Will solar flight kill space business?

[orionrider]

Imagine you could launch a geostationary payload for just a few million dollars?
Say a data transmission relay or an Earth observation platform, or a positioning system, or an international cell-phone network...
Imagine you could easily recover and re-launch the platform for hardware updates, maintenance or replacement, essentially at no costs? Re-position or re-orient the craft without ever running out of propellant?

Well, it's becoming reality: viewtopic.php?f=19&t=25103

Other systems are in the making: unmanned blimps that can stay aloft for months or ultra-high-altitude, very long endurance UAV's, loitering for a week at 60.000ft.

If (when?) these low-cost platforms replace satellites, space business will become less profitable. This will dramatically increase the cost of deep space missions and manned spaceflight.

What do you think :?:

 

[ZiraldoAerospace]

Yes this may cut into the market, but I don't think that it will drastically effect the business in the long run. These solar platforms could easily be shot down it seems to me. It is much more difficult to shoot down a satellite. And there will always be a need for space probe launches and things of that sort. In fact, now that I think of it, this might actually drive down launch costs so that they are able to compete with this low pricing.

 

[orionrider]

It is much more difficult to shoot down a satellite.

Not so! A weather or communications platform hovering 20km above your own territory would be safer (also easier to defend and replace) than a LEO satellite passing several times a day above Korea, Iran and all the other 'potential' enemies. Apart from GS satellites which are virtually immune and military crafts with countermeasures, all the others are sitting ducks. Imagine the Korean lunatics deciding to shoot down all US birds 'violating' their territory?

this might actually drive down launch costs so that they are able to compete with this low pricing.

That is assuming that the price of space access is artificially inflated to provide huge benefits for the space business. I'm not sure there is enough margin to significantly reduce the costs :?

 

[neutrino78x]

this might actually drive down launch costs so that they are able to compete with this low pricing.

That is assuming that the price of space access is artificially inflated to provide huge benefits for the space business. I'm not sure there is enough margin to significantly reduce the costs :?

I think the original poster meant that it would be an economic incentive to develop cheaper space launch techniques.

Rail gun launch for satellites, anyone???

Awesome USN test of a railgun firing a projectile at 2520 m/s. (the plasma plume behind it is from from the heat caused by extreme velocity!

--Brian

 

[neutrino78x]

A scientific study of Railgun Launch (PDF file)

--Brian

 

[Valcan]

I think the original poster meant that it would be an economic incentive to develop cheaper space launch techniques.

Rail gun launch for satellites, anyone???

Awesome USN test of a railgun firing a projectile at 2520 m/s. (the plasma plume behind it is from from the heat caused by extreme velocity!

--Brian

I dont see things like this hurting the space launch buisness. Think about it how much do those big communication satelites cost? Now think about all the crap you have to deal with in a atmosphere. To me sending up a satelite is still gonna be much cheaper and easier in the long run.

 

[scottb50]

I dont see things like this hurting the space launch buisness. Think about it how much do those big communication satelites cost? Now think about all the crap you have to deal with in a atmosphere. To me sending up a satelite is still gonna be much cheaper and easier in the long run.

If it had a months duty and returned for maintenance and crew charge it might make a lot of sense. As it matures duty can be extended.

 

[docm]

IMO airships are going to make a huge comeback soon, especially for heavy lift air cargo and semi-stationary missions akin to what this aircraft is supposed to perform. Advantages: larger cargo capability and simplicity.

 

[DarkenedOne]

Imagine you could launch a geostationary payload for just a few million dollars?
Say a data transmission relay or an Earth observation platform, or a positioning system, or an international cell-phone network...
Imagine you could easily recover and re-launch the platform for hardware updates, maintenance or replacement, essentially at no costs? Re-position or re-orient the craft without ever running out of propellant?

Well, it's becoming reality: viewtopic.php?f=19&t=25103

Other systems are in the making: unmanned blimps that can stay aloft for months or ultra-high-altitude, very long endurance UAV's, loitering for a week at 60.000ft.

If (when?) these low-cost platforms replace satellites, space business will become less profitable. This will dramatically increase the cost of deep space missions and manned spaceflight.

What do you think :?:

1. We have had this technology for many decades now. Its called a weather balloon, and they are much cheaper than solar powered UAV. It is true that a solar UAV is powered, so I would imagine the most effective long endurance would be a solar powered blimp.

2. The problem however is that this technology is ok for light weight payloads, but not so much for heavy weight payloads. Telecommunication satellites often have the mass and size of a large SUV. No current solar UAV can carry that type of weight.

3. For a positioning system a moving UAV would be undesirable. GPS works because the GPS satellites are in Geosynchronous orbit so they do not move relative to the ground. A UAV that gets pushed around by the wind would mess it all up.

 

[DarkenedOne]

It is much more difficult to shoot down a satellite.

Not so! A weather or communications platform hovering 20km above your own territory would be safer (also easier to defend and replace) than a LEO satellite passing several times a day above Korea, Iran and all the other 'potential' enemies. Apart from GS satellites which are virtually immune and military crafts with countermeasures, all the others are sitting ducks. Imagine the Korean lunatics deciding to shoot down all US birds 'violating' their territory?

1. Why would the military fly a UAV over its own territory. The whole reason to use a UAV is to fly it over enemy territory,

2. Satellites are far safer because few nations have demonstrated the capability to take out a satellite. UAVs on the other have been shot down by ordinary fighter jet.

 

[scottb50]

1. Why would the military fly a UAV over its own territory. The whole reason to use a UAV is to fly it over enemy territory,.......

Communication comes to mind as a good reason. Flying down I-70 and sending tickets could be a dangerous idea.

2. Satellites are far safer because few nations have demonstrated the capability to take out a satellite. UAVs on the other have been shot down by ordinary fighter jet.

I think an F-15 took out a satellite once or tried to.

 

[ZiraldoAerospace]

That was the point I was trying to make DarkenedOne, it is possible to shoot down a satellite, but not many countries have the missiles to do that, whereas it is pretty easy to get something like a stinger or some equivalent and shoot an airplane down. And I was talking mostly about tactical sats anyway, orionrider, and as you stated, they are harder to shoot down than a regular sat. But yes, nothing is truly safe... Just different levels of safety, that's all.

 

[orionrider]

Why would the military fly a UAV over its own territory. The whole reason to use a UAV is to fly it over enemy territory

UAV is not always military. You can monitor crops, forest fires, storm damage, data relay, highway traffic control, oil plumes, weather, etc. All these things that are now done with satellites in LEO or GEO.
Such a platform 20km above for instance Chicago would be safe from all enemies, also terrorists. Portable missiles can't go more than 2km up. And fighter jets would be difficult to infiltrate.

For a positioning system a moving UAV would be undesirable. GPS works because the GPS satellites are in Geosynchronous orbit

GPS sats are not geostationary. That is why they need so much sats to cover the whole world, there have to be at least 4 above any point at any time :shock:
http://en.wikipedia.org/wiki/Global_Positioning_System

A UAV platform can use ground beacons to adjust it's signal according to it's current position. It is much more efficient than a constellation of passing satellites; because it is always there you only need one to cover a diameter of about 1,000km. :idea: To cover the whole of the USA, you would need about 15 low cost platforms.

Telecommunication satellites often have the mass and size of a large SUV.

Because they need to operate for years in GEO they require large power sources, thruster rockets and propellant, spinning wheels for orientation, High-power antennas to cover the large distance (included the whole of the atmosphere). A UAV can be built much lighter :idea:

 

[CalliArcale]

This won't kill space business. What it does is provide another tool in the kit for stuff like telecommunications and reconnaissance, the two biggest commercial and military uses of spacecraft. It's not ideal for all applications; it won't replace geostationary satellites or navigation satellites, and the relatively low altitude of the vehicles will reduce their effective range. Essentially, you are trading range for flexibility. The great advantage these have (besides start-up cost) is the ability for rapid deploy. A spacecraft takes years to put into place -- building the spacecraft, building the booster, and finding a spot on the busy global launch manifest. These autonomous UAVs could eventually be cheap enough that a provider might have a fleet of them on hand for when customers come knocking. That was the idea with NASA's Helios project as well, which unfortunately terminated early when the aircraft encountered a sudden gust and crashed on landing. So if you've got a fleet of these birds, a customer comes along with a payload, asks you to fly the payload over such-and-such an area, and you could have it up within a week. It could also be helpful for telecommunications at very high latitudes, where geostationary satellites can't really "see", and in other areas with restrictive horizons.

 

[orionrider]

You're right about the limited range of these platforms. Each time you need to cover the entire planet a satellite is superior. To monitor sea levels or for military observations for instance.
They will also open a new, parallel market, complementing space assets for all applications where GEO is currently too expensive and LEO not practical, like city traffic management.
But they will also steal a significant part of the pie. I think of the many Ku-band transponders in GEO: http://www.satsig.net/sslist.htm
Each could be replaced by a fleet of just six platforms and four spares (two in maintenance and two in standby). Ten platforms would be much cheaper than a single GEO satellite.

Right now, the GlobalHawk can reach 20,000m altitude and loiter for extended periods with daily air refueling. The next generations will be much more ambitious:

DARPA has set the goals for Vulture as five years on station with a 450kg (1,000lb) payload, 5kW of onboard power and sufficient loiter speed to stay on station for 99% of the time against winds encountered at 60,000-90,000ft altitude. Operating as a pseudo-satellite in the stratosphere and not low Earth orbit would provide a 65dB improvement in communications capability, and significantly increase onboard sensor resolution.

http://www.darkgovernment.com/news/darp ... o-extremes

http://www.darpa.mil/news_images/medium/vulture-02.jpg

 

[docm]

Stratellite

http://www.sanswire.com/

Power: solar electric

Prototype test
[youtube]http://www.youtube.com/watch?v=_mpKd0j5cFk[/youtube]

http://en.wikipedia.org/wiki/Stratellite

General characteristics

Length: 245 ft in (75 m)
Width: 145 ft in (44 m)
Height: 87 ft in (26.5 m)
Volume: 1.3 million ft³ (37,000 m³)

Performance

Service ceiling: 70,000 ft (21,000 m)
Dual envelopes, made of Dyneema (sometimes called Spectra)
Navigation: 6 onboard GPS units connected to the ship's engines
Payload capacity: 3,000 lb (1,400 kg)
Cruising altitude: 65,000 ft (20,000 m)
Lifting gas: Helium and Nitrogen
Line-of-sight: 300,000 mile² (777,000 km²)
Maximum duration aloft: 18 months

And the conventionally powered Bullet 580 is slated to start test flights later this summer.

http://www.e-greentechnologies.com/products.php

http://www.space.com/businesstechnology ... 00520.html

Airship Inflated to Create Monster 'Stratellite'

By SPACE.com Staff

A huge inflatable vehicle as long as a 23-floor skyscraper is tall has become the world's largest airship in its bid to serve as a stratospheric satellite, or "stratellite," according to its developers.

The 235-foot (72 m) long airship, known as the Bullet 580, has a top speed of 80 mph (129 km/h) and can serve as a high-flying sentinel that stays aloft for long periods of time. Getting the new sky behemoth inflated required six hours inside Garrett Coliseum in Montgomery, Ala.

"Our airships are radically different designs that move beyond the performance limitations of traditional blimps or zeppelins by combining advanced technology with simple construction and the ability to fuel with algae, protecting our environment," said Michael Lawson, chairman and CEO of E-Green Technologies.

The airship is designed to carry payloads of up to 2,000 pounds (907 kg) at altitudes of 20,000 feet (6,096 m). Any cargo aboard the airship would sit within an outer envelope made from a new type of Kevlar, or the same material used to build bulletproof vests. That allows the envelope to have a width just one-sixteenth of an inch thick, but still be 10 times stronger than steel.
>
>

 

[DarkenedOne]

Why would the military fly a UAV over its own territory. The whole reason to use a UAV is to fly it over enemy territory

UAV is not always military. You can monitor crops, forest fires, storm damage, data relay, highway traffic control, oil plumes, weather, etc. All these things that are now done with satellites in LEO or GEO.
Such a platform 20km above for instance Chicago would be safe from all enemies, also terrorists. Portable missiles can't go more than 2km up. And fighter jets would be difficult to infiltrate.

Non-military UAVs do not have to worry that much about being shot down anyway. Military UAVs are not terribly useful flying over your own territory. The military would want to fly them over enemy territory for information gathering, air strikes, and etc. UAVs are fine in places like Afghanistan were the terrorists are too unsophisticated to take them out. However like I said before any fighter jet or SAM can easily take out a UAV. Many countries and all the worlds major countries have this technology, including potential adversaries like North Korea. Satellite killing technology on the other hand is only available to a very few countries.

For a positioning system a moving UAV would be undesirable. GPS works because the GPS satellites are in Geosynchronous orbit

GPS sats are not geostationary. That is why they need so much sats to cover the whole world, there have to be at least 4 above any point at any time :shock:
http://en.wikipedia.org/wiki/Global_Positioning_System

A UAV platform can use ground beacons to adjust it's signal according to it's current position. It is much more efficient than a constellation of passing satellites; because it is always there you only need one to cover a diameter of about 1,000km. :idea: To cover the whole of the USA, you would need about 15 low cost platforms.

First of all its called Global Positioning System because it is global. That is what the military wanted when they designed it. That is why it is useful for ships, airplanes, missiles, UAVs, and etc. All these things travel across the ocean and between countries.

Second of all if you intention is to build a local positioning system than why use UAVs at all. The old LORAN system used radio towers, and it provided a decent positioning system for ships around the US for many years.

Lastly where are these UAVs going to get the power to transmit a powerful GPS signal at night. Current solar UAVs can hardly keep themselves in the sky at night let alone broadcast a powerful signal.

Telecommunication satellites often have the mass and size of a large SUV.

Because they need to operate for years in GEO they require large power sources, thruster rockets and propellant, spinning wheels for orientation, High-power antennas to cover the large distance (included the whole of the atmosphere). A UAV can be built much lighter :idea:

So a UAV would not the basic spacecraft subsystems like thrusters, propellant, gyros, and etc. However they would require the basic airplane subsystems such as motors, an airframe, actuators, and landing gear. On top of that a solar UAV would have to collect far more solar power than a satellite as it would need a substantial amount of power just to keep the aircraft in the air on top of powering the signal. On top of that to enable night operation you would need tones of batteries.

 

[PistolPete037]

Because they need to operate for years in GEO they require large power sources, thruster rockets and propellant, spinning wheels for orientation, High-power antennas to cover the large distance (included the whole of the atmosphere). A UAV can be built much lighter :idea:

No, the reason that they are so big is because the communications relay equipment requires a huge amount of electricity. Even though today's electronics require less power, more demand is being placed on comm sats for bandwidth, meaning that at the end of the day the size of the sats remains the same (the power requirements and size exponentially decrease, while the bandwidth demands exponentially increase, leaving a net change in size and power requirements of zero). These solar powered UAVs have barely enough power to keep themselves up, let alone enough to power the relay equipment.

And no, you cannot build a UAV much lighter. You need wings, a fuselage, heavy LiIon batteries, heavy power consuming electric motors, landing gear ect. A satellite just needs to float, collect solar electricity, occasionally make some sort of attitude correction, and relay a metric crap-tonne of data. It does not have to carry components that are not directly related to comms relay, station keeping, or power generation.

 

[PistolPete037]

If it had a months duty and returned for maintenance and crew charge it might make a lot of sense. As it matures duty can be extended.

Crew change? What page are you on? We're talking about UAVs over here.

 

[PistolPete037]

Why would the military fly a UAV over its own territory. The whole reason to use a UAV is to fly it over enemy territory

UAV is not always military. You can monitor crops, forest fires, storm damage, data relay, highway traffic control, oil plumes, weather, etc. All these things that are now done with satellites in LEO or GEO.
Such a platform 20km above for instance Chicago would be safe from all enemies, also terrorists. Portable missiles can't go more than 2km up. And fighter jets would be difficult to infiltrate.

Non-military UAVs do not have to worry that much about being shot down anyway. Military UAVs are not terribly useful flying over your own territory. The military would want to fly them over enemy territory for information gathering, air strikes, and etc. UAVs are fine in places like Afghanistan were the terrorists are too unsophisticated to take them out. However like I said before any fighter jet or SAM can easily take out a UAV. Many countries and all the worlds major countries have this technology, including potential adversaries like North Korea. Satellite killing technology on the other hand is only available to a very few countries.

I flew UAVs over domestic airspace all of the time. They are extremely useful in search and rescue missions. If they can find terrorists hiding in mountains, they can find people standing on their flooded rooftops trying to be found.

 

[scottb50]

If it had a months duty and returned for maintenance and crew charge it might make a lot of sense. As it matures duty can be extended.

Crew change? What page are you on? We're talking about UAVs over here.

I was talking about a LTA that uses Helium cooling and heating and electric motors for mobility and station keeping.

 

[MeteorWayne]

I flew UAVs over domestic airspace all of the time. They are extremely useful in search and rescue missions. If they can find terrorists hiding in mountains, they can find people standing on their flooded rooftops trying to be found.

I don't understand how that relates to the subject of this discussion. Sorry...

 

[PistolPete037]

I flew UAVs over domestic airspace all of the time. They are extremely useful in search and rescue missions. If they can find terrorists hiding in mountains, they can find people standing on their flooded rooftops trying to be found.

I don't understand how that relates to the subject of this discussion. Sorry...

To clarify, I was responding to this comment:

Military UAVs are not terribly useful flying over your own territory. The military would want to fly them over enemy territory for information gathering, air strikes, and etc.

I'm just saying that there are plenty of reasons why a military (not just the US military) might want to recon its own territory.

 

[PistolPete037]

I was talking about a LTA that uses Helium cooling and heating and electric motors for mobility and station keeping.

There is no reason that the LTA cannot be unmanned. In fact, an LTA that can stay aloft for months at a time makes for a strong case for it being unmanned.

 

[neilsox]

Upper atmosphere winds are as fast as 200 miles per hour, so solar power would loose ground trying to stay over the same city. We could launch 2 or 3 daily on the USA West coast and recover two or three daily on the USA East coast. With good luck, a few might be used for a month. Rather than ship them back to the West coast, they could be tethered at about 15,000 feet to replace cell phone towers near the East coast. The weight of the tether much reduces the maximum altitude.
Canada and Mexico would occasionally get to use one that strayed across the boarders. Gaps in service would be rare near the center of USA (and West of the center if the launches are widely distributed) with perhaps 50 moving across the USA, on the average, in a random pattern. Since each can relay data over a 300,000 square mile area = one large state, they could replace 1/4 of the GEO stationary channels. They would not be useful at sea more than a few hundred miles off shore, unless the data was relayed one or more times. The range should be more than 1000 miles from one UVA = unmanned aerial vehicle to another, but simultaneous relay and surface needs 4 antennas instead of two, or lots more transmitting power. Recovery would be spotty at sea, and most would fail before they reached Europe or Africa, starting from the USA West coast. There would be significant liability from the rare crashes into people's homes etc.
Months at a time seems optimistic for LTA = lighter than air. What is the present flight duration record? LTA can only move up wind at very low wind speed, but large antennas are less of a problem for LTA. If small antennas are used cross talk is a problem for 50 UAVs. Lasers and microwaves may be practical soon, but the laser transmitting and receiving arrays are almost as large and mostly blocked by thick clouds. Neil