Aiaa 2001-4057

Simulation-to-Flight” is a research development concept to reduce costs and increase testing efficiency of future major aeronautical research efforts at NASA. The simulation-to-flight concept is achieved by using common software and hardware, procedures, and processes for both piloted-simulation and flight testing. This concept was applied to the design and development of two full-size transport simulators, a research system installed on a NASA B-757 airplane, and two supporting laboratories. This paper describes the software system that supports the simulation-toflight facilities. Examples of various simulation-toflight experimental applications were also provided. Introduction In 1974, NASA Langley Research Center (LaRC) obtained a research airplane, a Boeing 737-100 series aircraft, to conduct aviation systems and operational research for the Advanced Transport Operating Systems (ATOPS) program. The standard airplane systems were modified and interfaced to a separate research system. The airplane was named the Transport Systems Research Vehicle (TSRV) and could be flown from take-off through landing from the conventional forward flight deck or from a full-size, two-crewmember, research aft flight deck (AFD). The AFD was located in the passenger cabin. Thrust and flight control inputs were made by the AFD crew through control inceptors or through a research autopilot system via a fly-by-wire computer system. During flight research operations, the AFD was generally flown by test subject crews while the forward flight deck was manned by safety * Computer Engineer, Systems Development Branch Copyright  2001 by the American Institute of Aeronautics and Astronautics, Inc. No copyright is asserted in the United States under Title 17, U.S. Code. The U.S. Government has a royalty-free license to exercise all rights under the copyright claimed herein for Governmental purposes. All other rights are reserved by the copyright owner. pilots to monitor, engage, and disengage the aft flight deck as an in-flight safety measure. Besides the aft flight deck, the research system installed in the airplane consisted of four other major experimental subsystems: three flight control computers, a navigation and guidance system, an electronic display system, and a data acquisition system. Navigation, guidance, and flight control computer software were hosted on a MicroVAX computer, while the display software was hosted on another MicroVAX computer. An integrated Air Data Inertial Reference System (ADIRS) unit was used to provide accelerations, velocities, airplane position, and standard air data information to the research system. An experimental digital data bus called the Digital Autonomous Terminal Access Communications (DATAC) was developed to provide transport data from various sensors and research pallets throughout the airplane. The DATAC was a copper-based physical communication media which was later commercially recognized as a prototype of the ARINC 629 standard and was used as a computing network between research subsystems. A development, verification, and validation laboratory, known as the Experimental Avionics Systems Integration Laboratory (EASILY), was used to develop, integrate, and preflight-validate the hardware and software systems for a TSRV flight test. The EASILY was equipped with VAX 4000-200 computers to provide simulation modeling, flight management system software, data acquisition functions, and graphic display generation. Interface units for testing signals associated with the ADIRS unit and the DATAC unit were also installed in the EASILY to mimic the architecture onboard the TSRV airplane. A ground-based simulator, similar to the AFD in the TSRV airplane, was built and used to conduct simulation-only or simulation and flight test research sponsored by the ATOPS program. The TSRV simulator was equipped with eight electronic monitors,