Image from (NB: not that I am sure the helicopters flying over my -- our -- neighborhood are military)This heli-hell-copter noise occurs about -- say -- four times a day according to my non-scientific survey, as I work at home on my blog and articles, which require their author a modicum of silence to produce acceptable work.
My latest (of several) calls re this aerial, USA Vietnam War-style noise invasion [Ok, only five too-long ten minutes per overflight, and sans napalm] in the sky of Washington, D.C to the Office of Inspector General (DOT) 1-800-424-9071, resulted in the polite person (who said he was "on contract" with the agency -- no wonder he was so polite?), saying that I should contact: www.ffaa.gov.
BTW, my "complaint" number re the helicopter noise at FAA is: 160302-15. Below my notes on the helicopter flights (I fully stand to be corrected re the exact time).
10:40 (two helicopters)
13:54 (several helicopters)