Narrative:

During an approach for a rope drop and landing after a glider aeronautical operation, the tow plane pilot allowed the tow rope to contact a power line at the approach end of the runway. At contact with the line, the rope broke and a normal landing was accomplished. Aside from a broken tow rope, inspections revealed no damage to the tow plane or the power line. However, the scenario could have obviously been quite different. Chain of events: the flight had 2 purposes: 1) to determine how well a new tow plane would aeronautical tow a single-place and 2-PLACE glider. The aircraft was recently purchased new as a tow plane and equipped in such a manner to accomplish the task and this flight was the first flight during which a glider was towed. 2) to check local tow pilots out in the aircraft. The flight was thoroughly briefed with an emphasis on takeoff abort points and procedures for the glider and tow plane. A light weight single-place glider was chosen for the first tow to ensure the tow plane performance was more than adequate for the task. The tow pilot was experienced in the local area and the aircraft chkout instructor was familiar with the airport, but had not flown a tow operation at the airport. Takeoff and tow was normal indicating the tow plane had excellent performance. After glider release, the flight consisted of aircraft familiarity training including stalls, slow flight, steep turn, emergency procedures training, etc. Pattern and initial approach to the runway were normal. On short final, the aircraft descended below a normal glide path and the tow line contacted the power line. The normal procedure during glider operations is to approach the glider staging area, drop the rope in a designated clear zone, and continue the landing followed by a taxi back for another glider hook-up and tow. Contributing factors: a different aircraft. The sight picture over the nose of the new tow plane was different from the C182 tow plane familiar to both pilots. The chkout pilot had maule experience while the pilot at the controls had none. Tow release lever placement in the cockpit was in a different position than the PF was used to. While not determined, this could have been distracting or at least occupying a portion of the pilot's thought process during short final. The runway slopes downhill away from the approach end of the runway, creating the possibility of a visual illusion, which might allow the approaching pilot to think he is at a safe altitude when he is actually too low. In fact, the runway has been displaced from the original approach end where the rope drop area is located. The initial takeoff and tow was thoroughly briefed as a new procedure, however, other aspects of the tow operations, specifically approach to landing with the tow rope, were briefed as a normal procedure when perhaps the above mentioned contributing factors should have been included in the briefing.

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Original NASA ASRS Text

Title: DURING CHKOUT IN A MAULE MT7 GLIDER TOWING ACFT, THE TOW ROPE CONTACTED A PWR LINE DURING SHORT FINAL CAUSING THE ROPE TO BREAK. THE ACFT LANDED SAFELY WITHOUT DAMAGE TO ANY PROPERTY, INCLUDING THE PWR LINE OR PERSONS.

Narrative: DURING AN APCH FOR A ROPE DROP AND LNDG AFTER A GLIDER AERO OP, THE TOW PLANE PLT ALLOWED THE TOW ROPE TO CONTACT A PWR LINE AT THE APCH END OF THE RWY. AT CONTACT WITH THE LINE, THE ROPE BROKE AND A NORMAL LNDG WAS ACCOMPLISHED. ASIDE FROM A BROKEN TOW ROPE, INSPECTIONS REVEALED NO DAMAGE TO THE TOW PLANE OR THE PWR LINE. HOWEVER, THE SCENARIO COULD HAVE OBVIOUSLY BEEN QUITE DIFFERENT. CHAIN OF EVENTS: THE FLT HAD 2 PURPOSES: 1) TO DETERMINE HOW WELL A NEW TOW PLANE WOULD AERO TOW A SINGLE-PLACE AND 2-PLACE GLIDER. THE ACFT WAS RECENTLY PURCHASED NEW AS A TOW PLANE AND EQUIPPED IN SUCH A MANNER TO ACCOMPLISH THE TASK AND THIS FLT WAS THE FIRST FLT DURING WHICH A GLIDER WAS TOWED. 2) TO CHK LCL TOW PLTS OUT IN THE ACFT. THE FLT WAS THOROUGHLY BRIEFED WITH AN EMPHASIS ON TKOF ABORT POINTS AND PROCS FOR THE GLIDER AND TOW PLANE. A LIGHT WT SINGLE-PLACE GLIDER WAS CHOSEN FOR THE FIRST TOW TO ENSURE THE TOW PLANE PERFORMANCE WAS MORE THAN ADEQUATE FOR THE TASK. THE TOW PLT WAS EXPERIENCED IN THE LCL AREA AND THE ACFT CHKOUT INSTRUCTOR WAS FAMILIAR WITH THE ARPT, BUT HAD NOT FLOWN A TOW OP AT THE ARPT. TKOF AND TOW WAS NORMAL INDICATING THE TOW PLANE HAD EXCELLENT PERFORMANCE. AFTER GLIDER RELEASE, THE FLT CONSISTED OF ACFT FAMILIARITY TRAINING INCLUDING STALLS, SLOW FLT, STEEP TURN, EMER PROCS TRAINING, ETC. PATTERN AND INITIAL APCH TO THE RWY WERE NORMAL. ON SHORT FINAL, THE ACFT DSNDED BELOW A NORMAL GLIDE PATH AND THE TOW LINE CONTACTED THE PWR LINE. THE NORMAL PROC DURING GLIDER OPS IS TO APCH THE GLIDER STAGING AREA, DROP THE ROPE IN A DESIGNATED CLR ZONE, AND CONTINUE THE LNDG FOLLOWED BY A TAXI BACK FOR ANOTHER GLIDER HOOK-UP AND TOW. CONTRIBUTING FACTORS: A DIFFERENT ACFT. THE SIGHT PICTURE OVER THE NOSE OF THE NEW TOW PLANE WAS DIFFERENT FROM THE C182 TOW PLANE FAMILIAR TO BOTH PLTS. THE CHKOUT PLT HAD MAULE EXPERIENCE WHILE THE PLT AT THE CTLS HAD NONE. TOW RELEASE LEVER PLACEMENT IN THE COCKPIT WAS IN A DIFFERENT POS THAN THE PF WAS USED TO. WHILE NOT DETERMINED, THIS COULD HAVE BEEN DISTRACTING OR AT LEAST OCCUPYING A PORTION OF THE PLT'S THOUGHT PROCESS DURING SHORT FINAL. THE RWY SLOPES DOWNHILL AWAY FROM THE APCH END OF THE RWY, CREATING THE POSSIBILITY OF A VISUAL ILLUSION, WHICH MIGHT ALLOW THE APCHING PLT TO THINK HE IS AT A SAFE ALT WHEN HE IS ACTUALLY TOO LOW. IN FACT, THE RWY HAS BEEN DISPLACED FROM THE ORIGINAL APCH END WHERE THE ROPE DROP AREA IS LOCATED. THE INITIAL TKOF AND TOW WAS THOROUGHLY BRIEFED AS A NEW PROC, HOWEVER, OTHER ASPECTS OF THE TOW OPS, SPECIFICALLY APCH TO LNDG WITH THE TOW ROPE, WERE BRIEFED AS A NORMAL PROC WHEN PERHAPS THE ABOVE MENTIONED CONTRIBUTING FACTORS SHOULD HAVE BEEN INCLUDED IN THE BRIEFING.

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.