Narrative:

1946 aeronca 7AC fitted with federal 1500 metal skis. Both the bungee and the safety cable are attached to the front of the ski with the same bolt. On the right ski, this bolt failed on takeoff from a frozen lake resulting in the ski tip hanging straight down and aft to the point where the rear cable became taught. (Ski continued to swing from these 2 position). Landing was made at home base airfield (3000 ft grass with approximately 4 inches ice and snow) landing in a slip to land on the left ski first. Landing was smooth and straight until ground speed was very slow at which point the aircraft turned to the right approximately 90 degrees due to the inverted ski tip digging into the ice and snow packed runway. At this point the tail came up enough to catch the propeller and bend both tips. The ski is repairable although bent. No other damage occurred. This pilot recommends that the bungee and safety cable be attached to the ski with separate hard points thus making it truly redundant. Callback conversation with reporter revealed the following information: the reporter says that when the landed at his home base (2b9) he was aided by having a passenger in the rear seat. The extra weight aft from going further onto its nose. As it turned out the propeller had to be replaced, but there was very little other damage. The ski was easily repaired and again there were no injuries. There are a # of ski equipped aircraft at 2b9 that use the same or similar make skis and some of the act had a single hard point mount as the reporter's aircraft did in this incident. Almost everyone at the reporter's suggestion has changed to a 2 hard point mounting system.

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Original NASA ASRS Text

Title: ACFT EQUIP PROB - THE R-HAND SKI MOUNTING BOLT FAILED ON TKOF FROM A FROZEN LAKE AND ON LNDG AT THE PLT'S HOME ARPT THE BROKEN SKI CAUSED THE ACFT TO DAMAGE ITS PROP.

Narrative: 1946 AERONCA 7AC FITTED WITH FEDERAL 1500 METAL SKIS. BOTH THE BUNGEE AND THE SAFETY CABLE ARE ATTACHED TO THE FRONT OF THE SKI WITH THE SAME BOLT. ON THE R SKI, THIS BOLT FAILED ON TKOF FROM A FROZEN LAKE RESULTING IN THE SKI TIP HANGING STRAIGHT DOWN AND AFT TO THE POINT WHERE THE REAR CABLE BECAME TAUGHT. (SKI CONTINUED TO SWING FROM THESE 2 POS). LNDG WAS MADE AT HOME BASE AIRFIELD (3000 FT GRASS WITH APPROX 4 INCHES ICE AND SNOW) LNDG IN A SLIP TO LAND ON THE L SKI FIRST. LNDG WAS SMOOTH AND STRAIGHT UNTIL GND SPD WAS VERY SLOW AT WHICH POINT THE ACFT TURNED TO THE R APPROX 90 DEGS DUE TO THE INVERTED SKI TIP DIGGING INTO THE ICE AND SNOW PACKED RWY. AT THIS POINT THE TAIL CAME UP ENOUGH TO CATCH THE PROP AND BEND BOTH TIPS. THE SKI IS REPAIRABLE ALTHOUGH BENT. NO OTHER DAMAGE OCCURRED. THIS PLT RECOMMENDS THAT THE BUNGEE AND SAFETY CABLE BE ATTACHED TO THE SKI WITH SEPARATE HARD POINTS THUS MAKING IT TRULY REDUNDANT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR SAYS THAT WHEN THE LANDED AT HIS HOME BASE (2B9) HE WAS AIDED BY HAVING A PAX IN THE REAR SEAT. THE EXTRA WT AFT FROM GOING FURTHER ONTO ITS NOSE. AS IT TURNED OUT THE PROP HAD TO BE REPLACED, BUT THERE WAS VERY LITTLE OTHER DAMAGE. THE SKI WAS EASILY REPAIRED AND AGAIN THERE WERE NO INJURIES. THERE ARE A # OF SKI EQUIPPED ACFT AT 2B9 THAT USE THE SAME OR SIMILAR MAKE SKIS AND SOME OF THE ACT HAD A SINGLE HARD POINT MOUNT AS THE RPTR'S ACFT DID IN THIS INCIDENT. ALMOST EVERYONE AT THE RPTR'S SUGGESTION HAS CHANGED TO A 2 HARD POINT MOUNTING SYS.

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.