Volume 42, Issue 3 (May 1997)
Field Sampling and Chemical Analysis
The mass of material plugging the B2 elbow was 4.1 mm in diameter and 0.6 mm thick. It consisted of both light and dark colored organic material mixed with stellate trichomes and the pollen of several plants found near where the aircraft wreckage was stored. The mass was colonized by fungi such as Alternaria and Cladosporium. The organic matrix consisted of two dissimilar materials: A dark “gum-like” material and a lighter, golden-colored “nectar” and was subjected to FT-infrared (FTIR) spectroscopic analyses. Both reflectance and transmission FTIR techniques were used in the analyses, but the best results were obtained from transmission FTIR. This required that opaque substances such as the organic matrix be prepared as thin films. Several materials were collected from near the storage site as reference materials and these were also analyzed by FTIR spectroscopy. The reference materials included leaf and sap from Sphaeralcea coccinea and Grindelia squarrosa growing around the storage site. Commercial honey, cleaning solvents, and other organic fluids used in the aviation industry were also analyzed as well as gummy deposits found in equipment unrelated to the aircraft wreckage but stored near the aircraft parts. Mixed FTIR spectra were obtained from the organic matrix found in the B2 elbow, but showed a significant carbohydrate component. Comparison of these spectra to the reference materials clearly showed that the organic matrix was composed of macerated Sphaeralcea leaves mixed with a honey-like nectar.