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Textron Aviation Safety Initiative January 21, 2017

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Textron Aviation is the company formed from

Cessna and Beechcraft in March 2014 – together

250,000+ airplanes have been delivered

Cessna 172 Skyhawk Beech Bonanza Cessna 208 Caravan

Cessna O-2 Skymaster

Beechcraft T-6A Texan II Cessna Latitude Hawker 4000

Beechcraft 1900D Cessna O-2 Skymaster

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Textron Aviation Piston Engine Airplanes

•  205,000+ produced since 1946

•  Of which 190,000 produced before 1987

•  Average age is 43 years old

•  Certified CAR 3

•  Made of Aluminum

•  Single Engine Airplanes flown 100-150 hours annually

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2015 Piston Engine Usage - Active US Aircraft Total of 141,141 Airplanes Representing All Manufacturers

Over sixty-five percent of active piston engine airplanes are Cessna or Beechcraft

Textron Aviation Piston Engine Airplanes

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•  Between 2000-2011 Cessna Aircraft developed new structural inspection programs to assure the continued safe operation of piston engine airplanes

•  For single engine airplanes, visual inspection techniques are utilized to detect –  Corrosion –  Cracks caused by metal fatigue

•  New structural inspection programs for Beechcraft airplanes are in work

Textron Aviation Safety Initiative

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•  Why Inspect?

– Corrosion (rust) and metal fatigue are inevitable

–  Corrosion and metal fatigue reduce the load carrying capability of the airframe –  Like people, airplanes age, and more frequent and intrusive inspections are

required to maintain health (safety)

Textron Aviation Safety Initiative

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•  Cessna SID Implementation in New Zealand –  Mandatory compliance

–  90 to 95% of inspected airplanes required maintenance action –  20% of those which required action needed major repair –  80% of the findings were corrosion and 20% cracking

–  Most common cracking area is around front and rear door posts –  Another common area of cracking is at lower strut fuselage attachments

Textron Aviation Safety Initiative

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•  The key to corrosion prevention is to keep the airframe free of moisture

•  A major contributing factor to corrosion is the environment –  Aircraft that operate in coastal environments are more susceptible to metal

corrosion – While water vapor already has a corrosive effect, the water vapor and salt

combination found in coastal environments creates a powerful corrosive agent

–  Aircraft that operate in areas that contain high amounts of industrial particles and fumes in the atmosphere also are more susceptible to corrosion

–  Aircraft that operate in areas where “environmentally friendly” runway deicers are used (i.e., potassium formate, potassium acetate, etc.) are more susceptible to corrosion

Corrosion Prevention

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Corrosion Severity Map

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•  There are several common options available to shield the aluminum from electrolytes including:

–  Cladding –  2024 sheet can be coated ("clad") with very thin layers (.001”) of pure

aluminum to protect from corrosion, known as 2024-T3 AlClad –  The sheet material is vulnerable when the cladding is compromised at

edges, drilled rivet holes, or if it is scratched –  Most airframe corrosion occurs at seams and joints, which is why cladding

alone is not sufficient –  Additional steps are necessary to protect seams, holes, and un-clad parts

from exposure to electrolytes

Corrosion Prevention

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•  There are several common options available to shield the aluminum from electrolytes including:

– Chemical Treatments – Alodine or other chemical treatments are used to enhance the corrosion

resistance of the pure aluminum cladding

Corrosion Prevention

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•  There are several common options available to shield the aluminum from electrolytes including:

–  Sealants –  Paint is the most commonly used sealant for corrosion protection and is the

best defense against airframe corrosion –  Modern polyurethane aircraft paints create a thick, impenetrable barrier

that effectively keeps moisture away from the metal, and lasts a long time - - 10 years or more

–  Paint only protects the exterior of the airframe –  Cessna airframe interiors of most pre-1986 airframes were not

painted (primed) –  Many Beech airframe interiors were only partially painted (primed)

Corrosion Prevention

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•  There are several common options available to shield the aluminum from electrolytes including:

–  Corrosion Preventative Compounds (CPCs) –  Effective means for protecting those parts of an airframe that were not

originally protected from corrosion –  Guidelines for application and use of CPCs are provided in the revised

Service Manual – CPCs must be reapplied periodically

–  The following CPCs are recommended for use on Textron Aviation airplanes

Dry film compounds: ARDROX AV-8* and AV-15 Cor-Ban 23* and Cor-Ban 35

Non-dry grease: Cor-Ban 27L

Non-dry oil: Corrosion X

* Preferred where high penetration of corrosion inhibiting compound is required.

Corrosion Prevention

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•  As airplanes continue to age, these numbers are likely to increase

•  Corrosion is responsible for approximately: –  7% of the airworthiness directives 1

–  20% of service difficulty reports (SDRs)

•  Corrosion can be deadly –  Corrosion contributed to 91 accidents/incidents in the United States between

1983 and 1994 2

– These and other accidents have resulted in hundreds of fatalities 3

1  Swift, S., “Rusty Diamond”, 24th ICAF Symposium, May 2007.

2  Hoeppner D,, Chandrasekaran V., Taylor A., “Review of Pitting Corrosion Fatigue Models”, 20th ICAF Symposium, 1999.

3  Aviation Safety Network Database, http://aviation-safety.net/index.php

Corrosion Results

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•  Corrosion and metal fatigue both reduce the load carrying capability of the airframe

•  Corrosion and fatigue are not entirely independent processes - corrosion affects the expected fatigue life of airframe parts

–  Corrosion pitting creates a stress concentration which leads to crack initiation and potentially faster crack

–  Corrosion reduces the thickness of a part and therefore increases the stress in the part

View of Spar Cap Fracture Surface View of Spar Cap Lower Surface

Corrosion and Metal Fatigue

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•  Beech 18 Wing Front Spar

•  Beech Bonanza/Baron Control Surfaces

•  Beech Bonanza/Baron Front Spar Leading Edge Lower Hinge-Pin Attachment

•  Cessna 177 Wing Spar

•  Cessna 200 Series Wing Spar

•  Cessna 182 Lower Strut Fitting

•  Cessna Single Engine Wing Spar

•  Cessna Single Engine Rudder Pedal

•  Cessna Single Engine Main Landing Gear

Corrosion Examples

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Beech Bonanza/Baron Control Surfaces

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Special Airworthiness Information Bulletin (SAIB) CE-15-22

Beech Bonanza/Baron Front Spar Leading Edge Lower Hinge-Pin Attachment

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177RG

177B Found as a result of SEB-57-03

Special Airworthiness Information Bulletin (SAIB) CE-16-16

Cessna 177 Wing Spar

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Found as a result of SID Inspection 57-11-01

Cessna 200 Series Wing Spar

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Found as a result of SID Inspection SID 57-40-01

Cessna 182 Lower Strut Fitting

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Wing Spar Corrosion

Found as a result of CPCP Inspection

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Cessna Single Engine Rudder Pedal

Fractured Pedal Arm Tube

SID 27-20-01

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Cessna Single Engine Main Landing Gear

•  Made from 6150M High- Strength Steel

•  A pit as small as .005” can initiate a fatigue crack which will result in fracture of the gear

•  Keep surface painted with polyurethane paint and blend out pits per Service Manual

Rust

Model 182 Flat Spring Gear SID 32-13-01

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.017” Pit

Cessna Single Engine Main Landing Gear

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– Over 700 people have died in fatigue related accidents since 1980

Metal Fatigue

•  Aviation has had to address metal fatigue in the design and inspection of airframes since 1954

•  Fatigue can be deadly – Metal fatigue contributed to 2240 deaths in 1885 airplane accidents between

1927 and 1980 1

– The five most common fatigue crack initiation sources in these accidents were: (1) bolt, stud or screw; (2) fastener or other hole, (3) fillet, radius or sharp notch; (4) welds and (5) corrosion

1  Campbell and Lahey 1984, ‘A Survey of Serious Aircraft Accidents Involving Fatigue Fracture’, International Journal of Fatigue, January 1984

2  ‘Investigation into Ansett Australia Maintenance Safety Deficiencies and the Control of Continuing Airworthiness of Class A Aircraft’, Appendix 8 from the Australian Transport Safety Bureau’s web site, www.atsb.gov.au.

2

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Fatigue Under Microscope Typical Fatigue Failure

What is Metal Fatigue?

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Aloha Airlines 1988

Dan Air 1977

F111 1969

Beech T-34 1999-2004

Cessna 172 Certified 1955

Cessna 206 Certified 1963

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Fuselage Fatigue Evaluation 1965

Wing Fatigue Evaluation 1969

Instructions for Continued

Airworthiness 1980

Empennage Fatigue

Evaluation 1989

AC91-82 Fatigue Management Program 2008

Comet 1954

1940 1950 1960 1970 1980 1990 2000 CAR FAA

Beech 23 Certified 1962

FAA Regulations Through the Years

Beech 35 Certified 1947

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Key Lessons Learned From High Profile Accidents

•  Comet – Fatigue must be considered in design, not just static strength

2,703 & 3,680 total hours

•  F111 - Manufacturing or accidental damage must be considered

105 total hours

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•  Boeing 707-321C - Fail-safe alone doesn’t work, need inspections

Key Lessons Learned From High Profile Accidents

47,621 total hours

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•  Boeing 737 - Inspection programs do not keep airplanes safe indefinitely. Eventually there needs to be a terminating action of modification or retirement.

Key Lessons Learned From High Profile Accidents

35,496 total hours

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•  Beech T-34 – Detailed inspection programs are needed for the entire airframe, not just for known areas of cracking

Key Lessons Learned From High Profile Accidents

3200, 8257 & 9316 total hours

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•  Model 402C designed in 1979 •  Twin-Engine unpressurized airplane •  Seats up to 9 passengers •  Often used for cargo hauling or scheduled airline passenger service

Case Study – Cessna 402C

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•  Wing spar cracking discovered in 1999 led to addition of wing spar strap (SID 57-10-16)

•  Engine beam cracking discovered in 2015 led to life limit of engine beams (SID 54-10-01)

•  Nacelle fitting (engine beam to wing attachment) cracking discovered in 2016 led to life limit of nacelle fittings

•  Carry-thru forward spar cracked in 2017 (SID 57-10-14)

Case Study – Cessna 402C

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•  Model 210 with cantilevered wing designed in 1967 •  Single-Engine unpressurized high performance airplane •  Seats up to 6 passengers •  Used for a variety of missions including cargo hauling, geophysical

survey, sight seeing as well as private usage

Case Study – Cessna 210

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•  Eight reports of wing spar cracking reported in 2012 (SID 57-11-03)

•  Horizontal stabilizer aft attachment fitting cracking discovered in 2011

•  Horizontal stabilizer forward spar cracking discovered in 2011 (SID 55-10-01)

Case Study – Cessna 210

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•  Beech Bonanza/Baron Rudder Brake Pedal Pivot Hole

•  Beech Bonanza/Baron Flight Control Cables

•  Cessna 180/185 Tailcone Stringer

•  Cessna 172 (Restart) FS 108 Bulkhead

•  Cessna 172/182/206/210 Forward Doorpost at Strut Attachment

•  Cessna 150/152 Vertical Stabilizer Attach

•  Cessna 177 Lower Wing Spar

Metal Fatigue Examples

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Fractured Rudder Brake Pedal Pivot Hole

Beech Bonanza/Baron Rudder Brake Pedal Pivot Hole

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Beech V35A Aileron Control Cable

CASA AD/GENERAL/87 - primary flight control cable assemblies using terminals constructed of SAE-AISI 303 Se or SAE-AISI 304 stainless steel must be replaced after 15 years

Beech Bonanza/Baron Flight Control Cables

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Special Airworthiness Information Bulletin (SAIB) CE-16-16 SID 53-10-01 AD under consideration

Cessna 180/185 Tailcone Stringer

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Found as a result of SID Inspection SID 53-12-03

Cessna 172 (Restart) FS 108 Bulkhead

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Crack AD or SAIB under FAA consideration SID 53-12-01

Cessna 172/182/206/207/210 Forward Doorpost at Strut Attachment

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Crack Special Airworthiness Information Bulletin (SAIB) CE-16-03 SID 55-11-02

Cessna 150/152 Vertical Stabilizer Attach

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Special Airworthiness Information Bulletin (SAIB) CE-16-16 SID 57-11-03

Cessna 177 Lower Wing Spar

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•  Inspections –  Based on field history –  Reviewed by customer focus group

•  Inspection Details –  Corrosion prevention and control program –  Directed visual inspection for corrosion –  ~15-20 visual inspections to look for cracks –  Boroscope and magnifying glass required to complete inspections

•  SID inspections are designed to be accomplished at an annual when airplane is opened up

•  Anticipated cost is dependent on flight hours and overall airplane condition –  Approximately 10 hours for low time airplane maintained per service manual –  Approximately 25 hours for high time airplane maintained per service manual –  Any required repairs are additional cost

SID Inspections

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•  Safety is a partnership between owners (maintainers), manufacturers and the FAA

•  Comply with airworthiness directives

•  Report anomalies

•  Send Pictures!!

Summary