This Small Business Innovation Research Phase I project will study in-situ measurements of the global stratosphere which are needed to quantify long-term changes, to improve the observations and parameteorization on which global numerical models are based, and to calibrate/validate indirect probing methods from ground or satellite sensors. Radiosondes routinely and inexpensively monitor the stratosphere, but provide only limited information; research aircraft, at great expense, operate sporadically and cannot reach the upper stratosphere. BLAG (Balloon Launched Autonomous Glider) expands on the radiosonde concept, and on the 1965 development by MacCready of the automatic homing miniature glider, with the aid of modem technology -- especially GPS navigation; miniaturization of sensors for turbulence, water vapor, and other parameters; and advanced aerodynamics and structures. The small instrument package is raised by balloon; it descends as a glider, covering substantial traverse distances, and lands at a pre-designated spot. The economic potential is to sell, and continually upgrade, these sophisticated BLAG systems that could substitute for (and expand the usefulness of) a large percentage of radiosondes. The approach is consistent with the AV motto of `doing more with less` BLAG will provide vital information that is at unobtainable in spite of giant past and planned investments in high altitude research aircraft programs.
