Our Experts and Staff

Brian Flinn, PE, PhD

Principal Materials Scientist and Engineer

Robert Scheibe, PE, PhD

Principal Mechanical Engineer

Robert Clark, PhD

Principal Materials Scientist

Dale Clark, MEng, PE

Mechanical Engineer and Materials Scientist

John Caroll, BS

Chemistry Laboratory Manager

Russell Jones, PhD

Senior Materials Scientist

Brian Flinn, PE, PhD


Principal Materials Scientist and Engineer

Brian Flinn, PE, PhD, is a Principal Materials Scientist and Engineer at GT Engineering. He joined GT Engineering to expand his forensic engineering and consulting practice involving material degradation and failures. This practice includes analysis of failure origins in metals, polymers/plastics/adhesives, composites, ceramics, glasses, concrete and wood products.  Since starting at GT Engineering, Dr. Flinn has been extensively involved in litigation matters involving personal injury, construction defects, corrosion and material degradation.  He has also taken lead responsibility in pipeline leaks, medical implant failure cases, and patent infringement matters.

In addition to his consulting practice, Dr Flinn has taught and conducted research at the University of Washington for over 20 years. Professor Flinn continues his research on the structure-property-processing relationships in a wide range of materials, including metals, ceramics, polymers and composites with a focus on the role of interfaces and industrial applications. Dr. Flinn earned his undergraduate and Masters degree from the Colorado School of Mines in Golden, Colorado  in Metallurgical Engineering and his Ph.D. in Materials Engineering from the University of California, Santa Barbara,  California.  He is a past director, past chairman, current member of and faculty director at the U of W for the Society for the Advancement of Materials and Process Engineering (SAMPE). Dr. Flinn is a founding member of the Federal Aviation Administration Center of Excellence for Advanced Materials for Transport Aircraft Structures (AMTAS) based at the University of Washington.

Specific research projects include adhesive bonding of composites, friction stir welding of titanium alloys, effect of shot peening process parameters on structure and fatigue properties, fracture and fatigue of  metallic nanolaminates, processing and properties of dental ceramics, mechanical properties of natural composites, and surface analysis techniques for quality assurance of bonded structures. Professor Flinn’s teaching includes courses on mechanical properties of materials, failure analysis of materials, molecular engineering of interfaces and surfaces, repair of composite materials, fundamentals of composite materials, and capstone senior design.

Robert Scheibe, PE, PhD


Principal Mechanical Engineer

Robert Scheibe is the Principal Mechanical Engineer at GT Engineering and is one of its founding members. For the past 33 years he has investigated and analyzed numerous accidents, failures, and fires across North America involving industrial machinery, vehicles, heavy equipment, appliances and consumer products. Dr. Scheibe specializes in the analysis of product safety, particularly from the standpoint of design, maintenance, and operation. He has acted as a consultant to numerous legal, insurance, industrial, and governmental clients and has testified as an expert witness on a variety of matters involving failure analysis, accident reconstruction, fire cause determination, and pedestrian footwear/walkway design and traction.

Dr. Scheibe holds bachelors and masters degrees in Mechanical Engineering from the University of Wisconsin and a Ph.D. in Mechanical Engineering from the University of Washington. He is also an Affiliate Associate Professor at the University of Washington in the Department of Mechanical Engineering where he teaches courses, performs research, advises students and publishes technical papers related to his research. Dr. Scheibe is a Registered Professional Mechanical Engineer in Washington and California and is recognized by the National Association of Fire Investigators as a Certified Fire and Explosion Investigator and Certified Vehicle Fire Investigator.

Robert Clark, PhD


Principal Materials Scientist

Robert Clark is a Principal Materials Scientist and founding member of GT Engineering. For over 40 years he has had a broad career in research, industry, and consulting. His specialty is the investigation and determination of cause for degradation and failure in materials. This has included extensive work involving metals, plastics and polymers, glasses and ceramics. He has led international research involving materials degradation in power plants. For the last 25 years he has had a nationwide consulting practice for insurance firms, manufacturers and industry, legal offices and government agencies dealing with failure analysis of materials. Dr. Clark has testified in cases across the United States as a Court qualified expert in materials science, mechanical engineering, metallurgy, corrosion and accident reconstruction.

Typical failure analysis projects have involved failures in engineered plastic or polymeric products such as molded parts, tubing, woven products and cordage (PVC, CPVC, PP, PE, PEX, ABS, EPDM, nylon etc.); failures in adhesives; failures in ferrous and non-ferrous metals, for example storage tanks, power grid structures, steam generators, piping systems, marine components, turbines, petrochemical plants; failure in glass and ceramics, e.g. corrosion of window lights, fracture origin in containers.

Dr. Clark holds a bachelors of science degree in Metallurgy, a masters of science degree in Materials Science and Engineering, and Ph.D. in Materials Science and Engineering with a Metallurgy specialization and a minor in Mechanical Engineering, all from the University of California at Berkeley. He previously managed the Corrosion Research and Engineering Section at Battelle Pacific Northwest Laboratories and served as a consultant to the U.S. Nuclear Regulatory Commission.

Dale Clark, MEng, PE


Mechanical Engineer and Materials Scientist

Dale Clark is a Mechanical Engineer and Materials Scientist at GT Engineering and has worked for more than 13 years as a consultant in the field of metallurgical and materials engineering. He holds a Bachelor of Science degree in Mechanical Engineering and master of engineering degree in Metallurgical and Materials Engineering, both from the Colorado School of Mines. Mr. Clark tailored his graduate studies to the field of forensic engineering with specific courses in failure analysis and plastics. He supplements his education and experience with continuing education courses on an ongoing basis. He is currently a licensed Professional Engineer in the state of Washington, Oregon and Nevada.

Mr. Clark has participated in a broad range of failure analysis projects, routinely serving as the principal investigator and project manager on investigations for industrial and manufacturing clients, the insurance industry, and legal teams. He has led investigations of failures of diverse materials and devices, including the failure of a fullering tool (used for making horseshoes) due to improper metallurgical heat treating; failure of a tube-cutting tool due to a fabrication induced stress riser; analysis of alternative welding procedures for a manufacturing client; analysis of mechanical and metallurgical failures for a petro-chemical plant; investigation of failures for oil and gas pipelines; numerous residential and industrial appliance failures; investigation of injuries related to trampoline gyms; and numerous investigations of failures in plastic piping and tubing and plastic structural components. Mr. Clark routinely conducts Scanning Electron Microscope (SEM) examinations, prepares and examines metallurgical and plastic cross-sections, and is familiar with interpretation of chemical laboratory testing including Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared (FTIR) spectroscopy.

John Caroll, BS


Chemistry Laboratory Manager

John Carroll manages the chemistry laboratory at GT Engineering and has more than 20 years’ experience in laboratory and field method development, research, and testing, using an extensive range of instrumentation. “His project experience includes expert technical support and both development and utilization of chemical and instrumental analysis techniques. Capabilities at GT Engineering’s chemistry laboratory include analysis of polymers, fibers and hydrocarbons by a variety of advanced techniques, such as differential scanning calorimetry, high performance liquid chromatography and infrared spectrometry as well as standard wet chemistry methodologies.

Previously, Mr. Carroll worked in industry as an Associate Scientist at HaloSource where he led investigations into biopolymer manufacturing and material defects and helped bring medical and chemical products to market often within FDA, EPA and state ecology regulatory environments.

For many years Mr. Carroll was a member of the Fiber and Polymer Group at the University of Washington where he conducted forensic polymer and plastics analyses and worked on projects dealing with human exposure to inorganic and organic contaminants including asbestos and formaldehyde for industry, insurance companies and law firms.

Mr. Carroll has one patent and three patents pending, 14 scientific publications, has presented scholarly works in the US, Canada, Italy, Kenya and Cuba, and has provided forensic testimony in court and depositions.

Russell Jones, PhD


Senior Materials Scientist

Russell Jones, PhD, is a Senior Materials Scientist with GT Engineering. He has 45 years of experience in materials development, evaluation, characterization and failure analysis. Dr. Jones has extensive experience in the fields of stress corrosion cracking, corrosion and high-temperature composites. His work in stress corrosion cracking includes evaluation of the effects of hydrogen, aqueous, high-temperature, and nuclear environments on crack growth behavior of iron, nickel, aluminum, and magnesium alloys, and ceramics and ceramic composites. Dr. Jones’ nuclear experience includes development of materials for advanced nuclear reactors and irradiation assisted stress corrosion cracking for light water reactors. Specific corrosion experience includes evaluation of the effects of interface, grain boundary, and surface chemistry on corrosion of materials including Yucca Mountain waste container materials. Dr. Jones has been instrumental in the development of SiCf/SiC composites for advanced nuclear reactor applications including high-temperature properties, corrosion and radiation stability. Dr. Jones has been a member of several expert panels providing guidance on corrosion and stress corrosion cracking.

Dr. Jones has performed R&D in support of several energy technologies and the automotive industry. He has worked on materials for advanced nuclear reactors, light water reactors, nuclear waste containment, gas pipeline, and steam turbines and gas turbine blading. Dr. Jones has worked on lightweight materials, hydrogen-materials compatibility issues and hydrogen storage for advanced automotive applications.

Dr Jones worked for the Westinghouse Research and Development Center from 1971 to 1973 doing materials development of steam and gas turbine materials; for Pacific Northwest National Laboratory from 1973 to 2005 doing research on a wide range of materials with an emphasis on corrosion and stress corrosion cracking; Exponent, Inc. from 2005 to 2006 as a Senior Managing Engineer in their Bellevue Office working in the Mechanics and Materials Practice; and for GT Engineering from May 2006 to the present.