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Sanswire Demonstrates First Stratellite
Sterling D. Allan writes "Pure Energy Systems News (PESN) reports that GlobeTel Communications Corp. debuted their Sanswire Stratellite last week to over 300 people, including members of the media, personnel from the U.S. Department of Defense, U.S. and international commercial interests, as well as investors and shareholders. Stationed in the stratosphere, well above the jet stream, powered by film solar photovoltaic units, the device will make wireless communications available anywhere in the U.S., including on airline flights. One Stratellite will have a payload capacity of several thousand pounds and clear line-of-sight to approximately 300,000 square miles, an area roughly the size of Texas."
From TFA: Wireless capability (currently) to an area with a radius of 200 miles.
They're not in space, they're in the stratosphere (part of the atmosphere).
65,000 feet is above the jet stream. All the bad stuff is below 50,000 feet.
Now, if they get a whole network of these (50+), they could cover the entire USA.
Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
They're planning to use such airships to launch ships into space, by slowly achieving orbital speed!
change the parent post to Funny rather than Informative or Insightful. The AC post was a joke, made up by the AC, me. Any resemblance to factual matters is purely coincidental.
It's called Helium
Me too. But as an investment, the NASA helios is a proven platform that just needs a bit of refinement. Maybe a Helios inspired GPL project? I'd be willing to run if there is sufficient interest.
It's 65,000 feet in the air, and is (From TFA) 245 feet on the long diameter.
.00006 (if I did the math right) degrees across. In case I did, it would be the same relative size as a 6 foot guy 1600 feet (About a quarter mile) away.
:D
That's about
IOW, if its shadow covers your house, you should be more concerned about your house than the shadow
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The Stratellites are unmanned airships and will be monitored from the Company's Operation Centers on the ground. I wonder what bandwith the connection with ground control would have. For large scale ISP services less than many many Gb/s would be insufficient. Anyone here able to estimate whether such would be a serious bottle neck or not? (I guess they might have just lowered a cable if it wouldn't be accompanied by giant lightning rod like properties)
Read this if you are sceptical about Sanswire claims.
They've been hyping this for years, and while the telecom crash of the early 2000s kicked the chair out from under their business plans, they'd still be really really cool if they ever deployed the bloody things.
By the way, their PR mockup picture of the Stratellite looks amazingly like the whale in the Hitchhiker's Guide to the Galaxy.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
You didn't do the math right. You incorrectly converted from radians into degrees. For high noon, with the thing directly overhead, the correct formula is (180/pi)*tan^-1(245/65000) which works out to about 0.22 degrees. That's about half the width of the sun, so this thing will never cause a complete shadow, just a 1/4 dimming over an area with length about 250 feet and tapering off to 0 at an area with length 500 feet.
Quid festinatio swallonis est aetherfuga inonusti?
Africus aut Europaeus?
Imperial units weren't established until 1826, long after American independence, and were never adopted by the U.S. Among other differences, one was a different definition of the inch -- a U.S. inch was 2.540005 cm, and an Imperial inch was 2.53998 cm. In July 1959, the Canadian 2.54 cm inch was adopted as the International inch by the U.S. and the Commonwealth, but the U.S. continued to use the slightly longer U.S. inch (and foot/yard/mile) for surveying -- which includes surveys of Texas's area.
Accordingly, a Texas is not Metric, nor Imperial, nor even International, but purely U.S.
Let's assume that the props have to turn at 2500 RPM at ground level for the airship to keep station. If everything falls off proportionally, then at 65 000 ft, the props would still have to turn at 2500 RPM to keep station in a wind of the same velocity. However, aerodynamic drag would be much reduced due to the decreased air density, and so the energy required to turn the props at 2500 RPM would be much less. I'm not sure of the degree to which drag would be reduced, and this also doesn't take into account things like the constant friction of the motor bearings. But this part of their claims sound feasible to me.
I am an aerospace engineer. A few thoughts. . .
.) then they have a lift deficit of 3,750 pounds. They'll never get to 70,000 feet. They might get to 60,000 feet, but then they'll only have around 100-pounds of payload capacity available. Plus, the air is denser at 60,000 feet, the propulsive power is greater, the battery weight is higher, etc etc etc.
1. Regenerative power systems (the kind you can deplete and re-charge, whether that be solar cells and batteries, solar cells and closed-loop fuel cells, etc.) need to mature far beyond what is currently capable in order to make these craft work. Consider that the solar panels need to not only power all the essential equipment (radios, drive motors, wifi, etc.), but they also need to have enough excess to recharge batteries for night operations. For something very flat like the Stratellite(TM), this means they won't be able to operate too far north (or south) because the angle the airship makes with the sun will be too great - too few photons will be striking the cells. For the kinds of power densities they will need, this may mean not operating north of New York City, for example.
2. Now consider what happens at night. You have zero solar power - 100% comes from your storage bank (batteries, fuel cells, hyper-flywheels, etc). In the northern hemisphere at winter, you will need to plan on about 16-hours of power storage capacity before the sun gets high enough in the sky to start powering the ship AND recharge the batteries.
3. Assuming the nominal drag coefficient numbers others have talked about (~.05), an average airspeed of 40-knots, and assuming that the electric motors are 90% efficient at converting electricity to mechanical power, and that the propellers are 60% efficient at converting the mechanical power to useful work (thrust), this craft will need 45kW of power available 24-7 JUST FOR PROPULSION at 70,000 feet. 4. Assuming that their regenerative storage system has a power density of 100 Watt-hours per pound (which is optimistic), this equals 7,200 POUNDS OF POWER STORAGE REQUIRED! 5. Again, at 70,000 feet, assuming the structure weighs in at around 1,000 pounds (I'd like to see that. .
This sig is a test. If this had been an actual sig, you would be reading something quite a bit wittier than this now.