ACFT DAMAGE CAUSED BY FAILURE OF ACFT LIFTING EQUIP.

Narrative

ACR ACFT; A FOKKER F-100; WAS BEING JACKED FOR THE PURPOSE OF PERFORMING ACR JOB CARD #MM IDENTED AS PCI800 (F-100 ACFT WEIGHING PROCS WITH CELL SCALES). THIS PCI WAS BEING ACCOMPLISHED BY 3 MECHS; 1 AT EACH JACK; A LEAD MECH MONITORING THE ACFT LEVELING INST AND 2 INSPECTORS ACCOMPLISHING THE ACTUAL WEIGHING OF THE ACFT. MY JOB WAS TO OPERATE THE NOSE JACK; THIS PCI REQUIRES MANUAL JACKING. THE NOSEWHEELS WERE OFF OF THE FLOOR AND THE ACFT WAS LEVEL. THE MAIN WHEELS WERE ABOUT TO COME OFF OF THE FLOOR WHEN THE L WING JACK CELL SCALE PIN SHEARED OFF AND THE JACK JUMPED OUTBOARD STOPPING AT THE FLAP FAIRING THEN PUNCTURING THE WING. THE ACFT LIFTED OFF OF THE NOSE JACK AND THEN THE R WING JACK CELL SCALE PIN SHEARED OFF AND THE JACK JUMPED OUTBOARD AND AFT OF THE WING AFT SPAR THEN PUNCTURING THE FLAP WELL PANEL; THEN THE ACFT NOSE CAME DOWN CAUSING THE FUSELAGE JACK PAD TO STRIKE THE JACK WEIGHING CELL ON TOP OF THE NOSE JACK AND KICKING THE JACK AWAY FROM THE ACFT. NO ONE WAS SERIOUSLY INJURED. THE ACFT SUSTAINED CONSIDERABLE WING DAMAGE. I BELIEVE THAT THE WEIGH CELL JACK ADAPTER HOLE IS REDUCED SO SMALL THAT IT PROVIDES A WEAK LINK BTWN THE JACK AND THE WEIGH CELL AND THAT THE PIN THAT GOES INTO THIS ADAPTER MAY HAVE BECOME WEAKENED OR CRACKED FROM PREVIOUS USE.