Wind powered cart goes faster than the wind, directly downwind

[tobermoryphil]

I've just noticed that ThinAirDesigns, one of the USDC "Blackbird" team , has posted on another site that they have heard "from the highest authority" at NALSA that a speed of 2.8 times the wind speed will be ratified.
There were faster runs, but some of these were at times 500 feet from the nearest wind speed sensor; the 2.8 run was never more than 100 feet away, so the wind speeds can be regarded as accurate. Nothing yet published in writing, but it should be very soon.

 

[Malo37]

I really hope nobody's goign to reply to this !

 

[tobermoryphil]

You have already!

However, I hope it has killed off this topic at last.

 

[awol]

This will be the same NALSA (sic) as faked the moon landings - will it?

 

[tobermoryphil]

This will be the same NALSA (sic) as faked the moon landings - will it?

Yes; chairman is currently Elvis Presley. As predicted by Nostrodamus.

 

[Wunja]

To qualify for a record, don't they have to do a run in both directions?

 

[Danny Jo]

To qualify for a record, don't they have to do a run in both directions?

That's not as impossible as it sounds. There is a photo somewhere of two yachts approaching each other on reciprocal courses in the Menai Strait - both flying spinnakers.

 

[Ubergeekian]

That's not as impossible as it sounds. There is a photo somewhere of two yachts approaching each other on reciprocal courses in the Menai Strait - both flying spinnakers.

Reminds me of Sea Scout dinghy sailing courses at Lochgoilhead ... applying the IRPCS is great fun when two boats on starboard beam reaches are approaching each other head on ...

 

[flaming]

That's not as impossible as it sounds. There is a photo somewhere of two yachts approaching each other on reciprocal courses in the Menai Strait - both flying spinnakers.

Pretty common in the Solent when the sea breeze kicks in in the opposite direction to the gradient wind.

 

[xxyyzz]

Nonsense it's impossible, it'd be getting energy from nowhere.

 

[snowleopard]

Nonsense it's impossible, it'd be getting energy from nowhere.

Don't start that again

 

[xxyyzz]

Don't start that again

It won't start itself, not without a push anyways...

 

[DJE]

Pretty common in the Solent when the sea breeze kicks in in the opposite direction to the gradient wind.

And when you get to the point where the two winds meet look up and you'll see all the gliders from Daedalus circling in the thermal overhead.

 

[photodog]

Wind Powered Cart Goes faster than the wind, directly downhill.

My car does this all the time. Whats the big deal?

 

[tobermoryphil]

The last word, I hope- scroll down a bit.

http://www.nalsa.org/

 

[xxyyzz]

It's clearly going downhill:-

 

[Paul_R]

This one may be going downhill. However it's blackbird - same URL, different picture that claims the faster than wind speed down wind.

Here's another URL with video of it in action.

http://zerocarbonista.com/2010/07/14/blackbird-travels-downwind-faster-than-the-wind/

 

[saltwater_gypsy]

I'm new to this business. Is this the sort of vessel they use?


http://i300.photobucket.com/albums/nn14/hectou/propellordrivenpropellor2.jpg

 

[greggron]

Were beans involved?

 

[Slowboat35]

SDDFTTW has long been a topic amongst experimental sailors that raises rehtoric, abuse, loonies and ire in the same way that flags and anchoring topics do here.
Ther is a world of difference, though, when discussing this topic between the one with two 'D's in it, and the topic with just one. Dead downwind faster than the wind sounds impossible to me but some disagree vehemently, just downwind is another matter as tacking (rather gybing I suppose)allows use of relative wind and thus perhaps - just perhaps, the possibility of beating the wind to the end of the run...

Search for the acronym above to get a flavour of the levels of zealotry involved - your eyes will soon glaze over!