Narrative:

I was driving the tug, there were wing walkers, and I was riding the brakes. I was positioning aircraft X in order to chalk out lead-in lines and stop lines on the floor. Since hangar construction, there are no lines painted on the floor as to where to position aircraft. We were moving the aircraft in and out to find a suitable spot. On the fourth time backing into position, moving aircraft 1 ft over (east) so we could get a second aircraft in, we struck a suspension cable for the recently installed safety harness system. The cable wedged between the top of the rudder and below the vertical tip fairing and tore through the rudder vertically downward 1 ft. As I heard the tear, the tug was stopped. The main struts were 4 inches higher than normal and the fact that this cable system and support angle is about 3 ft below the ht of the tail, there is no way to judge ht of cables from ground due to fact that they blend in with ceiling. The wing walkers were concerned with the wings hitting the wall and the tail hitting the wall. The aircraft wing (left) just entered the building with more than 5 ft of clearance from the tip. We were not in an abnormal parking position, the nose gear was outside on the downslope of the hangar ramp. When we park an aircraft in a hangar, we should not be worried about hitting anything that is hanging from the ceiling because from the ground looking 90 ft up at a 1/4 inch cable, you have no depth perception as to where it lies in relation to the ht of the tail.

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Original NASA ASRS Text

Title: A B737-700 BEING BACKED INTO A NEW HANGAR FOR POSITIONING FIT FOR STRIPING OF THE FLOOR STRUCK A HARNESS SAFETY CABLE INCURRING DAMAGE TO THE RUDDER.

Narrative: I WAS DRIVING THE TUG, THERE WERE WING WALKERS, AND I WAS RIDING THE BRAKES. I WAS POSITIONING ACFT X IN ORDER TO CHALK OUT LEAD-IN LINES AND STOP LINES ON THE FLOOR. SINCE HANGAR CONSTRUCTION, THERE ARE NO LINES PAINTED ON THE FLOOR AS TO WHERE TO POS ACFT. WE WERE MOVING THE ACFT IN AND OUT TO FIND A SUITABLE SPOT. ON THE FOURTH TIME BACKING INTO POS, MOVING ACFT 1 FT OVER (E) SO WE COULD GET A SECOND ACFT IN, WE STRUCK A SUSPENSION CABLE FOR THE RECENTLY INSTALLED SAFETY HARNESS SYS. THE CABLE WEDGED BTWN THE TOP OF THE RUDDER AND BELOW THE VERT TIP FAIRING AND TORE THROUGH THE RUDDER VERTLY DOWNWARD 1 FT. AS I HEARD THE TEAR, THE TUG WAS STOPPED. THE MAIN STRUTS WERE 4 INCHES HIGHER THAN NORMAL AND THE FACT THAT THIS CABLE SYS AND SUPPORT ANGLE IS ABOUT 3 FT BELOW THE HT OF THE TAIL, THERE IS NO WAY TO JUDGE HT OF CABLES FROM GND DUE TO FACT THAT THEY BLEND IN WITH CEILING. THE WING WALKERS WERE CONCERNED WITH THE WINGS HITTING THE WALL AND THE TAIL HITTING THE WALL. THE ACFT WING (L) JUST ENTERED THE BUILDING WITH MORE THAN 5 FT OF CLRNC FROM THE TIP. WE WERE NOT IN AN ABNORMAL PARKING POS, THE NOSE GEAR WAS OUTSIDE ON THE DOWNSLOPE OF THE HANGAR RAMP. WHEN WE PARK AN ACFT IN A HANGAR, WE SHOULD NOT BE WORRIED ABOUT HITTING ANYTHING THAT IS HANGING FROM THE CEILING BECAUSE FROM THE GND LOOKING 90 FT UP AT A 1/4 INCH CABLE, YOU HAVE NO DEPTH PERCEPTION AS TO WHERE IT LIES IN RELATION TO THE HT OF THE TAIL.

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.