Narrative:

On aug/xa/01, I was assigned (single pilot) to fly a PA34-200T from pocatello, identification, to cheyenne, wy, (deadhead leg) and return with passenger under 14 crash fire rescue equipment 135. Cheyenne was IFR and forecast to stay that way. I rejected the first aircraft offered due to an inoperative autoplt (MEL item) and waited while another aircraft was ferried to pocatello and reconfigured for passenger operations. I filed an IFR flight plan to cheyenne using airways, although even the shortest low altitude routing is far from direct. This is my habit and what I teach as a company instructor. I then ask for 'GPS direct' once airborne. This way, if a direct routing is unavailable (due to radar outage, workload, etc) I am not left airborne trying to figure out where to go. I was cleared to cheyenne 'as filed,' and, instead of waiting until airborne to ask for direct, I asked the local controller to see if center would approve a VFR climb direct rock springs (avoiding the indirect airway segment) and told him that I could provide terrain separation. This kind of request is pretty standard. Pocatello WX was clear with unlimited visibility. After a short while, the local controller told me that I was cleared to 'climb VFR to 11000 ft, left turn on course approved, clear for takeoff.' I departed and turned left direct to rock springs. I was handed off to center and was told that I was radar contact 1 mi east of the pocatello airport. It's possible that I said that I was going 'direct rock springs' in my initial call, but I don't remember. A few mins later, center called and asked where I was going, and I replied 'direct rock springs.' the center controller, obviously angry, said that I had been cleared to malad (the first VOR on the flight plan route), and I replied that I had been cleared to rock springs. He said that 'on course' meant the route that I had filed. (The pilot-controller glossary does not address the meaning of 'on course' in this context.) he then asked me if I could provide terrain separation and when I said 'yes' I was cleared direct cheyenne. There was no mention of any traffic or terrain conflict. I called the tower on another radio and the local controller told me that he thought I was cleared direct to rock springs, not malad. I'm still not sure what went wrong here. Everyone involved used some non standard procedure or phrase (me included) and that certainly has to be a factor. Also, I was late and thus in a little bit of a hurry, so I may have misinterpreted the 'on course' to mean what I wanted, I probably needed to hear the phrase 'amended clearance,' but in our part of the world the traffic is light and almost all requests are 'approved as requested,' and when a request is denied we are always given a reason (eg, 'unable due to traffic'). Evidently center did not pass on the disapproval of the request, and hearing none, I sincerely believed that my request was approved, and that my clearance had been amended. Besides, there is no need to request a VFR climb to malad (terrain is not an issue on the airway!) I think that if I had made my request directly with the center rather than through an intermediary this whole thing might have been avoided. One possible lesson is that the absence of denial does not constitute approval.

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Original NASA ASRS Text

Title: A PA34 PLT MISINTERED HIS DEP CLRNC FROM PIH, TURNED DIRECT TO OCS INSTEAD THE FIRST FIX ON HIS FILED RTE.

Narrative: ON AUG/XA/01, I WAS ASSIGNED (SINGLE PLT) TO FLY A PA34-200T FROM POCATELLO, ID, TO CHEYENNE, WY, (DEADHEAD LEG) AND RETURN WITH PAX UNDER 14 CFR 135. CHEYENNE WAS IFR AND FORECAST TO STAY THAT WAY. I REJECTED THE FIRST ACFT OFFERED DUE TO AN INOP AUTOPLT (MEL ITEM) AND WAITED WHILE ANOTHER ACFT WAS FERRIED TO POCATELLO AND RECONFIGURED FOR PAX OPS. I FILED AN IFR FLT PLAN TO CHEYENNE USING AIRWAYS, ALTHOUGH EVEN THE SHORTEST LOW ALT ROUTING IS FAR FROM DIRECT. THIS IS MY HABIT AND WHAT I TEACH AS A COMPANY INSTRUCTOR. I THEN ASK FOR 'GPS DIRECT' ONCE AIRBORNE. THIS WAY, IF A DIRECT ROUTING IS UNAVAILABLE (DUE TO RADAR OUTAGE, WORKLOAD, ETC) I AM NOT LEFT AIRBORNE TRYING TO FIGURE OUT WHERE TO GO. I WAS CLRED TO CHEYENNE 'AS FILED,' AND, INSTEAD OF WAITING UNTIL AIRBORNE TO ASK FOR DIRECT, I ASKED THE LCL CTLR TO SEE IF CTR WOULD APPROVE A VFR CLB DIRECT ROCK SPRINGS (AVOIDING THE INDIRECT AIRWAY SEGMENT) AND TOLD HIM THAT I COULD PROVIDE TERRAIN SEPARATION. THIS KIND OF REQUEST IS PRETTY STANDARD. POCATELLO WX WAS CLR WITH UNLIMITED VISIBILITY. AFTER A SHORT WHILE, THE LCL CTLR TOLD ME THAT I WAS CLRED TO 'CLB VFR TO 11000 FT, L TURN ON COURSE APPROVED, CLR FOR TKOF.' I DEPARTED AND TURNED L DIRECT TO ROCK SPRINGS. I WAS HANDED OFF TO CTR AND WAS TOLD THAT I WAS RADAR CONTACT 1 MI E OF THE POCATELLO ARPT. IT'S POSSIBLE THAT I SAID THAT I WAS GOING 'DIRECT ROCK SPRINGS' IN MY INITIAL CALL, BUT I DON'T REMEMBER. A FEW MINS LATER, CTR CALLED AND ASKED WHERE I WAS GOING, AND I REPLIED 'DIRECT ROCK SPRINGS.' THE CTR CTLR, OBVIOUSLY ANGRY, SAID THAT I HAD BEEN CLRED TO MALAD (THE FIRST VOR ON THE FLT PLAN RTE), AND I REPLIED THAT I HAD BEEN CLRED TO ROCK SPRINGS. HE SAID THAT 'ON COURSE' MEANT THE RTE THAT I HAD FILED. (THE PLT-CTLR GLOSSARY DOES NOT ADDRESS THE MEANING OF 'ON COURSE' IN THIS CONTEXT.) HE THEN ASKED ME IF I COULD PROVIDE TERRAIN SEPARATION AND WHEN I SAID 'YES' I WAS CLRED DIRECT CHEYENNE. THERE WAS NO MENTION OF ANY TFC OR TERRAIN CONFLICT. I CALLED THE TWR ON ANOTHER RADIO AND THE LCL CTLR TOLD ME THAT HE THOUGHT I WAS CLRED DIRECT TO ROCK SPRINGS, NOT MALAD. I'M STILL NOT SURE WHAT WENT WRONG HERE. EVERYONE INVOLVED USED SOME NON STANDARD PROC OR PHRASE (ME INCLUDED) AND THAT CERTAINLY HAS TO BE A FACTOR. ALSO, I WAS LATE AND THUS IN A LITTLE BIT OF A HURRY, SO I MAY HAVE MISINTERPRETED THE 'ON COURSE' TO MEAN WHAT I WANTED, I PROBABLY NEEDED TO HEAR THE PHRASE 'AMENDED CLRNC,' BUT IN OUR PART OF THE WORLD THE TFC IS LIGHT AND ALMOST ALL REQUESTS ARE 'APPROVED AS REQUESTED,' AND WHEN A REQUEST IS DENIED WE ARE ALWAYS GIVEN A REASON (EG, 'UNABLE DUE TO TFC'). EVIDENTLY CTR DID NOT PASS ON THE DISAPPROVAL OF THE REQUEST, AND HEARING NONE, I SINCERELY BELIEVED THAT MY REQUEST WAS APPROVED, AND THAT MY CLRNC HAD BEEN AMENDED. BESIDES, THERE IS NO NEED TO REQUEST A VFR CLB TO MALAD (TERRAIN IS NOT AN ISSUE ON THE AIRWAY!) I THINK THAT IF I HAD MADE MY REQUEST DIRECTLY WITH THE CTR RATHER THAN THROUGH AN INTERMEDIARY THIS WHOLE THING MIGHT HAVE BEEN AVOIDED. ONE POSSIBLE LESSON IS THAT THE ABSENCE OF DENIAL DOES NOT CONSTITUTE APPROVAL.

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.