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Sample collection for aircraft exhaust particles. (A). Aircraft used in the study, arrows point to the location of the collecting tube (B). (C) 50 ml tube with glass wool and EM supports (arrows).
Source publication
Piston powered aircraft burning leaded gasoline contribute ∼70% of the lead in the atmosphere in the US. The physical size, composition, and structure of aircraft exhaust particles containing lead dibromide are poorly understood and heretofore have not been examined directly by electron microscopy (EM), in particular when captured from an aircraft...
Contexts in source publication
Context 1
... aircraft used for this study was a 1959 Piper Super Cub with a normally carbureted 160 hp 4 cylinder Lycoming 0-320 engine ( Fig. 1A and B). The airplane was operated on 100 LL fuel. Collection tubes were constructed from 50 ml plastic tubes by drilling holes in the bottom to allow air flow and packing the tubes loosely with glass wool (Fig. 1C). From 4 to 6 carbon covered 400 mesh EM grids were placed in or on top of the glass wool and the tubes capped prior to ...
Context 2
... aircraft used for this study was a 1959 Piper Super Cub with a normally carbureted 160 hp 4 cylinder Lycoming 0-320 engine ( Fig. 1A and B). The airplane was operated on 100 LL fuel. Collection tubes were constructed from 50 ml plastic tubes by drilling holes in the bottom to allow air flow and packing the tubes loosely with glass wool (Fig. 1C). From 4 to 6 carbon covered 400 mesh EM grids were placed in or on top of the glass wool and the tubes capped prior to use. For collection, 3 to 4 tubes were attached to the landing struts of the airplane directly in line with the exhaust gasses and 2 feet from the end of the exhaust pipe (Fig. 1B). The tubes were capped until just ...
Context 3
... and packing the tubes loosely with glass wool (Fig. 1C). From 4 to 6 carbon covered 400 mesh EM grids were placed in or on top of the glass wool and the tubes capped prior to use. For collection, 3 to 4 tubes were attached to the landing struts of the airplane directly in line with the exhaust gasses and 2 feet from the end of the exhaust pipe (Fig. 1B). The tubes were capped until just before takeoff followed by flight at a normal rpm (2400 rpm). The tubes were immediately capped after landing and the EM grids stored in a closed box until ...
Context 4
... directly image particles expelled in the exhaust of a piston powered aircraft in flight using 100 LL gasoline 50 ml plastic tubes were loosely filled with glass wool, and EM supports placed in or on top of the glass wool. The tubes were attached to the outside of a Piper Super Cub ( Fig. 1 A-C), (Materials and Methods). From the 100-mph aircraft speed and the distance between the exhaust pipe and collecting tube, it can be estimated that the exhaust particles could have been trapped on the EM supports within 10-15 ms of exiting the exhaust pipe. ...
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