Effective Operation of a Storm-Penetrating Aircraft

While most pilots try to stay far from the core of a strong thunderstorm, research pilots are sometimes asked to do just the opposite. The next severe storm penetrating aircraft, an A-10 Thunderbolt II is being readied to fly research missions into thunderstorms. An earlier armored storm penetrating aircraft, a T-28 operated by the South Dakota School of Mines and Technology, safely performed thousands of storm penetrations during its three decades of service from the 1970's into the early 2000's. Based on experience gained during these operations, it is clear that a key to effective and safe operation is close monitoring on the ground of (1) aircraft position overlaid on a high-quality frequently-updated meteorological radar display,(2) ground display of key observations from airborne instruments, (3) effective ground-air voice communications. Monitoring of surface weather and satellite cloud observations also is important. With this information and reliable ground-air communications a flight controller on the ground can brief the pilot on desired altitudes and headings for penetrations, and potential safe escape headings if unexpectedly severe conditions are encountered in-cloud. Such a communications link also allows the pilot to brief the controller on conditions being encountered to verify inferences based on radar and other observations available on the ground. The A-10 will be equipped with a satellite communications system in addition to aircraft VHF communications, allowing both line-of-sight and over-the-horizon operation. A demonstration will be presented of software that will be utilized for flight monitoring. Illustrations will be given of desirable update rates for position and scientific data from the aircraft, and for observations from radar, and other platforms involved in a coordinated field study. In general, during convective storm penetrations, aircraft data should be updated every few seconds. Radar data ideally should be updated at least every few minutes. Higher update rates are desirable. With dedicated research radars, higher update rates are possible. Update rates can be as long as 8-12 minutes from the operational National Weather Service WSR-88D radar network.