NASA-funded R&D engineers are working on plans for future spaceships to enter orbit around Mars using a doughnut shaped, steerable balloon-chute to slow down by flying through the Red Planet's atmosphere. Global Aerospace concept of "lifting-towed-toroidal-ballute". Background: Tharsis Ridge, Mars. Nobody believed Zralthar …
I'm right in thinking they'd still need all the paraphernalia of rockets, fuel etc to get the crew off Mars once they'd landed?
INRS but maybe a VAMPIR drive could be used to slow the craft down as it approached Mars instead?
Just a thought.
Oh, it's one of.... "those"
Yet another business designed on the model of consuming R&D money for profit.
So a flying haemorrhoid cushion huh?
Off-setting a toroid will produce a minuscule reaction. Added to this is the problem of its tether not acting through the payload's centre of mass.
Super high-tech software modelling of the dynamics.......hmmm
Computer says no !
How do you deploy an inflatable ballute from a craft entering an atmosphere at 20km/s? How do you keep the ballute attached to the craft? How do you Stop the ballute deflating if it's hit by a micro-meterorite? Hmmmmmmm. Nice try fellas.
another supersonic shockwave rider, how 1960s.
XB70 did it. Now thats what I call variable geometry
Such easy questions.
The answers are, in order:
1) Press the "deploy" button and, when that fails, poke it out with a straightened wire coat hanger.
2) Duct tape.
3) Duct tape.
Ballute or Balute
Reading the discussion of the Ballute took me back to the Philippines and their most disgusting "delicacy", the Balute. Rather than spoil anyone's meal while reading about the double L version of the Balute, here is a link that describes in great detail -- almost too much detail -- the, no pun intended, ins and outs of a Balute.
I suspect one of their plans is to deploy this device while in the very uppermost parts of the atmosphere (where the 'air', and hence drag, is very low indeed), and do so whilst at a relatively low angle of descent (you know, more like 'almost' following the shape of the planet, a decreasing orbit, rather than attempt a 90 degree free fall towards mars firma.. although I suspect the later stages of descent will feature this kind of angle).
I presume they will keep it attached with an (to me) unknown number of cords of (to me) unknown composition.
micro meteorites? tough call, I have no idea. Mind you, once they encounter the mars planetary defence system that will be the last of their worries.
Ballute is rubbish
Paraloon is much catchier
It's a shame no one has come up with a way of recovering some of the energy wasted during re-entry. Perhaps deployable turbine- or propeller-type blades to caputure the energy for electrical, chemical or mechanical storage. It could provide a useful form of power for use on the surface. It would mean an increased payload but might prove cost effective over several missions particularly if the recovered energy could be stored on the planet for use by later missions..
VAMPIR? Are you sure you don't mean VASIMIR?
Regardless, when you're talking about large ships, and sensible (in terms of human endurance) flight times, even a plasma-based thruster uses a fair amount of fuel. It depends just how light a feasible ballute can be made.
Nice thought, but even assuming you could capture the energy, any capture and storage system would be wasted mass on the outgoing flight - a mass far greater than the mass of fuel saved.
any fule kno the old ballute braking ploy...
Hmm, quoting from the Odyssey File (the book of the making of 2010 by Arthur C Clarke and Peter Hyams)...
"We have arrived at the Rectal First Big Ballute Plasma Shower Gas Saving Low Energy Fart Aerobraking Manoeuvre As Conceived By Arthur C Clarke (It can also be referred to as the old R.F.B.B.P.S.G.S.L.E.F.A.M. ploy)
mmmmm mars.... doughnuts...... mmmmmmmm interesting article..... doughnuts......
King's AIR&dD Movement and Fleet of Virtual Force? *
"mmmmm mars.... doughnuts...... mmmmmmmm interesting article..... doughnuts......" .... By Anonymous Coward Posted Friday 17th April 2009 15:05 GMT
Cheltenham on a roll, AC,and finally waking up to the madness which rules them? I wonder if they've discovered the algorithms which direct and permit spaced travel or whether they are condemned just to monitor IT?
One always hopes for the best but one is seldom disappointed with the failure of their success, which makes them look like Right Royal Charlies/Pukka HMGCC Wallahs.
* And a Pertinent Impertinence and Direct Question of Wales in Stupendous Times for Momentous Tomes.
"How do you deploy an inflatable ballute from a craft entering an atmosphere at 20km/s? "
You deploy it outside the atomosphere. The clue is from *outside* the atmosphere. Inital atmospheric pressure is a millionth of ground level. Its *differential* pressure that keeps it solid.1KPa (c0.147psi) is enough to keep it rigid at this altitude. The vehicle is enteriing at a shallow (<10 deg max) angle to the horizontal.
How do you keep the ballute attached to the craft?
I'll presume your looking at the cords. Both Alumina and Zirconia based fibres are available (Melting point to 1800c/3300F) but its not clear if this is available in long form. Carbon fibre would need protection. FeCrAlY is in wire form and usable to 1400c. The ami is to keep the deceleration low and the lift high.
" How do you Stop the ballute deflating if it's hit by a micro-meterorite?"
Initial work on this in the 1960s has the high temperature mesh/fibres on the outside with the pressure membrane. Its an inside out tyre.
"Yet another business designed on the model of consuming R&D money for profit."
Ex NASA guys get their old buds to cough up some cash to pursue their pet project.
Sure sounds that way. But this idea has knocked round since the 1960s and it should be pushed further. SBIR is a good idea in theory but I wonder just how many of those SBIR start-ups actually blossom into self-financing companies with *real* incomes and products someone can buy. Otherwise its basically corporate welfare.
Mine is the one with the basic re-entry book written in the 1960s in the pocket.
"any fule kno the old ballute braking ploy"
Mine's the one with the copy of Down with Skool in the inside pocket.
not only on Mars
It would seem that the space shuttle could use a safer means of returning to earth.
Of course the shuttle only uses fuel to slow its orbit so that it enters the atomosphere. But, relying only upon a heat shield has proven deadly.
Maybe a donut is not the best shape. And materials are key. But, the idea of using a large lightweight object of some kind to slow reentry/entry might make a lot of sense (economics/engineering). And maybe a propeller shape of some kind might even serve to recapture some energy. Maybe a big corkscrew? Adjustable of course. And perhaps one that breaks down into an autorotational set of blades.
Yes, yes, I did mean VASIMIR.
In fact looking at it now I've no idea where VAMPIR came from.
I think we're all agreed though. This idea is pants.