Narrative:

Having listened to the ASOS (winds calm or very light); I approached the airport to land on runway 16. No traffic was heard on unicom. [I] announced my position and intentions. Anonymous voice announced military helicopters hovering to the east well clear of the runway. [I] continued the approach; eventually spotting one of them well to the left of the approach end of runway 16. [I] judged it to be ok to land. Entering the flare; I encountered very significant turbulence. [I] recovered adequately to complete a reasonable landing. With a lifetime of aviation...I'm no stranger to operations in mixed traffic. However; I had obviously not made adequate allowance for the rotor downwash from a hovering helicopter; seemingly quite a distance away and didn't realize how far that downwash can spread out along the ground in light to calm winds. After landing; I learned these were big military H-60's out doing testing on new helicopters. I welcome the military using the civilian airports; but I suggest two things. Perhaps with some liaison with them we can encourage them; when operating at uncontrolled airports; to clearly announce frequently on unicom the type and size of helicopter and potential for hazardous rotor downwash. Also; it may be useful to add a brief caution NOTAM advising of such activity. I've discussed this experience with the FSDO. They also encouraged me to submit it in writing via this report. Perhaps it can save some other pilots some grief!

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Original NASA ASRS Text

Title: C182 pilot in landing flare; encountered rotorwash turbulence from military H60 helicopters operating in the vicinity of the runway at a non-towered airport.

Narrative: Having listened to the ASOS (winds calm or very light); I approached the airport to land on Runway 16. No traffic was heard on UNICOM. [I] announced my position and intentions. Anonymous voice announced military helicopters hovering to the east well clear of the runway. [I] continued the approach; eventually spotting one of them well to the left of the approach end of Runway 16. [I] judged it to be OK to land. Entering the flare; I encountered very significant turbulence. [I] recovered adequately to complete a reasonable landing. With a lifetime of aviation...I'm no stranger to operations in mixed traffic. However; I had obviously not made adequate allowance for the rotor downwash from a hovering helicopter; seemingly quite a distance away and didn't realize how far that downwash can spread out along the ground in light to calm winds. After landing; I learned these were big military H-60's out doing testing on new helicopters. I welcome the military using the civilian airports; but I suggest two things. Perhaps with some liaison with them we can encourage them; when operating at uncontrolled airports; to clearly announce frequently on UNICOM the type and size of helicopter and potential for hazardous rotor downwash. Also; it may be useful to add a brief caution NOTAM advising of such activity. I've discussed this experience with the FSDO. They also encouraged me to submit it in writing via this report. Perhaps it can save some other pilots some grief!

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.