July 2012 Issue
Tools for Homebuilders, Part 1
A conceptual approach to building looks beyond mere physical tools.
When you think of tools for homebuilders, you probably think of the physical tools: rivet guns, drills, squeezers, welders, drill presses, grinders and so on. But in the creation of an airplane, there are many other tools just as essential, such as learning tools, decision-making tools, organizational tools and motivational tools.
Homebuilt or amateur-built aircraft are defined as those in which the major portion has been fabricated and assembled by persons who undertook the construction project solely for their own education or recreation. In short, this means you are learning the technology and craft of airplane building and are having fun doing it.
So how do you learn? Your formal education was likely structured in much the same way from kindergarten through university. That is, a teacher stands at the front of the classroom and delivers the course material to the students. Each subject has a textbook, and homework is assigned using the textbook to go into more detail. If this method of learning has worked well for you, you probably haven't thought much about its effectiveness. But it doesn't work for everyone.
A forum setting allows learning aircraft-specific knowledge in a small group.
Learning Tools: Technology
You are probably already a pilot, and you've learned how to control and navigate an airplane. You also learned a few basics about different types of airplane construction, aerodynamics and engines. But building an airplane requires more detailed knowledge of airplane technology, such as structures, powerplants, materials, fasteners, electrical systems and fluid systems.
As an adult, you've probably figured out how you learn best, and if you haven't, think about it. Do visual presentations such as videos and slides capture your attention? Do you prefer listening to audio books? Are you the type of person who goes to the library or buys books to study something new? Or do you learn best through hands-on experience?
Usually a combination of methods, or a multimodal approach, is best. Understand what works for you and use it in your approach to building.
Mentors make it easier to learn the craft of aircraft building.
Next, consider the learning environment. Do you prefer a formal setting such as a traditional classroom, or do you learn best in the comfort of your own home? Are you a solitary person, or do you prefer learning in a group setting? If you are easily distracted by noise and interruptions, find a quiet environment.
Next, consider the learning community; few people can build an airplane alone. Friends, fellow pilots, specialist craftsmen and component suppliers can be enlisted to help. Through the Internet, the learning community has expanded to include the entire world, not just your hometown.
Embarking on a major project such as building an aircraft is a good incentive to learn new skills, but it can be overwhelming. Be assured that having a project will help you learn what you'll need to know, even if it's been years since you sat in a classroom. Adults tend to be problem-centered, results-oriented, self-directed, discriminating and relevance-driven, and they accept responsibility for their own learning. All of these traits work in your favor.
You'll find a number of sources to help you learn the technology of aircraft:
• Books: Textbooks and other reference books are readily available in libraries and from general and specialist booksellers. At the least, you will need the FAA publication AC 43.13 Acceptable Methods, Techniques, and Practices—Aircraft Inspection and Repair (available for download at http://www.faa.gov).
• Magazine articles: Enthusiast publications such as the one you're reading now are a good source of information. Many have previous articles archived on a related web site.
• Online courses: Many professional associations have online courses that can address your needs, such as the Society of Automotive Engineers and the American Institute of Aeronautics and Astronautics. (Many even publish technical and historical books.) Colleges and universities also offer online courses.
• Video courses: The Experimental Aircraft Association (EAA) has numerous short video courses on a variety of topics, including aircraft technology.
• Forums: Online or onsite forums offered by some kit manufacturers and suppliers may be a valuable resource. Many additional forums are presented at major annual fly-ins around the country.
• Trade schools: The academic requirements for an Aircraft and Powerplant mechanic's certificate are available as correspondence or online courses from numerous trade schools around the country. Embry-Riddle Aeronautical University and, in Canada, the International Correspondence School's Aircraft Mechanics course, are two such sources. While you don't need an A&P certificate to build an airplane, these courses will give you a thorough grounding in aircraft technology. The FAA's web site (http://av-info.faa.gov/MaintenanceSchool.asp) has a list of all schools that offer accredited programs.
• Mentors: Seek out veteran aircraft builders who have gone through the process. Most will be happy to share their experience and expertise with you. You can find them anywhere pilots congregate: EAA chapter meetings, the local airport or in flying clubs.
Exploring alternative solutions for an aircraft system.
Learning Tools: Craft
Once you have a basic understanding of aircraft technology, you can start developing your building and craft skills. To quote Louis Nizer, an English lawyer and writer: "A man who works with his hands is a laborer; a man who works with his hands and his brain is a craftsman; and a man who works with his hands, his brain and his heart is an artist."
As a builder, you need to become that craftsman and aspire to be that artist. Begin by familiarizing yourself with the tools. Every operation in aircraft
building will have its own special tools, and each tool requires specific knowledge to use it, as well as the manual dexterity to use it well.
It has been said that aircraft building is just an excuse to buy tools, and while there may be some truth in that sentiment, there is no doubt that the right tool makes the job easier—or in some cases, possible. By anticipating the type of work your aircraft will require, you can begin gathering the tools you'll need. Once you have them, learn to use them.
Tools can pose a danger to you, as well as the part you're working on, if they are used incorrectly. It is easy to irreparably damage an expensive part, so begin by practicing on scrap material until you get a feel for the tool and its capability.
Becoming a craftsman requires practice, but it also requires the right attitude. If you say to yourself, "I will be a craftsman in everything I make and be prepared to remake it if it is not up to acceptable standards," you are well on your way to becoming one. Even if you are just cutting 2x4s to make a stand to store your parts, take the time to measure accurately, cut using the right tools and drive the screws without stripping the heads. This conscientious attitude will give you a reverence for the tools and a feeling of great satisfaction in your finished product.
If you run into problems, help is available from the kit manufacturer, specialist builder assistance companies, hands-on courses at forums at fly-ins and, especially, mentors. There is nothing like learning one-on-one from a craftsman to help you become one.
Beyond mastering tools, you'll need to know about the materials you'll be working with. The most common include steel bars and tubing, various types of covering fabric, aluminum extrusions and sheet, nature's own composite material (wood), man-made composite materials such as epoxy and polyester resin, fiberglass, Kevlar and carbon-fiber cloth. Each of these has different properties and requires different tools and techniques. For example, most metallic materials are ductile (which means they deform under tensile stress) and malleable (which means they deform under compressive stress). The property of ductility means the material can be formed through bending, rolling or drawing. The property of malleability means the material can be formed by hammering, stamping or pressing. Brittle material such as plastics must be molded into shape. Composite materials combine fibers that are strong in tension with a resin that is strong in compression.
To form and combine aircraft parts into assemblies, you'll need to master the processes appropriate to the materials. In some cases this means knowing the speeds and feeds for effective drilling or machining and, in other cases, understanding the mixture ratio of plastic resins and the curing time, temperature and pressure required. Kit manufacturers explain most of this in their assembly instructions, but you'll achieve better results if you understand these processes in greater depth.
As with technology, craftsmanship with tools, materials and processes can be learned, and most of the same sources apply. Mastery of the craft, however, demands the right attitude about developing the skill and, more than anything, plenty of practice.
Using organizational tools such as spreadsheets may help keep your project on track. We'll look more into organization in the next installment.
Every day you make hundreds of decisions—what to eat for breakfast, what to wear, what route to take to work, where to go on vacation. You probably don't give the process much thought. But building an airplane requires a high degree of decision-making that starts even before you place your order, such as how you will use your airplane and what kind of construction you prefer.
There is a difference between problem analysis and decision-making. With problem analysis, you define the problem to be solved, gather information, explore alternative solutions, and identify the principles to judge the alternatives. Brainstorming at any stage of this process will help you broaden the scope of alternatives.
Decision-making involves evaluating each solution in terms of its consequences, ranking the possible solutions using selection criteria, and then determining the best alternative. While the process may seem objective and logical, the difficulty lies in how you define "best." In some cases, best may be the lowest-cost solution, while in others it may be the most elegant solution, and in still others it may be the most time-efficient. So going back to the problem-analysis stage, what is best must be defined in the context of the decision being made.
People employ many techniques in everyday decision-making:
• Prioritization: This involves weighing the alternatives according to a scale or matrix and then selecting the top choice.
• Pros and cons: List the positive and negative aspects of each alternative and choose the one with the most pros and fewest cons.
• Satisficing (combines satisfy and suffice): Select the alternative that meets a criterion of adequacy, rather than a criterion of optimum.
• Expertise: Rely on the judgment of an expert in the field.
• Gut feel: Use an emotional basis where there is a high level of uncertainty or if the facts are limited, ambiguous or incongruent with events.
• Random or coincidence: Use chance—flipping a coin or cutting a deck of cards.
• Divination: Use prayer, tarot cards, revelation or something similar.
Of course, the methods near the bottom of this list may not lend themselves to well-considered decision-making on your aircraft. Nevertheless, they are worth knowing about, if only as methods to be avoided. Notice that the lower down the list, the fewer facts are used. With a well-known quantity such as airplanes, the facts are almost always available, so it is simply a matter of how much effort you are willing to expend to find them. It comes down to education: Your learning skills and research abilities will allow you to gather the facts that are necessary to the decision-making process.
People tend to accept expert judgment as a good basis for making a decision. But the difficulty lies in deciding whether someone is actually an "expert"—does he or she have the knowledge and experience to make a sound judgment? This in itself involves a decision-making process. When an opinion is presented loudly enough, or logically enough, or often enough, it is easy to be fooled into thinking it is fact. So your first decision-making step should be to evaluate an expert's qualifications, and then to evaluate the advice.
Start screening experts by reviewing their professional qualifications in a relevant field such as engineering or aircraft maintenance: the books or papers they may have published and their reputation. The Internet, of course, is filled with opinion masquerading as fact, and it's increasingly difficult to determine an expert's qualifications. Opinions expressed on specialist online forums are probably the most difficult to evaluate unless you know the qualifications of the person posting and can cross-check the information through other sources.
If you ask for advice in online forums, be careful how you pose your question. For example, if you ask for consensus on how best to wire a panel, you may only get feedback from those people who have been wiring incorrectly. With no conflicting opinions, it is easy to conclude that their advice is valid.
The final step in your decision-making process is to evaluate the outcome of your decision as it relates to the overall cost of your project, its timeline and its effect on, or interaction with, other parts of your project. This information will guide you in further decision-making down the line.
If a group is building an airplane project, it's easy to understand the need for a project director. He or she is the person chosen to be responsible for the decisions and actions of the rest of the group. But with a more typical single builder, a project director is probably unnecessary. After all, individual builders can make their own decisions and end up with exactly the airplane they want, right? True, as long as those builders are able to make those decisions. But if they are not interested in doing the research, checking facts, developing knowledge and skills and evaluating alternatives, then the case can be made for a project director. Ideally, this should be a trusted mentor who understands an individual builder's abilities and needs.
Finding such a person may take some effort. Keeping in mind my comments on faulty consensus, your project director should not be "one of the guys in the coffee shop." They may have some experience, and will surely have opinions, but they may not have your needs in mind when they make decisions for you. It also may not be the guy with the flashiest plane on the field. He has the advantage of having gone through the building process, thus gaining the experience and expertise, but he may validate his own project by spending your money to build an airplane exactly like his.
If you decide you need a project director, take the time to make a list of your needs and wants, along with your time and budget, and then search for a trusted mentor.
Your list should include your plans and ideas for your completed airplane. If you currently own an airplane, you may want your newly built aircraft to have a higher top speed, a lower stall speed, a better climb rate, a higher service ceiling, IFR capability, to be equipped with floats or skis, or have additional or fewer seats than your current airplane. The difficulty is that unless you have a lot of experience with a variety of airplanes operating in different environments, it is hard to know just what capability you will grow into. For example, if you have only flown low-powered aircraft on local flights but plan to travel more, a faster airplane may be all you think you need. But with a faster airplane, you may find that you need IFR capability to get the most out of it. Or you may think you want a utility plane, only to discover that you really enjoy aerobatics and formation flying.
Defining your end use is critical to enjoying the aircraft that you build. As part of your education process, then, sample as many types of flying as you think you might like to do. You can take lessons from an instructor, or even beg rides with pilots who do the kind of flying you are interested in. Either way, this is less expensive than building your airplane and finding out it doesn't fit your needs as you grow as a pilot.
That's it for Part 1. Next time we'll look at organizational tools, project management and ways to keep you motivated through your build.
Terry Edwards is a mechanical engineering technologist, private pilot and aircraft owner. He is currently building a Van's RV-9A. You can bet its fuel vents will be well considered.
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