Narrative:

Flying a cessna 172/0, I had to divert from my hayward objective. The aircraft experienced an engine roughness severe enough to shake the airplane. An oakland pilot also a flight instructor, experiences the same condition. I also diverted south from the linden radial 229 to also comply with VFR for cloud clearance along with the engine symptoms. Not expecting to put down in livermore, I did not have the CTAF dialed into the radio. Realizing the airport was there and I was crossing over from north to south, I entered left traffic pattern for runway 25R in accordance with class 'G' procedures. Since all of this happened quickly and intensely in a close traffic environment and poor cockpit lighting even with a flashlight handy, I was not able to look up the frequency and observe outside airport traffic conditions. I was already downwind turning base. When banking to turn base, I noticed an airplane that appeared to be below on straight approach to runway 25R. I instead proceeded across runway 25R across his approach path and, observing no other traffic in the air or on the ground. Proceeded to land on the north adjacent taxiway leaving runway 25R open for the approaching aircraft. The tower appeared not to be in operation. I do not believe I caused a traffic conflict or required a diversionary procedure by the other airplane. I paused at the base of the tower in case anyone wanted to question me, nothing happened. I proceeded to runway 25R, dialed in the CTAF. The other airplane that landed was not around. I announced runway 25R left crosswind departure and left. I could not get to hayward, so I returned to livermore, announced and entered left traffic runway 25R by class 'G' communication procedures and landed. As I taxied to transient parking, another airplane with other aircraft even though on the CTAF. About 3 months ago, an instructor landing at night at hayward, taxied this airplane into a ditch. Callback conversation with reporter revealed the following information: the reporter states that the problem with the engine was a broken engine mount. The entire aircraft would occasionally vibrate. The engine checked out fine on the ground at lvk, so the reporter pressed on to hwd only to find the WX below his, or the aircraft's capabilities. The aircraft was retrieved the next day. There have been no repercussions for any of the facets of this incident. The reporter thought that the engine problem was carburetor ice as low clouds were rolling over the hills from the west.

Related reports:

Google
 

Original NASA ASRS Text

Title: AN SMA PLT MADE A PRECAUTIONARY LNDG.

Narrative: FLYING A CESSNA 172/0, I HAD TO DIVERT FROM MY HAYWARD OBJECTIVE. THE ACFT EXPERIENCED AN ENG ROUGHNESS SEVERE ENOUGH TO SHAKE THE AIRPLANE. AN OAKLAND PLT ALSO A FLT INSTRUCTOR, EXPERIENCES THE SAME CONDITION. I ALSO DIVERTED S FROM THE LINDEN RADIAL 229 TO ALSO COMPLY WITH VFR FOR CLOUD CLRNC ALONG WITH THE ENG SYMPTOMS. NOT EXPECTING TO PUT DOWN IN LIVERMORE, I DID NOT HAVE THE CTAF DIALED INTO THE RADIO. REALIZING THE ARPT WAS THERE AND I WAS XING OVER FROM N TO S, I ENTERED L TFC PATTERN FOR RWY 25R IN ACCORDANCE WITH CLASS 'G' PROCS. SINCE ALL OF THIS HAPPENED QUICKLY AND INTENSELY IN A CLOSE TFC ENVIRONMENT AND POOR COCKPIT LIGHTING EVEN WITH A FLASHLIGHT HANDY, I WAS NOT ABLE TO LOOK UP THE FREQ AND OBSERVE OUTSIDE ARPT TFC CONDITIONS. I WAS ALREADY DOWNWIND TURNING BASE. WHEN BANKING TO TURN BASE, I NOTICED AN AIRPLANE THAT APPEARED TO BE BELOW ON STRAIGHT APCH TO RWY 25R. I INSTEAD PROCEEDED ACROSS RWY 25R ACROSS HIS APCH PATH AND, OBSERVING NO OTHER TFC IN THE AIR OR ON THE GND. PROCEEDED TO LAND ON THE N ADJACENT TXWY LEAVING RWY 25R OPEN FOR THE APCHING ACFT. THE TWR APPEARED NOT TO BE IN OP. I DO NOT BELIEVE I CAUSED A TFC CONFLICT OR REQUIRED A DIVERSIONARY PROC BY THE OTHER AIRPLANE. I PAUSED AT THE BASE OF THE TWR IN CASE ANYONE WANTED TO QUESTION ME, NOTHING HAPPENED. I PROCEEDED TO RWY 25R, DIALED IN THE CTAF. THE OTHER AIRPLANE THAT LANDED WAS NOT AROUND. I ANNOUNCED RWY 25R L XWIND DEP AND LEFT. I COULD NOT GET TO HAYWARD, SO I RETURNED TO LIVERMORE, ANNOUNCED AND ENTERED L TFC RWY 25R BY CLASS 'G' COM PROCS AND LANDED. AS I TAXIED TO TRANSIENT PARKING, ANOTHER AIRPLANE WITH OTHER ACFT EVEN THOUGH ON THE CTAF. ABOUT 3 MONTHS AGO, AN INSTRUCTOR LNDG AT NIGHT AT HAYWARD, TAXIED THIS AIRPLANE INTO A DITCH. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATES THAT THE PROB WITH THE ENG WAS A BROKEN ENG MOUNT. THE ENTIRE ACFT WOULD OCCASIONALLY VIBRATE. THE ENG CHKED OUT FINE ON THE GND AT LVK, SO THE RPTR PRESSED ON TO HWD ONLY TO FIND THE WX BELOW HIS, OR THE ACFT'S CAPABILITIES. THE ACFT WAS RETRIEVED THE NEXT DAY. THERE HAVE BEEN NO REPERCUSSIONS FOR ANY OF THE FACETS OF THIS INCIDENT. THE RPTR THOUGHT THAT THE ENG PROB WAS CARBURETOR ICE AS LOW CLOUDS WERE ROLLING OVER THE HILLS FROM THE W.

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.