Long extension reeling in the stratosphere - A progress report

Results of the second flight of the Harvard Reel Down balloon-born winching system, in which a more complex photochemical detection package was twice lowered from a float altitude of 39 km and reeled back to the winch, are reported. Modifications over the original package design include improvements to the winch platform and reconstruction of the suspended detection package for specific ClO measurement and for tight weight control. Controlled velocities of 4-7 m/sec were implemented for both of the scans, and the package was brought to a brief stop during the first scan to evaluate dynamic effects. The results demonstrate the operational effectiveness of the system.