Report - AC 91-66 - Noise Abatement for HelicoptersAC 91-66 6/4/87 d. Landings on grass or dirt areas are better than hard surfaces such as concrete. Tte soft path Oller which sound travels

Select PornographicDefamatoryIllegal/UnlawfulSpamOther Terms Of Service ViolationFile a copyright complaint

Please pass captcha verification before submit form