Narrative:

While sitting in parked aircraft, landing helicopter's downwash caused 1 rotor blade parked in 2 O'clock position to strike the ground. Visual inspection by crew found some damage to blade. A manufacturer's maintenance representative was flown in to inspect the rotor head and all blades and aircraft was found to be airworthy. The aircraft was flown back to home base. The landing helicopter, also an small transport, was landing with a slight quartering tailwind to a very confined parking spot. There was an aircraft parked right on the other side also! Callback conversation with reporter revealed the following information: reporter states the disturbing and downright scary thing about this is that had they not been sitting in the helicopter, they might not have been aware of the damage. This was at night and the preflight inspection would not have been detailed enough to spot the split in the rotor blade. Reporter did not see the approach path of the helicopter so does not know if he was hover taxiing into parking or if he made an overhead approach. There was a tailwind which may have required more power usage than normal. Reporter's chief pilot is manager of the safety round table for helicopter operators and has certainly made this problem known to this group. Another corp aircraft had same thing happen recently so industry is being made aware of possible problem. Reporter states the only thing he might have done differently was to request a ferry permit to return aircraft to home base. He was told it was airworthy but has a question in his mind about proper regulation.

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Original NASA ASRS Text

Title: PARKED CORPORATE HELI EXPERIENCES DOWNWASH FROM LNDG HELI CAUSING BLADE DAMAGE.

Narrative: WHILE SITTING IN PARKED ACFT, LNDG HELI'S DOWNWASH CAUSED 1 ROTOR BLADE PARKED IN 2 O'CLOCK POS TO STRIKE THE GND. VISUAL INSPECTION BY CREW FOUND SOME DAMAGE TO BLADE. A MANUFACTURER'S MAINT REPRESENTATIVE WAS FLOWN IN TO INSPECT THE ROTOR HEAD AND ALL BLADES AND ACFT WAS FOUND TO BE AIRWORTHY. THE ACFT WAS FLOWN BACK TO HOME BASE. THE LNDG HELI, ALSO AN SMT, WAS LNDG WITH A SLIGHT QUARTERING TAILWIND TO A VERY CONFINED PARKING SPOT. THERE WAS AN ACFT PARKED RIGHT ON THE OTHER SIDE ALSO! CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES THE DISTURBING AND DOWNRIGHT SCARY THING ABOUT THIS IS THAT HAD THEY NOT BEEN SITTING IN THE HELI, THEY MIGHT NOT HAVE BEEN AWARE OF THE DAMAGE. THIS WAS AT NIGHT AND THE PREFLT INSPECTION WOULD NOT HAVE BEEN DETAILED ENOUGH TO SPOT THE SPLIT IN THE ROTOR BLADE. RPTR DID NOT SEE THE APCH PATH OF THE HELI SO DOES NOT KNOW IF HE WAS HOVER TAXIING INTO PARKING OR IF HE MADE AN OVERHEAD APCH. THERE WAS A TAILWIND WHICH MAY HAVE REQUIRED MORE PWR USAGE THAN NORMAL. RPTR'S CHIEF PLT IS MGR OF THE SAFETY ROUND TABLE FOR HELI OPERATORS AND HAS CERTAINLY MADE THIS PROB KNOWN TO THIS GROUP. ANOTHER CORP ACFT HAD SAME THING HAPPEN RECENTLY SO INDUSTRY IS BEING MADE AWARE OF POSSIBLE PROB. RPTR STATES THE ONLY THING HE MIGHT HAVE DONE DIFFERENTLY WAS TO REQUEST A FERRY PERMIT TO RETURN ACFT TO HOME BASE. HE WAS TOLD IT WAS AIRWORTHY BUT HAS A QUESTION IN HIS MIND ABOUT PROPER REG.

Data retrieved from NASA's ASRS site as of July 2007 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.