Narrative:

Aircraft was on the ramp to perform engine run checks. The aircraft was parked along the blast wall facing east. All three landing gear were chocked. One older black set of chocks was on the rh medium large transport; one new black set of chocks on the lh medium large transport; and an older yellow set of chocks on the nlg. Weather conditions were mostly clear; ramp dry; winds were 8-11 knots from 130 degrees.at the start of the run checks; there was 2000 lbs. Of fuel on each tank; 4000 lbs. Total fuel. The parking brake was set. We were following the engine run checklist and the maintenance manual. We completed idle speed checks; and were beginning accelerate/decelerate checks. We verified the lh engine would attain rated take off power. Lh engine throttle was reduced to idle; rh engine throttle was advanced to verify it would make rated take off power. As the rh engine was approaching 82% N1; the rh medium large transport forward chock dragged peeling the ribs from the chock. The nose tire dragged sideways between the nose wheel chocks. The aircraft started rotating to the left. The rh throttle was immediately reduced to idle and both brake pedals depressed to stop rotation. Engines were then shutdown; aircraft was repositioned and re-chocked (with three new chocks). Follow-up inspection revealed the lh brake pressure bleeding down with the parking brake engaged. Parking brake valve was ordered for replacement. Also; the nose wheel assembly and rh main wheel assembly are being replaced. I believe the brake pressure bleeding off and the type and condition of the chocks contributed to this.

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Original NASA ASRS Text

Title: Cessna Citation maintenance crew reported the aircraft began to rotate and move on the ramp during an engine run-up procedure.

Narrative: Aircraft was on the ramp to perform engine run checks. The aircraft was parked along the blast wall facing east. All three landing gear were chocked. One older black set of chocks was on the RH MLG; one new black set of chocks on the LH MLG; and an older yellow set of chocks on the NLG. Weather conditions were mostly clear; ramp dry; winds were 8-11 knots from 130 degrees.At the start of the run checks; there was 2000 lbs. of fuel on each tank; 4000 lbs. total fuel. The parking brake was set. We were following the Engine Run Checklist and the Maintenance Manual. We completed Idle Speed Checks; and were beginning Accelerate/Decelerate Checks. We verified the LH engine would attain rated take off power. LH engine throttle was reduced to idle; RH engine throttle was advanced to verify it would make rated take off power. As the RH engine was approaching 82% N1; the RH MLG forward chock dragged peeling the ribs from the chock. The nose tire dragged sideways between the nose wheel chocks. The aircraft started rotating to the left. The RH throttle was immediately reduced to idle and both brake pedals depressed to stop rotation. Engines were then shutdown; aircraft was repositioned and re-chocked (with three new chocks). Follow-up inspection revealed the LH brake pressure bleeding down with the parking brake engaged. Parking brake valve was ordered for replacement. Also; the nose wheel assembly and RH main wheel assembly are being replaced. I believe the brake pressure bleeding off and the type and condition of the chocks contributed to this.

Data retrieved from NASA's ASRS site 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.