Accident Details
Probable Cause and Findings
The pilot of the other aircraft failure to maintain adequate clearance.
Aircraft Information
Registered Owner (Historical)
Analysis
HISTORY OF FLIGHT
On February 22, 1998, at 1045 central standard time (cst), a Wasielak Sonerai II L, N38NL, operated by a private pilot, was destroyed when during cruise formation flight, it collided with a Stanek Sonerai II LTS, N43804, also operated by a private pilot. The two airplanes subsequently departed controlled flight and impacted the terrain. Visual meteorological conditions prevailed at the time of the accident. The personal flights were being conducted under 14 CFR Part 91. Neither pilot filed a flight plan. Both pilots were fatally injured. The local flight originated near Burlington, Illinois, at 1015 cst.
The manager of Olson Airport, Burlington, Illinois, confirmed that both pilot's were keeping their airplanes in an open air hangar on the airport. A witness at the airport said that he observed both pilot's pull their airplanes out of the hangar at 0945 cst. The witness said that both pilots took off together at approximately 1015 cst.
A pilot, who was in the air in the vicinity of Palentine, Illinois, said that he monitored a conversation between two pilots trying to find each other in the air, on a frequency of 122.7 megahertz (MHZ), between 1000 and 1030 cst. He said that one of the pilot's said that he was "near the dome," and at an altitude of 2,500 feet [mean sea level]." The other pilot said that his "GPS" [global positioning satellite receiver] was not working. The first pilot repeated, "Look south, I'm 2 miles from the dome." The pilot said that one of the two pilots may have mentioned the city of DeKalb, Illinois. He said that they sounded like men 40 to 50 years of age. The pilot said that one of the two pilots directed a radio frequency change to 122.75 MHZ.
A witness on the ground observed the two airplanes approaching his farm from the northeast. He said that the two airplanes were heading in a southwesterly direction. The witness said that the two airplanes were just about overhead when the airplane on the right [north], the one slightly aft of the other airplane, drifted into the other airplane. The witness said that he heard a "pop," and then watched the airplanes come down. One airplane flew off to the southwest while the other airplane came straight down. The witness lost sight of both airplanes as they went behind a line of trees running along the south side of his farmhouse. The witness said he heard both airplanes strike the ground. He ran into the house and contacted the DeKalb County, Illinois, Sheriff's Department.
AIRCRAFT INFORMATION
SONERAI II L, N38NL
The airplane was a homebuilt kit. The airplane was issued a special airworthiness certificate, experimental, amateur-built airplane, on June 20, 1987. According to the aircraft logbook, the airplane made its first flight on October 11, 1986. The airplane was purchased by the pilot on October 2, 1988. The airplane was first flown by the pilot on the same day. The airplane's last recorded condition inspection was performed on November 9, 1994, by an airframe and powerplant mechanic. No record of condition inspections performed in 1995, 1996, or 1997 were found in the aircraft logbook. The aircraft logbook indicated that as of February 15, 1998, the airplane had logged 533.8 hours.
SONERAI II LTS, N43804
The airplane was a homebuilt kit constructed the by pilot-owner. The airplane was issued a special airworthiness certificate, experimental, amateur-built airplane, on October 16, 1992. According to the aircraft logbook, the airplane made its first flight on November 28, 1992. The airplane's last recorded condition inspection was performed on April 20, 1997, by an airframe and powerplant mechanic. The aircraft logbook indicated that as of January 31, 1998, the airplane had logged 337.5 hours.
PERSONNEL INFORMATION
The pilot of the Sonerai II L, N38NL, held a private pilot certificate with a single-engine land airplane rating, issued on November 11, 1980.
According to his logbook, he had 932.7 total flight hours in single-engine land airplanes. The pilot had logged 483.8 hours in the Sonerai II L. The pilot's last recorded biennial flight review was on October 15, 1995.
The pilot of the Sonerai II LTS, N43804, held a private pilot certificate with a single-engine land airplane rating, issued on April 16, 1983.
According to his logbook, he had 716.7 total flight hours in single engine-land airplanes. The pilot had logged 337.5 hours in the Sonerai II LTS. The pilot's last recorded biennial flight review was on January 10, 1998.
WRECKAGE AND IMPACT INFORMATION
The NTSB on scene investigation began on February 22, 1998, at 1250 cst.
SONERAI II L, N38NL
The Sonerai II L airplane's main wreckage was found resting inverted in a plowed field, approximately 2,660 feet south of Trombley Road, an east-west running gravel road, 1/2 mile north- northeast of the village of Malta, Illinois. The main wreckage consisted of the airplane's fuselage, empennage, wings, main landing gear, engine, and partial propeller.
The wreckage rested in a single crater, 46-inches long, 30-inches wide and 27-inches deep. The crater was oriented on a 270-degree magnetic heading. Impressions in the dirt, 8-feet long and 10- inches wide, just forward of where the airplane's left and right wings were located, spanned outward north and south of the crater. Numerous paint chips were found along the west edge of the impressions. Small pieces of paint, fiberglass, metal, personal effects, and smoked plexiglass were scattered westward from the crater for a distance of 54 feet within in a 165 degree arc. The engine, partial propeller, fuel tank, and forward instrument panel were located in the crater. The remainder of the airplane rested inverted on top of the crater. The airplane wreckage was oriented on a 270-degree magnetic heading.
The fuselage was bent downward and broken at the forward cockpit.
The cockpit floor was crushed upward and bent aft. The pilot's seat was bent aft and down. The metal frame, which made up the cockpit walls, was compressed downward and broken. The fabric covering the metal frame was buckled outward and shredded. The canopy frame was broken out at the hinges. The frame was broken into two pieces which were twisted and crushed. The plexiglass bubble windscreen was broken out and shattered. Several pieces of the canopy plexiglass showed parallel-running white paint rubs and scratches. The instrument panel was crushed aft and broken. All of the flight and engine instruments were destroyed. The fuel tank was crushed aft into the backside of the instrument panel. It had broken open along the left side and was compressed. The smell of fuel was prevalent at the site. Fuel was also found pooled at the bottom of the impact crater.
The fuselage frame, from a point aft of the cockpit, to just forward of the empennage, was bent downward. The fabric covering along the bottom right side of the aft fuselage was torn open. The covering along the left side of the aft fuselage was buckled outward and shredded. The elevator push-pull tubes were bent downward and broken at the empennage, and just aft of the cockpit. The aft fuselage frame, just forward of the empennage, was bent upward approximately 40 degrees. The fabric covering in this area was buckled outward and wrinkled. The vertical stabilizer, rudder, horizontal stabilizers, and elevator showed no damage. There was no damage to the airplane's tailwheel. Elevator and rudder control continuity was confirmed.
The airplane's left wing remained attached to the fuselage frame at the main spar and trailing edge mounting bolts. The wing was crushed aft along the entire span, to approximately mid-chord. The crush angle measured from the leading edge across the upper wing skin was approximately 73-degrees. From mid-chord aft to the aileron, the wing was buckled outward. The upper wing skin was broken open longitudinally at mid-span, along the rivet line.
The wingtip was broken off at mid-chord and along the rivet line. The forward half of the left wingtip was broken into numerous small pieces. The aft half of the left wingtip was broken longitudinally along the top rivet line aft to the aileron. The left aileron remained attached to the wing at the three hinges. The aileron was bent upward 20-degrees at mid- span. Left aileron control continuity was confirmed.
The airplane's right wing remained attached to the fuselage frame at the main spar and trailing edge mounting bolts. The wing was crushed along the entire span, approximately one-third aft. The crush angle measured from the leading edge across the upper wing skin was approximately 70-degrees. From the one-third aft point, aft to the aileron, the wing was buckled outward. The upper wing skin was broken open longitudinally at mid-span, along the rivet line. The right wing tip was broken off along the rivet line, and broken into numerous small pieces. The right aileron remained attached to the wing at the outboard hinge. The middle and inboard hinges were torn out of the aft wing spar. The right aileron was buckled in numerous places along its entire span. The right aileron was bent downward at the inboard corner of the trailing edge. Right aileron control continuity was confirmed
The airplane's main landing gear was bent aft under the fuselage. The landing gear legs sustained minor damage. The tires and wheelbrakes were undamaged. The firewall was crushed forward and bent around the rear of the engine. The back of the single magneto had punched a 4-inch wide hole through the firewall metal. The front of the airplane's lower cowling was crushed aft between the engine and the spinner. The remaining part of the lower cowling was broken out and shredded. The airplane's upper cowling was separated and broken into numerous pieces. The engine, propeller, and spinner were buried in the crater. Three of the four engine mounts were broken...
Data Source
Data provided by the National Transportation Safety Board (NTSB). For more information on this event, visit the NTSB Records Search website. NTSB# CHI98FA096