2024 ARP Catalog

14 THE “AEROSPACE QUALITY” MYTH In areas from hose ends to engine fasteners the terms “Aerospace material and Aerospace Quality” have become buzz words implying the very best in design, materials and quality control. “It isn’t necessarily so”, says Gary Holzapfel, founder and CEO of Santa Paula, California based ARP, Inc. ARP (Automotive Racing Products) supplies extremely high strength and fatigue resistant threaded engine fasteners to NASCAR, IndyCar, NHRA, IMSA and Formula 1 engine builders and manufacturers. Holzapfel explained his reasons in an interview with Carroll Smith. Smith: “Gary, do you believe that the term “aerospace quality” is over rated in the specialty fastener industry?” “Yes I do. First of all, the term is meaningless. Any AMS (Aerospace Material Specification) material must be matched to the specific application. As an example, some airframe bolts (AN3-20) are legitimate “aerospace parts” and are very well suited for the low stress applications for which they were designed. But with a minimum ultimate tensile strength of 125,000 psi, and a relatively low temperature limit, they would be completely unsuitable for use in a racing engine. We started out in the aerospace fastener business and we understand it. That’s why we’re not in it any longer. What is not generally understood about aerospace fasteners is that the fastener manufacturers do not design the product. The nuts, bolts and studs are spec’d by the airframe or engine designers and put out for bid. As long as the supplier certifies that the product meets the minimum requirement of the specification and it passes the customer’s inspection procedures, low bid wins.” Smith: “Are you implying that the aerospace fastener manufacturers cut corners in order to win contracts?” “No, it’s a matter of manufacturing goals and simple economics. The aerospace market is price dominated. In order to get the contract, the fastener manufacturer’s goal is to meet the specification at the least cost, not to produce the best possible part. This means that they are going to use the least expensive steel and manufacturing processes that will meet the specification. There is nothing wrong with this approach. It certainly does not mean that certified aerospace fasteners are unsafe in any aspect. They will do the job for which they were designed. There is another factor. Airframe and aircraft engine manufacturers design their components to a very high margin of safety. Further, aerospace structures are designed to be “fail safe.” There is a back up or second line of defense for virtually every structural component so that an isolated failure will not lead to disaster. They are also subjected to frequent and rigorous inspections.” Smith: “What’s different about motor racing?” “Quite a lot, really. While the demands for strength, fatigue resistance and quality control can be similar, and the assembly and inspection procedures in racing can be as rigorous as aerospace, in professional racing very few parts are over designed and there are no fail safe features. FASTENER TECH