According to China National Defense Science and Technology Information Network, as NASA and its business partners continue to advance towards the era of "low-traffic commercial crew transportation," Boeing has released a report on the U.S. Air Force X-37B aircraft (or "repeatable" "Using space planes" proposal. The proposal details the potential for implementing low-orbit freight and occupant transport missions by extending the capabilities of the X-37B. However, based on unknown reasons, NASA Commercial Space Department put the proposal aside.
What role can the reusable space aircraft play in the era of commercial crew transportation?
The idea of â€‹â€‹adding the X-37B to NASA's Commercial Rail Transportation Service (COTS) program and the Commercial Crew Utilization (CCDev) program came from the fact that the X-37B project was able to reduce costs and accelerate technology development through â€œfocus on payloadâ€. "Focus on payload" means that by using a mature spacecraft platform such as the X-37B and its defined platform load interface, as well as ground stations supported by sophisticated mission operators using flight-certified equipment, Significantly reduce single-use costs.
Boeing also pointed out that several key technologies for the repeated use of spacecraft have been successfully validated, including pneumatics, aerodynamics, repetitive solar sails, thermal protection systems (TPS), and autonomous guidance, navigation, and control (GNC).
Using the X-37B to Develop a Small Space Shuttle
Based on the NASA Future-X (1998-2001) and Aerospace Launch Initiative (2001-2006) activities, related personnel developed the X-37B to assist in reducing the cost of geo-orbital transmission in the post-space shuttle era and to replace "gradual progress. The "EEV" era.
In addition to testing the next generation of TPS system materials, the X-37B is also seen as a platform capable of testing autonomous derailment, access and landing GNCs; a fault-tolerant architecture capable of autonomous on-orbit and in-flight; capable of minimizing airport infrastructure , GPS and differential GPS landing; with electromechanical flight drive and braking system; using lithium-ion battery, long life, with a large current input and output capabilities.
In addition, the X-37B can also test reusable and retractable solar arrays, advanced graphite/bismaleimide (Gr/BMI) composite fuselage, complex carbon-carbon control surfaces, and advanced The high-temperature wing leading edge tile, hypersonic aerodynamic heating prediction method, and integrated system design are used for post-mission rear flight processing.
The X-37B's first mission lasted from April 22, 2010 to December 3, 2010, and was on track for 224 days. On December 3, 2010, the X-37B successfully implemented energy, altitude, attitude, and attitude by controlling its tilt angle, pitch angle, and S steering angle during the reentry flight of the X-37B spacecraft over 10,000 kilometers. Falling trajectory management.
More importantly, the X-37B has successfully evaluated its energy consumption as the spacecraft for the first time, and left the course correction cylinder (HAC) off the runway entrance to adjust for high altitude downwind conditions. The mobile HAC regulates wind and energy autonomously. The ability to change is only one of the improved guidance algorithms for approach and landing of space shuttle orbiters.
Adjusting the X-37 Design to Meet the Age of Commercial Space
The X-37B spacecraft is designed to provide a good way to "demonstrate, improve, validate competitive technologies and operational solutions without the need to create unique demonstrations to validate spacecraft."
The X-37B also provides a valuable testing platform where multiple competing technologies can be integrated into an orbital test vehicle (OTV) as an independent subsystem of the OTV. During a one-time demonstration flight to the International Space Station or on-orbit satellites, the X-37B can independently test these competing technologies without the need for separate testing of individual technologies.
X-37 Performing International Space Station Mission
After the space shuttle was retired in 2011, the ability to return sensitive goods from the international space station was also lost because it required a soft landing. The X-37 is currently the only aircraft that can provide a 1.5-g level soft landing capability.
After landing on the runway, sensitive cargo can be safely and quickly removed from the X-37B cargo bay. According to the current size of the X-37B, cargo destined for the International Space Station can be placed inside and outside the cargo compartment of the X-37B payload, and cargo returned to the ground is placed in the cargo compartment of the payload.
According to this proposal, using the X-37B with an additional service module, launch into a 51.6Â° inclined orbit and meet with the International Space Station. Upon arrival at the International Space Station, the X-37B will go on its own to enter the docking area of â€‹â€‹the International Space Station Teleoperation System (SSRMS). Then, the International Space Station occupant extended the SSRMS, grabbed the X-37B, and took it to the CBMS at a node module on the station.
During the docking process, the X-37B does not require support from the International Space Station. It only requires the connection of a universal docking mechanism. All power and power will come from the deployed solar array and the batteries on the aircraft. International Space Station occupants use SSRMS to remove external cargo from the X-37B's external attachment point. The internal cargo for the International Space Station will be enclosed in the X-37B payload container, which facilitates the occupant's handling.
Afterwards, all the goods returned to the ground will be loaded into these containers, and the containers will be loaded into the X-37B effective load. After the docking operation is completed, SSRMS will detach the X-37B from the International Space Station. The X-37B will be separated from the service cabin and derailed into the atmosphere, descending and landing.
Development of human-type X-37B
Boeing believes that the current size of the X-37B will increase by 160 to 180%, giving it the ability to accommodate 5-7 astronauts. According to this design, the X-37 can accommodate 5 to 6 astronauts and can also accommodate an injured astronaut (possibly needing a single frame or the like).
The astronaut seat will be placed on the side of the X-37 with a pressurized capsule, leaving a channel for the launch pad to climb and zero gravity operations. The occupants enter from the top hatch of the X-37 and in case of emergency, this exit is also used for escape. In the event of a flight anomaly, the push-type anomalous system between the upper level of the Aster 5 and the X-37 will provide the appropriate acceleration, and the delta-4 rocket will provide thrust. The manned X-37 can launch, suspend, rendezvous, dock, dock, derail, and land itself completely without crew assistance. (China Academy of Aerospace Science and Engineering Xu Hongying Chen Jie)
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