Millar, R., Mazzuchi, T., and Jonsson, H., "A Suitable Platform for Storm Penetration, Risk Analysis for the SPA-10 Aircraft Modification," SAE Technical Paper 2016-01-2043, 2016, doi:10.4271/2016-01-2043.
The SPA-10 project, sponsored by U.S. National Science Foundation, is to acquire and qualify a replacement for the retired T-28 “storm penetration” aircraft previously used to acquire meteorological data to enable understanding and modelling of mid-continent thunderstorms. The National Science Foundation selected the Fairchild A-10 (bailed from the U.S. Air Force) as the platform to be adapted to perform the storm penetration mission to altitudes of eleven kilometers, and funded Naval Postgraduate School’s Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) as prime contractor. An expert panel conducted a review of the SPA-10 project in 2014 and recommended a risk analysis addressing hazards to the aircraft and pilots, such as icing, hail, turbulence and lightning. This paper presents the results of the risk analysis performed in response to this need, including recommended mitigations.In general the A-10 aircraft systems and structure were shown to be robust and suitable, reinforced by an operational plan for incremental exposure to the full force of the storm. A key challenge was obtaining the necessary information to resolve the expert panel’s concerns for a military aircraft designed in the 1970’s, with significant upgrades since, for a radically different mission. The support and assistance of the USAF and the engine manufacturer, General Electric was critical to this endeavor. The participation of the operator of the previous storm penetration T-28 aircraft, the South Dakota School of Mines and Technology, was a crucial source for understanding the mission and operational environment.