NTSB Factual Report

HISTORY OF FLIGHT

On February 10, 2001, at 1450 central standard time, a Cessna 152, operated by Gran-Aire, Inc., was destroyed when it impacted the ground while maneuvering over Horicon Marsh located about 3 miles north of Horicon, Wisconsin. The 14 CFR Part 91 personal flight departed Timmerman Airport (MWC), Milwaukee, Wisconsin, approximately 1315 on a local flight. The airline transport pilot received fatal injuries. Visual meteorological conditions prevailed and no flight plan was filed.

A witness to the accident reported the following information:

"I was standing (facing north) on the river in front of Four Mile Island. All afternoon I was watching a metallic gray 2 person plane buzz around. It was always doing loops or other tricks. Right before the crash I saw the plane go almost straight up banking slightly to the left. It appeared to stall - holding its position for a second. Then it proceeded to fall nose first. It rotated about 1 1/2 times before crashing. It almost looked like it might pull out at the end. It wasn't a straight on crash. The left wing hitting first then the nose. I was approx. 3 miles or less away. I saw the snow fly up then a loud thud."

PERSONNEL INFORMATION

The pilot was an airline transport rated pilot with single and multi-engine land ratings. He held a First Class Medical Certificate and his last medical exam was conducted on August 31, 2000. The pilot had a total of approximately 1,800 flight hours, which included 1,400 hours multi-engine and 400 hours single engine. The majority of the single engine hours were flown in Cessna 172's. The last documented flight in a Cessna 172 was August 2000. The last documented flight in a Cessna 152 is unknown. The pilot's last spin training is unknown. The pilot had received spin training in a Cessna 152 in the fall of 1997 when he received his Certificated Flight Instructor (CFI) rating. For the previous 2 1/2 years, the pilot had been working as a corporate co-pilot in a King Air airplane. He completed Flight Safety Recurrent training every 6 months in a BE200 simulator, which included unusual attitude training. Over the previous 6 years, the pilot had been renting aircraft from the operator and usually rented Cessna 172's.

AIRCRAFT INFORMATION

The airplane was a single engine Cessna 152 manufactured in 1981. The airplane seated two and had a maximum gross weight of 1,670 pounds. The engine was a 115 horsepower Lycoming O-235-L2C engine. The last annual inspection was conducted on July 25, 2000. The airplane had flown 77 hours since the last inspection and had a total airframe time of 6,933 hours. The airplane had been owned by the operator since 1984, and was used as a training airplane.

METEOROLOGICAL CONDITIONS

At 1359, the observed weather conditions at Juneau, Wisconsin, located about six miles southwest of the accident site were: Winds 130 degrees at 8 knots, clear sky, 10 mile visibility, temperature -5 degrees C, dew point -9 degrees C, altimeter 30.51.

WRECKAGE AND IMPACT INFORMATION

The airplane impacted the ice-covered marsh at coordinates N 43 degrees, 30.37 minutes, W 088 degrees, 38.10 minutes, on a heading of 216 degrees magnetic. The wreckage path was limited to the point of impact and 10 feet forward of the wreckage. The left and right wing leading edges exhibited aft crushing along the length of their spans, with the crush angle being approximately 50 degrees. The left wingtip exhibited aft crushing and buckling. The right wingtip was intact except the leading edge of the fiberglass was broken. The tailcone and empennage were displaced and laying behind the left wing. There was no impact damage to the leading edges of the horizontal or vertical stabilizers. The cockpit section exhibited structural deformation and aft crushing. The instrument panel was not intact and numerous instruments were dislodged from their mounting brackets. The engine remained attached to the engine mounts and was completely buried in the ice and marsh. There was an undetermined amount of fuel in each of the metal fuel tanks, and both of the tanks' fuel lines were breached. Fuel was found in the fuel lines, gascolator, and carburetor. All flight control surfaces and control surface balance weights were accounted for at the accident site. Flight control continuity was established from the flight controls to the cockpit. The flaps were found extended in the 30 degree position and the elevator trim was neutral.

The propeller remained attached to the engine. One blade was bent aft and twisted. It had leading and trailing edge gouging and surface polishing. The other blade had a slight bend aft and leading edge polishing. The propeller spinner was deformed in a spiral shape.

The engine inspection revealed the engine rotated freely and continuity to the aft gears was confirmed. Thumb compression and suction were exhibited in all cylinders. Both left and right magnetos produced spark. The vacuum pump rotated and made suction on the inlet port. The carburetor was found separated from the inlet flange with the crushed air box attached.

No anomalies to the airframe or engine were found that could be associated with a pre-impact condition.

The aircraft was equipped with a seat belts and shoulder harnesses. Emergency responders reported that the seat belt was utilized by the pilot, but the shoulder harness was found unfastened.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy was performed on the pilot by the Milwaukee County Medical Examiner in Milwaukee, Wisconsin.

A Forensic Toxicology Fatal Accident Report was prepared by the Federal Aviation Administration (FAA) Civil Aeromedical Institute. The results were negative.

The National Transportation Safety Board's Medical Officer reported the pilot was diagnosed with multiple sclerosis (MS) in November 1999. Medical records maintained on the pilot by the FAA Civil Aeromedical Institute Aeromedical Certification Division revealed the following information:

1. A letter dated 5/29/00 to the Medical Review Branch from an FAA neurology consultant who reviewed the pilot's case noted that "he currently has no neurologic deficit which that would compromise aviation safety" and recommended that the pilot "be granted first class airman medical certification, subject to six-month reporting intervals."

2. A letter dated 8/14/00 to the Aeromedical Certification Division from the pilot's neurologist noted that the pilot had "multiple sclerosis of a very mild nature" and that he had "no residual symptoms" and "a normal neurological exam." It was also noted that he was "currently being treated with interferon beta 1-A."

3. On the pilot's latest application for 1st class Airman Medical Certificate dated 8/31/2000, the pilot noted that he was "diagnosed 11-14-99 with MS (remission)" and was receiving "interferon beta 1-A." He was given an authorization for special issuance of a 1st class certificate with the restriction "not valid for any class after February 28, 2001."

Additional medical information provided the following:

"Monthly MRI reports were obtained as part of a clinical trial of "Rebif/Avonex [interferon beta 1-A]" between March and September, 2000. All of the reports noted lesions consistent with the pilot's known diagnosis of multiple sclerosis and none of the reports indicated any new lesions or worsening of existing lesions."

ADDITIONAL INFORMATION

The Cessna 152 Pilot Operating Handbook (POH) states the following concerning spins:

"It is recommended that, where feasible, entries be accomplished at altitudes high enough to complete recoveries 4000 feet or more above ground level. At least 1000 feet of altitude loss should be allowed for 1 turn spin and recovery, while a 6 turn spin and recovery may require somewhat more than twice that amount for the Cessna Models 150, A150, 152, A152, 172, R172 and 177. For example, the recommended entry altitude for a 6 turn spin would be 6000 feet above ground level. In any case, entries should be planned so that recoveries are completed well above the minimum 1500 feet above ground level required by FAR 91.71."

The POH states the following limitation: "Intentional spins prohibited with flaps extended." The POH does not list flap extension as a procedure for recovery from an inadvertent spin.

A representative from Cessna Product Safety reported that during aircraft certification of the Cessna 152, it was demonstrated that the aircraft could recover from a spin with flaps extended. Approximately 700 feet of altitude was lost during the spin recovery.

The POH states that no acrobatic maneuvers are approved except for the following maneuvers: Chandelles, Lazy 8's, Steep Turns, Spins, and Stalls (except Whip Stalls).

The Federal Aviation Administration issued Aircraft Circular (AC) 91-48, "ACROBATICS-Precision Flying with a Purpose" on June 6, 1977. The AC 91-48 stated the following:

"a. FAR Section 91.71 defines "acrobatic flight" as "an intentional maneuver involving an abrupt change in an aircraft's attitude, an abnormal attitude, or abnormal acceleration, not necessary for normal flight." In addition, Section 91.15(c) indirectly refers to acrobatic flight in which it specifies that "unless each occupant of the aircraft is wearing an approved parachute, no pilot of a civil aircraft, carrying any person (other than a crewmember) may execute any intentional maneuver that exceeds:

(1) A bank of 60 degrees relative to the horizon; or

(2) A nose-up or nose-down attitude of 30 degrees relative to the horizon."

b. The above bank and pitch tolerances further define the differences between an acrobatic and non-acrobatic maneuver."

Parties to the investigation included the Federal Aviation Administration, Textron Lycoming, and the Cessna Aircraft Company.

The aircraft wreckage was released to Gran-Aire Inc.

NTSB Probable Cause

the inadvertent stall/spin. Additional factors included the aerobatic manuevers, low altitude, and the procedures not followed.