Narrative:

Between the beginning of jun/95 and the middle of oct/95 I have encountered 18 different B727's with between 1 and 3 (out of a total of 6) static port heaters inoperative. A very rough extrapolation from my personal experience indicates possibly 20 plus percent of our own B727 inventory being operated with this problem. On a world-wide basis therefore, the total number could be around 400-500 aircraft. From my encounters, I've determined how to tell in a matter of seconds, from a glance at the pitot-static ammeters, the exact number of heaters which are inoperative, and also, of course, which side of the fuselage they are on. This simple analysis, which is based on the cumulative amperage draw of 3 port heaters per ammeter, is not included in our pilot's operating manual nor, I've been told, is it mentioned in boeing's or our own maintenance pubs. I have addressed this problem through proper company channels with 11 reports. For months now, the official response to me has been, thank you very much, we've spoken with boeing and a fix is in progress. Yet almost every time I fly a trip, I encounter at least one additional B727 with the same problem. And almost every time I write one up, I am told locally that no replacement heaters are in stock. Then, following FAA regulations, either the company dispatcher is able to give me a 'no icing en route' clearance, or (I have assumed, until recently) the plane is grounded until one can be issued. Puzzled by the ongoing problem, I contacted an acquaintance at boeing in aug/95. His confidential response was that they then had only 9 replacement heaters in stock, plus 24 more 'on the way' from a subcontractor. 2 aircraft I'd written up and assumed would be fixed, I later encountered with what appear to be the same static ports unheated. One ship, which had 3 static ports unheated, I found about 2 months later to still have 3 unheated. Another ship had one bad port in jun/95, and almost exactly 3 months later I found it with 2 bad ports. In both cases, on the first go around I neglected to record exactly which ports, but the odds are greatly in favor of them never having been replaced. If so, I don't believe the ignorance is deliberate, a company representative reported to me that in some instances, our maintenance has not believed my write-up was correct. They also have almost no clear guidelines in this area. Many times I've had to joust with mechanics, always understaffed in today's grim deregulatory war-zone of discount airfares, and under pressure to get the planes out, who initially disbelieve me. Some have questioned me even after I took them outside and had them hand-feel the ports. Responses I've gotten: 1) the questionable port heaters are connected to the ground shift mechanism, and will heat up airborne. 2) they are heated, just not as well as the others. (I simply point out how an adjacent hot port, which will scorch a finger in a second, conducts warmth through the aircraft skin to raise the temperature of the dead port a few degrees above the outside air temperature.) 3) if the amber pitot-heat 'off' light is out with the pitot-static switches on, the static ports are all also heated. Clearly, many hundreds of B727's have been operating with these things unheated, in all kinds of WX, all over the world, for yrs. What's been intimated to me, is static port icing is not a problem. Or is it? My company's planes, despite a dramatic curtailment in maintenance staffing, are still probably as sound as any. Yet, I've found as many as half a ship's static ports unheated (in a few cases, both captain's ports or both first officer's ports, thereby eliminating the redundancy factor on one side of the cockpit). I wonder, has boeing done tests to determine just how much icing it takes (on the ground as well as in the air), to plug them up? Using elementary knowledge of relative gaseous pressure (and standing, probably, on very rocky scientific ground), I gather that completely plugged static ports: 1) would cause altimeters to hang up during descent. 2) would cause airspeed indicators to decrease artificially during climb out, as atmospheric pressure decreases. What I am asking of you, is to plug this problem into whatever records you have of B727 controled flight into terrain in possible icing conditions and of B727 upsets while taking off in possible icing conditions. Can you find any connection between this malfunction, and past tragedies or near-disasters? Just how high should the level of concern be? My company seems to have adopted an ambiguous approach to this, as well as a 'hands-off' attitude toward me. For the latter I am thankful, because I know other companies would have made my job (if I still had one) miserable. Nevertheless, the last 4 months have been stressful for me: I feel like the lone ranger, struggling to operate inside a bulging personal envelope of safety, professional ethics, and loyalty to my company. Callback conversation with reporter revealed the following information: the reporter has mounted a crusade within his air carrier to get the static port heaters operating. He has caused many flts to be canceled costing his air carrier many dollars in lost revenue. The reporter, and this analyst, have found cockpit crew persons that merely watch for the ammeter to jump and do not really note that there is a minimum of 1.2 amps showing. The reporter has had to convince mechanics and his air carrier management that all 6 ports must be hot on the ground to be operating properly. He has written an article, under his byline, for his pilot union safety newsletter about this problem. He has had only 1 negative reaction from his air carrier management. In general, he is satisfied with the response from his fellow pilots and his air carrier. He has found 31 ports inoperative on 20 aircraft. This amounts to 15 percent of his air carrier's B727-200 aircraft. The procedure at another air carrier, now out of business, was for the so to turn on the static ports on his preflight inspection, then go outside and feel each one of the 6 to assure that all were hot to the touch. The reporter believes that, because the aircraft are all about 20 yrs old, these heaters are failing world wide and there may be several aircraft flying around with all redundancy lost in the static system.

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Original NASA ASRS Text

Title: NUMEROUS CASES OF ACFT EQUIP PROB FAILED B727-200 STATIC HEATERS.

Narrative: BTWN THE BEGINNING OF JUN/95 AND THE MIDDLE OF OCT/95 I HAVE ENCOUNTERED 18 DIFFERENT B727'S WITH BTWN 1 AND 3 (OUT OF A TOTAL OF 6) STATIC PORT HEATERS INOP. A VERY ROUGH EXTRAPOLATION FROM MY PERSONAL EXPERIENCE INDICATES POSSIBLY 20 PLUS PERCENT OF OUR OWN B727 INVENTORY BEING OPERATED WITH THIS PROB. ON A WORLD-WIDE BASIS THEREFORE, THE TOTAL NUMBER COULD BE AROUND 400-500 ACFT. FROM MY ENCOUNTERS, I'VE DETERMINED HOW TO TELL IN A MATTER OF SECONDS, FROM A GLANCE AT THE PITOT-STATIC AMMETERS, THE EXACT NUMBER OF HEATERS WHICH ARE INOP, AND ALSO, OF COURSE, WHICH SIDE OF THE FUSELAGE THEY ARE ON. THIS SIMPLE ANALYSIS, WHICH IS BASED ON THE CUMULATIVE AMPERAGE DRAW OF 3 PORT HEATERS PER AMMETER, IS NOT INCLUDED IN OUR PLT'S OPERATING MANUAL NOR, I'VE BEEN TOLD, IS IT MENTIONED IN BOEING'S OR OUR OWN MAINT PUBS. I HAVE ADDRESSED THIS PROB THROUGH PROPER COMPANY CHANNELS WITH 11 RPTS. FOR MONTHS NOW, THE OFFICIAL RESPONSE TO ME HAS BEEN, THANK YOU VERY MUCH, WE'VE SPOKEN WITH BOEING AND A FIX IS IN PROGRESS. YET ALMOST EVERY TIME I FLY A TRIP, I ENCOUNTER AT LEAST ONE ADDITIONAL B727 WITH THE SAME PROB. AND ALMOST EVERY TIME I WRITE ONE UP, I AM TOLD LOCALLY THAT NO REPLACEMENT HEATERS ARE IN STOCK. THEN, FOLLOWING FAA REGS, EITHER THE COMPANY DISPATCHER IS ABLE TO GIVE ME A 'NO ICING ENRTE' CLRNC, OR (I HAVE ASSUMED, UNTIL RECENTLY) THE PLANE IS GROUNDED UNTIL ONE CAN BE ISSUED. PUZZLED BY THE ONGOING PROB, I CONTACTED AN ACQUAINTANCE AT BOEING IN AUG/95. HIS CONFIDENTIAL RESPONSE WAS THAT THEY THEN HAD ONLY 9 REPLACEMENT HEATERS IN STOCK, PLUS 24 MORE 'ON THE WAY' FROM A SUBCONTRACTOR. 2 ACFT I'D WRITTEN UP AND ASSUMED WOULD BE FIXED, I LATER ENCOUNTERED WITH WHAT APPEAR TO BE THE SAME STATIC PORTS UNHEATED. ONE SHIP, WHICH HAD 3 STATIC PORTS UNHEATED, I FOUND ABOUT 2 MONTHS LATER TO STILL HAVE 3 UNHEATED. ANOTHER SHIP HAD ONE BAD PORT IN JUN/95, AND ALMOST EXACTLY 3 MONTHS LATER I FOUND IT WITH 2 BAD PORTS. IN BOTH CASES, ON THE FIRST GAR I NEGLECTED TO RECORD EXACTLY WHICH PORTS, BUT THE ODDS ARE GREATLY IN FAVOR OF THEM NEVER HAVING BEEN REPLACED. IF SO, I DON'T BELIEVE THE IGNORANCE IS DELIBERATE, A COMPANY REPRESENTATIVE RPTED TO ME THAT IN SOME INSTANCES, OUR MAINT HAS NOT BELIEVED MY WRITE-UP WAS CORRECT. THEY ALSO HAVE ALMOST NO CLR GUIDELINES IN THIS AREA. MANY TIMES I'VE HAD TO JOUST WITH MECHS, ALWAYS UNDERSTAFFED IN TODAY'S GRIM DEREGULATORY WAR-ZONE OF DISCOUNT AIRFARES, AND UNDER PRESSURE TO GET THE PLANES OUT, WHO INITIALLY DISBELIEVE ME. SOME HAVE QUESTIONED ME EVEN AFTER I TOOK THEM OUTSIDE AND HAD THEM HAND-FEEL THE PORTS. RESPONSES I'VE GOTTEN: 1) THE QUESTIONABLE PORT HEATERS ARE CONNECTED TO THE GND SHIFT MECHANISM, AND WILL HEAT UP AIRBORNE. 2) THEY ARE HEATED, JUST NOT AS WELL AS THE OTHERS. (I SIMPLY POINT OUT HOW AN ADJACENT HOT PORT, WHICH WILL SCORCH A FINGER IN A SECOND, CONDUCTS WARMTH THROUGH THE ACFT SKIN TO RAISE THE TEMP OF THE DEAD PORT A FEW DEGS ABOVE THE OUTSIDE AIR TEMP.) 3) IF THE AMBER PITOT-HEAT 'OFF' LIGHT IS OUT WITH THE PITOT-STATIC SWITCHES ON, THE STATIC PORTS ARE ALL ALSO HEATED. CLRLY, MANY HUNDREDS OF B727'S HAVE BEEN OPERATING WITH THESE THINGS UNHEATED, IN ALL KINDS OF WX, ALL OVER THE WORLD, FOR YRS. WHAT'S BEEN INTIMATED TO ME, IS STATIC PORT ICING IS NOT A PROB. OR IS IT? MY COMPANY'S PLANES, DESPITE A DRAMATIC CURTAILMENT IN MAINT STAFFING, ARE STILL PROBABLY AS SOUND AS ANY. YET, I'VE FOUND AS MANY AS HALF A SHIP'S STATIC PORTS UNHEATED (IN A FEW CASES, BOTH CAPT'S PORTS OR BOTH FO'S PORTS, THEREBY ELIMINATING THE REDUNDANCY FACTOR ON ONE SIDE OF THE COCKPIT). I WONDER, HAS BOEING DONE TESTS TO DETERMINE JUST HOW MUCH ICING IT TAKES (ON THE GND AS WELL AS IN THE AIR), TO PLUG THEM UP? USING ELEMENTARY KNOWLEDGE OF RELATIVE GASEOUS PRESSURE (AND STANDING, PROBABLY, ON VERY ROCKY SCIENTIFIC GND), I GATHER THAT COMPLETELY PLUGGED STATIC PORTS: 1) WOULD CAUSE ALTIMETERS TO HANG UP DURING DSCNT. 2) WOULD CAUSE AIRSPD INDICATORS TO DECREASE ARTIFICIALLY DURING CLB OUT, AS ATMOSPHERIC PRESSURE DECREASES. WHAT I AM ASKING OF YOU, IS TO PLUG THIS PROB INTO WHATEVER RECORDS YOU HAVE OF B727 CTLED FLT INTO TERRAIN IN POSSIBLE ICING CONDITIONS AND OF B727 UPSETS WHILE TAKING OFF IN POSSIBLE ICING CONDITIONS. CAN YOU FIND ANY CONNECTION BTWN THIS MALFUNCTION, AND PAST TRAGEDIES OR NEAR-DISASTERS? JUST HOW HIGH SHOULD THE LEVEL OF CONCERN BE? MY COMPANY SEEMS TO HAVE ADOPTED AN AMBIGUOUS APCH TO THIS, AS WELL AS A 'HANDS-OFF' ATTITUDE TOWARD ME. FOR THE LATTER I AM THANKFUL, BECAUSE I KNOW OTHER COMPANIES WOULD HAVE MADE MY JOB (IF I STILL HAD ONE) MISERABLE. NEVERTHELESS, THE LAST 4 MONTHS HAVE BEEN STRESSFUL FOR ME: I FEEL LIKE THE LONE RANGER, STRUGGLING TO OPERATE INSIDE A BULGING PERSONAL ENVELOPE OF SAFETY, PROFESSIONAL ETHICS, AND LOYALTY TO MY COMPANY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR HAS MOUNTED A CRUSADE WITHIN HIS ACR TO GET THE STATIC PORT HEATERS OPERATING. HE HAS CAUSED MANY FLTS TO BE CANCELED COSTING HIS ACR MANY DOLLARS IN LOST REVENUE. THE RPTR, AND THIS ANALYST, HAVE FOUND COCKPIT CREW PERSONS THAT MERELY WATCH FOR THE AMMETER TO JUMP AND DO NOT REALLY NOTE THAT THERE IS A MINIMUM OF 1.2 AMPS SHOWING. THE RPTR HAS HAD TO CONVINCE MECHS AND HIS ACR MGMNT THAT ALL 6 PORTS MUST BE HOT ON THE GND TO BE OPERATING PROPERLY. HE HAS WRITTEN AN ARTICLE, UNDER HIS BYLINE, FOR HIS PLT UNION SAFETY NEWSLETTER ABOUT THIS PROB. HE HAS HAD ONLY 1 NEGATIVE REACTION FROM HIS ACR MGMNT. IN GENERAL, HE IS SATISFIED WITH THE RESPONSE FROM HIS FELLOW PLTS AND HIS ACR. HE HAS FOUND 31 PORTS INOP ON 20 ACFT. THIS AMOUNTS TO 15 PERCENT OF HIS ACR'S B727-200 ACFT. THE PROC AT ANOTHER ACR, NOW OUT OF BUSINESS, WAS FOR THE SO TO TURN ON THE STATIC PORTS ON HIS PREFLT INSPECTION, THEN GO OUTSIDE AND FEEL EACH ONE OF THE 6 TO ASSURE THAT ALL WERE HOT TO THE TOUCH. THE RPTR BELIEVES THAT, BECAUSE THE ACFT ARE ALL ABOUT 20 YRS OLD, THESE HEATERS ARE FAILING WORLD WIDE AND THERE MAY BE SEVERAL ACFT FLYING AROUND WITH ALL REDUNDANCY LOST IN THE STATIC 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.