1. Ground testing does not qualify "demonstrated" for flight operations2. Business arrangements that were never carried out do not qualify as proof.
Response to 2) Whether a business case closes was not the topic. You stated that "It is magnitudes greater." in response to a question about "the cost difference between refueling a sat and moving a sat to a graveyard orbit is likely not that great ...". Intelsat signed a contract with MDA for $280M to provide fuel to 5 existing satellites to extend their operational life by 5 years each. That contract was a legally binding agreement. Whether it was ultimately executed doesn't alter the value of the service being offered. That $280M contract was for 25 years of cumulative operation for an average of $11.2M per year/per sat. Intelsat generates between $50M and $100M in revenue per year per satellite or between $4M and $8M in revenue per month. Executing a graveyard maneuver consumes between 2-3 months of station-keeping fuel equating representing $8M - $24M in revenue potential. Thus refueling is not "orders of magnitude" greater cost than simply executing a GEO graveyard maneuver.
There was even a demonstration of a Coke machine transferring carbonated fluids
Quote from: Jim on 11/16/2013 04:03 pmQuote from: GuessWho on 11/16/2013 02:49 pm1. Yes, the technologies have been ground tested. At MDA and at NASA. NASA is flight testing those technologies on-orbit at ISS.2. No, it is not "magnitudes" greater. Graveyarding costs 2-3 months of effective satellite revenue thus on the order of $10-$12M in lost revenue. Prior business arrangement have shown that refueling is worth $10M-$12M per year of added life per satellite to an owner operator.1. Ground testing does not qualify "demonstrated" for flight operationsJim... haven't you seen the Robotic Refueling Mission videos? They've been testing it on orbit on ISS on simulated task boards. That may not be TRL 9 yet, but that should count for something, even to a skeptic, shouldn't it?Quote2. Business arrangements that were never carried out do not qualify as proof. While it is true that nobody has demonstrated the business case closes...isn't that true of even of successful business models before someone has made them work the first time? I agree there's room for *some* skepticism, particularly about timing and busines model closure at this point in time. But there's plenty of examples of technologies or business models that people thought of long before all the pieces were there to make them happen. Cars and heavier than air flight come to mind for instance.~Jon
Quote from: GuessWho on 11/16/2013 02:49 pm1. Yes, the technologies have been ground tested. At MDA and at NASA. NASA is flight testing those technologies on-orbit at ISS.2. No, it is not "magnitudes" greater. Graveyarding costs 2-3 months of effective satellite revenue thus on the order of $10-$12M in lost revenue. Prior business arrangement have shown that refueling is worth $10M-$12M per year of added life per satellite to an owner operator.1. Ground testing does not qualify "demonstrated" for flight operations
1. Yes, the technologies have been ground tested. At MDA and at NASA. NASA is flight testing those technologies on-orbit at ISS.2. No, it is not "magnitudes" greater. Graveyarding costs 2-3 months of effective satellite revenue thus on the order of $10-$12M in lost revenue. Prior business arrangement have shown that refueling is worth $10M-$12M per year of added life per satellite to an owner operator.
2. Business arrangements that were never carried out do not qualify as proof.
Response to 2) Whether a business case closes was not the topic. You stated that "It is magnitudes greater." in response to a question about "the cost difference between refueling a sat and moving a sat to a graveyard orbit is likely not that great ...". Intelsat signed a contract with MDA for $280M to provide fuel to 5 existing satellites to extend their operational life by 5 years each. That contract was a legally binding agreement. Whether it was ultimately executed doesn't alter the value of the service being offered. That $280M contract was for 25 years of cumulative operation for an average of $11.2M per year/per sat. Intelsat generates between $50M and $100M in revenue per year per satellite or between $4M and $8M in revenue per month. Executing a graveyard maneuver consumes between 2-3 months of station-keeping fuel equating representing $8M - $24M in revenue potential. Thus refueling is not "orders of magnitude" greater cost than simply executing a GEO graveyard maneuver. Learn before you post. Think before you respond.
SMM - MMU/TPAD would not engage. Ended up using RMS to grab spacecraft HS 376 retrieval - Handling frame would not engage, crew had to hold on to spacecraft by omni antennaIntelsat VI reboost - capture frame would not engage, 3 EVA crewmembers had to grab spacecraft.
Wait, what? What, in those numbers, actually represents the cost of refueling a satellite? None of it. That's what Intelsat was willing to pay, which of course is driven by their revenue numbers and alternative costs.
I'm not arguing for orders of magnitude difference in price, but in order for it to close right now, I suspect you'd need at least a half-dozen EOL satellites, with not too much deltaV separation between orbits, that can be refueled from one launch of your equipment. And it better happen reasonably quickly, too, because your debt costs money and your personnel can't wait a decade before a payout.
HS 376: The actual capture went extremely well and showed that a capture mechanism designed to engage via the apogee engine works quite well. Why you think failure of a storage device designed to hold the sat in the shuttle bay for return to earth constitutes a failure of on-orbit capture and servicing is beyond me.Intelsat VI reboost: And the lesson learned is not to design an overly complex solution to a simple problem. The whole cross-bar solution was a stupid one. Note that current approaches (DARPA OE, PHOENIX, MDA SIS) typically use one or more robotic arms with capture "hands" to capture the interface ring where an upper stage attaches. Surprisingly, exactly how the STS-49 crew ultimately captured Intelsat VI. Hardly a damning indictment of on-orbit servicing. More a case of applying lessons learned.
The issue isn't that on-orbit servicing or capture isn't feasible. It is that interfaces (i.e prop and pressurant fill and drain valves) not designed for onorbit servicing will be problematic.
Problematic doesn't mean there isn't a solution, GuessWho.
The issue I have is doing the refueling on spacecraft that were not design for it. Look at all the times NASA serviced a spacecraft that was not design for it, there were always dimensional problems and the crew had to do workarounds. SMM - MMU/TPAD would not engage. Ended up using RMS to grab spacecraft HS 376 retrieval - Handling frame would not engage, crew had to hold on to spacecraft by omni antennaIntelsat VI reboost - capture frame would not engage, 3 EVA crewmembers had to grab spacecraft.
Quote from: a_langwich on 11/17/2013 06:27 amWait, what? What, in those numbers, actually represents the cost of refueling a satellite? None of it. That's what Intelsat was willing to pay, which of course is driven by their revenue numbers and alternative costs. And what MDA set the price at which they were willing to contractually sell the service for. That price of course is driven by their business case which includes all of the costs you mentioned; i.e., what it costs to design and build the refueling satellite, the cost to launch the equipment, the amount of fuel it needs to reach client satellite, the fuel it uses to perform ARPO and capture, the amount of fuel it plans to load onto the disabled satellite, the ground infrastructure costs to execute the mission, the insurance costs, taxes, interest, etc. such that at the end of the day, they actually realize a profit.
Quote from: a_langwichI'm not arguing for orders of magnitude difference in price, but in order for it to close right now, I suspect you'd need at least a half-dozen EOL satellites, with not too much deltaV separation between orbits, that can be refueled from one launch of your equipment. And it better happen reasonably quickly, too, because your debt costs money and your personnel can't wait a decade before a payout.Jim did argue for "orders of magnitude difference" and seems unwilling to retract that statement. But that is not your point so let me respond. Intelsat and MDA signed a contract for 5 satellites (plus a sixth to be used as the initial demonstration of the refuel capability) so yes, you need a half-dozen or so clients signed up to even consider executing a business case. Rephasing from one sat to the next is not that delta-V intensive. It depends on how far apart they are on the belt and how quickly you want to perform the phasing maneuver. Given MDA was using an EP prop system to perform the phasing maneuvers, I suspect the timing was slow and the fuel use minimal. Also, if you read up on the MDA approach, they were designed to refuel twice the number of sats that Intelsat actually settled for. So presumably, MDA could refuel 10 satellites with a single servicer. And who is to say that they couldn't then refuel themselves and continue operating for several years?And from what I have gathered from several MDA presentations, they were expecting to launch within 3 years of signing the contract. Problem is, they couldn't sell the other 5 refuel missions they had capacity for so didn't execute the contract. Still doesn't alter the price that both the seller and the buyer were willing to pay for a refuel service which still isn't "orders of magnitude" greater than simply graveyarding a satellite at EOL.
This gets back to what Jim said about not being validated. Unless you happened to work the numbers at MDA for the proposal, you can't assume that price included a profit or break-even. And it sounds like, even there, they HAD to have five other servicings to make the business case close. Do you know how much revenue they depended on the second five to bring in?
You keep bringing up this firm contract but it must have had some large holes that allowed them to walk away without executing it. This raises again the question of deltaV and/or market size--they found five in a plane, maybe, or energetically nearby, but didn't find ten. You say, "See: it was easy. They found five." I say, "They didn't find ten, which apparently they had to have to purchase a launch."
Maybe they exhausted all the possibilities within reach? Or maybe they realized they weren't going to get anywhere near their cost target for the vehicle? Or, maybe they realized the market demand was not enough to support not just their pricing but any reasonable price, at the present. Bottom line, you can't say it works at this price, when something clearly did NOT work.
All of this, oddly, ignores the risk of not being able to get it working on the first go, which is substantial I think.
At the bottom of page 2 of the "Economics of Repurposing in situ retired spacecraft components" paper assembly in space to build very large apertures for RF and optical systems is mentioned. This relates to something I had been wondering about lately. Taken to the extreme, might three huge antennas with appropriate electronics, built in GEO, be able to replace cell phone towers by allowing 2 way comm with existing cellphones directly? That would be what - a trillion dollar business?
Quote from: Solman on 10/22/2013 12:40 am At the bottom of page 2 of the "Economics of Repurposing in situ retired spacecraft components" paper assembly in space to build very large apertures for RF and optical systems is mentioned. This relates to something I had been wondering about lately. Taken to the extreme, might three huge antennas with appropriate electronics, built in GEO, be able to replace cell phone towers by allowing 2 way comm with existing cellphones directly? That would be what - a trillion dollar business? CELLULAR: Xerox Parc put it best in the late 80s and early 90s bandwidth / the population of earth = bits/sec per personThere are some 7 billion people on this world so that Tesla style solution doesn't work. with your 3 antennas canted to service 3 spherical triangles from on high and maybe covering 1/3 of the earth the best you get is: 1 cell size of 3 (antennas or sectors) * 3 sats to cover the earth *bandwidth/7 billion peopleYou want lots of cells... micro-cells in urban areas larger narrow long cells on transit routes (so you don't hand off so much - esp with things like high speed trains racing through cells... so you have long narrow cells on the tracks enabled with leaky coaxial cable the full length of the tracks) You want multi-spectrum, you want robustness in handoffs (hence the CDMA scheme with its soft and softer handoffs).
Since Xerox Parc didn't happen but was schematically the cleanest concept we can discuss their drivers without ruining functional IP in use today. Xerox Parc wanted to do it with a staged system with cheap cellphones. Theirs were not RF but IR. They envisioned fiber going street light to street light with IR LEDS and to/from IR cells and lasers or tight beam IR to the house with IR base stations all over inside your home or business. Your car would have had IR to your phone connected to a radio based cellphone in the car. The reason for that is if you had to hand off to each IR LED base station every 30 feet or so at auto speeds you would spend all your bandwidth handing off so you need to drop down in frequency to radio waves and take advantage of their greater cell size. This would allow using cells for rural and transit routes. Note how cheap this made cellphones. A basic one only needed the LED/Photo Transistor in your TV remote and electronic of similar complexity. They envisioned early 1990's costs of 50 cents a phone. Obviously we went a much more complex direction but the underlying system is trying to enable the same solution to the formula by making cell size very small
(time multiplicative factor {not allowing each user total time} * maximized cell count * maximize sectors per cells * max frequency per cell )/ (Population of earth * devices per individual ) It becomes obvious you don't want to go up to a few satellites except, possibly, for inter-regional backhaul in rural or remote areas. The next level up from doing it Xerox's way and retro fit what we had would have been to have micro cell sites in every cable tv box or DSL modem. That would have made the governments (all levels) in the USA very unhappy as they earn huge revenues on the large tariffs on backbone lines like T1s, E1s and higher speed currently required to service cell sites.
The IR light is unlicensed spectrum which would deprive governments of the billions of dollars received selling licensed spectrum.
The sneaker way to do it would be to hand off to WiFi when available. The Telcos and Government have revenue reasons not to make this a feature.
Cellular is the way it is currently for political reasons and at the beginning for the desire of manufacturers to sell Big-Iron multi-billion dollar infrastructure to Telcos.
Iridium and it's ilk have their niche as they have a multi-digit N sats and sectorization and time slots and large spectrum but it can never be a cellular system for the masses just one to serve remote areas and elites.
Quote from: watermod on 11/23/2013 03:21 amThe next level up from doing it Xerox's way and retro fit what we had would have been to have micro cell sites in every cable tv box or DSL modem. That would have made the governments (all levels) in the USA very unhappy as they earn huge revenues on the large tariffs on backbone lines like T1s, E1s and higher speed currently required to service cell sites.Sorry, but that's nonsense. Voice and data traffic through cable modems and DSL modems goes through exactly the same backbone lines.Anyway, there's no reason to believe the people making the telecom regulations care at all about how much revenue the government gets from it. It doesn't affect how much money their organizations get, it goes to general Treasury accounts. If Congress cared, they could as easily assess fees on IR systems, cable modems, whatever they wanted to.The carriers are the only ones who would care, and only to the extent it derives them of revenue. So the carriers could conceivably exert political pressure to get the government to tilt the rules against femptocells. But, there's no evidence they did. The government wasn't really involved one way or another. The carriers were slow to adopt it, and it wouldn't work on people's cell phones unless the carriers agreed, so the carriers made it more difficult. But recently some carriers have been moving in the direction of supporting femptocells.Quote from: watermod on 11/23/2013 03:21 amThe sneaker way to do it would be to hand off to WiFi when available. The Telcos and Government have revenue reasons not to make this a feature. Again, only the carriers (telco companies) have any incentive not to enable WiFi hand-off, not the government. And the carriers, while initially opposing WiFi hand-off have started moving in that direction recently, since they've realized most of their customers are on unlimited plans these days, so they don't get more money per minute of celluar use, so handing them off to WiFi doesn't decrease revenue at all but instead reduces costs because fewer calls go through the carrier's cellular network.
The next level up from doing it Xerox's way and retro fit what we had would have been to have micro cell sites in every cable tv box or DSL modem. That would have made the governments (all levels) in the USA very unhappy as they earn huge revenues on the large tariffs on backbone lines like T1s, E1s and higher speed currently required to service cell sites.