Gert van Ommering, Director of Technology at Space Systems/Loral – and leader of the company’s activities regarding COTS 2 – has conducted a Q&A with NASASpaceFlight.com.
SS/L and Constellation Service International (CSI) have collaborated to bid for the lucrative NASA contract, utilizing SS/L’s 1300 model spacecraft bus and CSI’s space intermodal transportation architecture.
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A) The tug does approach the station with the container forward. Our trades favored that to minimize thruster plumes constraining ISS and lidar operations and to avoid reorientation at the ISS just prior to berthing.
If you look closely at our fact sheet you can see that the tug has two deployed booms that carry the lidars and the space-to-space S-band antennas. This way the lidars get a large enough view of the station to accurately determine range, position and attitude for a safe approach and hold.
Q) Is the lidar system eye-safe? (Class 1, 2, or 3R), or will there need to be restrictions placed on crew activities near the windows during prox ops? If the latter, how will that affect SSRMS operations?
A) We have baselined the XSS-11 Flight Lidar from MacDonald-Dettwiler which uses a Class 3B laser which is not eye-safe without some precautions. We have a filter on the return path but not on the forward path as would be required for eye safety.
Q) Is the tug GN&C system capable of LVLH attitude hold? If not, how does that affect the SSRMS capture window?
A) Yes, our GN&C system is designed for the LVLH hold capability. With the lidars and the S-band systems we can accurately determine range and rate relative to the ISS.
Q) When and how are the biprop thrusters inhibited during the SSRMS capture process? The thrusters appear to be too small to present a plume overpressure hazard, but how about contamination?
A) We inhibit the 455-N biprop thrusters several kilometers out – those are only used for orbit transfer. We use the 22-N biprop thrusters to maneuver to a few hundred meters from the ISS, then we inhibit those. From there on we are on cold gas only. So we’re very careful to avoid contamination risk.
A) Yes, we’re providing the same capability as HTV. Our team member, MDA, will provide the same S-band communication system that it has built for HTV, which gives the ISS crew a Visiting Vehicle telemetry & command link.
MDA will specify a new video overlay for the ISS Robotic Workstation monitors for crew situational awareness during approach and departure. The overlays showing the Tug’s relative position data will be matched to ISS or SSRMS camera views and will allow the ISS crew to ‘mirror’ the Tug’s GN&C data. This allows the crew to monitor the tug and execute an abort if they judge that is needed.
Q) Do you have your financing in place for your COTS?
A) We are not going to publicly talk about specific financing alternatives, but I can tell you that I am confident about financing this venture. For one thing, the business case looks strong at cargo delivery prices that are win-win for both NASA and us. And our company’s historical ability to arrange financing for similar and larger magnitude commercial space ventures speaks for itself.
Q) How do investors feel about NASA’s historic unreliability as a partner in these types of deals?
A) We believe that there is a commitment at the highest levels in NASA to see COTS through to operational capability. But, of course, changing circumstances, unforeseen events and politics can impact what ultimately happens.
So we think it’s unreasonable to expect investors to make commitments until we have an ISS cargo supply services contract in hand, including some protection against the demand going away altogether. That will take the most significant uncertainty out of the picture.
It’s important to realize that this will be a commercial business. Investors in this kind of business aren’t in it for the space gee-whiz, but primarily for the financial returns. And for that to work you need to bound and manage your risks. Our experience in commercial space pointed us to our low-risk technical and business approach, and will allow us to partner with NASA in a viable, win-win relationship.
Q) Do you have a financial risk mitigation plan in place for your investors in case NASA decides to go another direction in regards to commercial cargo flights?
A) I covered that to some degree in the previous answer. By the time the investors are asked to firmly commit their funds, NASA will have awarded an ISS cargo services contract with appropriate price structures and safeguards against the risk of these services going away. It is equivalent to a manufacturer providing vendor financing of a unique custom product for a customer – we do that on occasion.
If that customer then changed his business plan and no longer wanted the product, the manufacturer would have recourse to recover the investment.
Q) How large could a piece of external cargo be? Could it, say, be the size of the cargo container (~7000 kg)?
A) The tug can carry a piece of external cargo with a mass of 10 tons and possibly more. One constraint is that it must have an interface compatible with the tug docking system, or at least accommodate some sort of adapter that makes it compatible. That interface should be accessible when the cargo item is still attached to its launch vehicle upper stage and it should be located so that that the overall CG is in a reasonable position when the cargo item is attached to the tug.
Maybe you are thinking of AMS-02, the Alpha Magnetic Spectrometer experiment, which is in need of a ride to the ISS. The nice thing about our intermodal COTS approach is that, so long as a cargo item has the right interface to dock with the tug, we can take it from its launch vehicle to the ISS.
That’s what is powerful about the intermodal approach with a big, refuelable space tug. It can transport all kinds of things. It can be replicated to serve a growing orbital infrastructure in other orbit planes. It can help assemble commercial space stations and other large commercial spacecraft in orbit.
So I think that an intermodal COTS system like ours has great potential to meet one of NASA’s Commercial Crew & Cargo Program objectives, which is to make investments to stimulate the commercial space industry.
A) Yes, there is commonality in concept between containers for the ISS cargo mission and containers for other space applications, such as human exploration of the Moon. CSI’s Lunar ExpressSM concept, in which a container expands the existing Soyuz spacecraft into a lunar exploration vehicle, is just one example. In that case, the container has Russian docking ports, while our COTS container uses the Common Berthing Mechanism.
A key benefit of standardized containers is that they can inexpensively add capabilities and flexibility to existing systems. We have seen how the use of standardized containers rapidly took hold around the world and helped transform the global economy by lowering the cost of cargo transportation. Similarly, containerization could help the United States to rapidly open up the Earth-Moon system.
Q) Have you discarded the Progress/cargo container approach in favor of the Tug/CC approach?
A) The Progress and Russian cargo container approach is not viable in the long term because NASA will not be able to use this after 2011 when its Iran-Syria Non-proliferation Act waiver runs out. But it could be used as an interim cargo solution before our all-US COTS approach is demonstrated in 2010 or early 2011.
Q) How important is COTS from your perspective? Do you believe it is a viable avenue for a company to take due to the serious problem of ISS supply post Shuttle in 2010 (may change)?
A) COTS is very important from my perspective for several reasons. One, the ISS is a major asset that needs this kind of service to keep it productive and to meet our international commitments. Second, it is smart to get relatively routine services done commercially and privately and allow NASA’s brainpower to focus on space science and new, cutting-edge exploration developments.
But as you are suggesting, the Government approach to ISS supply may change, and for some COTS contenders that could be a big impact. For SS/L, while COTS is an important business opportunity, it is only one of many we are pursuing.
As the world’s leading provider of high-power satellites we have a very strong business base. It’s that same business base and experience that should make us a very strong contender to win COTS.