CEN09LA122

NTSB accident investigation · Beech A36TC · Three Rivers, MI · January 6, 2009

Accident · No injuriesLimited investigationFinal report
Date
January 6, 2009, 17:29 local (22:29 UTC)
Place
Three Rivers, MI
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N92WTBeech A36TC
Defining event
Enroute-descent: Structural icing
Weather
Visual (VMC) · Day
Status
Completed · report April 15, 2009
Report
Approved by Office Director
NTSB office
Central Region
Parties
FAA
Case key
73203

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The pilot's decision to continue the flight into an area with conditions that were conducive to icing and the loss of engine power due to induction icing.

Findings · 3

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Temp/humidity/pressure: conducive to structural icingEnvironmental issues › Conditions/weather/phenomena · Effect on equipmentBeech A36TC: 1 caseAll aircraft: 103 casesProbable cause
Power plant: air intakeAircraft › Aircraft power plant · Not specifiedBeech A36TC: 1 caseAll aircraft: 50 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot, who was on a cross-country flight, departed after a planned stop to refuel the airplane and receive a flight service station weather briefing. The pilot stated that he did not recall any reports of icing during the briefing. The pilot reported picking up light rime ice while descending from 9,000 feet for a global-positioning-system approach. The pilot reported that as he neared the airport he was able to maintain only 17 inches of manifold pressure. The pilot executed a forced landing on a frozen river about 1 mile south of the airport. The pilot reported the airplane normally stalls at 62 knots; however, it stalled at 82 knots during the landing. Inspection of the airplane revealed the entire span of both wings contained 1/16 to 1/8 inch of rime ice on the lower surface of the wings from the leading edge trailing aft about 12 inches. Ice was also visible on portions of the leading edge of both wings and the windscreen was iced over. The horizontal stabilizer was covered with about 3/16 inch of rime ice and the vertical stabilizer was covered with 1/8 to 3/16 inch of mixed ice. The alternate air door was in the closed position. The air inlet was crushed and packed with snow. All three propeller blades were twisted and bent rearward. The nose and left main gears collapsed and the right main gear was pushed up into the wing. The rear spars on both wings were bent and the flaps were buckled. The pilot received Direct User Access Terminal Service and flight service weather briefings that showed the existence and/or possibility of icing conditions near his destination.

Factual narrative

On January 6, 2009, at 1729 eastern standard time, a Beech A36TC, N92WT, experienced a hard forced landing on the frozen surface of a river about 1 mile south of the Three Rivers Municipal Airport (HAI), Three Rivers, Michigan. The commercial rated pilot and passenger on board were not injured. The airplane was substantially damaged. The personal flight was being operated under Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and an instrument flight rules (IFR) flight plan was filed. The last leg of the flight originated from the Branson National Airport (SGF), Springfield, Missouri, at 1402 central standard time. The trip originated in Brownsville, Texas, with a planned stop at SGF where the pilot refueled the airplane and received a flight service station (FSS) weather briefing. The pilot stated he did not recall any reports of icing during the briefing. The pilot stated he flew the en route portion of the flight from SGF to HAI at 9,000 feet above mean sea level (msl) and that the cloud tops were at 6,500 msl. He was in contact with South Bend approach control when nearing HAI. He stated the only pilot report regarding icing was from an airplane over Lake Michigan. The pilot was cleared for the GPS 27 approach. The pilot stated that the airplane picked up light rime ice during the descent through the clouds, breaking out of the clouds around 1,700 msl (900 above ground level). He stated he had the pitot heat and defrosters on, but he was unable to see out of the forward windscreen so he had to look out the side window during the landing. The pilot reported that as he neared the airport he attempted to add engine power, but was able to maintain only 17 inches of manifold pressure. He stated he maintained as much airspeed as possible until the airplane contacted the frozen river. The pilot reported the airplane normally stalls at 62 knots; however, it stalled at 82 knots during the landing. Post accident inspection of the airplane by inspectors from the Federal Aviation Administration South Bend, Indiana, Flight Standards District Office revealed the entire span of both wings contained 1/16 to 1/8 inch of rime ice on the lower surface of the wings from the leading edge trailing aft about 12 inches. Ice was also visible on portions of the leading edge of both wings; however, some of this ice was broken off due to the impact with the river. The windscreen was iced over. The horizontal stabilizer was covered with about 3/16 inch of rime ice and the vertical stabilizer was covered with 1/8 to 3/16 inch of mixed ice. The alternate air door was in the closed position and it appeared to be operable when inspected. The air inlet was crushed and impacted with snow during the landing. All three propeller blades were twisted and bent rearward. The nose and left main gears collapsed. The right main gear was pushed up into the wing. The rear spars on both wings were bent and the flaps were buckled. The pilot receiveda Direct User Access Terminal Service (DUAT) weather briefing at 0614 central standard time, prior to departing Brownsville, Texas. The forecast for northern Indiana included an outlook for IFR conditions due to ceilings and freezing drizzle and snow mist. This briefing included the terminal forecasts for both the South Bend Regional Airport (SBN), South Bend Indiana, located 36 miles southwest of the HAI and for the Battle Creek International Airport (AZO), Kalamazoo, Michigan, located 17 miles north of HAI. The SBN forecast for 2100 called for light freezing drizzle and snow. The 1300 and 2000 forecasts for AZO called for light snow. This briefing also included Airmen's Meteorological Information (AIRMETs) along the route for icing between Brownsville and SGF. The pilot contacted a FSS while at SGF to file a flight plan and obtain updated weather information. He stated to the briefer that there was a little rime ice coming into SGF. He asked what the ceiling and icing conditions were in the Kalamazoo area. The briefer told the pilot that if he had the AIRMETs for IFR, turbulence, and icing, he could give him an abbreviated briefing to which the pilot agreed. The briefer provided the current HAI conditions stating that it looked like a weak low pressure system was pushing into the area. Pilot reports were given for icing in the clouds near Jefferson, Missouri, and Springfield, Illinois, and light to moderate rime icing in the clouds at 6,000 feet near Goshen, Indiana. The pilot was informed that the heavier band of snow had moved through the Three Rivers area with isolated snow showers still in the area. The briefer also stated that the potential for icing still existed in the area.

Aircraft

Registration
N92WT
Reported as
Beech A36TC
Category
Airplane
Serial number
EA-230
Airframe hours
4,338.87
Engine
Cont Motor TSIO-520 SER, 300 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
J & F Wings Over Texas LLC
Registered owner
J & F Wings Over Texas LLC
Airworthiness certificate
Standard, Normal
Last inspection
Annual · September 20, 2008 · 31 hours before
Departed
SGF · Springfield, MO
Destination
HAI · Three Rivers, MI
Flight plan
IFR
Airport
HAI · Three Rivers Municipal

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
59
Injuries
None
Certificate
Private
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 3, With waivers/limitations
Last flight review
September 6, 2008
Seat
Left
Flight hours
1,333 total · 485 in this make and model · 22 in the last 90 days · 15 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
110° at 7 knots
Visibility
4 statute miles
Lowest ceiling
1,400 ft overcast
Temperature
28 °F, dew point 27 °F
Altimeter
29.57 inHg
Observed at
HAI, 5 nm away