Guest: Dr. John Jurist. Topics: Choices and consideration in configuring launch systems. Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, thespaceshow.wordpress.com. Comments and questions should be relevant to the specific Space Show program. Written Transcripts of Space Show programs are a violation of our copyright and are not permitted without prior written consent, even if for your own use. We do not permit the commercial use of Space Show programs or any part thereof, nor do we permit editing, YouTube clips, or clips placed on other private channels & websites. Space Show programs can be quoted, but the quote must be cited or referenced using the proper citation format. Contact The Space Show for further information. In addition, please remember that your Amazon purchases can help support The Space Show/OGLF. See onegiantleapfoundation.org/amazon.htm. For those listening to archives using live365.com and rating the programs, please email me as to why you assign a specific rating to the show. This will help me bring better programming to the audience. Welcome to this two hour webinar regarding the choices and considerations that can be made in designing and configuring launch systems. Note that on the blog for this program are two Power Point presentations for your use. Dr. Jurist referred to both of them during the webinar, especially the presentation titled "Choices: Some Considerations in Configuring Launch Systems." I urge you to follow along with them during the webinar. During the first segment, Dr. Jurist explained the target market for the webinar and his two presentations. He then talked about how hard it was to go to Mars and do other missions. Then he got to the point by saying in designing or configuring the launch system for a mission, you started with the payload requirements which then provide additional constraints once the payload has been defined. He also talked about the application of the basic rocket equation and explained the importance of exhaust velocity, the Delta-v, and the mass ratio. Listeners started asking questions so two stage compared to single stage was discussed. John pointed to the Choices presentation, slide 8. He talked about propellant and pressures, both in a pressure fed system and with a turbo pump system. Another listener asked about solids versus liquids, then Marshall called to talk about rocket g forces. Dr. Jurist talked about designing the rocket envelope environment to the payload specifications. He then brought in and discussed the vibration envelope. Helen asked how things would be different with a human payload rather than a satellite or cargo. Reliability was a big concern. Near the end of the segment, Dr. Jurist talked about payload mass in Leo and BLEO. Doug inquired about the gravity loss during the launch, then the segment ended talking about heavy lift, solids and proportional cost factors for SRBs. In the second segment, Penny asked how the variable that had been discussed would change were one launch from the Moon or Mars. Adrian emailed in about the NERVA rocket and nuclear propulsion. Dr. Jurist used the German V2 as an example of launching from the Moon. Specific impulse and exhaust velocity came up again, then the focus turned to rocket motor cooling systems. Questions continued coming in asking about 3D printing of rocket motor parts to lower the cost and the use of hybrid rocket fuels with their advantages and disadvantages. Regulatory issues came up in this segment as did political issues, plus our guest got a question about amateur rocketry. A listener asked about environmental concerns over rocket fuel. Dr. Jurist directed the audience to the Choice presentation, slide 22, and talked about ways to possibly shed some weight such as dumping the payload shroud. Near the end, John got questions about the Falcon Heavy, Doug called in with questions about lunar lander economics and more. In closing, Dr. Jurist said "the fundamental theme of the presentation was the many variables that come into play in designing or configuring a space launch system, how the many variables are inter-related, and how every decision in the process constrains or narrows the remaining options." Please post your comments/questions on The Space Show blog above. You can contact Dr. Jurist through me.