Narrative:

Problem: it is becoming very prevalent, at high altitudes, to receive descent clrncs with the following terminology: 'cleared to FL240 at pilot discretion.' in fact, it is unusual not receive some type of pilot discretion clearance. When a clearance is given to simply descend to a particular flight level, it becomes natural to ask if it is pilot discretion. Many times the controller will come back with 'pilot discretion to FL240 after FL310.' solution: the solution to this problem is to have controllers clarify that descent is to commence now on every high altitude descent clearance if required. This will leave no doubt in the pilot's mind and he will not have to ask. Sometimes the controllers get testy if you ask, 'is that at pilot discretion.' the above solution would smooth this area out.

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Original NASA ASRS Text

Title: USE OF PLT'S DISCRETION DESCENT CLRNCS.

Narrative: PROB: IT IS BECOMING VERY PREVALENT, AT HIGH ALTS, TO RECEIVE DSCNT CLRNCS WITH THE FOLLOWING TERMINOLOGY: 'CLRED TO FL240 AT PLT DISCRETION.' IN FACT, IT IS UNUSUAL NOT RECEIVE SOME TYPE OF PLT DISCRETION CLRNC. WHEN A CLRNC IS GIVEN TO SIMPLY DSND TO A PARTICULAR FLT LEVEL, IT BECOMES NATURAL TO ASK IF IT IS PLT DISCRETION. MANY TIMES THE CTLR WILL COME BACK WITH 'PLT DISCRETION TO FL240 AFTER FL310.' SOLUTION: THE SOLUTION TO THIS PROB IS TO HAVE CTLRS CLARIFY THAT DSCNT IS TO COMMENCE NOW ON EVERY HIGH ALT DSCNT CLRNC IF REQUIRED. THIS WILL LEAVE NO DOUBT IN THE PLT'S MIND AND HE WILL NOT HAVE TO ASK. SOMETIMES THE CTLRS GET TESTY IF YOU ASK, 'IS THAT AT PLT DISCRETION.' THE ABOVE SOLUTION WOULD SMOOTH THIS AREA OUT.

Data retrieved from NASA's ASRS site as of August 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.