I’m traveling for several weeks, so posts will be erratic. Fortunately, this appears to be a slow time for news on future planetary missions and roadmaps. One consequence of traveling is that I sometimes won’t be able to easily look up URLs to my source material. My apologies.
Today, I have two tidbits. First, Keith Cowling at NASAWatch has posted a list of schedule changes to NASA science missions in the past year. The list of schedule changes for planetary missions is fairly long:
Curiosity (MSL) rover: slipped from 2009 to 2011
LDCM: slipped from 2011 to 2012
LADEE: slipped from 2011 to 2012
ILN (International lunar network): slipped from 2013 to 2018
Solar Probe: slipped from 2015 to 2018
Mars Sample Return: slipped from 2018 to 2022 (or later)
Editorial thoughts: Cowling says that the schedule slips are because of , “These slips are related to cost overruns that SMD is unable and/or unwilling to contain.” Cost overruns are certainly happening, but I think that the science division is also being run more conservatively. If you bet that shit will happen, you are less aggressive on your schedules. Some of the missions were so early in their definition (e.g., ILN and Solar Probe) that their schedules were place holders rather than firm commitments. And the schedule for the Mars sample return wasn’t credible before and, in my opinion still isn’t credible.
In a related note, the Decadal Survey has released a request for information as an early step to findr a company to provide independent cost assessments for proposed missions. According the RFP,
“The National Research Council (NRC), under sponsorship of the National Aeronautics and Space Administration (NASA) and the National Science Foundation (NSF), has established the Planetary Science Decadal Survey Committee (the Survey Committee)—consisting of a Steering Group and five supporting panels—to conduct the Planetary Science Decadal Survey (the Survey)to assess the key scientific questions for the field over the next decade and to identify the priority investments in spacecraft missions that will enable the field to address those questions (see Attachment B for the Survey Committee’s statement of task). To support this goal, the NRC intends to contract with an independent organization to estimate the cost of potential spacecraft missions to various destinations in the solar system. These cost estimates will be an input to the committee’s overall prioritization process.”
“The contractor shall perform objective, independent estimates of cost, risk and schedule for the various mission concepts which may be at significantly different levels of definition and development maturity. The technical data describing the mission concepts will be coming from several different institutions and/or individuals. The Survey Committee will not uncritically accept estimates provided by project proponents or responsible agencies. It is anticipated that, on the basis of the technical readiness assessment, the Survey Committee may decide that some activities may take the form of high-priority technology development programs rather than projects.”
“The contractor shall develop a series of top level quad-charts for each activity concept using four “quad” panels: a) activity description including technology development requirements, b) cost and schedule estimates, c) funding profile, and d) technology readiness and risk rating. The contractor shall also provide an “S-curve” that is generated by the cost model on a separate chart for the committee’s consideration. The quad-charts will provide a top-level snapshot of each concept for summary purposes and an overview of its merits, issues, and expected budgeting requirements. All information provided in the quad-charts is to be backed by additional analysis, provided to the committee by the contractor.”
Editorial Thoughts: I believe that independent cost and risk assessments are absolutely essential to develop a credible Decadal plan. However, I’ve been involved in a number of cost and schedule estimation exercises (for a leading high tech firm). If my experience there is any guide, this Decadal Survey will have more accurate cost and schedule estimates than the last, but the costs and schedules for at least some of the priority missions will still be low. Assuming that is the case, it would be valuable for the Survey to provide a descope plan to decide up front which missions will either be cancelled or will not be started as cost overruns occur.
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