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Broadband Blimps
mcabiling writes "SansWire Networks will demonstrate their "Stratellite" technology next week. For those of you who aren't familiar with SansWire, they plan to build a wireless network with balloons or "airships" as they call them.
"A Stratellite(TM) is a high-altitude airship that when in place in the stratosphere will provide a stationary platform for transmitting various types of wireless communications services currently transmitted from cell towers and satellites. It is not a balloon or a blimp. It is a high-altitude airship."
Looks like a blimp to me..."
A Stratellite is similar to a satellite, but is stationed in the stratosphere rather than in orbit
Sounds like an attempt to overcome the runaway expenditures of Teledesic's failed LEO project. The problem with these high-altitude sender/receivers is that--while they offer a technology solution--there is a corresponding weakness in application.
For example, latency in these systems make it unattractive for many internet applications (who wants to play FPS's over a spread-slotted Aloha CDMA system?).
And then there is the monstrous launch and maintenance expense...
Sigs cause cancer.
Something a couple of friends and I talked about ages ago was flying an ordinary wifi AP from an advertising balloon. Y'see, the longest run of CAT5 you can use is 300 feet. By coincidence, the highest you can fly a tethered balloon to (neglecting ATS zones) is... 300 feet.
why use nitrogen as a lifting gas. Everytime I pour nitrogen gas, it settles to the bottom. Maybe they have magic nitrogen.
--sig fault--
The idea of blanket wireless internet access for all is enticing, but what kind of battery life are you going to get in your Laptop/PDA when you need a PC Card that can transmit signals over Seventy Six miles to this thing? (Based on the Altitude of 13 miles and an expected wireless coverage radius of 75 miles)
Not sure about anyone else, but I lose an hour off my battery life for a wifi signal that barely reaches 100 feet.
Urge to post... fading... fading... RISING!... fading... fading... gone.
The things that make the stratellite airship not a balloon or a blimp, based on reading the fine FAQ are:
A communication platform that sits at 65000 feet and stays relatively still sounds like a dream come true. None of the cost of keeping a constellation of LEO satellites moving, none of the latency of geosync. This would also seem a great technology for providing ad hoc coverage to a remote area for a special event. Put a couple of moderately directional (say +23 dBi) antennas, one pointed at Black Rock City, and the other at Civilization, and you have low-cost temporary ludicrous bandwidth at Burning Man. (Feel free to substitute YOUR favorite boondock~based used-to-be-cool-'til-they-sold-out art festival if you are offended by BM)
I for one, welcome our helium filled stationary communication overlords.
How does the Slashdot Effect happen given that no slashdotters ever RTFA?
Is the article about that fat geek who's always at the corner Starbucks with his laptop?
"Have you ever thought about just turning off the TV, sitting down with your kids, and hitting them?"
This is gonna go over like a lead balloon.
These guys played too much Final Fantasy ...
Just imagine, now we can have network blackouts and weenie roasts at the same time! Who is gonna bring the smores?
"When God kisses Satan and the Incarnations applaud." "Death is dead. Long live Death!"
Sounds like something Hugo Drax would have dreamed up. We need James Bond to kill him.
Similar in concept but targeted at a different market. Their 'technology' link has some good info.
Techsphere
What's next? give controls to Barney again?
Barney: Hey can I pilot it?
Pilot: I see no harm in that
Barney: Wooooooarhhhhhhhhhhhhhhh
*crash n burn*
we don't want that now do we
because when I think of technology in the future, I think airships!
Also, random fact: The spire on the top of the empire state building was originally intended to be used as a docking point for derigibles.
These guys, Halo Networks, tried to do this with planes... I just love the ingenuity that comes from a lack of rational thinking!
"I'm a karate man. Karate mans bleed on the inside."
Throw some jumbotron advertising on the sides of these and I just might start going to seedy chinese food bars in the rain.
vk.
What additional constraits will be applied to companies that want to float zeppelins over cities? Given the recent restrictions applied to amateur rocket groups, I question whether their business model will...take flight.
It caught my eye because it had an LCD type screen displaying graphics/advertisements and was pretty cool I thought - more versatile than the old-fashioned banners towed by aircraft.
They had the US flag, fireworks screensaver type graphic, etc. Once they have a functional display and controlling computer on board, it shouldn't be hard to beam up stuff from ground control.
An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
Considering the immense air traffic over most parts of the modern world, I figured this idea might actually work, and would require basically zero investment beyond the cost of the roaming access points -- no need to invent crazy new technology when there are already perfectly good airplanes up in the air every day anyway. I figured the airlines could be paid a reasonable royalty from the fees collected from users of the network.
Sanswire site has been slashdotted. Thanks.
The difference in pathloss between the SSP (21km slantrange) and the edge of a 75 mile coverage circle (122km slant range) is only 15.3 dB. Not an insurmountable design figure. You might need to use a directional antenna at the edge of coverage, where a more omni antenna would suffice at the center.
How does the Slashdot Effect happen given that no slashdotters ever RTFA?
I'd be worried about outages caused my storms. Also, i would imagine the data would decay based on electricity in the air.
I think the closest thing to this idea would be to look at the statistics for weather balloons and see how they survive.
GroupShares Inc.
-------
artlu.net
Pioneer of wireless airborne communication:o rs/l/lawnchairla rry.htm
http://www.truthorfiction.com/rum
If this ever gets off the ground, I will be very worried the next time my network connection goes down.
This account has been seized by the GNAA. That is all.
for one welcome our hot-air overlords.
We might be able to have truly Global Internet access, being so high up provides a kick-ass way of sharing to a huge audience and being easily 'upgradable' it can move with the times. :D
I'd hate to see what happens to the people below when one comes down though, moaning and groaning....
"Honey the Internet is down again!?!" :P
has a new website
My question is: Anyone who has/had DirectTV understands "rain fade" - will there be a similar degredation of signal whenever there are thunderstorms?
An ounce of perception is worth a pound of obscure
Sideshow Mel (i think), after seeing Homer dangling from a hot air ballon at a football game: "Dear God, look at that blimp! He's hanging from a ballon!"
The One Rule Of Chess You'll Ever Need: Don't play someone who carries a kit in their bookbag.
Our subscribers will be able to sit in their home on a laptop computer while connected to the Internet at high-speed. If they need to go to the office or across town, they simply close the laptop and take off. When they get to their destination, they open their laptop and they are still on the Internet. If they need to travel to another city, they simply take their laptop with them and when they get to where they are going, they open their laptop again and they are still connected.
And
clear line-of-site to approximately 300,000 square miles
Now a rough calculation puts its radius of coverage at about 300miles
radius = sqrt( Area / Pi )
r = sqrt (300,000 / 3.14)
r = sqrt (95541)
r = 309miles
So the distance between a device and this airship is at least 300miles.
With that kind of range, is it realistic to have the gear in a laptop/cellphone?
Would it not kill the battery? I get shorter battery life just using wi-fi.
Would you need some kind of directional arial?
I'm sure they have thought of all this, but it does feel like they might be over-hyping the usefulness.
Paul Leader
When your link goes down, tell 'em Nathan Zachary DOSed you!
I'm sorry, our blimp is down right now--can I have someone call you back when it's up again?
Doh.
-m
http://www.invisik.com
From the article:
"At an altitude of only 13 miles, each Stratellite will have clear line-of-site communications capability to an entire major metropolitan area as well as being able to provide coverage across major rural areas."
So what makes a rural area a "major" rural area? A complete lack of people?
There are 01 kinds of cars in the world. The General Lee, and everything else.
Although the designers knew full well it could never be utilized for docking airships, due to crosswinds at that height. It was a strictly ornamental way to set a contemporary building height record.
Air Force Pilot: It is so easy to fly, that even a child can fly it.
Millhouse: Can I fly it?
Air Force Pilot: No you cannot.
Drill baby drill - on Mars
I wonder how good these things would be as a camera platform? Never mind the obvious big brother uses but it might do wonders for news service and traffic monitoring.
The difference between Canada and the USA is that in Canada healthcare is a right and gun ownership is a privilege.
" Held in position by 6 onboard GPS units connected to the ship's engines"
WTF? 6 onboard GPS receivers? What's wrong with one good one. Surely a =10m precision is enough, and if it isn't they could try a differential GPS setup with two receivers, but six?!
Imagine 802.16 on one of these things.
"A new life awaits you in the Off-World colonies. The chance to begin again in a golden land of opportunity and adventure. New climate, recreational facilities.....absolutely free. Use your new friend as a personal body servant or a tireless field hand--the custom tailored genetically engineered humanoid replicant designed especially for your needs. So come on America, let's put our team up there...."
"This annoucement is brought to you by the Shimato Dominguez" Corporation - helping America into the New World."
D6 63 0D 70 89 81 BB 8E 7B 7C 5F 5D 54 EA AB 73
That said, the balloon tethers are pretty heavy - the ones I've seen resemble seatbelt webbing (but only about 2" wide).
The difference between a zeppelin and a blimp is a zeppelin has a rigid airframe. That may be what they're talking about when saying it's an airship, not a blimp.
Any aircraft that gets most of its lift from lighter-than air gases and can be propelled against the wind is an airship. It floats in air and it goes where you want it, so it is an air-ship. Ok? Blimps are airships. Or dirigibles--different verbal approach, same idea, because the word emphasizes you can _direct_ the motion.
Several operations have tried this high-altitude business. There are issues with it but if you can make it work, the advantages over satellites should be clear. Why not use an airplane? Because the damn things use a lot of fuel and must move faster than the airship might be forced by shifting winds to move--relative speed matters with high-bandwidth connections.
The high altitude is chosen in part for the coverage range, but also to seek a layer of air where the average wind _force_ is lowest, to minimize the power needed to stay in place. With this design of airship they are going to have to turn to keep drag down if the wind shifts. True of all practical designs yet except spheres which have unacceptably high drag in _every_ direction--flattened disks called "lenticular" layouts might have lower inherent profile drag but have a tendency to pitch sideways to the wind that can only be combatted with fins that break the symmetry. So inevitably they will be blown off their ideal station point from time to time, the question is can they turn into the new wind fast enough to keep the divergence small. It depends on what the system users consider a small deviation at that range.
I would wait and see if their next demo comes off. Their last demo was about a year and a half ago, using Techsphere spherical airships. Just before the scheduled launch date their demo airship blew away! Nowadays Techsphere is persuading the Navy they can reliably operate for surveillance missions--I don't know if they paid attention to suggestions from people like me about how to reduce the drag of a sphere or if they have just had the good luck not to encounter severe winds in their demos yet. But meanwhile Sanswire has clearly washed their hands of Techsphere! Anyway they have been here before. We'll see I hope.
The problem with orbital systems is that the cost to launch an object in to space is extreme. Furthermore, once it is in space, hardware upgrades are completely impossible. Then there's also the issue of latency as you accruately point out.
.00013 seconds to go 25 miles. Compare that to satellite service where you typically get .5 seconds of latency.
But with a blimp at 65K feet, you solve all of those problems. It's cost is primarily in assembly. Getting it on station is just a matter of letting gravity do it's thing. Once it's there, if you need to perform maintenance on it, you launch a replacement, and then bring down the old blimp for repairs. As for latency:
C = 186K miles per second
Distance to cover: about 25 miles round trip
So, if it can go 186K miles in one second, it would only take
Now, what I am curious about is the survivability of these blimps over the long term in the stratosphere. How will weather effect the quality of the services provided by the blimp, etc?
The other thing that occurs to me is that blimps like this could totally replace satellite coverage even outside metro areas. Create a mesh network of blimps and then route signals from blimp to blimp to cover wider areas. This would allow for far greater bandwidth than provided by satellites at a much lower cost. Furthermore, this is much better suited to creating redundancy, allowing blimps to reroute if there's an outage.
This sig has been temporarily disconnected or is no longer in service
Spaceship One Launch goes through Stratellite and cuts off cell phone service in the Mojave Desert.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
It might cost less and be more wireless friendly to use a solar cell and a battery. It'd also require less maintenance. A lot of street lights and signs are powered this way.
"He's more machine now than man, twisted and evil."
register one, your slash id is the number.
That which is done from love exists beyond good and evil
This is all hot air based phoney-balooney.
In order to adjust buoyancy. Nitrogen makes up 70% of air so unless your nitrogen is especially dense/cold it shouldn't settle to the bottom. Alternatively it could be acting as a solar hot-air balloon by making the envelope a dark colour to absorb heat from the sun decrease the density and increase lift.
Government of the people, by corporate executives, for corporate profits.
I am guessing there is no way to diable that pop-up.
And they claim to have "duel envelopes". Do they walk ten paces, then turn and fire?
Besides their bad spelling, they don't address some other problems. Like just because the airship is at a height of 13 miles, doesn't mean that's how far it is from your cellphone. That's how far it is from the nearest point on earth. What about the distance to the edge of the coverage area?
Also, won't this technology force far more people's data into the same limited frequency bandwidth? I mean, currently, 2 people on cellphones that are 300 miles from each other can't interfere with each other's available bandwidth, because the signals don't reach that far (and don't need to). But with airships like this one, they will interfere. You'll be wedging 1 million people's traffic into the same frequencies that currently only handle 1000. Can that be done?
In the wired world, more wires equals more bandwidth. In wireless, there's no equivalent, there's only one "air".
Seems to me that this thing is begging to be DoS'ed by IP over Avian Carrier.
A Stratellite will have ... clear line-of-site to approximately 300,000 square miles, an area roughly the size of Texas. However, the Company's initial plan is to use one Stratellite for each major metropolitan area
Why is a complex airborne system more efficient than little ground towers in cities? It seems that huge swathes of rural areas would be better served by such a scheme. OK, so there aren't as many potential customers but there isn't any competition either. Small towns of a few hundred people are scattered all over rural Texas, Kansas, Oaklahoma, [insert midwest state here]. They might not rate a cell phone tower and certainly not cable internet but one of these things could serve hundreds of such communities.
It also seems this would be perfect for risky places like Afghanistan and Iraq. Hard to car-bomb communications infrastructure that's at 60k+ feet up in the air.
One of the beauties of a high-altitude platforms (HAPS) is that its altitude can be controlled. Therefore, its potential footprint can be a small or as large as necessary. Also it can be deployed at a moments notice making it of particular interest to the armed forces. It can also avoid the difficulties of site acquisition, which is become a critical concern when deplying wireless systems.
However HAPS is not without its problems. For instance, HAPS can poise regulatory issues by creating possible interference to systems in adjacent frequency bands and services in the surrounding areas.
The thing is, they design for a particular altitude where the wind force is least. (Winds are fast, but the air is thin, and it works out to the least force). To descend from there means taking on stronger winds though if you plan to operate there all the time you can put more helium in and have a more robust ship. Vice versa to ascend beyond design height means you need to scant the helium meaning you cut weight to the bone--or have to redesign, and since wind speeds really pick up up there the forces are actually greater.
So until we have airships with _lots_ of structural margin, stratellites will pretty much have to operate at one level they are designed for, probably this optimum minimum wind force height.
Sanswire folks are trying to get an airship to reach a desired altitude of 65000 feet. The navy has been working with blimps lately which top out at about 20,000 feet, which I would consider pretty good. 65000 on a rigid frame ship is pretty unlikely. However, the unlikelyness of their statements does not make any dent in my plans to steal one and go airship-piratin'. Yeeaaar, matey. I'd like to be the first airship bucaneer, if I may.
TallGreen CMS hosting
JP Aerospace has a good track record with dozens of launches to 100,000 feet, so the technology's there.
Given that current gear requires a lot of power and massy equipment to deliver gigabits of data, having one (or more) airships per city is a good idea, although I'm fonder of manned stations such as JP Aerospace proposed (their Dark Sky Stations).
See the Slashdot discussion here
There is nothing wrong with yr Internet. Do not attempt to adjust the picture. We are controlling the transmission - NSA
Somehow these Dave Matthews lyrics seem more appropriate with a little spelling alteration...
Stratellite in my eyes
Like a diamond in the sky
How I wonder
Stratellite strung from the moon
And the world your balloon
Peeping Tom for the mother station
Blimpii, of course. Figured you'd know that...
"Each airship is 100% reclaimable" That's of course, you don't lose ground station control :) ... Not sure they know if their proposed technology will withstand the environment up there, which is somewhat different from suborbital or terrestrial elevations. I used to work for a startup that partnered with Orbital Sciences on a similar idea (1997). The balloons (we called) or blimps are feasible, especially with technology now offered today--we proposed a goretex+kelvar composite material for our balloons. We concluded that unless we shared ground station services (i.e. not dedicated), it would be to costly. That was during the time OSC/Orbcomm's venture flopped, so we had to build our own stations. Could be a reason I'm in another job currently... In the end, the operating costs out weighed the benefit compared to a LEO or even a land-line fiber solution [at the time].
BTW, for kicks, here was our competition back then
(funny): http://www.wired.com/wired/4.09/es.sky.html
Also, I worked with a company called iBlast, which has a cheaper approach to this (i.e. bandwidth reuse):
http://www.iblast.com/how.php3
Then again, guys have gone 'down' to flying helicopters with transmitters/receivers/repeaters to provide high-bandwidth comm links for very brief moments of a day (i.e. 2-4pm)
Man, times have changed (sigh)...
">>Yes, of course it's the right cabl [le0: NO CARRIER]"
:D
What the hell did you do?
Anchor the balloon with CAT5 Ethernet cable instead of Kevlar rope?
Does Cartman count as a broadcast blimp? He's fat, loud and obnoxious and broadcasts every complaint.
They seem to be more interested in their Stratellite(TM) than the Wi-Fi aspect. I suspect getting their high altidude airship in place will be the easier part of the project.
Issues not covered on their site:
What standards, if any will they be using?
Will it be 802.X or will they develop their own Standard(TM)? Developing their own could be very expensive. And who will make the hardware for it? Will consumers pay the price?
What about power? The FCC restricts 802 to 100-200mW. If they want more they'll have to "pay off" the FCC and for that they'll probably need $100,000,000+, a very high initial investment.
Until we see more info on overcoming the bandwidth, interference, and power problems we'll probably have to conclude that this is all hype.
Wish I had mod points.
The most damning error is in consideration of dimensions v.s. displacement on the same webpage. Given that length x height x width = cubic feet (displacement), or L x H x W = D, and the website gives us everything except for width (W), then we have:
( L x H ) x W = D
W = D / ( L x H )
W = 1.3 million / ( 245 x 145 ) = 1300000 / 35525
W = 36.6
Imagine, if you will, an object 245 long by 145 high by 37 feet wide. Indeed "it is not a balloon or a blimp"; to me it sounds like a giant lighter-than-air GARAGE DOOR!
The same calculations with a guessed width of 370 feet provides for almost 13 million cubic feet displacement. Maybe somebody more cynical than I can calculate if 1.3 or 13 million cubic feet of helium are required to lift 3000 lbs at 65000 feet.
In the mean time, I'll hold my investment money for use with a operation that can get the details straight.
SpaceData announced a similar service three years ago. This service is for narrow-band communications and focuses on telemetry applications. It is cooler than the SansWire system because the base station is attached to a weather ballon which falls out of the sky and crashes to the ground every couple of days!
From the Federal Aviation Regulations:
- Airship means an engine-driven lighter-than-air aircraft that can be steered.
- Balloon means a lighter-than-air aircraft that is not engine driven, and that sustains flight through the use of either gas buoyancy or an airborne heater.
Unfortunately, they don't define blimp.
There's been some SBIRS contracts from the government for the developement of manned/unmanned very high altitude airships with large electrical capability. The idea is the dev costs for this airship are large, so go in with the military to develop a toy they want. Such an airship could use the solar array to "charge up" fuel cells over time while loitering, then use the stored power for high demand applications like AWACS radars, electric weaponry such as microwaves or lasers (or as it has been seriously proposed, a laser mirror repeater for the ABL). A great recon and monitoring asset, relatively cheap, hard to kill with third world weapons, and you get some chump company to work out the details of making it into the commstation of doom, since the military is begging for bandwidth.
Makes one wonder who are the initial investors...
First company to offer me affordable wireless broadband gets my loot! Costs me 70 bucks a bunch total for a phone line I only use for internet and a dial up connection. It's obvious that none of the wired broadband options are ever going to happen this century, not for the bulk of the rural US they aren't. No one gives a crap, they only want to quad wire + quad wireless enable like starbucks and within two blocks of them, and that's it. They don't care about the rest of the market. Fine, I'll spend my money with someone who DOES care. Current satellite wireless is OUTRAGEOUSLY expensive, like 7-8oo clams just for the additional hardware, then 70 a month for a so so connection. So these guys use some old tech with some new in an innovative fashion = "a solution" - good on them!
Of course, I wonder how they are going to keep them in place at that altitude. I don't care what they use for an energy source, that's a lot of wind to deal with to stay more or less stationary, so the cost and maintenance will be part of the connection price, wiggled in, but still, hope it works out!
hmm, I was thinking of lightning, but maybe there isn't much at that altitude? I don't know, must be some atmospheric/meteorological geeks here would know that.
... because every year, people-"power users" and whatnot, who drive the brand new market, who buy newlaptops INSIST they need the laptops much lighter than the year before. The battery tech is there, chemiccal reaction batteries reached a high point awhile ago. IF laptop buyers would indicate directly to the companies that they could "struggle by" with a laptop that weighed the same as the laptop they had just a very few years ago, and put the weight difference back into a REASONABLY sized battery that did what it was supposed to do, then laptops today would have much better battery life. Laptops buyers need to make up their minds, can they and will they physically carry one or two more lbs, to have the same power and feature set laptop they have now, but with amuch better battery in it? This "battery problem" solution is right there and it's dog squat simple. That's all it would take to get good life from them. The laptop makers are NOT idjits, they are giving "you" what you demand the most,and most people want stylish & lightweight over functional and good battery life. You can have stylish and functional and good battery life, but not at two lbs or something ridiculous like that, not today anyway. You *need* a modern 3 lb laptop with a two lb battery, so that means between 5(one decent sized non toy sized battery) and 7 lbs (two beefy batteries onboard), and that's just reality, and they don't make them like that anymore because people refuse to carry them or buy them, it's "too heavy" for them or something. Catch 22, you need 3 things, chose any two. The buyers decide, not the companies. Light and stylish won,. Battery life suffers, almost negating the significance of having a portable,people complain about battery life,but I doubt less than 1/100th of one percent of new laptop buyers ever bothered to send a letter to vendor-x marketing telling them they WOULD buy a heavier laptop with the same features as the "cool" new lightweight version but with a whopper batt or two, an all day battery range in other words. I bet not even joe huge company that buys 1000 new laptops at a time bothers. But hey, it sure *looks* cool!
"Duel envelopes, both made of Kevlar" aparently the envelopes fight eachother.
Over rated? how the hell did I get modded overrated? If you feel my rating of 1 is to high, please, have a reason why it should be lowered. There are 3, Troll, flamebait, and offtopic. Overrated is for when there's realy not a good description of why a post doesn't deserve a score. It's generaly to be perserved for posts that get modded up to 5 that realy are only worth a 4 or 3, if it's the default, un-modified score, you should score it properly.
That which is done from love exists beyond good and evil
'Looks like a blimp to me...'
Looks like salvation to me.
Hihi, nice quote... "Stratellite is similar to a satellite, but is stationed in the stratosphere rather than in orbit". That's like saying "a square is like a circle, except that it has corners rather than being round"...
A 'stratellite' is not even close to being in orbit, because it's floating like an airship. A better "name" would probably be "strairplaine", but I guess that doesn't market well...
Sounds like you are talking about Space Data. Lots of former Orbital Sciences folks working there.
The difference between the half dozen of companies talking about providing this service and Space Data is that they are already doing it. Space Data has service in west Texas right now with the rest of Texas, Oklahoma, and Louisiana coming later this year.
Just weather balloons carrying a transcevier.
The technology for the electronics is here, just adapt it for the purpose. Keeping the platfrom in the air for months at a time, there's the problem.
Anyway, this is the only company I've seen that is already providing this type of service (not exactly broadband, yet).
Controlled by earth stations on the ground.
=D
folks you need to look close at the latest 10q for the parent company.. its a penny stock
"In news today, a Sanswire Networks Stratellite lost altitude and landed on a group of 6th graders who were on a field trip to a local museum. The company quickly issued a statement expressing their regret at the incident, and that they would be sending out a special retrieval unit to reclaim the broken dirigable."
That was during the time OSC/Orbcomm's venture flopped,/
The fact Orbital couldn't do something profitably doesn't necessarily mean that the technology is unworkable though. They definitely had problems with execution. Mission-critical hinges are not the best targets for component cost reductions. Large value inductors should be characterized over frequency before you stick them in a feedback control loop, especially when the component supplier tells you that. Oh, and when you burn a non-eraseable antifuse FPGA, it helps to debug the timing before you launch the thing into outer space.
Hi CmdrTaco. Welcome to Slashdot, where we have read about this about a jillion times already.
Can we please stop pimping "prototypes" and "plans" for this technology over and over and over again. How about waiting until, you know, they actually put one up there, and keep it up, and get it, you know, working. Please. Please.
If you were blocking sigs, you wouldn't have to read this.
It would be silly to design one that operates at both altitude and sea level. What I did not point out in showing that an airship can maintain the same speed with the same props is that when it does so up high it suffers far less force than down low--I said that but did not point out that this means the ship is way overbuilt for that high altitude then, if it can take the same speed at sea level. Therefore if the mission is to operate up high you make it far weaker and lighter and operate it very carefully, at reduced speeds, down low. You might go for constant aerodynamic force the way an airplane does, and thus like an airplane need less power down low (except planes also need extra power to take off and to climb--equilibrium airships would not!) We _choose_ not to use full power, to avoid wrecking the ship!
This is why solar power works so well for these things. Up high the air is very clear, you are above all the mist and dust and air itself is pretty transparent, and also very thin there. So there is a lot of power where it is needed and if the ship is brought down, it needs less so the fact that there is less light down here is OK.
So I don't have to get into an argument about whether internal combustion engines are even feasible up there or not--they are not the wisest choice of power plant up there anyway.
I was making a point with my example and assuming an airship that only went from sea level to some moderately less dense level, one where human beings could still breathe. Remember that the airship can only be filled with as much helium as it can retain at the highest level it reaches, which means it is underfilled down low, so it is desirable to limit the range of altitudes it is expected to operate in.
Again
and Yet Again
must the dang thing look like a killer whale?
If you must moderate, please moderate as irrelevent, not something bad, because I'm sure someone will find this interest
I was referring to a television show where Dr. Addison Bain, the major author and advocate of this implausible "theory" that seems to be uncritically taken for fact, proposed to show how dangerous the skin was.
However I do not watch a lot of TV and have not seen this show, nor any of the TV documentaries where Bain's claims are accepted as fact despite this embarrassing self-contradiction of a demonstration. I participate in a listserv devoted to airships and others on it, whom I trust on this, have very often repeated the story of Bain's demonstration. I have asked them to provide you with citations to this TV show or other documentation of Bain's embarrassment.
But meanwhile Dr. Alexander Dessler has written a paper that critically examines the core claims on their merits and shows that they are all invalidated by fatal contradictions with fact and logic:
The Hindenburg Hydrogen Fire: Fatal
Flaws in the Addison Bain Incendiary-Paint Theory
(3 June 2004: 480kb pdf file, 21 pages)
This is hosted at John Dziadecki's web site.
Slashdot's hyperlink policies are a mystery to me! I can't make these links show here, just type in
http://spot.colorado.edu/%7Edziadeck/zf/introd ucti on.htm
in your browser;
The pdf can be found, with other intoductory material, at
http://spot.colorado.edu/%7Edziadeck/zf/LZ129fir e. htm
Based on the descriptions I have read:
Bain had a sample of fabric he said was a piece of the fallen ship's skin--and indeed a lot of this allegedly unstable skin was left lying around on the field, kind of odd when you want to claim its conflagration destroyed the ship and sucked up so much oxygen that the hydrogen could not even burn! Not so odd if you assume instead that he airship's designers, mindful of the danger of fire, did their best to create a flame-resistant skin instead of one make of "rocket fuel" (and solid rocket fuels do not actually have the spectacular combustion features Bain suggests this skin has but failed to show--read the paper!) But he said he had an authentic piece of this skin--and proposing to destroy it for a staged demonstration strikes me as a crime against historical evidence in itself, but he did. However he did not rig a form of spark ignition or demonstrate that the skin could create sparks of any kind itself as he claims must have happened. He used a powerful flame source instead, and it did not cause the skin to burst into a rapid "thermite" like combustion--instead it burned slowly and dimly, almost going out, needing to be nursed along. This would explain how come he had some skin to destroy, and also I think it shows that the stuff was carefully developed by the Zeppelin company to be as _fireproof_ as possible, but it seems to directly contradict Bain's claims, don't you think?
The idea that the skin _could possibly_ be more risky than the the hydrogen could only have two merits--one being that the skin could somehow release more heat or at a more rapid rate, which claim Bain makes. He also says the skin design and composition allowed it to _self-ignite_ but never demonstrates this and the paper demolishes all the bases of this claim. If the skin could just create occasional sparks that would be a grave matter--but there too the Zeppelin engineers did their best to avoid this and the way that Bain says it could is quite contradicted by engineering details he ignores though they are no secret (just obscure--you have to care about airship history to know about them).