Narrative:

I was on a low level photo flight for a boat manufacturing company. Power line was unmarked and crossed lake. It was virtually invisible with hills and terrain in the background. Main rotor struck power line, severing it. Helicopter was still flying and I was able to land it safely. No injuries. Should have markers on line to make it visible. Callback conversation with reporter revealed the following: reporter gave the location of the cable as being stretched across 'the big creek arm of table rock lake,' and further said it is just west of a large vacation resort establishment on that cove/tributary. The cable has been replaced since the accident and is still unmarked. The aircraft involved had damage to the main rotor and main frame totally over $30000, so the FAA has classified this as an accident. No injuries, however. The presence of the cable is not indicated on local charts or information sheets used by airmen in the area, and is not indicated on the kc VFR chart. Reporter says there are several other cables across tributary bodies of water at that lake and there had been a prior accident similar to this one involving another cable a short time before this one. He also noted that the corps of engineers requires that cables stretched across the main body of the lake be marked, but that this is apparently not required for tributaries. The FAA has awarded reporter a 30 day suspension for careless flying. He concedes that he should have been more careful, but reiterates that, from a low altitude, the cables are absolutely invisible against the terrain background.

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Original NASA ASRS Text

Title: SMA HELICOPTER ON LOW LEVEL PHOTO MISSION ACROSS A LAKE HITS UNMARKED CABLE STRETCHED ACROSS LAKE.

Narrative: I WAS ON A LOW LEVEL PHOTO FLT FOR A BOAT MANUFACTURING COMPANY. PWR LINE WAS UNMARKED AND CROSSED LAKE. IT WAS VIRTUALLY INVISIBLE WITH HILLS AND TERRAIN IN THE BACKGROUND. MAIN ROTOR STRUCK PWR LINE, SEVERING IT. HELI WAS STILL FLYING AND I WAS ABLE TO LAND IT SAFELY. NO INJURIES. SHOULD HAVE MARKERS ON LINE TO MAKE IT VISIBLE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR GAVE THE LOCATION OF THE CABLE AS BEING STRETCHED ACROSS 'THE BIG CREEK ARM OF TABLE ROCK LAKE,' AND FURTHER SAID IT IS JUST W OF A LARGE VACATION RESORT ESTABLISHMENT ON THAT COVE/TRIBUTARY. THE CABLE HAS BEEN REPLACED SINCE THE ACCIDENT AND IS STILL UNMARKED. THE ACFT INVOLVED HAD DAMAGE TO THE MAIN ROTOR AND MAIN FRAME TOTALLY OVER $30000, SO THE FAA HAS CLASSIFIED THIS AS AN ACCIDENT. NO INJURIES, HOWEVER. THE PRESENCE OF THE CABLE IS NOT INDICATED ON LCL CHARTS OR INFO SHEETS USED BY AIRMEN IN THE AREA, AND IS NOT INDICATED ON THE KC VFR CHART. RPTR SAYS THERE ARE SEVERAL OTHER CABLES ACROSS TRIBUTARY BODIES OF WATER AT THAT LAKE AND THERE HAD BEEN A PRIOR ACCIDENT SIMILAR TO THIS ONE INVOLVING ANOTHER CABLE A SHORT TIME BEFORE THIS ONE. HE ALSO NOTED THAT THE CORPS OF ENGINEERS REQUIRES THAT CABLES STRETCHED ACROSS THE MAIN BODY OF THE LAKE BE MARKED, BUT THAT THIS IS APPARENTLY NOT REQUIRED FOR TRIBUTARIES. THE FAA HAS AWARDED RPTR A 30 DAY SUSPENSION FOR CARELESS FLYING. HE CONCEDES THAT HE SHOULD HAVE BEEN MORE CAREFUL, BUT REITERATES THAT, FROM A LOW ALT, THE CABLES ARE ABSOLUTELY INVISIBLE AGAINST THE TERRAIN BACKGROUND.

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.