Narrative:

The flight was conducted in a PA31-350. Upon arrival at the uncontrolled airport an overflt was conducted to determine runway condition and wind. An entry into left traffic was made and the before landing checks were commenced. For some reason, distraction or whatever, the gear-down check was not made. On close proximity to the runway surface the gear unsafe horn sounded. With the rate of descent and a 4-6 degree upslope runway, recovery was attempted, but was unsuccessful. The aircraft was landed gear up. There was little damage and no injuries due to snow and ice on the runway. The PA31-350 is equipped with a gear horn that sounds when either or both engines go below 12 inches of manifold pressure and the gear is not down and locked. This is inadequate warning of unsafe gear when on approachs that require higher power setting due to high gross weight or gusty condition. Our PA31's were just increased to landing weight of 7368 pounds from 7000 pounds with vortex generators and gear modifications. On beechcraft light twins the gear horn sounds when flaps are brought below 15-20 degrees without the gear down and locked, in addition to the throttles. This provides adequate time to recover or simply lower the gear and continue. The simple addition of the gear warning being tied to the flap system would have prevented this mishap and another that occurred in this area 3 months prior (not to me). To retrofit should be looked into for this twin.

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Original NASA ASRS Text

Title: AN ACR PLT LANDS HIS PA31-350 GEAR UP ON A SNOW COVERED RWY WITH LITTLE DAMAGE AND NO INJURIES.

Narrative: THE FLT WAS CONDUCTED IN A PA31-350. UPON ARR AT THE UNCTLED ARPT AN OVERFLT WAS CONDUCTED TO DETERMINE RWY CONDITION AND WIND. AN ENTRY INTO L TFC WAS MADE AND THE BEFORE LNDG CHKS WERE COMMENCED. FOR SOME REASON, DISTR OR WHATEVER, THE GEAR-DOWN CHK WAS NOT MADE. ON CLOSE PROX TO THE RWY SURFACE THE GEAR UNSAFE HORN SOUNDED. WITH THE RATE OF DSCNT AND A 4-6 DEG UPSLOPE RWY, RECOVERY WAS ATTEMPTED, BUT WAS UNSUCCESSFUL. THE ACFT WAS LANDED GEAR UP. THERE WAS LITTLE DAMAGE AND NO INJURIES DUE TO SNOW AND ICE ON THE RWY. THE PA31-350 IS EQUIPPED WITH A GEAR HORN THAT SOUNDS WHEN EITHER OR BOTH ENGS GO BELOW 12 INCHES OF MANIFOLD PRESSURE AND THE GEAR IS NOT DOWN AND LOCKED. THIS IS INADEQUATE WARNING OF UNSAFE GEAR WHEN ON APCHS THAT REQUIRE HIGHER PWR SETTING DUE TO HIGH GROSS WT OR GUSTY CONDITION. OUR PA31'S WERE JUST INCREASED TO LNDG WT OF 7368 LBS FROM 7000 LBS WITH VORTEX GENERATORS AND GEAR MODIFICATIONS. ON BEECHCRAFT LIGHT TWINS THE GEAR HORN SOUNDS WHEN FLAPS ARE BROUGHT BELOW 15-20 DEGS WITHOUT THE GEAR DOWN AND LOCKED, IN ADDITION TO THE THROTTLES. THIS PROVIDES ADEQUATE TIME TO RECOVER OR SIMPLY LOWER THE GEAR AND CONTINUE. THE SIMPLE ADDITION OF THE GEAR WARNING BEING TIED TO THE FLAP SYS WOULD HAVE PREVENTED THIS MISHAP AND ANOTHER THAT OCCURRED IN THIS AREA 3 MONTHS PRIOR (NOT TO ME). TO RETROFIT SHOULD BE LOOKED INTO FOR THIS TWIN.

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.