Narrative:

On sep/xa/98, I was flying with a student in his own airplane, a navion. After training in brookhaven, ny (hwv), we went off the shoreline, south of isp class C airspace, for some air maneuvers. When we took off from hwv, I was aware that the main tanks were low (both tanks are 1 unit, they cannot be selected individually) but the airplane having an auxiliary rear tank, I was not concerned. We never allow this tank (22 gallons) to be less than 1/2 full. The rear tank cannot be used until the main ones have been used for about 1 hour since the excess fuel returns to the main tanks, cannot be used for takeoff and landing. Thus, I waited for my student to see it and manage the fuel. During the maneuvers he asked me about a cross country flight he had planned and along that line the question of fuel came up. He then pointed out at the low level of the main tanks and asked me if I would open the valve (located to the right) to start using the rear tank before we ran out of fuel on the mains. I commented that it would have been a good idea to do that a little bit earlier but it was ok. I pulled the t-handle and it came out, with the cable attached to it, obviously disconnected somewhere before the valve. I tried pushing and after a few mins, I realized that I would not get it to work and had to assume that the fuel was not flowing into the engine. The choice was going to bayport (23N) or to islip (isp), at about the same distance. The trip back to republic airport (frg), our base, as planned was too long under the circumstances. My choice of isp has to do with the level of services (class C) and the flat and bare surroundings of the airport as opposed to bayport. We received a clearance from new york approach into class C airspace and then were handled by the tower. We were cleared direct to the airport and had no need to request a priority. On downwind when we leveled off, a noise from the engine (real or imaginary) made me report a fuel problem (which we had to some extent) and we landed normally. On the rollout the engine stopped as soon as we cleared the runway. I then checked the valve (in the luggage compartment), it moved freely but I could feel that the cable was not connected. The airplane was towed to a repair shop where it showed that the cable had slipped out of its attachment to the valve (a simple screw with a hole in it to hold the cable, the same design is usually found on bicycle brakes). The repair was done within the hour and we went back to our training for a few more maneuvers (after adding some fuel), we tried the newly repaired valve on the ground and then in the air. We used it the next day on a long cross country trip to chicago without any problem. My comments: I should have done as when I am not teaching, switch to the rear before being very low (but my student might miss the importance if I just tell him), the design of the system could be better and more reliable.

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Original NASA ASRS Text

Title: N145 INSTRUCTOR AND TRAINEE WERE UNABLE TO USE FUEL FROM THEIR AUX TANK.

Narrative: ON SEP/XA/98, I WAS FLYING WITH A STUDENT IN HIS OWN AIRPLANE, A NAVION. AFTER TRAINING IN BROOKHAVEN, NY (HWV), WE WENT OFF THE SHORELINE, S OF ISP CLASS C AIRSPACE, FOR SOME AIR MANEUVERS. WHEN WE TOOK OFF FROM HWV, I WAS AWARE THAT THE MAIN TANKS WERE LOW (BOTH TANKS ARE 1 UNIT, THEY CANNOT BE SELECTED INDIVIDUALLY) BUT THE AIRPLANE HAVING AN AUX REAR TANK, I WAS NOT CONCERNED. WE NEVER ALLOW THIS TANK (22 GALLONS) TO BE LESS THAN 1/2 FULL. THE REAR TANK CANNOT BE USED UNTIL THE MAIN ONES HAVE BEEN USED FOR ABOUT 1 HR SINCE THE EXCESS FUEL RETURNS TO THE MAIN TANKS, CANNOT BE USED FOR TKOF AND LNDG. THUS, I WAITED FOR MY STUDENT TO SEE IT AND MANAGE THE FUEL. DURING THE MANEUVERS HE ASKED ME ABOUT A XCOUNTRY FLT HE HAD PLANNED AND ALONG THAT LINE THE QUESTION OF FUEL CAME UP. HE THEN POINTED OUT AT THE LOW LEVEL OF THE MAIN TANKS AND ASKED ME IF I WOULD OPEN THE VALVE (LOCATED TO THE R) TO START USING THE REAR TANK BEFORE WE RAN OUT OF FUEL ON THE MAINS. I COMMENTED THAT IT WOULD HAVE BEEN A GOOD IDEA TO DO THAT A LITTLE BIT EARLIER BUT IT WAS OK. I PULLED THE T-HANDLE AND IT CAME OUT, WITH THE CABLE ATTACHED TO IT, OBVIOUSLY DISCONNECTED SOMEWHERE BEFORE THE VALVE. I TRIED PUSHING AND AFTER A FEW MINS, I REALIZED THAT I WOULD NOT GET IT TO WORK AND HAD TO ASSUME THAT THE FUEL WAS NOT FLOWING INTO THE ENG. THE CHOICE WAS GOING TO BAYPORT (23N) OR TO ISLIP (ISP), AT ABOUT THE SAME DISTANCE. THE TRIP BACK TO REPUBLIC ARPT (FRG), OUR BASE, AS PLANNED WAS TOO LONG UNDER THE CIRCUMSTANCES. MY CHOICE OF ISP HAS TO DO WITH THE LEVEL OF SVCS (CLASS C) AND THE FLAT AND BARE SURROUNDINGS OF THE ARPT AS OPPOSED TO BAYPORT. WE RECEIVED A CLRNC FROM NEW YORK APCH INTO CLASS C AIRSPACE AND THEN WERE HANDLED BY THE TWR. WE WERE CLRED DIRECT TO THE ARPT AND HAD NO NEED TO REQUEST A PRIORITY. ON DOWNWIND WHEN WE LEVELED OFF, A NOISE FROM THE ENG (REAL OR IMAGINARY) MADE ME RPT A FUEL PROB (WHICH WE HAD TO SOME EXTENT) AND WE LANDED NORMALLY. ON THE ROLLOUT THE ENG STOPPED AS SOON AS WE CLRED THE RWY. I THEN CHKED THE VALVE (IN THE LUGGAGE COMPARTMENT), IT MOVED FREELY BUT I COULD FEEL THAT THE CABLE WAS NOT CONNECTED. THE AIRPLANE WAS TOWED TO A REPAIR SHOP WHERE IT SHOWED THAT THE CABLE HAD SLIPPED OUT OF ITS ATTACHMENT TO THE VALVE (A SIMPLE SCREW WITH A HOLE IN IT TO HOLD THE CABLE, THE SAME DESIGN IS USUALLY FOUND ON BICYCLE BRAKES). THE REPAIR WAS DONE WITHIN THE HR AND WE WENT BACK TO OUR TRAINING FOR A FEW MORE MANEUVERS (AFTER ADDING SOME FUEL), WE TRIED THE NEWLY REPAIRED VALVE ON THE GND AND THEN IN THE AIR. WE USED IT THE NEXT DAY ON A LONG XCOUNTRY TRIP TO CHICAGO WITHOUT ANY PROB. MY COMMENTS: I SHOULD HAVE DONE AS WHEN I AM NOT TEACHING, SWITCH TO THE REAR BEFORE BEING VERY LOW (BUT MY STUDENT MIGHT MISS THE IMPORTANCE IF I JUST TELL HIM), THE DESIGN OF THE SYS COULD BE BETTER AND MORE RELIABLE.

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.