'If you can tie it to a balloon, you can get to Near Space, (and) our prototyping efforts with communication and imagery platforms (are) showing promise towards giving us a low -cost persistent world-wide presence,' he said.

At first, the concept sounds like something out of Rube Goldberg. But Space Command is taking the concept seriously, and with good reason.

'Tests of balloon-borne ground-to-ground ground-to-air communications systems were staged to show the effectiveness of a low-cost, simple solution to meeting warfighter communication needs,' Space.com reported Wednesday.

'The trial runs involved balloon-born SkySite command-and-control platforms developed by Space Data Corporation of Chandler, Arizona. Space BattleLab is now adapting the system to provide a platform for its Combat SkySat communications system,' Space.com said.

The web site also noted that the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., is developing a disposable inflatable 'ship' or 'zeppelin' called the High Altitude Reconnaissance Vehicle (HARVe) that could stay in one spot 70,000 to 100,000 feet above ground level for two weeks to a month. Unmanned, it would be launched from either a cruise missile or reusable rocket and could carry out radar and imaging missions.

If the concept worked, it could later be applied to ballistic missile defense. For early warning radar arrays to detect incoming ballistic missiles could be mounted on massive mobile floating platforms high in the stratosphere they could provide crucial over-the-horizon lead time in detecting hostile missile launches and would be far more difficult to fool.

That would especially be the case if the current or future administrations push ahead with boost phase interception programs, which many scientists believe offer the best chance for destroying intercontinental ballistic missiles because they achieve full speed and become far more difficult targets to hit.

Nor would they themselves be fixed vulnerable targets on the ground, even though they would be operating far out of hostile air space and far from potential enemy fighters or anti-aircraft missiles themselves.

But the concept offers striking attractions to Space Command over many far more famous, long-touted plans to loft state-of-the-art military hardware into either Low-Earth Orbit (LEO) or High Earth Orbit (HEO). For stratospheric airship platforms could be far larger, carry far more equipment, and yet be far less vulnerable.

That is because any weapons system, offensive or defensive, that is lofted into LEO or HEO is inherently vulnerable because it is easily detectable and predictable. It must travel on predictable orbits. Even though satellites can be, and have been given engines and fuel to manoeuvre in orbit, the amount of fuel they can carry and therefore the number of evasive manoeuvres any of them can carry out is extremely limited because cost-to-weight ratio of sending any payload into obit even on the cheapest and most reliable 'Big Dumb Booster` available is always extremely tight.

Also, 'big dumb boosters` can never be really dumb. Rocket science is still demanding, and the United States simply is not as good as it used to be. In two of the last three tests of the anti-ballistic missile interceptors being deployed around Fort Greely, Alaska, the advanced and demanding electronic guidance equipment on board could never even be assessed because the supposedly far more simple, 'old-tech' rocket engines failed to ignite and even launch the rockets.

Building a new generation of 'super-zeppelins' would avoid all these pitfalls. Basic principles of physics would be on the side of the designers rather than against them as is the case with all ground launched space satellites. Lighter-than-air gas bags will do most of the real hard work of lifting the payload into the heavens.

It is true that the stratosphere -- with heights of up to around 70,000 to 100,000 feet, or 14 to 20 miles high, is not quite into low earth orbit of 200 miles up or more. But it is still very high, and the platforms would be far more manoeuvrable, and therefore unpredictable and less easy to shoot down than earth sats, especially those in LEO. Yet once the development costs of the program are completed, building the new platforms should prove much more cost-effective than putting small satellites on huge rockets into space.

The new airship concept has powerful boosters as well as Gen. Lord and Space Command. DARPA, the Pentagon`s Defense Advanced Research Projects Agency which can do no wrong in the Bush administration`s eyes, is all for it, and so is Defense Secretary Donald Rumsfeld, whose once limitless appetite for deep space programs has been whittled down by endless cost-overruns, project delays, system failures and increasingly harsh congressional criticism. As a result, the next space horizon the Air Force seeks to conquer may be a lot closer to home.