The Tost tow release system talks about 10,000 operations (Tost terminology) or actuations (FAA) vs 2,000 starts (Tost) or launches (FAA).

What constitutes an operation or actuation? Why are there five times as many (typically) as launches/starts?

http://www.faa.gov/documentLibrary/m...2043.13-2B.pdf
para 808.b

http://www.tost.de/EBugHeckkupplungen.html
Paragraph on maintenance to tow releases.