Mars Ascent Vehicle (MAV) Reaction Control System (RCS) 5N Thruster

6/24/2021 FYSA: 3. Proposal submissions in response to this solicitation shall be due no later than June 24, 2021 at 3 P.M. Central Time. The time for receipt of proposals in the MAV RCS Thruster solicitation in the table in provision, "MSFC 52.215-91 DUE DATE FOR RECEIPT OF PROPOSALS OR QUOTATIONS (SEP 2019)" was inadvertently not updated to reflect 3 P.M Central Time. ____________________________________________________________________________ 6/09/2021 FYSA: 1. Additional update to Section L includes a revision to - Volume III - Past Performance Volume Instructions (c)(3) stating the following, - Complexity - A referenced contract's complexity relevancy will be determined based on how well the complexity of the effort performed aligns with the effort delineated in Attachment J-1, production and delivery of monopropellant hydrazine thrusters of a different size qualified to similar environments, and management of a relevant program with similar cost and/or schedule. The document titled, "Amendment 1 Mars Ascent Vehicle (MAV) RCS Thruster Solicitation 09 June 2021" has been uploaded and updated to reflect these changes; and 2. The document titled, "Mars Ascent Vehicle (MAV) RCS Thruster Volume IV Model Contract" was erroneously omitted from the provided attachments and has been uploaded to this posting. Question 2: Specification 3.2.13.1, Figure 1, 2, and 3 define the thruster envelope and position within the vehicle. Are the thruster positions/dimensions outlined in the figures firm dimensions? For example, in Figure 2, is the - 1.875 to vehicle center-axis dimension a hard dimension, or can that dimension be increased to move the thruster closer to the OML? Answer to Q2: Yes, there is some room to reduce that dimension, although we don't currently have a defined minimum that we can provide. We will provide an update once this number is available. Question 3: Specification 3.3.3 mentions a gasket located at the nozzle exit to interface the vehicle OML to minimize loads to the thruster. Can you better define this interface and how to account for these loads for assessment? Said another way, does the OML to nozzle interface provide structural support to the nozzle, or does it create a moment arm? Answer to Q3: The modeling assumption being used at this time is that the gaskets do not have any significant stiffness and are not currently accounted for as a load path. This may be updated later as the design matures, but is not expected to be a driving condition. Question 4: The specified required qualification thermal test margin for operating temperature per section 4.1.4.3.3.1 is -37.8 degrees F below the minimum operating temperature of 41 degrees F. For components with active thermal control, can offerors assume that no temperature margin is required on the minimum temperature? For example, 3.2F is below the freezing temperature of hydrazine. NOTE: SMC-S-016 states that components w/ active thermal control require no temperature margin on the minimum temperature as long as heater power margin is maintained. Answer to Q4: For a wetted system, offerors may assume that no temperature margin is required on the minimum temperature. In the non-operational, unwetted state prior to use, this temperature margin still applies. Question 5: Does the 6 minute qualification vibration envelope multiple vibration events? For example, Earth and Mars launch. Answer to Q5: Yes. 6 minutes is to take in account of the duration of being launched from Earth as a payload and from Mars as a vehicle and is the envelope of both events. Question 6: Will the thruster valve inlets be wetted with propellant at the time of maximum shock/vibration exposure? Answer to Q6: Maximum shock events occur during separation of the inter-stage during Mars Ascent when the thruster valve inlets are wetted. Earth launch is the largest vibration event due to a base input payload random vibration requirement. The thruster valve inlets should not be wetted then. _________________________________________________________________________ 5/20/2021 Question 1: The RFP attachments are requested to be made available in the native format (e.g. word or excel). Answer to Q1: In order to maintain the integrity of the RFP attachments, NASA will not be providing the documents in native format. _______________________________________________________________________ NASA/Marshall Space Flight Center (MSFC) has issued a Request for Proposal for the Reaction Control System (RCS) 5N Thruster for the Mars Ascent Vehicle (MAV). See attachments for additional details.