Narrative:

I departed from ZZZ1 on an IFR flight plan to ZZZ2. The WX was clear and unrestr for the entire flight. 1 hour 45 mins later, the aircraft developed a vibration. I notified ZZZ center of vibration and asked for and received a diversion to closest airport. I reviewed all gauges, instruments, etc, to determine problem. A few moments later the engine made a loud bang and vibration got much worse. The engine cylinder then departed aircraft through cowl (cylinder broke side hinge and cowl opened) and hit left wing. I declared an emergency with ZZZ center and notified them I had a complete power loss. I maintained best glide speed and selected a landing spot that had a long stretch of highway with fields on each side. I turned north into the wind, put aircraft into landing confign, and landed safely on highway.

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Original NASA ASRS Text

Title: A BE-5 SINGLE PLT EXPERIENCED AN ENG FAILURE IN ZKC'S AIRSPACE, WHILE FLYING IFR, WHICH CAUSED HIM TO MAKE AN OFF ARPT LNDG.

Narrative: I DEPARTED FROM ZZZ1 ON AN IFR FLT PLAN TO ZZZ2. THE WX WAS CLR AND UNRESTR FOR THE ENTIRE FLT. 1 HR 45 MINS LATER, THE ACFT DEVELOPED A VIBRATION. I NOTIFIED ZZZ CTR OF VIBRATION AND ASKED FOR AND RECEIVED A DIVERSION TO CLOSEST ARPT. I REVIEWED ALL GAUGES, INSTS, ETC, TO DETERMINE PROB. A FEW MOMENTS LATER THE ENG MADE A LOUD BANG AND VIBRATION GOT MUCH WORSE. THE ENG CYLINDER THEN DEPARTED ACFT THROUGH COWL (CYLINDER BROKE SIDE HINGE AND COWL OPENED) AND HIT L WING. I DECLARED AN EMER WITH ZZZ CTR AND NOTIFIED THEM I HAD A COMPLETE PWR LOSS. I MAINTAINED BEST GLIDE SPD AND SELECTED A LNDG SPOT THAT HAD A LONG STRETCH OF HWY WITH FIELDS ON EACH SIDE. I TURNED N INTO THE WIND, PUT ACFT INTO LNDG CONFIGN, AND LANDED SAFELY ON HWY.

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.