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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 379 records · Page 21
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Dynamic Routes for Arrivals in Weather (DRAW)

A brief overview of the ATD-3 DRAW tool for assisting Traffic Management Coordinators with rerouting flights impacted by convective weather in a arrival- metered air traffic environment.

Weather Avoidance, TBFM, Scheduling, TMC, Arrival ↗
NASA NTRSDate not supplied

Trajectory Design for a Spacecraft Capable of Deploying Probes to the Martian Surface en Route to Low Mars Orbit

The presented trajectory design and analysis was performed for the Aeolus spacecraft mission concept. The Aeolus spacecraft consists of an orbiter (i.e., “mothership”) with the goal of transferring from Earth to low Mars orbit via propulsive and/or atmospheric braking (i.e., aerobraking). During various phases of flight from hyperbolic approach of Mars through low Mars Orbit, the Aeolus orbiter will deploy multiple probes which are targeted to land on the Martian surface with the goal of achieving global surface coverage.

Mars hyperbolic approach↗
NASA NTRS2022

Preliminary Characterization of Unmanned Air Cargo Routes Using Current Cargo Operations Survey

The introduction of regional cargo unmanned aircraft systems into the National Airspace System is anticipated within the coming years. Because they are remotely piloted, these aircraft are expected to utilize increasing aircraft automation and autonomy, require special infrastructure accommodations for navigation, communication, command and control and potentially need special treatment from air traffic control. In order to assess the accessibility and impacts of these operations across the national airspace, this preliminary study investigates current and estimated future demand for air cargo operations in the continental United States. Air cargo demand is broken down by aircraft type and airport categories to produce a rough nation-wide classification of cargo operations. Then, the state of Texas is investigated as a focus region, where the impacts of regional cargo unmanned aircraft systems on the airspace are investigated in further detail. The potential technologies that can assist in regional cargo unmanned aircraft system accessibility are defined at airports across the focus region. A single airport, Fort Worth Alliance, is highlighted to discuss airport-level statistics. Finally, a qualitative classification of airports by the type of cargo operations is suggested.

Unmanned Aircraft↗
NASA NTRS2022

Preliminary Characterization of Unmanned Air Cargo Routes Using Current Cargo Operations Survey

The introduction of regional cargo unmanned aircraft systems into the National Airspace System is anticipated within the coming years. Because they are remotely piloted, these aircraft are expected to utilize increasing aircraft automation and autonomy, require special infrastructure accommodations for navigation, communication, command and control and potentially need special treatment from air traffic control. In order to assess the accessibility and impacts of these operations across the national airspace, this preliminary study investigates current and estimated future demand for air cargo operations in the continental United States. Air cargo demand is broken down by aircraft type and airport categories to produce a rough nation-wide classification of cargo operations. Then, the state of Texas is investigated as a focus region, where the impacts of regional cargo unmanned aircraft systems on the airspace are investigated in further detail. The potential technologies that can assist in regional cargo unmanned aircraft system accessibility are defined at airports across the focus region. A single airport, Fort Worth Alliance, is highlighted to discuss airport-level statistics. Finally, a qualitative classification of airports by the type of cargo operations is suggested.

Unmanned Aircraft, Unmanned Aircraft Systems, UAS,↗
NASA NTRSDate not supplied

Trajectory Design for a Spacecraft Capable of Deploying Probes to the Martian Surface en Route to Low Mars Orbit

The presented trajectory design and analysis was performed for the Aeolus spacecraft mission concept. The Aeolus spacecraft consists of an orbiter (i.e., “mothership”) with the goal of transferring from Earth to low Mars orbit via propulsive and/or atmospheric braking (i.e., aerobraking). During various phases of flight from hyperbolic approach of Mars through low Mars Orbit, the Aeolus orbiter will deploy multiple probes which are targeted to land on the Martian surface with the goal of achieving global surface coverage.

Mars hyperbolic approach↗
NASA NTRSDate not supplied

Resonant Pulse Combustors: A Reliable Route to Practical Pressure Gain Combustion

Pressure Gain Combustion (PGC) defined: A fundamentally unsteady process whereby gas expansion by heat release is constrained, causing a rise in stagnation pressure and allowing work extraction by expansion to the initial pressure. A particular type of pressure gain combustion (PGC) device is described, which is under investigation at GRC (Glenn Research Center). The Resonant Pulse Combustor (RPC) has been largely overlooked due to its theoretically low performance. However, its practical performance is quite competitive with other PGC systems, and its physical simplicity is unmatched.

combustion↗
NASA NTRS2023

Impact of COVID-19-related Air Traffic Reductions on the Coverage and Radiative Effects of Linear Persistent Contrails over Conterminous United States and Surrounding Oceanic Routes

The radiative effects of the large-scale air traffic slowdown during Apr and May 2020 due to the international response to the COVID-19 pandemic are estimated by comparing the coverage (CC), optical properties, and radiative forcing of persistent linear contrails over the conterminous United States and two surrounding oceanic air corridors during the slowdown period and a similar baseline period during 2018 and 2019 when air traffic was unrestricted. The detected CC during the slowdown period decreased by an area-averaged mean of 41% for the three analysis boxes. The retrieved contrail optical properties were mostly similar for both periods. Total shortwave contrail radiative forcings during the slowdown were 34 and 42% smaller for Terra and Aqua, respectively. The corresponding differences for longwave contrail radiative forcing were 33% for Terra and 40% for Aqua. To account for the impact of any changes in the atmospheric environment between baseline and slowdown periods on detected CC amounts, the contrail formation potential (CFP) was computed from reanalysis data. In addition, a filtered CFP (fCFP) was also developed to account for factors that may affect contrail formation and visibility of persistent contrails in satellite imagery. The CFP and fCFP were combined with air traffic density data to create empirical models that estimated CC during the baseline and slowdown periods and were compared to the detected CC. The models confirm that decreases in CC and radiative forcing during the slowdown period were mostly due to the reduction in air traffic, and partly due to environmental changes.

contrails↗
NASA NTRS2024

Route-Recapturing State-Based Horizontal Maneuver Strategy for Automated Detect-and-Avoid

This report describes a novel approach to the development of a horizontal maneuver guidance strategy for Detect-and-Avoid systems. The maneuver guidance strategy provides a directive turn action that can be automatically executed by the vehicle’s auto-pilot system, taking into account the cost of recapturing the flight plan path. Pairwise conflict scenarios with non-accelerating intruders are simulated to validate the effectiveness of the maneuver guidance strategy. Initial results suggest the strategy is more effective for faster ownship than for slower ownship, which is unable to avoid conflict in certain scenarios against fast intruders. These findings indicate this novel approach shows great potential, but improvement to its performance is necessary and will be future work.

detect-and-avoid↗