CHI94DEE01

Witnesses reported the airplane impacted the west rim of a gravel pit during a visual approach. One witness reported hearing the engine lose power and several reported hearing no engine noise. Investigation revealed no evidence of preimpact airframe malfunction and the engine operated normally. The fuel system was highly modified from the configuration recommended by the kit manufacturer. The modification allowed uninterrupted fuel flow between all of the fuel tanks. A single fuel pick-up point was installed in one tank.

History of flight

On April 19, 1994, at 1515 central daylight time, an Experimental VK-30, N108P, impacted the terrain during a visual approach to Lake in the Hills Airport, Lake in the Hills, Illinois. The airplane was substantially damaged. The pilot and one passenger were fatally injured. Visual meteorological conditions prevailed. An IFR flight plan had been filed. The airplane was owned and operated by Remote Sensing Services, LTD., McHenry, Illinois. The flight originated in Lake in the Hills, Illinois, at approximately 1430.

Several witnesses to the accident reported they heard no engine noise. One witness reported the engine lost power during the visual approach.

Personnel information

The pilot, age 59, held Airline Transport Pilot certificate No. 1335633 issued on August 13, 1970, with airplane ratings for multiengine land aircraft and commercial pilot privileges for single engine land aircraft. The second class medical certificate was issued to the pilot on September 9, 1993, and contained the limitation that the pilot must wear corrective lenses while exercising the privileges of his airman's certificate. According to the records on file in the Aeromedical Certification Division at the Mike Monroney Aeronautical Center in Oklahoma City, Oklahoma, the airman had accrued 21,000 flight hours. 234 hours were in the Cirrus VK-30.

Aircraft information

The Federal Aviation Administration (FAA) aircraft registration certificate for N108P was issued to Remote Sensing Services, Inc., on September 29, 1992. The airplane builder listed on the Special Airworthiness Certificate was Steven C. Baldwin, who was also the passenger in the airplane at the time of the accident.

An hour meter was recovered from the right wheel well area. It indicated 234.2 hours. Representatives of the registered owner, Remote Sensing Services, and Cirrus Corporation indicated this was the actual total flight time of the airplane.

Wreckage and impact information

During approach to landing, the airplane impacted the west rim of an active gravel pit, coming to rest on a bearing approximately 100 degrees and 3,600 feet from the approach end of runway 27. Based on ground scars, the wreckage stopped within 50 feet of initial impact on a approximate magnetic heading of 300 degrees. The left wing leading edge was split open outward from the fuselage to the fuel filler opening at the wing tip. The right wing leading edge was split open outward from the fuselage to approximately one half its length. At this point, the wing was fractured chordwise. The remaining outboard section of wing was laying downward against the ground contour of the gravel pit. The nose of the airplane was fractured. The windshield and airplane entrance door separated from the airframe upon impact and came to rest adjacent to the right front side of the wreckage. The empennage was buckled on the right side, just aft of the engine compartment access door.

There was no evidence of any preimpact structural failure.

The instrument panel was bent forward along the lower row of instruments and had sheared the structure which fastened it to the control console. The throttle control cable was broken away from its mount. The throttle, propeller, and mixture controls were pushed to the full forward position.

No apparent damage could be seen to the rudder, elevators, or their respective stabilizers.

The three wood/composite propeller blades were broken at the hub. The wood splinters on the blades and hub were pointing in the opposite direction of the propeller rotation. The propeller was in the low pitch, high RPM position. The blades were recovered in an area approximately 30 feet aft of the airplane's tail and in line with the path of flight. The distance between the first and second ground slash scars was approximately 13 inches, between the second and third scars was approximately 31 inches.

The engine mount was bent downward from impact, with the right upper mount tube suffering a total fracture.

The landing gear position selector switch was in the down position and the landing gear was extended. The main landing gear were bent back. The nose landing gear was bent forward. The wing flap position selector and wing flaps were both in the 15 degree down position.

Control system continuity was established for all flight and engine controls.

Airplane engine and airframe logbooks contained identification numbers for the engine and airframe. Additionally, the airframe record contained an entry dated October 20, 1993, indicating the static, altimeter, and transponder tests were completed in accordance with the applicable regulations. This entry was endorsed by an appropriately rated certified repair station. An unsigned entry on the same date indicated an inspection of the engine fuel pump drive was performed in accordance with Continental Service Bulletin M93-9. Airworthiness Directive (AD) 93-16-15 was not applicable to the fuel pump, by serial number.

According to the date of issue of the Special Airworthiness Certificate on September 29, 1992, the next airplane conformity inspection required in accordance with the Operating Limitations issued on that date would be September 30, 1993. Without any additional sets of maintenance records, it cannot be established if the airplane met the requirements of the certificate issued by completion of the annual conformity inspection.

The engine is a six cylinder, opposed, Teledyne Continental, model TSIO-550-A, serial number 801005. All equipment and accessories installed on the engine were in accordance with the manufacturers recommendations.

The engine mount legs were fractured. Some of the mounting studs were bent or pulled from their threaded area; however, no fractures were visible on the crankcase. The oil sump was dented inward at the rear of the engine.

The engine fuel pump, part number 649368-17, serial number H299002B, was removed from the engine. The drive coupling, part number 631263, was found intact. By part number, AD 93-16-15, and Teledyne Continental Mandatory Service Bulletin M93-9 was not applicable.

A compression test of each cylinder was performed, with the following results:

#1-62/80, #2-68/80, #3-62/80, #4-52/80, #5-60/80, #6-60/80

After the engine test run and the engine had returned to ambient air temperature, cylinders #4 and 6 were retested with the following results:

#4-70/80, #6-69/80

The spark plugs were tested. All plugs fired evenly at the same test range.

The oil filter had been changed on the same day as this flight. The oil filter container was cut open. No metal particles or unacceptable levels of contamination were evident.

The engine was run in a test cell for an estimated total time of 25 minutes. The engine developed 2,800 RPM and 36 inches of manifold pressure. The fuel pressure was 16.5 PSI. At 2,000 RPM, the magneto drop was 20 RPM on each magneto, and the drop was smooth. The oil pressure was 45 PSI.

During the running of the engine, the airplane electric fuel pump, Dukes, part number EXPERIMENTAL, serial number -none-, was turned on, both in the high and low position, at various power settings. The fuel pressure did not raise in excess of .5 PSI, and engine performance did not change.

All monitored systems on the engine performed satisfactory during the test running.

The propeller clutch is a dry clutch, filled with stainless steel shot, which "locks" the drive ring to the hub. The propeller drive shaft is inserted into this clutch assemble. Disassembly of the clutch was performed. No slippage was evident.

The propeller drive shaft was intact from the clutch assembly mounted to the engine crankshaft flange, to the propeller hub. The rear drive shaft bearing and support showed no visible signs of previous damage or impending failure.

The fuel system was modified from the manufact