fuel less flight

[VJ]

Nice idea: a plane that could carry payload and passengers, but doesn't require fuel for operation.

http://www.gizmo.com.au/public/News/news.asp?articleid=3060

It uses buoyancy which creates an upward motion in order to gain altitude, and gravity acceleration which creates a forward and downward gliding motion. Hunt's website has a nice presentation of the principle...

http://www.fuellessflight.com/index.htm

Still, I wonder if this idea will - pardon the pun - take off...

Jörg

[Jammrock]

Very cool, but I hope it has some fuel power in case of emergency.

Jammrock

[Marshmallowman]

I think the boyancy thingy might make it quite fualt tolerant...seems like it should glide pretty well if it comes to that.

[Tjalfe]

Originally posted by Jammrock
Very cool, but I hope it has some fuel power in case of emergency.

Jammrock

You mean in case gravity stops working?

sounds like a plane shaped blimp more than anything

[agallag]

It doesn't use petroleum fuel, but that doesn't mean it doesn't take energy to run it.

Where do you get the helium from?
Once you reach altitude, is all the helium released into the atmosphere? That would require "refueling" for the next trip.
How efficient is their "vertical axis wind turbine"? If it's not 100%, then they won't be able to fly forever.

Neat idea to improve the efficiency of flight, but it's not "fuelless".

[Greebe]

Interestingly, because this hybrid plane uses technology of gliding and aerostatic lift, the idea for sustained flight actually has more in common with the older technology of Leonardo Da Vinci's first primitive hang glider, than it does from the Wright Brother's engine powered airplane only a century ago.

who ever wrote this, filled their head with such is a moron who needs a semester in aerodynamic engineering

First off the principle of aerodynamic lift is the same for all concerned, but there is a two fold difference...

Both are a heavier than air craft, tho one has an engine and could fly, the other never did because it was hopelessly flawed. Secondly the Wright Flyer is an enclosed frame structure, so it could conceivably be filled with helium whereas the Da Vinci Glider was an open stick frame structure that wouldn't ever.

Most people don't realise lift = forward motion because of drag, but if properly designed could maintain a level flight if there are headwinds, no helium required as proven by slope soaring gliders made today... typically achieving speeds far greater than headwinds would indicate. Example there are several places out in Cali (Point Furman for example) where combined with the Santa Anna winds of upto ~60knots have achieved speeds >200 knots.

The upper level winds of our atmosphere would allow for similar flight

[VJ]

Originally posted by agallag
It doesn't use petroleum fuel, but that doesn't mean it doesn't take energy to run it.

Where do you get the helium from?
Once you reach altitude, is all the helium released into the atmosphere? That would require "refueling" for the next trip.

The presentation on Hunt's website shows what happens: the helium is in flexible tanks inside solid thanks; air is pumped in the solid thanks, thus compressing the flexible ones. The helium is never released, but I wonder of fault resistent this can be made...

How efficient is their "vertical axis wind turbine"? If it's not 100%, then they won't be able to fly forever.

True... (there is an movie of the vertical axis wind turbine, they claim it has 44% efficiency)


Jörg

[Paddy]

Looks very cool.

[William]

Originally posted by VJ
The presentation on Hunt's website shows what happens: the helium is in flexible tanks inside solid thanks; air is pumped

Ding, ding, I spy external energy being added to the system. Pumps need energy to work; this has to come from somewhere (not withstanding, William has always liked airships as a concept)

[KRSESQ]

This reminds me of a cover illustration for Popular Science or Mechanics Illustrated from the 1950's, depicting a twin-hulled atomic powered(!) cargo derigible. I wish I could find that issue.

Kevin

[ALBPM]

Originally posted by Jammrock
Very cool, but I hope it has some fuel power in case of emergency. Jammrock

Methane..... just recycle passenger's

[Jon P. Inghram]

Originally posted by ALBPM
... just recycle passenger's ...

Anyone remember playing Star Control 2 (or the modern PC port, The Ur-Quan Masters?) The Druge used that technique, i.e. they burned CREW FOR FUEL!

[VJ]

Originally posted by William
Ding, ding, I spy external energy being added to the system. Pumps need energy to work; this has to come from somewhere (not withstanding, William has always liked airships as a concept)

Hmm, I used the word 'pumped', but Hunt claims the air comes from compressed air bottles, which are filled (and compressed using the turbines during descent). Still, I also think the cyclus cannot be maintained infinitely: I suspect there will be loss somewhere, resulting in less and less performance as the cycles go on...
Nevertheless, the idea is nice...


Jörg

[UtwigMU]

Originally posted by Jon P. Inghram
Anyone remember playing Star Control 2 (or the modern PC port, The Ur-Quan Masters?) The Druge used that technique, i.e. they burned CREW FOR FUEL!

Yeah, even worse thing was, when you sold your crew to them more than once.

[KvHagedorn]

Hmm.. when this can actually be proven to work, then it will be newsworthy. Until then, some pics of a couple of Zeppelins joined by a wing and a few paragraphs of mumbo-jumbo are just that.