  7. Yes. The law says “human power”, so unless it is specifically prohibited by other provisions in the statutes, such as skates for example, it is legal.

    s. 316.2065 –Bicycle Regulations

    (1) Every person propelling a vehicle by human power has all the rights and duties applicable to the driver of any other vehicle under this chapter, except as to special regulations in this chapter

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