Narrative:

During run-in to the drop zone, we descended out of our cleared altitude of 3000 ft MSL to 2000 ft MSL without obtaining clearance from columbia approach control. I believe the problem arose from task saturation caused by thunderstorm dodging, and talking on 3 different radios. Another contributing factor was normal habit pattern. Scenario: we were on a local air drop training sortie to the drop zone. There were numerous thunderstorms in the area, and we had another C17A as our wingman. We normally fly at 3000 ft MSL to north field on an IFR clearance, and either obtain a cruise clearance into the drop zone, or cancel IFR so we can descend to 1000 ft AGL (or lower) to accomplish the drop. While coordinating a new drop time with the drop zone controller and altering our flight path and obtaining revised routing clearance, we neglected to coordinate for the cruise clearance. We were focusing on the radar to avoid the thunderstorms, and per our normal procedures, we started our descent to 2000 ft MSL. Approach called and told us we were supposed to be at 3000 ft MSL. We apologized, and canceled IFR since we were in VMC and only 10 mi from the drop zone. Approach acknowledged our cancellation, and the flight proceeded without further incident. Our overriding concern with thunderstorm avoidance, and the resulting changes in routing and drop times caused us to alter our normal habit of either canceling or obtaining a cruise clearance. Our solution to help prevent a further recurrence was to brief the airdrop crew members in the unit on the deviation and its causes.

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Original NASA ASRS Text

Title: MIL ALT EXCURSION NEAR CAE, SC.

Narrative: DURING RUN-IN TO THE DROP ZONE, WE DSNDED OUT OF OUR CLRED ALT OF 3000 FT MSL TO 2000 FT MSL WITHOUT OBTAINING CLRNC FROM COLUMBIA APCH CTL. I BELIEVE THE PROB AROSE FROM TASK SATURATION CAUSED BY TSTM DODGING, AND TALKING ON 3 DIFFERENT RADIOS. ANOTHER CONTRIBUTING FACTOR WAS NORMAL HABIT PATTERN. SCENARIO: WE WERE ON A LCL AIR DROP TRAINING SORTIE TO THE DROP ZONE. THERE WERE NUMEROUS TSTMS IN THE AREA, AND WE HAD ANOTHER C17A AS OUR WINGMAN. WE NORMALLY FLY AT 3000 FT MSL TO NORTH FIELD ON AN IFR CLRNC, AND EITHER OBTAIN A CRUISE CLRNC INTO THE DROP ZONE, OR CANCEL IFR SO WE CAN DSND TO 1000 FT AGL (OR LOWER) TO ACCOMPLISH THE DROP. WHILE COORDINATING A NEW DROP TIME WITH THE DROP ZONE CTLR AND ALTERING OUR FLT PATH AND OBTAINING REVISED ROUTING CLRNC, WE NEGLECTED TO COORDINATE FOR THE CRUISE CLRNC. WE WERE FOCUSING ON THE RADAR TO AVOID THE TSTMS, AND PER OUR NORMAL PROCS, WE STARTED OUR DSCNT TO 2000 FT MSL. APCH CALLED AND TOLD US WE WERE SUPPOSED TO BE AT 3000 FT MSL. WE APOLOGIZED, AND CANCELED IFR SINCE WE WERE IN VMC AND ONLY 10 MI FROM THE DROP ZONE. APCH ACKNOWLEDGED OUR CANCELLATION, AND THE FLT PROCEEDED WITHOUT FURTHER INCIDENT. OUR OVERRIDING CONCERN WITH TSTM AVOIDANCE, AND THE RESULTING CHANGES IN ROUTING AND DROP TIMES CAUSED US TO ALTER OUR NORMAL HABIT OF EITHER CANCELING OR OBTAINING A CRUISE CLRNC. OUR SOLUTION TO HELP PREVENT A FURTHER RECURRENCE WAS TO BRIEF THE AIRDROP CREW MEMBERS IN THE UNIT ON THE DEV AND ITS CAUSES.

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.