Abstract: Aircraft engine condensation trails or contrails are of interest to military mission
planners, meteorologists, climatologists and conspiracy theorists. Climatologists have been
studying commercial aircraft for the past decade. Recently persistent contrails have been
declared equal to CO2 impact on climate. This lecture will start with a review of
thermodynamic phase, state, vapor pressure definitions and psychrometrics (the science of
water and air mixtures). The lecture will continue with basic contrail formation/dissipation
process, contrail factor chemistry, contrail prediction techniques and the contrail forming
characteristics of turbojets, medium, high bypass ratio engines. Public domain contrail
detection, contrail avoidance and elimination techniques will be presented. The presentation
will include a brief synopsis of current commercial engine contrail management activities.
Biography: Mr. Gary Wollenweber is Consulting Engineer Infrared and Thermal Design for
GE Aviation’s Engineering Division in Cincinnati OH. Mr. Wollenweber’s primary
responsibilities include engine infrared and visible signature, suppression design, technology
integration, analytic assessment, measurements and leadership of infrared and thermal design
product teams. Mr. Wollenweber has 45 years of experience in aircraft engine thermal design
and has specialized on exhaust nozzle cooling and signature control technology since 1984.
Mr. Wollenweber has Physics (Wabash College, 1974) and Mechanical Engineering (BS
Purdue 1975, MS Purdue, 1977) degrees and is a registered Professional Engineer.