Dr. John Jurist Webinar, Sunday, 4-26-15 April 25, 2015Posted by The Space Show in Uncategorized.
Tags: " SpaceX, 2 stage vs. single stage, amateur rocketry, Atlas missile, basic rocket equation., BLE, Considerations in configuring launch systems, Dietrich Koelle, Dr. John Jurist, environmental issues, exhaust velocity, Falcon Heavy, gravity load, gravity loss, heavy lift, human payloads, hybrid fuel, ISP, LEO, liquids vs. solids, mass, mass ratio, NERVA, nuclear propulsion, payload shrouds, payloads, pressure fed systems, rocket fuel choices, Skylon, SLS, suborbital point to point transportation, turbo umps, ULA, vibration envelope
Dr. John Jurist Webinar, Sunday, 4-26-15
Selecting The Rocket Motor, Fuel, & Trade To Optimize The Mission
https://vimeo.com/126223310– Webinar video
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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, https://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 www.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. TO VIEW THE WEBINAR VERSION OFTHIS PROGRAM, GO TO https://vimeo.com/126223310. 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.
Dr. James (Jim) Wertz, Monday, 2-11-13 February 12, 2013Posted by The Space Show in Uncategorized.
Tags: " SpaceX, advanced technology propulsion design, AMSAT, Cassini Resource Exchange, cubesat launcher, cubesats, Dr. James Wertz, drones, interplanetary missions, ISS, launch vehicle reusability, low cost space launch systems, Microcosm, military disaggregation, NASA, on orbit servicing, orbiting fuel depots, orbits, pressure fed systems, Reinventing Space, Reinventing Space Conference, Scorpius launch vehicle, sequestration, SmallSat., space debris, space mission planning, SSP, Surrey Satellite, Trading on Requirements, turbo pump, USC Astronautics
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Dr. James (Jim) Wertz, Monday, 2-11-13
Guest: Dr. James (Jim) Wertz: Topics: Methods for dramatically reducing space mission costs, schedules, & launches. Please direct all comments and questions regarding Space Show programs/guest(s) to the Space Show blog, https://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.
We welcomed Dr. Jim Wertz, President of Microcosm, back to the show to discuss various methods & tools for reducing total space mission costs. Our guest talked about successful programs and tools that have so far contributed to total mission cost reduction. In the first segment of our 1 hour 33 minute program, Dr. Wertz started by defining what he meant by reinventing space. He said this refers to a dramatic reduction in total space mission costs by a factor of 2::10 for schedule related reductions and 2-5 times for space access related costs. Early on he was asked about reducing costs by increasing the launch rate, a common argument heard in various sectors of the space industry. His response might surprise you. Dr. Wertz cited examples to support his comments, specifically Surrey Satellite in the UK (SSTL) as they have been reducing costs successfully for 25 years. He said modern technology must be used. He also pointed us to his Reinventing Space Project with the USC Astronautics Department. Also, he pointed us to these websites for more information, www.smad.com/ie/ieframessr2.html and www.smad.com/ReinventingSpace.html. Dr. Wertz mentioned disaggregation regarding the military using smaller spacecraft and different orbits. He was asked about cubesats and cubesat launchers, the Scorpius launch vehicle, and NanoEye. Jim offered sequestration and budgetary comments and pointed out the difficulty in mission planning and more when the nation continues to operate on CR rather than a budget. He talked about the potential seriousness of the sequestration cuts. In response to questions about the private sector and SAA type agreements, he pointed out that they exclude the smaller, more creative and innovative cutting edge companies as they are often unable to contribute the required financial portion of the agreement. Jim pointed out that the goal was to reduce total mission costs, not just launch costs. He said that the launch cost was not always the most costly component of the mission. As the segment ended, he talked about emergency response and the need for a rapid response, something that is today unavailable.
In the second segment, we talked about the Cassini Resource Exchange as an effective policy that reduced mission costs and enabled an on time project. Don’t miss the details about this program. He again talked about SSTL and pointed out that their attitude is what makes them special & so good. SSTL has pride in reducing mission costs. We don’t have such pride. Dr. Wertz talked about Trading on Requirements and why it is risky. During the first segment, fuel depots were offered up as a possible way to reduce mission costs but Dr. Wertz put them in the marginal category. During this segment, listeners had lots of questions about fuel depots. In fact, it was as if they cared more about their vision and beliefs regarding fuel depots than the overall message Dr. Wertz was putting out. Clearly fuel depots have the attention of space enthusiasts & sectors of the industry no matter what. A listener also asked about advanced propulsion concepts as represented by several companies pushing very advanced designs. Dr. Wertz mentioned that the amateur satellite network could be used to reduce mission costs and talked about the success of AMSAT. More listener questions came in regarding fuel depots, by far the most common discussion and question topic of the day. Jim talked about future programs that may offer economies of scale such as SSP. The last questions came in from Tim regarding our discussion of using pressure fed systems over the use of systems with a turbo pump. He also wanted to know about rocket reusability. Jim’s answers may again surprise you.
Please post your comments/questions on The Space Show blog above. You can email Dr. Wertz through me using firstname.lastname@example.org.