For over half a century, kits have been sold that enable military history buffs to assemble scale models of military ships, aircraft and vehicles. But that era is coming to an end, as the manufacturers of the original equipment, especially aircraft, are demanding high royalties (up to $40 per kit) from the kit makers. Since most of these kits sell in small quantities (10-20,000) and are priced at $15-30 (for plastic kits, wooden ones are about twice as much), tacking on the royalty just prices the kit out of the market. Popular land vehicles, which would sell a lot of kits, are missing as well. The new U.S. Army Stryker armored vehicles are not available because of royalty requirements. Even World War II aircraft kits are being hit with royalty demands. 

These royalty demands grew out of the idea that corporations should maximize intellectual property income. Models of a companys products are considered the intellectual property of the owner of a vehicle design. Some intellectual property lawyers have pointed out that many of these demands are on weak legal ground, but the kit manufacturers are often small companies that cannot afford years of litigation to settle this contention. In the past, the model kits were considered free advertising, and good public relations, by the defense firms. The kit manufacturers comprise a small industry, and the aircraft manufacturers will probably not even notice if they put many of the model vendors out of business. Some model companies will survive by only selling models of older (like World War I), or otherwise no royalty items (Nazi German aircraft) and ships. But the aircraft were always the bulk of sales, and their loss will cripple many of the kit makers. Some of the vehicle manufacturers have noted the problem, and have lowered their demands to a more reasonable level (a few percent of the wholesale price of the kits).