Oil mapping flights were conducted by two observers flying in an HU-16E 

 at 500 feet or below at a speed of 145 knots. Continuous visual contact with 

 the sea surface was maintained from shoreline departure until return. A 

 grid-like search track was used, consisting of station points every 10 miles 

 (or an average of 4.2 minutes) flying time. Loran A, radar, and TACAN were 

 used as navigational aids. Infrared sea surface temperatures were measured 

 by a Barnes PRT-5 radiometer and recorded continuously on an analog strip 

 chart recorder to a precision of 0.1°C and an accuracy of + 0.6°C. Visual 

 sightings of oil, size, direction of surface drift, and time of observation 

 were annotated on the IR strip chart trace. The oil sightings were also 

 noted on a plotting chart, which was a duplicate of the navigator's chart. 

 Concentrations of oil were separated by a core and shell limit contours. 

 Percentage of concentration and size were determined by a gridded viewing 

 device, a clear plastic grid divided into 25 squares. This device had an 

 inclinometer attached to the side. When viewing from the aircraft in level 

 flight, the observer could thus determine not only the area of an object on 

 the surface, but also the percentage of surface covered. At fractional 

 surface area coverages of less than 5 to 10%, the visual estimates appear to 

 be high by a factor of 2 to 4, but it is hoped that good NASA or AMSI over- 

 flights with photographic coverage will provide a scalar correction factor 

 for these low surface coverages. Also plotted with the oil sightings were 

 surface temperature contour crossings. These strong thermal gradients are 

 indicators of current boundaries, and will aid in the overall analysis. 



The H-3 helicopter missions generally were aimed at measuring oil trans- 

 port processes and collecting oil samples. During these flights, current 

 measurements were acquired with Richardson current probes, while differential 

 oil/water velocities were measured by means of time lapse photography and 

 special range finders to record the separation of oil pancakes and dye mark- 

 ers in the water. Oil samples from the slicks were taken using a small 

 bucket, with the helicopter hovering at 100 feet. Drifting buoys were also 

 deployed on various occasions from these aircraft. 



More than 28 operational missions were flown by the USCG for oil mapping 

 and in partial response to scientific requests, accounting for more than 114 

 hours of air time. The true value of this response to the research effort 

 cannot be estimated, but without USCG logistic support studies of physical 

 processes would have been marginal or nonexistent. 



NASA overflights were conducted on December 19 and 22, 1976, and on 

 January 3, 5, and 6, 1977, under the general direction of J. Mugler, Langley 

 Research Center (LRC) , NASA. Table VII-1 (in Appendix VII) presents the 

 flight log for the December 19 overflight and Figure 2-1 shows the flight 

 lines. The flight log for the NASA overflight on December 22, 1976, is shown 

 in Table VII-2 and the flight lines are shown in Figure VII-1. The flight 

 logs and flight lines for the NASA overflights on January 3, 5, and 6 are 

 shown in Tables VII-3 to VII-5 and Figures VII-2 to VII-4. 



Imagery was obtained from the Landsat II satellite during overpasses 

 near the grounded tanker on December 22 and 23, 1976, and on January 9, 1977. 

 Maps showing the approximate ground coverage expected for these images are 

 presented in Figures VII-5 and VII-6. On December 22, 1976, cloud cover was 



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