CHI01FA093

NTSB accident investigation · Cessna 172H · Centralia, IL · February 21, 2001

Accident · FatalField investigationFinal report
Date
February 21, 2001, 07:05 local (13:05 UTC)
Place
Centralia, IL
Injuries
2 fatal
Damage
Destroyed
Phase of flight
Approach
Aircraft
N733SSCessna 172H
Weather
Visual (VMC) · Day
Status
Completed · report June 4, 2002
Report
Approved by Office Director
Parties
Cessna, Lycoming, FAA
FAA report
20010221003509A
Case key
51810

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 student pilot allowed the airspeed to get too low and inadvertently stalled the airplane, and the CFI delayed in taking remedial action.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Loss of control - in flightApproach
Airspeed - lowDual studentCause
Stall - inadvertentDual studentCause
Remedial action - delayedPilot in command(cfi)Cause
In flight collision with terrain/waterDescent - uncontrolled

Analysis

The airplane was destroyed when it impacted terrain 1.2 miles from the airport on a magnetic bearing of 003 degrees from the approach end of runway 18. The CFI weighed approximately 149 pounds and the student pilot weighed approximately 310 pounds. A witness reported seeing the airplane traveling toward him from west to east. He reported hearing the airplane's engine initially, and that the engine was at a low power setting. He reported the airplane was low, about 500 feet, and the airspeed was slow. The airplane was in a steep angle of bank and in a turn to the right. He reported the airplane was in "...a kind of a climb in a bank." After 270 degrees of turn, the airplane flipped over on its back and became inverted. The nose of the airplane then went down. He reported the nose of the airplane started coming up and the airplane looked like it was going to recover when he lost sight of the airplane behind a tree line. He reported hearing the airplane's engine revving to full power before hearing it impact the terrain. An examination of the airplane's system revealed no anomalies.

Factual narrative

History of flight

On February 21, 2001, at 0705 central standard time, a Cessna 172H, N733SS, operated by AIRGO, Inc., was destroyed when it impacted terrain 1.2 miles from the Centralia Municipal Airport (ENL), Centralia, Illinois, on a magnetic bearing of 003 degrees from the airport. The Certificated Flight Instructor (CFI) and student pilot were fatally injured. The 14 CFR Part 91 flight departed from ENL approximately 0620 on a local instructional flight. No flight plan was filed.

A witness reported seeing the airplane traveling toward him from west to east. The witness reported initially hearing the airplane's engine, and that the engine was at a low power setting. He reported the airplane was low, about 500 feet, and the airspeed was slow. He reported the airplane was in a steep angle of bank and in a turn to the right. He reported the airplane was in "…a kind of a climb in a bank." He reported that after 270 degrees of turn, the airplane flipped over on its back and became inverted. The nose of the airplane then went down. He reported the nose of the airplane started coming up and the airplane looked like it was going to recover when he lost sight of the airplane behind a tree line. He reported hearing the airplane's engine revving to full power. Then he heard the airplane impact the terrain approximately 1/4 mile away.

Personnel information

The 32 year old CFI was a commercial rated pilot with single and multi-engine airplane land and instrument pilot ratings. He held instructor ratings for single and multi-engine land airplanes and an airplane instrument instructor rating. He held a First Class Medical Certificate that was issued on July 1, 1999. The CFI was 5'7" tall and weighed approximately 149 pounds. He had a total of approximately 2,504 flight hours. He flew 112 hours in the last 90 days, which included 107 instructional flight hours.

The CFI had received his CFI rating on March 22, 1999, and had been flying as an instructor pilot for the operator. He had successfully completed a FAA chief flight instructor check ride for FAR Part 141 operations on December 8, 2000. The CFI was designated as the Chief Flight Instructor for the operator's FAR Part 141 flight school.

The CFI was a citizen of the United Kingdom. He did not have a visa waiver, a work permit card, or a "Green Card" issued by the United States Immigration and Naturalization Service (INS).

The 55 year old student pilot held a Third Class Medical Certificate that was issued on July 29, 1999. He had approximately 98 total flight hours. He flew 17.9 hours, which included 2.5 solo flight hours, between January 21, 2001, and the day of the accident. Prior to January 21, 2001, the student pilot's last documented flight was on August 18, 2000. He had logged a total of 18.0 solo flight hours. The student pilot was 6'4" tall and weighed approximately 310 pounds.

Aircraft information

The airplane was a single engine Cessna 172H, serial number 17268518, manufactured in 1977. The airplane seated four and had a maximum gross weight of 2,300 pounds. The engine was a 160 horsepower Lycoming O-320-H2AD engine. The last 100 hour inspection was conducted on December 14, 2000, and the last annual inspection was conducted on April 3, 2000. The airplane had flown 61 hours since the last inspection and had a total airframe time of 8,563 hours. The engine had 4,181 hours since a major overhaul on June 10, 1991. At the time of the overhaul, the engine had a total time of 1,371.1 hours. The engine cylinder compression readings recorded on December 14, 2000, during the last 100 hour inspection, were 1) 74/80, 2) 78/80, 3) 75/80 and 4) 75/80. The operator had purchased the airplane on October 15, 1994.

Meteorological information

The 0655 observed weather at Mt. Vernon, Illinois, located 16 miles southeast of ENL, was: Winds 020 at 7 knots, 10 miles visibility, clear, temperature 27 degrees F, dew point 13 degrees F, altimeter 30.50.

Wreckage and impact information

The wreckage site was located on the bank of Raccoon Lake, approximately 1.2 nautical miles from the threshold for Runway 18 at ENL and close to the runway centerline. The coordinates were 38 degrees 32.35 minutes N, and 089 degrees 04.42 minutes W. The wreckage path covered a distance of about 125 feet on a bearing of 130 degrees magnetic. The initial impact point was a tree root at the water's edge which had a piece of wing structure lodged in it. The main wreckage, located about 32 feet from the point of initial impact, came to rest against two hardwood trees about 10 feet above the lake's shoreline.

The empenage remained attached to the fuselage and both were found in a 50 - 60 degrees nose down attitude with the longitudinal axis aligned to the northeast. The right side of the cabin impacted the trees at or just aft of the front seats. The right cabin door was found against the left side of the fuselage. Neither of the front seat lap belts were intact. The webbing of both lap belts was torn and shredded. Both shoulder harnesses were attached to the airframe, but only the right shoulder harness was attached to a lap belt. The instrument panel was separated from the fuselage and was not intact. The engine was partially separated from its engine mounts and was found under the left wing, inverted, and pointing in a northerly heading.

The left wing remained attached to the fuselage and was located to the left of the fuselage. It exhibited aft compression of the leading edge and front spar along its span but remained intact. The wingtip had separated from the wing. Pieces of wing structure with electrical wiring in it were found crushed and embedded in a tree root at the initial point of impact.

The right wing impacted the hardwood trees. The wing separated at Wing Station (WS) 100.5. The inboard section of wing that remained attached to the fuselage exhibited crushing and buckling of its leading edge and spar. The section of wing from WS 100.5 to WS 208.0 exhibited crushing and buckling. A three-foot section of the right wing spar web was located on the ground to the left side of the fuselage.

All flight controls were found at the wreckage site. The flaps were retracted and the elevator trim was found 5 degrees up (nose down trim). Control cable continuity was established from the ailerons, elevator, and rudder to the respective cockpit controls. The aileron cables were found connected to the cockpit control yoke assembly. The aileron cables were found separated at approximately Fuselage Station (FS) 25 and the cables exhibited "broom straw" separations. The direct and crossover cables were connected at the left and right aileron bellcranks and exhibited continuity to FS 25 where the respective cables exhibited broom straw separations. The direct control cables had separated strands at the aileron direct cable pulleys in each wing. The National Transportation Safety Board (NTSB) retained the sections of cable with separated strands for further examination. The direct cable pulleys were found intact. There were no nicks, gouges, or scratches to the aluminum pulley bracket. Both pulleys rotated and they had no nicks, gouges, or scratches. Both pulleys had black grease residue on the side of the pulleys and in the pulley grooves. The cotter keys were intact. There were no signs of cable rub against any interior wing sections between the left and right wing aileron bellcranks and the wing roots.

The engine examination revealed the crankshaft rotated and there was valve train continuity and rear accessory gear rotation. Thumb compression and suction were observed on all cylinders. The carburetor was broken at the mounting flange. The single shaft, dual magneto was found separated from the engine. The cap assembly, ignition wiring, and left side of the distributor assembly sustained damage. The drive

Aircraft

Registration
N733SS
Reported as
Cessna 172H
Category
Airplane
Serial number
17268518
Airframe hours
8,563
Engine
Lycoming O-320-H2AD, 160 horsepower, reciprocating
Damage
Destroyed
Flight
Instructional · Part 91
Registered owner
AIRGO Inc.
Airworthiness certificate
Standard, Normal
Last inspection
Annual · December 14, 2000 · 61 hours before
Departed
ENL · Centralia, IL
Airport
ENL · Centralia Municipal Airport, runway 18, 5,001 × 150 ft, asphalt

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 · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
32
Injuries
Fatal
Certificates
Flight instructor, Commercial
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--no waivers/lim.
Last flight review
August 13, 2000
Seat
Right
Toxicology
Performed
Flight hours
2,504 total · 2,321 as pilot in command · 112 in the last 90 days · 20 in the last 30 days
Role
Student pilot
Age
55
Injuries
Fatal
Certificate
Student
Medical
Class 3, Valid Medical--w/ waivers/lim
Seat
Left
Toxicology
Performed
Flight hours
55 total

Weather

Conditions
Visual (VMC) · Day
Wind
20° at 7 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
27 °F, dew point 12 °F
Altimeter
30.50 inHg
Observed at
MVN, 16 nm away

Docket · 37

The files NTSB released with the investigation on May 14, 2002, on NTSB’s docket system: statements, records, photos and specialists’ reports. 13.9 MB in all.

Supplement AItem 1 · .PDF · 235 KBSupplement BItem 2 · .PDF · 328 KBMaterials Laboratory Factual ReportItem 3 · .PDF · 48 KBRecord of Interview & Director of Maintenance StatementItem 4 · .PDF · 92 KBMishap Site InformationItem 5 · .PDF · 65 KBAirport Diagram & Approach PlateItem 6 · .PDF · 100 KBNTSB Inspection of Aileron Cables & PulleysItem 7 · .PDF · 69 KBExcerpt From Cessna Service ManualItem 8 · .PDF · 15 KBLycoming Engine ReportItem 9 · .PDF · 291 KBPilot & Operator InformationItem 10 · .PDF · 388 KBCFI Pilot LogbookItem 11 · .PDF · 2.7 MBExcerpts From Maintenance LogbooksItem 12 · .PDF · 1.4 MBToxicological ReportItem 13 · .PDF · 191 KBStatement of Party Representatives to NTSB InvestigationItem 14 · .PDF · 649 KBRelease of Aircraft Wreckage, NTSB Form 6120.15Item 15 · .PDF · 83 KBPhoto 1. View of Wreckage Looking to the SoutheastItem 16 · .PDF · 470 KBPhoto 2. View of Wreckage Looking to the NorthwestItem 17 · .PDF · 444 KBPhoto 3. View of Left WingItem 18 · .PDF · 425 KBPhoto 4. View of Right Wing SectionsItem 19 · .PDF · 405 KBPhoto 5. View of Empennage and Underside of Horizontal StabilizerItem 20 · .PDF · 398 KBPhoto 6. Engine and Propeller Under Left WingItem 21 · .PDF · 421 KBPhoto 7. EmpennageItem 22 · .PDF · 343 KBPhoto 8. View of CockpitItem 23 · .PDF · 503 KBPhoto 9. View of Engine and Cabin With Left Wing Removed From WreckageItem 24 · .PDF · 445 KBPhoto 10. Left Aileron Cable at RollerItem 25 · .PDF · 300 KBPhoto 11. Right Aileron Cable Segment and Roller on Top and Left Aileron Segment on BottomItem 26 · .PDF · 276 KBPhoto 12. PropellerItem 27 · .PDF · 306 KBPhoto 13. View of Propeller BladeItem 28 · .PDF · 281 KBPhoto 14. View of Second Propeller BladeItem 29 · .PDF · 280 KBPhoto 15. View of Propeller BladeItem 30 · .PDF · 17 KBPhoto 16. Right Aileron Cable SegmentItem 31 · .PDF · 21 KBPhoto 17. Circumferential Rub Marks on Alternator HousingItem 32 · .PDF · 372 KBPhoto 18. Wing Piece That Was Found Imbedded in Tree RootItem 33 · .PDF · 406 KBPhoto 19. View of Left Aileron PulleyItem 34 · .PDF · 279 KBPhoto 20. View of Left Aileron PulleyItem 35 · .PDF · 253 KBPhoto 21. View of Right Aileron PulleyItem 36 · .PDF · 281 KBPhoto 22. View of Right Aileron PulleyItem 37 · .PDF · 289 KB

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.