Narrative:

Incident occurred during a weekly undergnd cable patrol along railroad tracks which pass 3 NM north of johnstown- cambria airport (jst). Wbound flight was at an altitude of 300 ft AGL and jst tower was contacted for transition through air traffic area 5 mi northeast of jst. Continuing wbound along tracks, I recorded a cable hazard condition spotted prior to call to jst tower. Approximately 2 mi east of wire crossing, I noted my location and that a power line crossing was around the next bend. During this time I spotted another possible cable hazard and descended, making a 360 degree turn, to assess the site. Determining no hazard, continued along railroad tracks at 300 ft AGL. During this time the aircraft struck a power line crossing the railroad tracks approximately 3 mi northwest of jst. The impact tore the left skid and aft xtube from the aircraft, while the right skid was hanging by the forward xtube only. I then turned toward jst, contacting tower to declare an emergency. After arrival, the right skid was removed and landing was made without further incident or damage to the aircraft. A later aerial inspection at the wire strike site, showed that the detached landing gear section fell to the ground in an area next to the railroad tracks and caused no damage to persons or property on the ground. The FAA investigator classified this as an 'aircraft incident' because there were no injuries, and damage to the aircraft was limited to the landing gear and its attach points. I believe that the incident was caused by a momentary lapse of concentration, most likely due to the aforementioned distrs. To prevent further occurrences, I would stress the need to maintain constant vigilance, particularly in the area of known hazards.

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Original NASA ASRS Text

Title: ROTARY WINGED TFC SUFFERS ACFT DAMAGE TO ITS UNDERCARRIAGE BY CABLE STRIKE IN A LOW ALT CIVIL OP.

Narrative: INCIDENT OCCURRED DURING A WKLY UNDERGND CABLE PATROL ALONG RAILROAD TRACKS WHICH PASS 3 NM N OF JOHNSTOWN- CAMBRIA ARPT (JST). WBOUND FLT WAS AT AN ALT OF 300 FT AGL AND JST TWR WAS CONTACTED FOR TRANSITION THROUGH ATA 5 MI NE OF JST. CONTINUING WBOUND ALONG TRACKS, I RECORDED A CABLE HAZARD CONDITION SPOTTED PRIOR TO CALL TO JST TWR. APPROX 2 MI E OF WIRE XING, I NOTED MY LOCATION AND THAT A PWR LINE XING WAS AROUND THE NEXT BEND. DURING THIS TIME I SPOTTED ANOTHER POSSIBLE CABLE HAZARD AND DSNDED, MAKING A 360 DEG TURN, TO ASSESS THE SITE. DETERMINING NO HAZARD, CONTINUED ALONG RAILROAD TRACKS AT 300 FT AGL. DURING THIS TIME THE ACFT STRUCK A PWR LINE XING THE RAILROAD TRACKS APPROX 3 MI NW OF JST. THE IMPACT TORE THE L SKID AND AFT XTUBE FROM THE ACFT, WHILE THE R SKID WAS HANGING BY THE FORWARD XTUBE ONLY. I THEN TURNED TOWARD JST, CONTACTING TWR TO DECLARE AN EMER. AFTER ARR, THE R SKID WAS REMOVED AND LNDG WAS MADE WITHOUT FURTHER INCIDENT OR DAMAGE TO THE ACFT. A LATER AERIAL INSPECTION AT THE WIRE STRIKE SITE, SHOWED THAT THE DETACHED LNDG GEAR SECTION FELL TO THE GND IN AN AREA NEXT TO THE RAILROAD TRACKS AND CAUSED NO DAMAGE TO PERSONS OR PROPERTY ON THE GND. THE FAA INVESTIGATOR CLASSIFIED THIS AS AN 'ACFT INCIDENT' BECAUSE THERE WERE NO INJURIES, AND DAMAGE TO THE ACFT WAS LIMITED TO THE LNDG GEAR AND ITS ATTACH POINTS. I BELIEVE THAT THE INCIDENT WAS CAUSED BY A MOMENTARY LAPSE OF CONCENTRATION, MOST LIKELY DUE TO THE AFOREMENTIONED DISTRS. TO PREVENT FURTHER OCCURRENCES, I WOULD STRESS THE NEED TO MAINTAIN CONSTANT VIGILANCE, PARTICULARLY IN THE AREA OF KNOWN HAZARDS.

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.