A final intercomparison between the P-3B and DC-8 was planned for this flight. The intercomparison was planned to include a 20 minute leg at 17.5 Kft, a descent to 1000 ft at 500 ft/min., and another 20 minute leg at 1000 ft.  The P-3B then planned to turn 180 degrees and retrace the leg at 1000 ft to allow for a test of the Georgia Tech aerosol composition measurement with and without the removal of large particles (>1 micron).  Given time constraints, the P-3B would then have to ascend to maximum altitude and proceed to Dryden.

 Results: The intercomparison with the DC-8 went as planned with all instruments in operation.  The reverse track at 100 feet also went as planned with similar conditions and no problems with encountering exhaust from the previous pass.  At high altitude heading for Dryden, clean conditions (e.g., 65 ppbv O₃, 100 ppbv CO, 150 pptv NOy) were encountered, followed by stratospheric conditions (e.g., O3 >200 ppbv).  At the end of the flight, convective activity over the west coast was encountered.  Some large fluctuations in NO were observed (> 500 pptv).  These fluctuations were most likely due to convective pumping of polluted air since the stormscope detected no lightning activity