AIAA - Online Access to AIAA Meeting Papers
NTRS (NASA Technical Reports Server) - Searchable database of technical reports produced by NASA, as well as other agencies, such as BioMed Central, Aeronautical Research Council (UK), arXiv Physics Eprint Server, and Energy Citation Database (OSTI)). Coverage includes research reports, journal articles, conference and meeting papers, technical videos, mission-related operational documents, and preliminary data. Check the detail coverage here.
GTRS - Goddard Technical reports server
NACA Digital Library - National Advisory Committee for Aeronautics Technical Reports (1917 - 1958, fulltext)
NTIS (Search Technical Reports Collection from 1990 to the Present) - The National Technical Information Service(NTIS) serves as the largest central resource for US government-funded scientific, technical, engineering, and business related information available today. Here you will find information on more than 600,000 information products covering over 350 subject areas from over 200 federal agencies.
AGARD Reports (fulltext)
Wright Air Development Center Digital Collection - 1952-1961. Permanent digital repository for WADC/WADD technical reports issued by the Wright Air Development Center/Division. Provides bibliographic info for reports not available electronically & some historical background

Standards

Patents

Derwent Innovations Index
Delphion - NAL Users Only. Contact 6083/6085 for 'User Name', 'Password' and 'Full-text' downloading.
CSIR Patent search - Council of Scientific and Industrial Research, India
IEC - International Eletrotechnical Commission
Indian Patents
JIS - Japanese Industrial Standard
US Patents - United States Patent and Trademrak Office (full-text)
World wide patent search
European Patent Search