Narrative:

Aircraft sustained damage to slats when slats were extended on ladders left under leading edge of wing which had been used to check the tops of wing for frost. Air crew arrived at aircraft for preflight. Copilot observed significant frost on trailing edge of wings and also on trailing edge of flaps which were fully extended or dropping from sitting overnight. The hydraulic pumps were off and the flap handle was in the up position. Also, the left trailing edge accumulator low light on overhead panel was illuminated. I checked with operations to see when they wanted to deice. The ramp supervisor advised that of their 6 ramp personnel only 2 had arrived for work that morning. They were behind and would deice during our preflight. Because of the left trailing edge accumulator low message I asked the copilot to clear the flaps and slats and we turned on the hydraulic pumps, the auxiliary and xfer pump, and the flaps retracted. The left accumulator low message extinguished so no maintenance write-up was required. A few mins later, the ramp supervisor arrived and asked us to prepare the aircraft for deicing. He commented on the fact that the flaps had been covered with frost and said he would clear the wings so we could relower the flaps so we could clean off the entire surface. In the cockpit, we concluded that this was the prudent course of action to insure the flaps were completely free of frost. The ramp supervisor was instructed to clear the wings. He proceeded to the area forward of the aircraft. We observed him viewing both sides of the aircraft and he gave us the thumbs up signal as we had briefed. The flap slat handle was placed to the full down position. There was an aircraft jolt as the leading edge devices struck the ladders which had not been removed from under the aircraft wings. Contributing factor: understaffing or short handed on ramp. Aircraft could have been deiced prior to crew arrival.

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Original NASA ASRS Text

Title: AN MD88 WHILE PREPARING FOR DEICING INCURRED DAMAGE TO BOTH WING SLATS CAUSED BY EXTENDING THE LEADING EDGE DEVICES ONTO LADDERS POSITIONED UNDER THE WINGS.

Narrative: ACFT SUSTAINED DAMAGE TO SLATS WHEN SLATS WERE EXTENDED ON LADDERS LEFT UNDER LEADING EDGE OF WING WHICH HAD BEEN USED TO CHK THE TOPS OF WING FOR FROST. AIR CREW ARRIVED AT ACFT FOR PREFLT. COPLT OBSERVED SIGNIFICANT FROST ON TRAILING EDGE OF WINGS AND ALSO ON TRAILING EDGE OF FLAPS WHICH WERE FULLY EXTENDED OR DROPPING FROM SITTING OVERNIGHT. THE HYD PUMPS WERE OFF AND THE FLAP HANDLE WAS IN THE UP POS. ALSO, THE L TRAILING EDGE ACCUMULATOR LOW LIGHT ON OVERHEAD PANEL WAS ILLUMINATED. I CHKED WITH OPS TO SEE WHEN THEY WANTED TO DEICE. THE RAMP SUPVR ADVISED THAT OF THEIR 6 RAMP PERSONNEL ONLY 2 HAD ARRIVED FOR WORK THAT MORNING. THEY WERE BEHIND AND WOULD DEICE DURING OUR PREFLT. BECAUSE OF THE L TRAILING EDGE ACCUMULATOR LOW MESSAGE I ASKED THE COPLT TO CLR THE FLAPS AND SLATS AND WE TURNED ON THE HYD PUMPS, THE AUX AND XFER PUMP, AND THE FLAPS RETRACTED. THE L ACCUMULATOR LOW MESSAGE EXTINGUISHED SO NO MAINT WRITE-UP WAS REQUIRED. A FEW MINS LATER, THE RAMP SUPVR ARRIVED AND ASKED US TO PREPARE THE ACFT FOR DEICING. HE COMMENTED ON THE FACT THAT THE FLAPS HAD BEEN COVERED WITH FROST AND SAID HE WOULD CLR THE WINGS SO WE COULD RELOWER THE FLAPS SO WE COULD CLEAN OFF THE ENTIRE SURFACE. IN THE COCKPIT, WE CONCLUDED THAT THIS WAS THE PRUDENT COURSE OF ACTION TO INSURE THE FLAPS WERE COMPLETELY FREE OF FROST. THE RAMP SUPVR WAS INSTRUCTED TO CLR THE WINGS. HE PROCEEDED TO THE AREA FORWARD OF THE ACFT. WE OBSERVED HIM VIEWING BOTH SIDES OF THE ACFT AND HE GAVE US THE THUMBS UP SIGNAL AS WE HAD BRIEFED. THE FLAP SLAT HANDLE WAS PLACED TO THE FULL DOWN POS. THERE WAS AN ACFT JOLT AS THE LEADING EDGE DEVICES STRUCK THE LADDERS WHICH HAD NOT BEEN REMOVED FROM UNDER THE ACFT WINGS. CONTRIBUTING FACTOR: UNDERSTAFFING OR SHORT HANDED ON RAMP. ACFT COULD HAVE BEEN DEICED PRIOR TO CREW ARRIVAL.

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.