USML-2 Public Affairs Status Report #22 6:00 a.m. CST, Nov. 02, 1995 12/22:07 MET Spacelab Mission Operations Control Marshall Space Flight Center "Things are going fantastically well, and we're just looking forward to getting as much science in the remaining time as we can," explained USML-2 Alternate Payload Specialist Glynn Holt early this morning in an interview for Mutual NBC Radio as fluid physics and combustion science took center stage on the thirteenth night of the second United States Microgravity Laboratory mission. Spacelab systems and facilities continued to operate well and gather good data. The crew worked with the Fiber Supported Droplet Combustion experiment in the Glovebox, performed the fission experiment in the Drop Physics Module, monitored fluid flows for the Geophysical Fluid Flow Cell experiment, and initiated the last run of the Supression of Transient Acceleration by Levitation Evaluation (STABLE) vibration isolation system. "Fred gets an A+ in combustion theory," exclaimed investigators for the Fiber Supported Droplet Combustion experiment (FSDC), offering Payload Specialist Fred Leslie "a collective high-five" for his "outstanding work" in the Glovebox facility. Leslie had been placing drops of fuel on a thin fiber, using needles in the experiment module, and igniting them with a hot wire. Earlier in the evening, Leslie worked closely with the FSDC science team to successfully troubleshoot difficulties with clogged drop accumulators, and then performed a series of excellent burns, varying the quantities of methanol and methanol/water fuel with each run. Also varied were fiber size and air flow rates. These experiments resulted in some droplet extinction diameters (the size of the drop as it burns out) larger than any initial droplet size capable of being studied on Earth. The science team was very pleased with what they described as the "textbook quality" data received and expressed their appreciation for the crew's hard work and persistence. Leslie showed his enthusiasm for the work when he humorously responded, "I don't get to play with fire much up here. I'm kind of enjoying it." The NASA Lewis Center's FSDC investigation consists of new hardware and is on its first flight. The primary objective for this research is to provide scientists new fundamental insights into the dynamics of droplet burning which will be compared to state of the art analytic and numerical models. "It did fission, and I got some good data," announced Mission Specialist Cady Coleman referring to the initial drop fissioning runs in the Drop Physics Module. Coleman used sound waves to manipulate rotating drops of silicone oil until they split, or underwent fission. Project Scientist Arvid Croonquist and his science team worked with Coleman throughout the night, uplinking instructions and watching downlink video. They were testing one set of theories that describes the breaking apart of distorted, or pre-flattened, drops while varying the viscosity (or thickness) of the fluid. Drop Dynamics Experiment Principal Investigator Taylor Wang and his co-investigators from Vanderbilt University observed and analyzed conditions at which drops of various sizes and viscosities split, and he described Coleman's first run of the procedure as "a very successful drop fission." Also, during this run, the science team was able to get good pictures of the ligament, or thread of fluid, connecting the two halves of the drop as it passed through its critical "saddle" point while splitting in two. On the first USML mission, Wang's team used the Drop Physics Module to confirm a theory that was more than 100 years old. Using fluids ranging from water to oils, the module spun single drops until they formed a dog-bone, or two lobe shape. All the drops changed into the same shape at the same point and at exactly the point that had been predicted over a century ago by fluid dynamics pioneer Lord Raleigh. Results from USML-2 are helping to develop theoretical models for the drop fission process. Troubleshooting continues on the High Data Rate Recorder (HDRR), which began experiencing intermittent data degradation between MET 12/14:30 and 12/14:58. Scientific data is being stored on the Orbiter's recorder during loss of signal periods and downlinked via Hi-Pac TV. The Space Acceleration Measurement System (SAMS) and the Orbital Acceleration Research Experiment (OARE) continued to track accelerations caused by movements and variations within the Shuttle, as well as by Shuttle maneuvers and atmospheric drag. The Principal Investigator Microgravity Services Project team, of NASA's Lewis Research Center, is at the Spacelab Mission Operations Control Center to help scientists evaluate the effects of accelerations on sensitive microgravity experiments. Both instruments make continuous records of accelerations for analysis after the flight. In addition, OARE is providing data on the relatively steady, or low-frequency, accelerations that occur in the Shuttle. This information is being provided to the USML-2 Principal Investigators in real-time throughout the mission. The crew also activated the STABLE instrument, and unattended monitoring continued during the final run of the device. The STABLE system was developed by NASA's Marshall Space Flight Center jointly with McDonnell Douglas to test a device designed to isolate small science experiments from high-frequency accelerations, including Shuttle maneuver operations and crew activity. Work in the Drop Physics Module and the Glovebox will continue over the next twelve hours as the second United States Microgravity Laboratory Mission enters its fourteenth day in orbit. Status reports are issued from Johnson Space Center's Mission Control at 8 a.m. and 5 p.m.; and from Marshall Space Flight Center's Spacelab Mission Operations Control at 6 a.m. and 6 p.m. weekdays, 6 a.m. on weekends. For additional information, see the Internet USML-2 payload homepage, http://liftoff.msfc.nasa.gov/spacelab/usml2/welcome.html and the STS-73 Shuttle homepage, http://shuttle.nasa.gov.