Narrative:

The PF of helicopter XXX made a precautionary landing on the side of the freeway. Highway patrol called a tow truck to transport the aircraft to a recovery yard. I went to the recovery yard, talked to the pilot about his landing. I determined that he had made the landing due to fluctuating tachometer indication. I called the a&P that maintains the aircraft. He told me to check a plug on the l-hand magneto. This I did. I found no problem. I then started the engine and performed all of the power checks. All indications normal. I picked the aircraft up to a hover for power checks. All indications normal. I then stopped the aircraft and did another visual inspection, all normal. I restarted the aircraft and performed a takeoff and climbed to 700 ft AGL and flew 5-7 mins at various power settings, all normal. I then flew the aircraft to its base at lgb. During this flight, all indications normal. During all of the preflight and inspections, I did not find any discrepancies or make any alterations. I determined that the aircraft was airworthy and safe to fly. At the scene of the original landing, the FAA and NTSB were notified. It was not indicated that the aircraft could not be moved. I believe the original pilot had some electrical interference on the tachometer. He stated the power was stable. He made a good decision to make a precautionary landing. The repositioning flight was not an issue.

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Original NASA ASRS Text

Title: R22 PLT MADE A PRECAUTIONARY LNDG AFTER EXPERIENCING POSSIBLE ENG PROBS IN ZLA CLASS G.

Narrative: THE PF OF HELI XXX MADE A PRECAUTIONARY LNDG ON THE SIDE OF THE FREEWAY. HWY PATROL CALLED A TOW TRUCK TO TRANSPORT THE ACFT TO A RECOVERY YARD. I WENT TO THE RECOVERY YARD, TALKED TO THE PLT ABOUT HIS LNDG. I DETERMINED THAT HE HAD MADE THE LNDG DUE TO FLUCTUATING TACHOMETER INDICATION. I CALLED THE A&P THAT MAINTAINS THE ACFT. HE TOLD ME TO CHK A PLUG ON THE L-HAND MAGNETO. THIS I DID. I FOUND NO PROB. I THEN STARTED THE ENG AND PERFORMED ALL OF THE PWR CHKS. ALL INDICATIONS NORMAL. I PICKED THE ACFT UP TO A HOVER FOR PWR CHKS. ALL INDICATIONS NORMAL. I THEN STOPPED THE ACFT AND DID ANOTHER VISUAL INSPECTION, ALL NORMAL. I RESTARTED THE ACFT AND PERFORMED A TKOF AND CLBED TO 700 FT AGL AND FLEW 5-7 MINS AT VARIOUS PWR SETTINGS, ALL NORMAL. I THEN FLEW THE ACFT TO ITS BASE AT LGB. DURING THIS FLT, ALL INDICATIONS NORMAL. DURING ALL OF THE PREFLT AND INSPECTIONS, I DID NOT FIND ANY DISCREPANCIES OR MAKE ANY ALTERATIONS. I DETERMINED THAT THE ACFT WAS AIRWORTHY AND SAFE TO FLY. AT THE SCENE OF THE ORIGINAL LNDG, THE FAA AND NTSB WERE NOTIFIED. IT WAS NOT INDICATED THAT THE ACFT COULD NOT BE MOVED. I BELIEVE THE ORIGINAL PLT HAD SOME ELECTRICAL INTERFERENCE ON THE TACHOMETER. HE STATED THE PWR WAS STABLE. HE MADE A GOOD DECISION TO MAKE A PRECAUTIONARY LNDG. THE REPOSITIONING FLT WAS NOT AN ISSUE.

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.