DURING A MULTI ENG TRAINING FLT; A PIPER PA34-200 L MAIN GEAR BROKE LOOSE DURING LNDG ROLL; RESULTING IN THE ACFT BEING TOWED TO PARKING. CORROSION WAS SUSPECTED OF CAUSING THE GEAR FAILURE.

Narrative

I DEPARTED DAB ARPT IN A PA34-200 WITH MR X. MR X AND I DEPARTED IN VISUAL CONDITIONS TO THE NW; WITH ATC FLT FOLLOWING AT 6500 FT. THE FLT WAS APPROX 1 1/2 HRS. UPON REACHING TLH ARPT WE REQUESTED A PRACTICE ILS APCH FOR RWY 27. OUR REQUEST WAS APPROVED. WE RECEIVED RADAR VECTORS TO THE FINAL APCH COURSE. UPON XING THE FAF; THE LNDG GEAR WAS EXTENDED. THE GEAR WAS CONFIRMED DOWN AND LOCKED WITH 3 GREEN INDICATIONS ON THE ACFT INST PANEL. AFTER RECEIVING CLRNC FROM TWR TO LAND; WE COMMENCED A NORMAL LNDG. AFTER TOUCHDOWN THE ACFT BEGAN TO SLOW DOWN. AS THE ACFT WAS ROLLING ON THE RWY; THE L WING DROPPED A LITTLE. MR X SAID THAT HE THOUGHT WE HAD A FLAT TIRE BECAUSE THE ACFT WAS PULLING A LITTLE L. WE LET THE ACFT ROLL TO THE NEXT RWY INTXN; AND TURNED R OFF THE RWY. WE GOT THE ACFT STOPPED AND REQUESTED AN ACFT TUG FROM GND CTL. GND CTL ADVISED US TO CONTACT THE LCL FBO. WE CALLED THE FBO AND THEY DROVE A TUG TO THE ACFT. MR X AND I SHUT DOWN THE ACFT AND GOT OUT TO FIND THAT THE L MAIN LNDG GEAR WAS IN AN ABNORMAL POS. THE LNDG GEAR HAD TRANSITIONED TO THE REAR FROM ITS NORMAL POS. THE LNDG GEAR J-LOCKS WERE IN THE LOCKED POS; AND THE INST PANEL HAD 3 GREEN (NORMAL) INDICATIONS. NO PERSONS OR PROPERTY WERE DAMAGED. WITH THE PICTURES I TOOK; I BELIEVE THE GEAR MOUNTS HAVE RUSTED THROUGH. I BELIEVE MAINT COULD DO A BETTER JOB ON INSPECTING THE ACFT.