Tutorials will be held during main CMH-17 Coordination meetings based on interest level of the tutorials. See event registration page (when there are meetings) for meeting schedule and tutorial offerings. 

• Aircraft Certification with Composite or AM Parts Tutorial 
  • Offered based on interest 
  • Complimentary, registration required.
    NEW content Spring 2024 - now including additive manufacturing content 
• Statistics Tutorial 
  • Offered based on interest
  • Option for tutorial only
  • Option for software only
  • Option for software and tutorial (recommended)
  • See event registration for current rates
• Bonding M&P Tutorial
  • Offered based on interest
  • See event registration for current rates
• Ceramic Matrix Composites Overview Tutorial
  • NEW Spring 2024
  • Offered based on interest
  • See event registration for current rates

The Aircraft Structure Certification and Compliance Tutorial (updated in April 2024) provides an overview of certification requirements and unique means of compliance for composite and AM parts and structure for the topics covered in FAA AC 20-107B and EASA AMC 20-29. The tutorial complements and extends the information in CMH-17 Volume 3, Chapter 3 (completely re-written for CMH-17 Rev.H) by providing added content depth and including unique considerations for AM. The tutorial covers the following topics:

• Certification 101
• Technical Challenges
• Material and Process Control
• Structural Substantiation
• Maintenance
• Flutter
• Crashworthiness
• Flammability / Fire Protection
• Lightning Protection
• Simplified Means of Compliance
• Introducing New Materials and Processes

 

Printable Statistics Tutorial Outline

In support of Handbook objectives, the handbook includes methodology for performing a number of engineering processes associated with the design, manufacture and continued operational safety of composite materials.  These processes use rigorous statistical analysis requirements to confirm acceptability. These statistical procedures are sometimes intricate and confusing to individuals that are not familiar with them.

This tutorial is a comprehensive treatment of the CMH-17 methods for statistical analysis and their importance to proper development of design information. Students will participate in an interactive session on the CMH-17 statistical methods, including practical example problems.

Students will receive a copy of CMH17STATS. Students need to bring a laptop computer with Microsoft Excel to participate in the interactive sessions, as they will be focused on using the specialized software available: CMH17 STATS and HYTEQ.

Lecture: Statistics for Allowable Generation
Understanding A- and B-basis values and related statistical tests This section focuses on the concepts of A- and B-basis values, what they represent and why they are important. Students will leave with a clear statistical understanding of A- and B-basis values, and an in-depth appreciation of the significance of these values in engineering applications. In addition, a user-friendly flowchart that outlines the material property basis value generation process used by CMH17 Stats will be presented. The flowchart, which was jointly created by Statistics Working Group and Data Review Working Group, emphasizes engineering rationale while ensuring statistical validity.

Interactive Tutorial: Statistics for Allowable Generation (Includes Practical Example Problems) 
This interactive tutorial section will include practical example problems on how to compute engineering basis values as outlined in CMH-17. The CMH17 STATS program computes A- and B-basis values as well as other statistics. The use of engineering judgment in interpreting the software results in arriving at a final decision will be discussed.

Lecture: Equivalency Data Analysis
Understanding material equivalency and acceptance testing (material specification limits).  This section focuses on the concepts of equivalency testing, including the null hypothesis, Type I and Type II errors, the test statistics and the power of the test. Students will leave with a clear understanding of the purpose and criteria for material equivalency and acceptance testing. A modified co-efficient of variation approach for the purpose of generating interim basis values and specification limits will be explained and discussed.

Interactive Tutorial: Equivalency Data Analysis (Includes Practical Example Problems)
This interactive tutorial section will include practical example problems on how to compute equivalency test statistics outlined in CMH-17. HYTEQ (HYpothesis Testing of EQuivalence) computes the hypothesis test results for equivalency data. The use of engineering judgment to interpret the plethora of equivalency test results in arriving at a final decision will be discussed.

* Agenda and content is subject to change.

Structural Adhesive Bonding Materials and Processes Tutorial - Abstract

Structural adhesive bonding is an area of remarkable complexity contained in the bond’s seven thousandths of an inch-thick ribbon. This tutorial will attempt to clarify why structural adhesive bonding has a frequently unacceptable level of surprise, rarely good. These surprises can continue throughout a bond’s life cycle, not just during development and manufacturing.

Many failures of bonded structure are the result of misunderstanding (or miscommunicating) issues associated with bond processing, whether during original manufacture, field support, or repair. This tutorial covers bonding materials commonly used, and the processing they require to create successful bonded structure, starting with the simplest of bonds then proceeding incrementally up to the most challenging.

One of the central difficulties with structural adhesive bonding is that there appears to be at least one conspicuous (and perhaps even reasonable) exception to almost every rule or guideline considered. Rather than trying to provide absolute guidance in such an environment, the tutorial will attempt to provide counsel on how to proceed with the variety of answers, some contradicting each other, already found in the literature and in practice.

The tutorial is presented from the perspective of Materials & Process Engineering. While many areas of expertise must work together well to achieve bond system success, M&P has central responsibility for providing a good bond.

 

CMC Tutorial

Ceramic Matrix Composites Tutorial

Ceramic matrix composites (CMCs) have emerged as critical materials for the advancement of jet engines as well as other aero and energy related applications. The development of these materials for such applications has a history of over four decades. Though there are two main CMC systems, oxide and non-oxide, the non-oxide based composite systems will be emphasized here. This tutorial will focus on three primary areas:

1. The driving force for CMCs and the backdrop for CMC development in relation to preceding materials such as superalloys and carbon fiber reinforced composite systems.

2. What constitutes a CMC including CMC constituents, CMC mechanical behavior and toughening mechanisms, fiber architecture options and effects, and CMC processing approaches and their effects on properties will be described. Given this, there will be some discussion on the ability to optimize CMC properties.

3. CMC performance, in particular performance when subject to elevated temperature stressed-oxidation environments. An overview of CMC strength degradation due to the effects of thermo-chemical-mechanical environments will be described considering the makeup of different CMC systems. In addition, design considerations and mitigation strategies will be discussed which include the need for environmental barrier coatings (EBCs) for long time thermo-mechanical applications.