Narrative:

10-15 mi south of ZZZ; center inquired if we were still on taxiway jx. We looked at the autoplt and it was in LNAV and altitude with ZZZ still as the next waypoint. Center turned us to a heading of 270 degrees. I asked if we should intercept jx on that heading. Center stated he would like us to go direct to abc; 'if we were able.' I read back affirmative; and we flew direct abc. The rest of the flight had no other problems. While trying to figure out how the autoplt could have missed the turn; we remembered that the copilot was flying and was also cleaning the screens and dusting the cockpit in cruise. We have a collins FMS 6000 installed. He had inadvertently bumped the automatic/inhibit button on the FMS; xxr; while he was dusting. This can be selected or bumped without any execute. All other data that is changed on this FMS has to be followed up with a deliberate button selection of the execute key. There is no warning; advisory; caution; or any other indication than the green 'automatic' turns to a green 'inhib' on the FMS. Since it was not known it was selected; there was no reason to look at that light. When wanting to tidy up the cockpit; I believe it to be imperative that each pilot is careful of what he or she is touching. This could be a hidden 'gotcha' for anyone; unless you always watch the automatic/inhib sequence after each waypoint.

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Original NASA ASRS Text

Title: CL60 EXPERIENCES TRACK DEV DUE TO HOUSEKEEPING ERROR.

Narrative: 10-15 MI S OF ZZZ; CTR INQUIRED IF WE WERE STILL ON TXWY JX. WE LOOKED AT THE AUTOPLT AND IT WAS IN LNAV AND ALT WITH ZZZ STILL AS THE NEXT WAYPOINT. CTR TURNED US TO A HDG OF 270 DEGS. I ASKED IF WE SHOULD INTERCEPT JX ON THAT HDG. CTR STATED HE WOULD LIKE US TO GO DIRECT TO ABC; 'IF WE WERE ABLE.' I READ BACK AFFIRMATIVE; AND WE FLEW DIRECT ABC. THE REST OF THE FLT HAD NO OTHER PROBS. WHILE TRYING TO FIGURE OUT HOW THE AUTOPLT COULD HAVE MISSED THE TURN; WE REMEMBERED THAT THE COPLT WAS FLYING AND WAS ALSO CLEANING THE SCREENS AND DUSTING THE COCKPIT IN CRUISE. WE HAVE A COLLINS FMS 6000 INSTALLED. HE HAD INADVERTENTLY BUMPED THE AUTO/INHIBIT BUTTON ON THE FMS; XXR; WHILE HE WAS DUSTING. THIS CAN BE SELECTED OR BUMPED WITHOUT ANY EXECUTE. ALL OTHER DATA THAT IS CHANGED ON THIS FMS HAS TO BE FOLLOWED UP WITH A DELIBERATE BUTTON SELECTION OF THE EXECUTE KEY. THERE IS NO WARNING; ADVISORY; CAUTION; OR ANY OTHER INDICATION THAN THE GREEN 'AUTO' TURNS TO A GREEN 'INHIB' ON THE FMS. SINCE IT WAS NOT KNOWN IT WAS SELECTED; THERE WAS NO REASON TO LOOK AT THAT LIGHT. WHEN WANTING TO TIDY UP THE COCKPIT; I BELIEVE IT TO BE IMPERATIVE THAT EACH PLT IS CAREFUL OF WHAT HE OR SHE IS TOUCHING. THIS COULD BE A HIDDEN 'GOTCHA' FOR ANYONE; UNLESS YOU ALWAYS WATCH THE AUTO/INHIB SEQUENCE AFTER EACH WAYPOINT.

Data retrieved from NASA's ASRS site as of May 2009 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.