Aircraft Icing Research

Icing Research at WSU: Since 1984, Wichita State University is one of the top leading US universities engaged in the field of aviation icing research. Our current research programs attract nearly $1M USD of funding annually from the general aviation industry, state and federal agencies. We help contribute to aviation safety by conducting icing research and generate data for the Federal Aviation Administration (FAA), which aids the rulemaking process governing icing regulations and certifications. We also work closely with the Icing branch of NASA Glenn Research Center by performing fundamental studies on icing to develop numerical models that ultimately lead to the design of safer aircrafts operating in the icing environments. For example, the experimental droplet impingement studies with large water droplets showed that mass flux loss due to splashing is greater than anticipated, a factor that current icing computer models do not account for. Therefore, simulated ice shapes due to supercooled large droplets (SLD) are often different from the experimental measurements. The National Transportation Safety Board (NTSB) has already identified SLD icing as one of the major areas that requires significant amount of research. The Federal Aviation Administration (FAA) is currently proposing new icing regulations in the “Appendix X” icing envelope for aircrafts operating in SLD icing clouds such as freezing drizzle and rain.

WSU is currently leading the research into SLD and has already formulated new algorithms and devised unique test facilities and techniques for studying these kind of icings. We are also working with the international research establishments such Qinetiq (formerly Defense Establishment and Research Agency of United Kingdom), Cranfield University (United Kingdom), University City of London (United Kingdom), ONERA (France) and the Civil Aviation Authority of United Kingdom (CAA). For the past 20 years, WSU has generated numerous reports and publications to the FAA, NASA and major conferences in these areas: droplet impingement, supercooled large droplet (SLD) studies, anti-/de-icing systems, shed ice trajectories, pilot simulator, aerodynamic testing and computational fluid dynamic (CFD) studies.

Importance of Icing Research: In a recent report compiled by National Transportation Safety Board (NTSB) on all weather related accident for 1991 – 2001, icing accounts for 7.5% of all aircraft accidents (2010 NTSB Most Wanted List). A total of 445 aircrafts were involved including recent fatal icing encounters by American Eagle (ATR72-212) in Roselawn, Indiana, and Comair (EMB-120TR) in Monroe, Michigan.

One of the major Safety Recommendations by the NTSB:
“Reduce Dangers to Aircraft Flying in Icing Conditions”

The objectives of Safety Recommendations are to:

  • Use current research on freezing rain and large water droplets to revise the way aircraft are designed and approved for flight in icing conditions.
  • Give flight crew accurate information to quickly recognize dangers of all types of icing and maintain airspeeds to avoid loss of aircraft control.