NTSB Factual Report

On April 6, 2018, about 1715 Pacific daylight time (PDT), a Mooney M20J airplane, N9133Z, was destroyed by impact and postcrash fire when it collided with terrain shortly after departure from the Petaluma Municipal Airport (O69), Petaluma, California. The airplane was registered to and operated by the pilot as an instrument flight rules (IFR) flight under the provisions of 14 Code of Federal Regulations Part 91 personal flight when the accident occurred. The private pilot sustained fatal injuries, instrument meteorological conditions (IMC) prevailed, and an IFR plan had been filed.

The flight departed from O69 destined for Fallbrook Community Airpark (L18), Fallbrook, California. When the flight failed to arrive on time, a concerned family member contacted Oakland Center (ZOA) and initiated a search for the missing airplane.

ZOA received an emergency locator transmitter (ELT) signal report at 1723 in the vicinity of O69. An alert notice (ALNOT) was issued by the Federal Aviation Administration at 1803, and an extensive search was launched. Aerial search operations were hindered by degraded weather conditions; however, a ground search was conducted by personnel from the Sonoma County Sheriff's Department, Petaluma Police Department, Petaluma Fire Department, Rancho Adobe Fire Department, as well as the Petaluma Airport Manager. About 2200 searchers located the accident airplane's wreckage about 2 miles northeast of O69.

At about 1700:30 the pilot received his IFR clearance from O69 to L18 with a void time of 1710.

A pilot rated witness familiar with operations at O69 was on the deck of the airport office monitoring common traffic advisory frequency when he heard the accident pilot radio "Petaluma ground, Mooney taxi to Runway 29" he then observed the airplane taxi to runway 11. He stated that the airplane remained in the runway 11 runup area for about 15 minutes. At about 1700 the pilot announced, "Petaluma traffic, Mooney departing Runway 29." At which time the witness transmitted "Runway 11" to which the pilot replied, "thank you, I appreciate the help." He observed the airplane depart off runway 11, climb to about 300 feet above ground level (AGL) before initiating a shallow left turn and disappearing into the fog. The witness reported that there were no unusual sounds from the airplane during the takeoff, and the engine sounded "strong, smooth and normal."

The National Transportation Safety Board (NTSB) investigator-in-charge (IIC) along with the rest of the investigative team reached the accident site on the morning of April 8. The airplane impacted in a near vertical attitude in in a soft, muddy mustard field with rolling hills at an elevation of about 307 ft mean sea level, on a heading of about 200°.

All the airplane's major components were located at the main wreckage site. The right wing was displaced from the fuselage and came to rest on the right side and forward of the fuselage. The left wing sustained extensive accordion style leading edge crushing near the tip lessening in severity toward the wing root. The engine and propeller separated from the airframe and were buried in about 3 feet of soft mud. The propeller remained attached to the crankshaft and the blades remained attached to the propeller hub assembly. Both blades exhibited leading edge polishing. The fuselage was largely consumed by postcrash fire. All the primary flight control surfaces remained attached to their respective attach points; however, flight control continuity could not be verified on-scene due to impact damage and postcrash fire.

The airplane was equipped with an Electronics International CGR-30P electronic engine monitor. The impact damaged device was recovered from the accident scene and retained for further examination.

The closest weather reporting facility was Petaluma Municipal Airport (O69), Petaluma, California. At 1655, an METAR from O69 was reporting, in part: wind calm, visibility, ¾ statute, mist; clouds and sky condition, overcast 600 feet; temperature, 59 °F; dew point 59° F; altimeter, 29.87 inches of mercury.