THIS IS A RPT ABOUT AN AIRLINE'S DC9 ACFT DISCHARGING STATIC ELECTRICITY TO PERSONNEL AND EQUIP AT PTK.

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THIS IS TO ADVISE YOU OF A PROB THAT MAY EXIST AT MANY ARPTS AND COULD POTENTIALLY CAUSE DAMAGE. WE HAVE RPTED IT TO THE FAA BUT ARE PROVIDING INFO TO NASA ALSO SO THAT IT CAN BE DISSEMINATED. OVER THE LAST 6 MONTHS; OUR AIRLINE HAS EXPERIENCED DIFFICULTIES WITH ARCING. IT OCCURRED INTERMITTENTLY BTWN OUR DC9 ACFT AND WHATEVER COMES INTO NEAR CONTACT WITH THEM WHEN THEY ARE PARKED ON THE RAMP. IT SEEMS TO HAPPEN ON ONE ACFT MORE THAN THE REST. WE DID EXTENSIVE TROUBLESHOOTING. THE PROB WOULD GO AWAY; ONLY TO RECUR A MONTH OR 2 LATER. FINALLY WE BEGAN TO SEE A PATTERN IN THE ARPT WHERE THIS OCCURRED; RATHER THAN IN WHICH DC9. MOST CONSISTENTLY; IT OCCURRED ON A NEWLY SURFACED RAMP ON THE OAKLAND-PONTIAC ARPT IN PONTIAC; MI. AFTER THE MOST RECENT INCIDENT THERE; WE FOUND THAT WE COULD NOT DUPLICATE THE PROB AT OUR MAINT FACILITY. SUBSEQUENTLY; OUR DIRECTOR OF MAINT HAD THE RECENTLY ARCING DC9 TOWED ONTO LARGE SHEETS OF PLEXIGLAS SO THAT THE TIRES WERE NOT ABLE TO GND TO THE RAMP AT ANY POINT. THE APU WAS STARTED AND AN AIR CONDITIONING PACK WAS SWITCHED ON. IN THIS CONFIGN; THE DC9 WOULD GENERATE A 4 INCH ARC BTWN IT AND WHATEVER OR WHOEVER CAME CLOSE ENOUGH. OUR DIRECTOR OF MAINT WENT ON TO HAVE 3 MORE OF OUR DC9 ACFT TOWED ONTO THE PLEXIGLAS; AND THE APU AND AIR CONDITIONING PACKS RUN. IN ALL 3 ACFT; THE ARCING WAS DUPLICATED. APPARENTLY; THE ROTATION OF APU AND PACKS GENERATES THE STATIC ELECTRICITY. WE CONTACTED THE OAKLAND-PONTIAC ARPT ASSISTANT ARPT MGR AND TOLD HIM OUR FINDINGS. HE TOLD US THAT THE RAMP SHOULD BE GNDED BUT THAT HE WOULD CHK IT OUT. HE ALSO TOLD US THAT THE RAMP IN QUESTION AT PONTIAC IS MADE UP OF AN FAA APPROVED STANDARD MIX BUT THE 'BINDER' IS A LIQUID SYNTHETIC. HE METERED THE PONTIAC RAMP AND FOUND IT WAS NOT GNDED. TO PROVIDE A GND; HE HAD 4 COPPER RODS DRIVEN INTO THE RAMP AND HAD IT RETESTED. THIS TEST SHOWED THAT THE RAMP IS NOW GNDED. WE TOOK A DC9 TO PONTIAC; PARKED ON THIS RAMP WITH THE APU AND AIR CONDITIONING PACKS RUNNING AND THERE WAS NO ARCING. WE DID NOT FIND IT NECESSARY TO CONNECT A GND WIRE TO ANY OF THE COPPER RODS TO ACHIEVE THIS RESULT. REVIEWING OUR DATA; NOW KNOWING WHAT CAUSES THE ARCING; MAKES US BELIEVE THAT THIS IS NOT AN ISOLATED INCIDENT. THE ARCING HAS ALSO OCCURRED WITH OUR DC9'S ON A RAMP AT GREENVILLE; SC. I HAVE ANECDOTAL INFO THAT IT MAY HAVE ALSO OCCURRED AT SYRACUSE; NY. IT APPEARS POSSIBLE THAT THERE IS SOME PRODUCT THAT IS BEING USED IN RAMP CONSTRUCTION THAT ENHANCES DURABILITY BUT LIMITS OR ELIMINATES GNDING. OUR CONCERN IS THAT THE ARCING COULD POTENTIALLY CAUSE INJURIES OR EVEN DEATHS. WITHOUT A GND; A FUEL TRUCK EVEN WHEN BONDED TO THE AIRPLANE MIGHT CAUSE OR RECEIVE ENOUGH ARC TO START AN EXPLOSION OR FIRE. SOMEONE WITH A HEART CONDITION; WORKING AROUND AN UNGNDED AIRPLANE MAY BE EXPOSED TO ENOUGH OF A JOLT TO CAUSE A HEART ATTACK. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR SAID THAT THE AIRLINE'S PRINCIPAL OPS INSPECTOR HAD BEEN ADVISED OF THE PROB AND HE IN TURN ADVISED AN ENGINEER WITH THE FAA. THIS ENGINEER WAS WITH THE ARPTS GROUP OR PERHAPS IN THEIR FACILITIES CONSTRUCTION OVERSIGHT GROUP; THE RPTR DID NOT KNOW. THE ARPT MGMNT AT PTK HAS NOW HAD 4 LARGE GNDING POSTS DRIVEN INTO THE RAMP WHERE THE COMPANY PARKS THEIR DC9'S AND THIS HAS ELIMINATED THE ARCING PROB. THE RPTR SAID THAT THE COMPANY IS STILL WORKING WITH SYR AND GSP ARPT PERSONNEL TO SOLVE THIS PROB. THE AIRLINE REMOVED OR SIMPLY DID NOT REPLACE THE GNDING STRIPS THAT USED TO BE ATTACHED TO THE MAIN LNDG GEAR SOME TIME AGO BASED ON A FINDING THAT THEY WERE NO LONGER NECESSARY BECAUSE THE ACFT TIRES ARE CONDUCTIVE; SO THIS WAS NOT THE PROB. ALSO THE NEW RAMP BINDER WOULD STILL HAVE ACTED AS AN INSULATOR REGARDLESS OF THE ACFT EQUIP; ACCORDING TO THE RPTR. ANOTHER FACET TO THIS PROB; ACCORDING TO THE RPTR; IS THAT THIS PHENOMENA ONLY SEEMS TO OCCUR TO AIRLINERS AND ONLY WHEN THE APU IS OPERATING AND THE AIR CONDITIONING IS ON. THIS DOES NOT HAPPEN TO SMALL GA ACFT. THERPTR'S THEORY IS THAT THE ROTATION OF THE PWR UNIT AND THE AIR CONDITIONING PACKS AIR CYCLE MACHINE CAUSES A BUILD-UP OF HIGH VOLTAGE STATIC ELECTRICAL DIFFERENTIAL.