On 23/07/2010 09:01, Keith Willshaw wrote:


"John Doe" wrote in message
...
usenet jac.users.panix.com (John Clear) wrote:

John Doe jdoe usenetlove.invalid wrote:

How far-fetched is the idea, to use a propeller or jet engine
(radio controlled type?) to push an in-line skater? How does
aircraft takeoff thrust compare to using a conventional motor
and wheel to push oneself along the ground? What sort of
incline would be achievable at say a skater weight of about 160
pounds? I think the rolling resistance can be assumed to be
zero or maybe the same as a small aircraft.

Years ago (maybe late 1990s) one of those 'whacky invention'
type TV shows featured a guy with jet engines mounted on the
tails of his skis. No need for a chair lift, he'd just ski
uphill.

Inline skating is like a combination of different sports,
including skiing. One unique difference is that in-line skating
requires man-made terrain.

So it has been done, just make sure your life insurance is paid
up.

If you wear lots of protective gear and consider the risks, safety
should not be a concern. On TV, you see skaters and cyclists who
do not wear protective gear, apparently many people enjoy seeing
the accidents, but I just change the channel. Carelessly riding
a large displacement motorcycle years ago makes anything I do now
days pale in comparison. This

Still researching the issue, but by the lack of detailed comment,
I get the impression that propeller power is nowhere near
efficient as conventional motor and wheel on the ground
propulsion. That is the question.
--

No that is the answer.

Keith

Jet / Propellor / rubber band. It doesnt mallet what the power supply is.

Work out where the center of thrust/pull is - Probably if on a skater
approx 1.2metres up.

When the skater hit a bump to large for the front to quickly rise over,
the skater kisses the ground.

Think water skiing - It is a challenge to get up o the skiis, and then
the second you relax, and let the ski dig it, you are in the water