Douglas Aircraft Co., Inc. Santa Monica, Calif., U.S.A. Engineering Dept. Technical Data Report No. 1692 on Door Moulding and Plexiglas Tests Modal P-24-3 5-17-37 [May 17, 1937]. 10 pages of text, 6 plates Total 16 pages [actual umber of pages in report 23 as there are handwritten notes at end]. Prepared by N. J. denTex. Part I Test on Door Molding - feasibility study for a self-sealing molding of outward opening doors. Rubber used was Wall Goodrich Rubber Grade 780. Pure gum rubber sheet was Kirkhill Company Grade 500-A. Test to Determine Lower Temperature Limit at Which the Door Seal is Satisfactory. Conclusion: while -55F degrees may be low, seal will act properly at -45F degrees. Part II Tests on Porthole with Plexiglas. Usefulness of Plexiglas disk (free diameter 12”, thickness .400) in a rubber molding as self-sealing; cold test; supplementary tests; Conclusions: Plexiglass appears satisfactory, rubber channel and window frame seal remain tight. Part IV Second Test with ⅜ Plexiglas. cold condition only. Part V Cold Test with .500 Plexiglas. higher the pressure is, the smaller the pieces into which the plexiglas breaks. Part VII Tests on ⅛ Plexiglas. ⅛ plexiglas is ideal thickness for windows of 12” diameter. Two blueprint Figures, 4 black and white photographs - 8 x 10”, 4 pages handwritten Summary Conclusions , 1937

Douglas Aircraft Co., Inc. Santa Monica, Calif., U.S.A. Engineering Dept. Technical Data Report No. 1692 on Door Moulding and Plexiglas Tests Modal P-24-3 5-17-37 [May 17, 1937]. 10 pages of text, 6 plates Total 16 pages [actual umber of pages in report 23 as there are handwritten notes at end]. Prepared by N. J. denTex. Part I Test on Door Molding - feasibility study for a self-sealing molding of outward opening doors. Rubber used was Wall Goodrich Rubber Grade 780. Pure gum rubber sheet was Kirkhill Company Grade 500-A. Test to Determine Lower Temperature Limit at Which the Door Seal is Satisfactory. Conclusion: while -55F degrees may be low, seal will act properly at -45F degrees. Part II Tests on Porthole with Plexiglas. Usefulness of Plexiglas disk (free diameter 12”, thickness .400) in a rubber molding as self-sealing; cold test; supplementary tests; Conclusions: Plexiglass appears satisfactory, rubber channel and window frame seal remain tight. Part IV Second Test with ⅜ Plexiglas. cold condition only. Part V Cold Test with .500 Plexiglas. higher the pressure is, the smaller the pieces into which the plexiglas breaks. Part VII Tests on ⅛ Plexiglas. ⅛ plexiglas is ideal thickness for windows of 12” diameter. Two blueprint Figures, 4 black and white photographs - 8 x 10”, 4 pages handwritten Summary Conclusions , 1937, MS0416.03, Item: 3. Matthew Currie Collection, SC MS0416. Lehigh University Special Collections. https://archivesspace.lib.lehigh.edu//repositories/3/archival_objects/132686 Accessed May 19, 2026.