Expert Details

Expert in Fasteners, Latching mechanisms, structures, aircraft decompression.

Expert ID: 723244 California, USA

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Expert has extensive experience in the nonlinear analysis of structures and metals behavior. He has developed algorithms that enable accurate nonlinear finite element analysis of metallic components and assemblies up to the point of failure. As Chairman of the joint FAA/DoD/NASA Metallic Materials Property Development and Standardization (MMPDS) Finite Element Analysis Working Group (FEAWG) he is working with airplane companies to institutionalize these procedures. Expert has also advanced the state-of-the-art in decompression analysis for pressurized aircraft, taking into account the mass and inertia of venting panels to obtain a more accurate prediction of the loads on aircraft structures and interiors during a rapid decompression event.

Expert has conducted extensive research on the behavior of mechanically fastened joints, including development of finite element approaches that have been used to successfully predict joint load-deflection relationships. For his doctoral thesis, Expert performed over 1,000 analyses and corroborated the results with over one hundred experimental tests. Expert has studied the influence of all important installation and fastener parameters on joint behavior, including the influence of clamp load, hole size, fastener lubricity, panel properties and joint configuration. Expert has also performed thousands of static and dynamic tests on various mechanically-fastened joints in both metal and advanced composite specimens. He is also an expert in the testing and charactorization of metals, including tensile, fatigue, hardness and formability testing and analysis.

As Vice President of Engineering for the Hartwell Corporation, Expert oversaw the development of quick-release latching mechanisms for most of the new aircraft now being developed and commercialized, including engine nacelle latches for the A340-500/600, Boeing's new 787, the Airbus A-350, Europe's A400M and Bombardier's CRJ 700/900. He also co-invented and led the development of the post 9/11 terrorist-proof cockpit door pressure-sensing decompression latches now incorporated onto half the world's fleet of aircraft. While at Textron, Expert developed the Quick-Release cleat and inline skate axle products and other quick-release concepts for aerospace applications.

Expert has invented many of the aerospace fastening systems being used on today's aircraft, including the Composi-Lok (I & II), Visu-Lok II, Radial-Lok, robotically-installed Wedgelock clamps, Huck-clinch and CherryMax II. He has been awarded 31 United States patents for fasteners and latching mechanisms for the aerospace, industrial and sports equipment markets. Fastener materials with which Expert has expertise include aerospace structural alloys as well as continuous-fiber composites and plastics. Expert's expertise extends to all aspects of mechanical fasteners, including hot and cold heading, thread rolling, heat treatment, surface processing and machining. He has chaired several national and international committees dealing with fastener standards and testing, including the ISO committee dealing with solid rivets, blind fasteners and threaded pin/collar systems. As Chairman of IFI's Aerospace Technical Committee, Expert helped draft the FAA's TSO-C148 specification for aerospace fasteners and was the first to qualify fasteners under that document.


Expert is presently performing on-site consulting for Monogram Aerospace Fasteners, leading the development of fasteners he has invented. Immediate applications exist for the JSF for these products.He is also consulting for Steecon Enterprises, a manufacturer of pocket doors for business aircraft. Expert was engaged to develop decompression sensing mechanisms and perform decompression analyses for business jet aircraft.He has provided consulting services for Textron Inc. in relation to the fatal crash of a helicopter. Expert performed failure analysis and accident reconstruction duties, was an integral part of the inspections, and provided 24 hours of video taped deposition testimony.Expert provided litigation consulting in a lawsuit involving the crash of a private plane. The services were in regards to the engine cylinder head bolts.Expert also provided litigation consulting in a personal injury case involving a retractable bed in a motorhome.

Expert may consult nationally and internationally, and is also local to the following cities: Los Angeles, California - San Diego, California - Long Beach, California - Santa Ana, California - Anaheim, California - Riverside, California - Glendale, California - Huntington Beach, California - San Bernardino, California - Chula Vista, California

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Year Degree Subject Institution
Year: 2001 Degree: Ph.D. Subject: Structural Mechanics Institution: University of California- Irvine
Year: 1998 Degree: MSME Subject: Mechanical Engineering Institution: California State Univeristy- Fullerton
Year: 1996 Degree: BSME Subject: Mechanical Engineering Institution: California State University- Fullerton

Work History

Years Employer Title Department Responsibilities
Years: 2005 to Present Employer: Undisclosed Title: Principal Department: Responsibilities: Forensic Engineering, Fastener and Aerospace Industry Consulting
Years: 2000 to 2005 Employer: Hartwell Corporation Title: VP Engineering Department: Engineering Responsibilities: Managed the engineering function, including new product development, intellectual property and sustaining engineering.
Years: 1988 to 2000 Employer: Textron Aerospace Fasteners Title: VP Research and Development Department: Research and Development Responsibilities: Managed the R&D function, including products liability and intellectual property.
Years: 1979 to 1988 Employer: Monogram Aerospace Fasteners Title: Engineering Manager Department: Engineering Responsibilities: Manage the engineering department, including new product development and intellectual property.
Years: 1969 to 1979 Employer: Olympic Fastening Systems Title: Sr. Project Engineer Department: Engineering Responsibilities: New product development. Header and installation tool design.

Government Experience

Years Agency Role Description
Years: 2005 to Present Agency: DOD/FAA Role: Chair, MMPDS-FEAWG Description: Chair the Finite Element Analysis working group for the NASA/DOD/FAA MMPDS Committee.

International Experience

Years Country / Region Summary
Years: 1986 to 2006 Country / Region: Western Europe Summary: Expert made an average of 4 trips to Europe every year between 1986 and the present, staying up to three weeks per visit. These trips each concerned several countries (France, UK, Germany, Spain, Italy) and usually included visits with aircraft manufacturers. He also attended several standardization meetings as Chairman of one of ISO's fastener committees, and met with sports equipment manufacturers in Europe.
Years: 1986 to 2006 Country / Region: Asia, So. America Summary: Travel to Taiwan(1), South Korea(1), Peoples Republic of China(2), Japan(1), Singapore(1), Hong Kong(1), Brazil(1)---all to meet with aerospace or sports equipment customers.

Career Accomplishments

Associations / Societies
He is currently a member of ASME, CSPE, NSPE, ASCE, ASM, NAFE (correspondant) and is a SFES candidate.
Licenses / Certifications
Professional Engineering License (Calif., Mechanical Engineering)
Professional Appointments
He is currently Chairman of the NASA/DOD/FAA MMPDS Finite Element Analysis Working Group. He also has served as International Chairman of ISO/TC20/SC4/WG8 (fasteners), IFI's Aerospace Technical Committee, and other aerospace and technical committees.
Awards / Recognition
He is a member of Tau Beta Pi (an Engineering Honor Society)
Publications and Patents Summary
Awarded thirty-one (31) United States Patents and over 100 foreign patents for fasteners, latching mechanisms and sports equipment.

Additional Experience

Expert Witness Experience
Legal Experience

ON APRIL 15th 1997

In 1997 a Colgate-Palmolive corporate helicopter crashed immediately after takeoff into New York's East River, killing one occupant and severely injuring two others. The NTSB's probable cause was tail boom fatigue failure due to substitution of solid rivets with Cherry Max blind rivets during a recent repair procedure. At the time, FAA advisory circulars authorized replacement of certain solids with Cherry-Lock blind rivets, but not CherryMax. Since the failed tail boom separated from the fuselage at the repair site, the NTSB's conclusion was that the CherryMax rivets were weaker in fatigue strength than either solids or Cherry-Lock rivets, and therefore failed prematurely.

Subsequent inspections reveled that the fuselage failure actually started some distance from the repair site and was not influenced by the choice of Cherry Max over solids or Cherry Lock blind rivets. A cross section of a CherryMax in the failed structure showed the fastener to be free of defects.

A review of historical lap joint fatigue test results showed that in some combinations of panel thickness the CherryMax rivets had lower joint fatigue strength than Cherry-Lock rivets. That was not necessarily the case for the joint in the failed tail boom, which had a complex geometry difficult to replicate for testing purposes. Nevertheless, Cherry Max rivets were touted as suitable replacements for Cherry Lock by Cherry Textron marketing literature, without reference to the joint configuration.

My involvement included three days (24 hours total) of video-taped deposition while I was Vice President of Research and Development for Textron Aerospace Fasteners ("Cherry Textron"). Subsequent to my leaving to take another position at Hartwell Corporation, I served as an Expert Witness for Jones Hirsch Connors and Bull for another two years. Tasks included reviewing and analyzing all depositions and expert testimony and two on-site inspections of the wreckage. The case was settled before trial, with minimum impact to Textron.

Other Cases

• Calgary Canada 1988 Winter Olympics Skating Oval---Roof leakage allegedly caused by defective commercial blind fasteners. Settled during arbitration. I functioned as liaison with outside counsel, and in-house expert. Assisted with arbitration.

•Third-party lawsuit against Hartwell Corporation alleging that defective latching mechanism failed to maintain cargo door in secured position. During flight the cargo door is alleged to have opened with exiting cargo impacting the tail rotor, resulting in a crash and injuries. I functioned as liaison with outside counsel and in-house expert. This case is still pending.

•Federal Trade Commission (FTC) action against Textron (Docket # 9226) regarding acquisition of Avdel PLC. My involvement included a deposition plus five days of testimony in front of an FTC administrative law judge in relation to aerospace fasteners (engineering, joint strength, markets, etc).

•Patent and/or Trademark Infringement Olympic Fastening Systems v. Monogram Aerospace Fasteners (1979)

•Huck International v. Cherry Div. of Textron Inc. (1995)

•Cherry Div. of Textron Inc. v. Allfast Inc. (1998)

•Hartwell Corp. v. Avibank Div. of SPS Inc. (2003)

•Hartwell Corp. v. Harper Engineering (2005)

•Hartwell Corp. v. Adams-Rite (2005)
Training / Seminars
He completed the Engineering Management Program at California Institute of Technology as well as several follow-on courses related to new product development.

He also completed Textron’s two week "Executive Development Program" (Administered by the Harvard Business School)

Expert has also attended various seminars on lean manufacturing and intellectual property management.
Vendor Selection
Expert was responsible for evaluating and approving sources of supply for many projects throughout his career.
Marketing Experience
Expert conceived and developed the Textron Sports Technology business while at Textron Aerospace Fasteners. He functioned as General Manager and led the sales and marketing efforts as well. This business became sanctioned at the highest levels within Textron Inc. and was held up as an example of entrepreneurship to the other Divisions.

Fields of Expertise

bending moment, mechanical joining, metal deformation, metal forming analysis, structural mechanics, aircraft decompression, bolting live loading, metal testing, latch, quick-release fastener, latching, mechanical fastener, metal fastener, mechanically fastened joint, blind fastener, rapid decompression, airframe fatigue, National Transportation Safety Board, intellectual property management, hollow rivet, tee nut, Industrial Fasteners Institute, load (force), shear pin, compression failure, ferrous metal heat treatment, assembly structural testing, metal alloy heat treatment, steel stamping, fatigue failure, four-bar linkage, applied mechanics, airframe stress analysis, copper washer, metric fastener, industrial fastener, brass rivet, steel failure analysis, fastener coating material, plastic fastener, composite aircraft structure, fastener quality, fastener manufacturing, metal mechanics, threaded fastener manufacturing, mechanical reliability, Newtonian mechanics, cyclic loading to investigate fatigue, metal nondestructive testing, metal creep, nonlinear mechanics, machined parts manufacturing engineering, metal alloy, aluminum forming analysis, continuum mechanics, metal die stamping, metal artificial aging, fastener pin, sheet-metal screw, damage tolerance analysis, square-head bolt, mechanical fastener standard, mechanical fastener code, metal blanking, metal corrosion, mechanical reaction, hook and loop fastener, metal failure, aircraft component, metal heat treatment, fastening nut, mechanical system, mechanical coupling, wood screw, washer, threaded fastener, taper pin, structural bolt, staybolt, statistical mechanics, statics, square nut, fastening spline, metal spheroidizing, socket-head screw, slotted-head screw, set screw, screw, round-head bolt, rivet, retaining ring, metal quenching, metal physical property, metal normalizing, nail, metal stamping, metal screw, metal forming, metal drawing, metal coining, metal bending, metal mechanical property, fastening lock, lock washer, hot stamping, grommet, graphite epoxy composite, fluid mechanics, metal embrittlement, dynamics, deformation analysis, clip, clevis, clasp, clamp, fastening bolt

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