Accident Overview
An aircraft operating under radar vectoring suddenly exhibited erratic steering and disappeared from radar. The pilot radioed that he "must have gone over some electronic interference that tumbled my gyros and screwed up my compass." However, the aircraft's instruments were vacuum-operated, powered by an engine-driven pump.
Impact and Damage
The aircraft impacted in a swampy area in a fast dive. The impact separated approximately six feet of the left wing from the rest of the airframe.
Investigation Findings
Disassembly of the engine-driven vacuum pump after the accident showed no evidence of failure prior to impact. This indicated that the pump was likely functioning at the time of the accident, contradicting the pilot's suggestion of electronic interference affecting the gyroscopic instruments.
Weather Conditions
The forecast for the area included ceilings of 2,000 to 3,000 feet broken with overcast conditions, occasionally below 1,000 feet, accompanied by rain showers and fog. The 1650 weather observation at Lakeland, Florida, reported rain showers to the north. Lakeland is located approximately 10 miles south of the crash site.