Developing a distributed, large-channel-count data acquisition system with real-time and historical data analysis capabilities from multiple remote display clients can be very time consuming. However, using National Instruments' LabVIEW to implement a distributed architecture that takes advantage of built-in networking protocols, has saved Cal-Bay Systems weeks of custom software development time. Sorin Grama reports Testing aircraft components such as turbines and generators requires dedicated test facilities that can subject the unit under test (UUT) to extreme pressures, temperatures, and other conditions similar to those encountered in real-life operating mode. Researchers initiate and monitor qualification tests from a control room, featuring multiple computer stations dedicated to specific tasks such as pressure and flow control, safety monitoring and simulation. During a test run, teams of engineers, technicians, and analysts work together to collect and analyse real-time and historical data from various subsystems. The atmosphere is similar to that of a space flight control room - everyone focuses on the UUT, but with a different perspective. A data acquisition system that acquires, displays, and records the critical test data is at the heart of this activity. Honeywell Engines, Systems & Services in Torrance, California, challenged Cal-Bay Systems with the task of implementing such a system. The brief was to design a system that could collect more than 2,000 channels at sampling rates varying from 1Hz to 100Hz. In addition, the system had to make test data instantly available to six client PCs for display and on-the-fly analysis and collect every data point and store it to a central location where it could be available immediately for historical analysis using specialised software tools. Finally, the system needed to seamlessly switch back and forth between on-the-fly and historical data analysis. Honeywell required a networked, distributed data acquisition hardware architecture, to reduce the wiring throughout the test facility, and the system had to interface to multiple Ethernet-based data acquisition devices. Besides collecting and logging data, the system needed to make the data available to a separate facility control computer, which would run the control loops for various pressure, flow and temperature subsystems. Because of the real-time control requirement, the system had to publish the data to the control computer at a deterministic rate of 100Hz using a real-time, dedicated network. Finally, this application required data integrity maintenance. The system could never duplicate a test run; therefore, it had to acquire all the channels and store them for post-acquisition analysis. Previously, engineers built data acquisition systems using various PC platforms, all of which had a concentrated architecture, and these could acquire and display only a very limited number of parameters. Engineers connected all instrumentation to a single PC, resulting in long wiring runs, which increased susceptibility to electromagnetic interference and physical damage. These systems were also limited to one data viewing station, which prevented multiple users from analysing the incoming data in real time. The solution Cal-Bay Systems based its hardware design on the PXI platform for its ruggedness and multiple analogue and digital I/O hardware offerings. SCXI hardware was used to expand the channel number and provide signal conditioning to sensors such as thermocouples and flow meters. A PXI controller running LabVIEW Real-Time as the main data acquisition engine and communicating with a host PC through a real time reflective memory interface, was selected. The host PC stores the data to a RAID disk array and, at the same time, makes it available to the client PCs for display.