All four magneto switches were in the ON position. The left fuel boost pump switch was in the ON position and the right fuel boost pump switch was in the OFF position. Both the left and right fuel tank selectors were positioned on their respective inboard fuel tanks. The crossfeed valve was found in the ON position. All fuel caps were in place in their filler necks. Approximately 1.5 oz. of a liquid consistent with avgas was found within the airplane fuel system. All four electric fuel pumps were operational when electrical power was applied to them. The flap jackscrew extension was consistent with the flaps being in the up position.
Both engines' crankshafts were rotated and each engine exhibited gear and valve train continuity. All cylinders produced thumb compression and suction. Both dual magnetos produced sparks at all leads. All removed spark plugs exhibited the appearance of normal combustion when compared to the Champion AV-27 spark plug chart. Both engines' turbocharger impellers spun when rotated by hand. The left and right propellers were found in the feathered position. No airframe or engine pre-impact anomalies were found.
Investigators looked into the pilot's performance and certification along with flight planning. An autopsy was performed on the pilot by the Lake County Coroner's Office. The study listed multiple traumatic injuries as the cause of death. The FAA Civil Aerospace Medical Institute prepared a Final Forensic Toxicology Accident Report on toxicological samples taken during the autopsy. The report, in part, stated that traces of marijuana were detected in his tissues. A pre-employment drug test on April 14, 2011, reported negative indications of drug use.
The pilot-passenger told Safety Board investigators “the pilot acted abnormally sporadic and weird in Florida,” but the investigator's report does not elaborate.
The pilot held a first-class medical certificate, dated Feb. 15, 2011, with limitations for hearing amplification and corrective lenses. The pilot previously reported to the FAA that he had a history of convictions for driving under the influence on both May 31, 2002, and Feb. 1, 1997.
The operator initiated a background check in accordance with the Pilot Records Improvement Act of 1996 (PRIA) on the pilot. This check showed his training records and check rides at previous employers and also revealed no legal enforcement actions resulting in a finding of a violation pertaining to the pilot. It listed a possible match and gave contact information for a Department of Transportation Compliance and Restoration Section in reference to checking the pilot's driver's record. The operator did not get that background check but was aware of the pilot's history of convictions.
The passenger-pilot said that the senior pilot had done all the flight planning for the trip. Investigators could not locate the original flight planning records but were able to re-create the navigation logs in consultation with FltPlan.com — the resource used by the pilot for his planning.
The accident flight plan showed a proposed departure time from JES of 1708, a proposed cruising altitude of 10,000 ft. MSL en route to PWK, 5 hr. of fuel on board, and it listed DuPage Airport as an alternate airport.
The flight plan logs showed that the 182 gal. of usable fuel available for the Piper Chieftain should have been sufficient for all flight legs that day. The final accident leg from JES to PWK would have required the most fuel. FltPlan.com calculations assumed a fuel burn rate between 34-37 gph for cruise and the operating manual indicated a fuel burn between 26-35 gph (depending on the power setting) with the engines leaned to best economy. The average actual fuel burn computed for the flight legs flown on Nov. 28, 2011, was 47 gph.
Fuel records recovered from the wreckage indicated that the airplane was filled to its capacity with fuel at CFJ, PXE and at JES. The fuel records also indicated that only 75 gal. of fuel were added at PBI. A nominal fuel burn rate of 30 gph would indicate that landing with a minimum of 22.5 gal. of fuel would meet the 45-min. IFR fuel reserve requirement: With the Chieftain's 182 gal. of usable fuel, the maximum amount of fuel that should be added after a flight conducted under instrument flight rules is 159.5 gal. N59773 was serviced with 167.3 gal. and 165.0 gal. at PXE and JES, respectively.