Lesson 13 Archive Notes September 24, 2010Posted by drspaceshow in Uncategorized.
Space Show Classroom Lesson 13: Orbital Propellant Depots
Thursday, Septembeer 23, 2010
Archive Notes and Program Information
The Space Show Classroom Lesson 13 can be downloaded or heard
Guests: Classroom featuring Dr. David Livingston, Dr. John Jurist, Dr. Jim Logan and Dan Adamo, Dallas Bienhoff. Topic: Orbital Propellant Depot. Welcome back to this Classroom program focusing on an intense and comprehensive 2 hour 25 minute two segment program. Please note that as with all Classroom programs, your emails and comments are to be posted on The Classroom Blog at https://spaceshowclassroom.wordpress.com once this program is archived as the Lesson 13 Archived Program. I also want to point out that there were significant telephone line and audio issues on the lines with some of our expert panel members and I apologize in advance for less than perfect audio conditions. This was a comprehensive and detailed discussion on the pros and cons of orbital propellant depots, the places to put them, economics, launches, constraints, regulations, and much more. In our opening segment, Dallas started out by talking about the reference study, comments made by Dr. Mike Griffin as the NASA Administrator regarding the value of fuel in a depot to NASA and more. Dan followed with some of the orbital constraints involved along with operational logistical issues. At times this was a technical discussion but one that I believe everyone should hear and pay attention to because the discussion with Dallas and Dan along with the co-hosts was at a very high level and all of us learned a lot during this program. Some of the issues we talked about during this segment included loitering on orbit for perhaps up to a week using the Orion and Altair. You will hear why this is so and why the system was not capable of landing any where any time. We talked about LEO depots, concerns and trajectory constraints. Dan talked about Plain of Regression which is 7 degrees west and what this means for depot placement, Delta V, and ingress egress. Dallas said that their study only looked at the Moon and never looked at other destinations. The study he referenced was for back and forth to the Moon using L1. Other topics addressed launch rates and the number of launches required to put a specific mass on the Moon using the depot as compared to using a heavy lift rocket. The issue of divorcing a commercially operated depot from existing federal regulations was a hot topic in both segments with Dallas offering one view and Dan looking at the problem from a different perspective given his operational experience, specifically with the Eastern ranges. The second segment started with our discussing docking with Dan pointing out why docking was risky and problem oriented, and Dallas talking about how we can and will use docking with the depots. Dallas was also clear that the depot was not a replacement for heavy lift but an enhancement of capability for all launchers, including heavy lift. Later, when our guests were asked for their ideal programs, were we to be starting out with a fresh slate, no legacy anything, one would designs systems for specific environments and as Dallas said, you might not need heavy lift but that is not the world we live in today. Launch and propellant economics and the business case for a depot came up during this segment. Our co-hosts had many questions, we talked about cryogenic fuel boilff, power to the depot, and lots more issues. Dallas outlined how its thought that the boiloff can be used to station keep the depot. Other topics that were addressed were civil space traffic control, collision avoidance, Bigelow Aerospace as a customer, developing markets and customers, and the size needed for a heavy lift rocket. Numerous other topics and issues were discussed by our experts and co-hosts during this program. Remember to post your comments and questions on the blog. Please do not send tem to me but if you do, I will post them on the blog under your name.