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Nakazono, Barry

Publications and source records attributed to Nakazono, Barry.

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

A Single Stage to Orbit Design for a Hybrid Mars Ascent

A Single Stage to Orbit (SSTO) hybrid propulsion system has been previously studied as an option for a conceptual Mars Ascent Vehicle (MAV). The hybrid motor uses a wax-based fuel developed specifically for this application, so it can take advantage of a single port design. The oxidizer is Mixed Oxides of Nitrogen (MON-25). Higher Nitric Oxide concentrations have been discussed in the past, however, the lower temperature capability is no longer needed. The MAV Payload Assembly (MPA), which would house the Orbiting Sample (OS) has changed substantially from previous iterations and has become more compact. Benefits of the hybrid option include its predicted low temperature behavior, high performance and ability to restart (enabling the SSTO). However, the hybrid technology remained at a relatively low Technology Readiness Level (TRL). In an attempt to increase the TRL, a technology development program has been underway for the past four years. The results of the technology development program are now being incorporated to an updated concept for a hybrid Mars Ascent Vehicle, with the eventual goal of informing a hybrid propulsion design that closes under the guidelines currently envisioned for a potential Mars Sample Return campaign. This paper focuses on the hybrid propulsion system design and the preliminary results from the first part of the FY19 technology development program (October 2018 to July 2019) and includes some results from a Preliminary Architecture Assessment (PAA) study. In the PAA, experts from all relevant subsystems (propulsion, avionics, GN&C, structures, thermal, etc.) are brought together to determine an updated vehicle design. The PAA is being run out of Marshall Space Flight Center (MSFC) in coordination with the Mars Sample Return study lead by the Jet Propulsion Laboratory (JPL). Currently, it is thought that the Mars Ascent Vehicle would be housed in a Sample Retrieval Lander (SRL), along with a fetch rover. The SRL would be responsible for several crucial functions on the MAV including heating, erection and providing the ignition signal. This paper will also outline the future testing and path forward through the rest of the fiscal year. This includes full scale testing at Whittinghill Aerospace, hypergolic additive testing at Purdue, evaluation of adding hypergolic additives to a full-scale grain. A hybrid fuel formulation has been updated with a reduced regression rate, which again was developed by Space Propulsion Group. This design will be used to determine the benefits of a hybrid versus solid propulsion system for a MAV, as they fit into the larger vision for a potential Mars Sample Return campaign.

Story, George↗
NASA NTRS2019

Final Dawn Reaction Control System (RCS) propulsion system in-flight characterization

The Dawn spacecraft concluded eleven years of operations on 31-Oct-2018, upon depletion of its hydrazine supply in Ceres orbit during the second extended mission. Dawn’s Reaction Control System performed admirably during this lengthy campaign, including years of unanticipated and novel operation given Reaction Wheel Assembly failures during flight. New and modified modes of thruster operations were implemented during the mission. Pressure transducer drift was negligible, consumable limits were generally not exceeded (except for minor violations in Reaction Control System thruster cycles), and thruster performance was nominal throughout this long interplanetary journey. Tank models of hydrazine remaining mass were consistent with depletion within uncertainties, although thruster consumption-based models ended up being conservative by 15%. Unexpectedly, apparent nitrogen permeation through the hydrazine tank elastomer diaphragm allowed hydrazine in the lines below the tank to be pressurized and subsequently utilized during the final days of the mission.

Mizukami, Masashi↗
NASA NTRS2019

Final Dawn Reaction Control System (RCS) propulsion system in-flight characterization

The Dawn spacecraft concluded eleven years of operations on 31-Oct-2018, upon depletion of its hydrazine supply in Ceres orbit during the second extended mission. Dawn’s Reaction Control System performed admirably during this lengthy campaign, including years of unanticipated and novel operation given Reaction Wheel Assembly failures during flight. New and modified modes of thruster operations were implemented during the mission. Pressure transducer drift was negligible, consumable limits were generally not exceeded (except for minor violations in Reaction Control System thruster cycles), and thruster performance was nominal throughout this long interplanetary journey. Tank models of hydrazine remaining mass were consistent with depletion within uncertainties, although thruster consumption-based models ended up being conservative by 15%. Unexpectedly, apparent nitrogen permeation through the hydrazine tank elastomer diaphragm allowed hydrazine in the lines below the tank to be pressurized and subsequently utilized during the final days of the mission.

Mizukami, Masashi↗
NASA NTRS2019

Thermal design and validation of Mars 202 gas Dust Removal Tool (gDRT)

As part of the science goals for the planned Mars 2020 mission, two instruments, PIXL and SHERLOC, intend to study the Mars surface at a close scale. These two instruments are planned to be used on smooth rock surfaces that are free of dust and other particles. Such surfaces are prepared by using a drill with an abrading drill bit; residual dust and particles are then blown away using a compressed gas system—the Gas Dust Removal Tool (gDRT). Early in the design process a risk of valve leakage below the vendor’s -20C rating was identified. To mitigate this risk a parallel path was implemented: 1) qualify the valves to operate at -135C, and 2) develop thermal control capability to elevated temperatures in case qualification efforts are unsuccessful. While qualification efforts are ongoing, it is expected that the valves will be qualified to an operating temperature of -135C. In the event that qualification is not successful, thermal control has been realized via a thermally isolated valve configuration and thermostatically controlled heaters. Thermal testing of gDRT has validated this design and enabled thermal model correlation in order to provide more accurate survival energy predictions. The resulting energy consumption for heating the valves at the Jezero landing site represents a minimal impact to the Rover energy budget.

Novak, Keith↗
NASA NTRS2019

Mars Ascent Vehicle Hybrid Propulsion Development

Mars Ascent Vehicle Study Agenda: Potential Mars Sample Return (MSR); Potential Hybrid Design; 2019 Preliminary Architecture Assessment; Propellant Combination - Fuel; Propellant Combination - Oxidizer; Full Scale Testing thru 2018; Hypergolic Ignition; TEA/TEB (triethylaluminum/triethylborane) Ignition; Solid Hypergolic Additives; 2018 test - longest duration test; 2019 test; Liquid Injection Thrust Vector Control; White Sands Test Facility; FY19 and Future Work; Summary.

Story, George↗
NASA NTRS2019

Hybrid propulsion technology development for a potential near-term Mars Ascent Vehicle

A technology development program for a potential hybrid Mars Ascent Vehicle (MAV) is currently underway to enable its infusion into a potential Mars Sample Return (MSR) campaign as early as 2026. A NASA team from the Jet Propulsion Laboratory (JPL), Marshall Space Flight Center (MSFC) and Ames Research Center (ARC) is leading and coordinating this program. A new propellant combination: the wax-based fuel, SP7, and MON-30 were proposed for a hybrid option for the MAV propulsion system several years ago. Since that time, hotfire testing with a similar propellant combination (SP7/MON-3) has been completed and a pathway to achieving high performance with the flight propellant combination is currently being pursued. Highlights of the progress to date and plans for risk reduction and the next steps in hybrid technology will be presented.

Zilliac, Greg↗
NASA NTRS2018

Technology Development for a Potential Hybrid Mars Ascent Vehicle

With Mars Sample Return mission concepts being considered for launch as early as 2026, technology development to enable this potential campaign is currently underway. One of the critical items in the campaign would be a Mars Ascent Vehicle, which would be responsible for getting the samples from the surface of Mars to orbit around Mars. This would be the first rocket launch from another planet. Therefore, several challenges arise due to the Martian atmosphere and remote location. A technology development program to determine the feasibility of a hybrid rocket for a Mars Ascent Vehicle is entering its fourth year. Highlights and successes of this program will be discussed.

Oglesby, Britt↗
NASA NTRS2018

Supersonic Retropropulsion on Robotic Mars Landers: Selected Design Trades

Many concepts for future robotic Mars lander missions require landing heavier payloads than those landed to date. Mars lander architectures to date have relied on a parachute to help slow the lander; however the effectiveness of a parachute in the thin Martian atmosphere is diminished with heavier payloads unless the diameter of the parachute is increased or it is deployed at a higher Mach number, both of which are significant technical challenges. In addition the parachute can be successfully deployed only within a specific Mach number and dynamic pressure range. Targeting the entry trajectory to hit this “Mach-Q box” imposes constraints on the entry ballistic coefficient, limiting it to ~ 150-200 kg/m^2. Eliminating the parachute from the design requires descent engine ignition at supersonic speeds (Supersonic Retropropulsion, or SRP). SRP increases the propellant requirement, but also allows entry ballistic coefficients of ~600 kg/m^2 or more, with the consequence of significantly increased entry mass and landed payload mass.

Lorenz, Christopher G.↗
NASA NTRS2018

Update on Technology Development Plan for a Low Temperature Hybrid Mars Ascent Vehicle Concept

Technology development to mature a hybrid rocket option for a potential Mars Ascent Vehicle has been underway at the Jet Propulsion Laboratory and Marshall Space Flight Center. A conceptual design was completed in 2016 and has been used to determine the motor size for risk reduction development. The task plan for the FY17 testing, actually completed in mid FY18, is discussed. The major achievement of this effort was successful full scale hotfire testing with a representative ambient Earth storable propellant combination: SP7/MON3. A near term plan, through July 2019 is briefly discussed.

Prince, Andrew↗