Quote from: bearshrimp on 04/11/2012 08:57 pm Given that there were 23 total launches of commercial LEO payloads in 2010 (per the FAA’s 2010 Commercial Space Transportation Review), and that projected growth is 8%....However, if we assume SKYLON came on line in 2022 (10 year gestation period) the demand for LEO payloads would only justify 40 launches in the 1st year of operation given an 8% growth rate. Over a 10 year period, given a growth rate of 8%, a total of 554 payloads would be available for transport to LEO. Two thirds of the commercial launches were to GTO not LEO in 2010 which you've failed to take account of in your extrapolation. Skylon addresses GEO either through the Skylon Upper Stage or the Fluyt OTV. Every Fluyt mission takes 5.2 Skylon launches, I believe. So if half the GEO launches are large enough to require a Fluyt then that's 1331 Skylon launches over 10 years, or an average of 133 launches a year by your numbers or nearly twice the 70 flights a year REL use as their baseline.
Given that there were 23 total launches of commercial LEO payloads in 2010 (per the FAA’s 2010 Commercial Space Transportation Review), and that projected growth is 8%....However, if we assume SKYLON came on line in 2022 (10 year gestation period) the demand for LEO payloads would only justify 40 launches in the 1st year of operation given an 8% growth rate. Over a 10 year period, given a growth rate of 8%, a total of 554 payloads would be available for transport to LEO.
The current Skylon baseline is the D4, which has 20tonnes to LEO. they specifically increased it's size because they needed to address the 4.6mx14m payload envelope and needed the 20 tonnes to have the necessary GTO performance. Not unlike the Shuttle's IUS.
Here is a consideration that I haven't seen raised for Skylon costs before, and I for one have no idea of its potential impact on Skylon launch prices. I wonder if anyone has a more quantitative notion.Skylon, being horizontal take-off, has, at least in principle, anytime-abort. Granted that with a take-off speed of around 0.5 Mach, the abort options may be few.So what does this do for insurance rates? These are a sizable fraction of current launch costs. Might Skylon's abort advantages lower insurance rates and therefore also contribute to lower total cost to orbit?
Of course SpaceX are claiming even lower long term figures for (a) re-usable launcher(s), but whilst that too is an amazing prospect, SpaceX seem to me much less concerned about being conservative in their presentation of the future!
Skylon will behave more like an aircraft. That means that the reliability should be on the 99.999%s or better. Particularly, it would allow for a type certificate process, which requires something like 100 flights. It's obviously not applicable to a disposable LV, but for the Skylon it might be reasonable. If we assume three crafts (800M x 3) plus 100 flights (say, 9M x 100), that's a 3.3B cost. But you could then use the crafts with some refurbishment. And your insurance costs would be really low.To get an idea, current F9 is about 15%, Ariane 5 is lower than 10%. A reusable Skylon should be much, but much lower. In fact, it they can get 99.99%, insurance costs should be close to 0.05%.
Quote from: baldusi on 04/12/2012 06:53 pmSkylon will behave more like an aircraft. That means that the reliability should be on the 99.999%s or better. Particularly, it would allow for a type certificate process, which requires something like 100 flights. It's obviously not applicable to a disposable LV, but for the Skylon it might be reasonable. If we assume three crafts (800M x 3) plus 100 flights (say, 9M x 100), that's a 3.3B cost. But you could then use the crafts with some refurbishment. And your insurance costs would be really low.To get an idea, current F9 is about 15%, Ariane 5 is lower than 10%. A reusable Skylon should be much, but much lower. In fact, it they can get 99.99%, insurance costs should be close to 0.05%.I don’t think that’s a great analogy, the SKYLON is predicted to have an expected life of 200 cycles. Per section 410 of the FAA regs (1.410(a)(1)(i) CFR14) the duty cycle of an Airbus A300 is 36,000 cycles. While 200 cycles is much better than one (disposable rockets) it still is far away from the expected duty cycle of a commercial airliner.
Quote from: lkm on 04/12/2012 12:38 pmQuote from: bearshrimp on 04/11/2012 08:57 pm Given that there were 23 total launches of commercial LEO payloads in 2010 (per the FAA’s 2010 Commercial Space Transportation Review), and that projected growth is 8%....However, if we assume SKYLON came on line in 2022 (10 year gestation period) the demand for LEO payloads would only justify 40 launches in the 1st year of operation given an 8% growth rate. Over a 10 year period, given a growth rate of 8%, a total of 554 payloads would be available for transport to LEO. Two thirds of the commercial launches were to GTO not LEO in 2010 which you've failed to take account of in your extrapolation. Skylon addresses GEO either through the Skylon Upper Stage or the Fluyt OTV. Every Fluyt mission takes 5.2 Skylon launches, I believe. So if half the GEO launches are large enough to require a Fluyt then that's 1331 Skylon launches over 10 years, or an average of 133 launches a year by your numbers or nearly twice the 70 flights a year REL use as their baseline.Yes, I know that the majority of missions are to GTO rather than LEO, but I haven’t seen any cost projections regarding the Skylon Upper Stage or the Fluyt OTV so I did not include them in my analysis. The ESA had the following statement on page 17 of the Assessment: “One point to be made is that ESA considers that the SKYLON Upper Stage (SUS) which is potentially required for GTO missions may need to be included in the overall development costs. This is because if telecoms spacecraft customers have to pay to develop a GTO stage on top of the launch price then this may push the cost to orbit to a point where the SKYLON becomes less competitive. ESA recommends that the development cost model of the vehicle be re-assessed to account for the additional cost of developing the SUS.”So, it’s difficult to estimate the cost to GTO provided by Skylon when compared to other launch systems. In a way my earlier estimate was probably optimistic in that only 33 payloads delivered to any orbit in 2010 were commercial. So if we assume that SKYLON will be responsible for delivering all commercial payloads to orbit, and the market expands 8% per year. The total number of commercial launches to any orbit would be 73 in 2022 rising to 150 in 2032. The total number of commercial launches would be 1,176. Assuming each SKYLON would be able to deliver 200 payloads over its 10 year service life that means that there would be a market able to support 6 SKYLON spaceplanes.The issue is still that in the economic analysis the development costs are amortized over 30 SKYLON craft. I just don’t see that kind of market demand. In a way it’s a catch-22. To bring down the operation and manufacturing cost on a per launch basis each SKYLON needs to be capable of performing a large number of missions. On the other hand, the ability to have each SKYLON perform a large number of missions will reduce the number required to satisfy the market. This in tern leads to a smaller number of SKYLONs constructed and increases the amortized development cost on a “per vehicle” basis.To justify a production run of 30 SKYLONs between now and 2032 the demand for commercial launches would need to increase an average of 17.7% per year. I think we would only see double digit growth in the commercial space sector if there were considerably more money to be made in orbit. Perhaps if the Japanese really do develop their 1GW orbital power station (requiring between 300-400 orbital trips) Skylon would find its market, but that’s a big if.
One point to be made is that ESA considers that the SKYLON Upper Stage (SUS) which is potentially required for GTO missions may need to be included in the overall development costs. This is because if telecoms spacecraft customers have to pay to develop a GTO stage on top of the launch price then this may push the cost to orbit to a point where the SKYLON becomes less competitive. ESA recommends that the development cost model of the vehicle be re-assessed to account for the additional cost of developing the SUS.
Yes, but the Falcon and Falcon-9 have flown and you can go out and contract with SpaceX to put your satellite into orbit. Right now they are booked until 2013 I believe. Given that they are already operating at budget, I tend to lend more credence to their statements than those made by companies still 10 years out from a viable product.Oh, BTW I am not a SpaceX plant I just noticed that a lot of my posts sound like a cheering section for SpaceX.
http://www.rinkworks.com/said/predictions.shtml
Given an 8% annual growth rate, here are the number of commercial launches one may reasonably expect annually. Note that with a duty cycle of at least 200 missions over a 10 year period and a 48 hour turnaround time, there would be little need to ever have more than 2 or 3 SKYLONs operating at any given time. Even if you assume competing vendors offering services I just don’t see the market for 30 SKYLONs. ....If there were say 6 Skylons operational in 2025, they would be substantially underutilized. The ESA Analysis states that operating costs are based on 70 missions per year per SKYLON.
I want to make sure everyone knows what they are getting into this time. The shuttle was truly traumatic in that the claims of cost efficiency in the 70’s are basically the same as those being made for SKYLON today.
The easiest way to get launch costs down to $100/kg is just to have the government pay the other $9900/kg.
Does anyone know where I can find the “SKYLON System requirement Review: SKYLON Commercial Operation, Alan Bond, Reaction Engines Ltd” listed as RD2 in the ESA Assessment?I would like to take a look at the actual ROI numbers provided by REL. Not that I need to be satisfied for SKYLON to happen , but if I can see a reasonable argument where SKYLON will be able to achieve a LEO cost to orbit of $1M per mt (i.e. $1000/kg) then I will be more enthusiastic. To get really excited about a new orbital interface system I would like to see a cost to LEO of $500/kg, now that IMHO would trigger a true commercial space race. Even if the development costs are subsidized I would like to see an analysis of how we can get to $500/kg within the next 25 years.