The NRC has undertaken aviation emissions flight research. Principally aimed at Heavy and Super Jet Transports, the project has applied the NRC T-33 to measure condensation nuclei (CN), black carbon (BC), volatile organic compounds (VOC) and oxides of nitrogen (NOy) from aircraft flying enroute at high altitude. Most recently, the T-33 and flight profiles, developed under the research, have been applied to the comparative measurement of jet biofuel emissions. During the course of the project, techniques have been developed, for the derivation of estimated Emission Indices (EI) of pollutant species, measured on the ground (during taxy, departure or arrival runway operations) or inflight. In particular, if the jet engine exhaust jet streams were very young, air temperature measurements were used to correlate to empirically modeled turbulent jet mixing fluid dynamics, thereby deriving the applicable dilution factors (DF) to apply to the measured concentrations. For exhaust plumes which were not very young (i.e. not in a state of turbulent mixing, but rather in a state of turbulent or quiescent diffusion), flight data has involved techniques for the full cross-sectional measurement of wakes, including jet wake and wake vortex regimes. Not only has this captured the nature of wake structures under very strong static and dynamic influences, but permitted the measurement of aerosol emission index numbers directly. © 2012 by The Crown in Right of Canada. Published by the American Institute of Aeronautics and Astronautics, Inc. ; peer reviewed: yes ; NRC Pub: yes