About a mile from Wichita Mid-Continent Airport, inside a nondescript building that looks just like any other in this part of town, a small group of workers toils in secrecy against the whir of band saws, banging of hammers and buzz of automated cutting machines. This is Cessna’s interior design research-and-development center, its cabin “Skunkworks,” if you will. This is where various cabin concepts are tested and where rough and finished mockups are created. The importance of this modest-looking facility, said the manufacturer, cannot be overstated.
“We pride ourselves on trying not to show mockups that aren’t representative of the end product,” said Cindy Halsey, Cessna’s vice president for interior design, engineering and development. “We don’t use mockups as a bait-and-switch kind of thing. In my 15 years at Cessna, it just amazes me how many aircraft we sell off the mockups. It is really a responsibility to our customers.”
Inside Cessna’s nearby Wichita showroom, an atrium-like expanse crowded with mockups, customers climb in and out of them as they might at a car dealership. Gary Sauber, Cessna’s manager of interior design, research and development, runs the cabin mockup workshop, and it is a busy place. Last year, workers there produced show-quality mockups for four different aircraft: the Large Cabin Concept, the Citation XLS+, the CJ4 and the NGP (New Generation Piston).
“We wouldn’t have been having this conversation last year,” Sauber said flatly. “I didn’t have the time.”
Sauber might seem an unlikely design chief. After graduating from Kansas State University he went to work for Boeing writing maintenance manuals. He then joined Cessna where he worked on cabin electrical systems and later became the interior design group liaison before going to work for Halsey. Sauber told Halsey he wanted to focus on R&D, so six months later she created the interior design group and placed Sauber at the helm.
Ask cabin designers who their greatest influence is and some might name architects such as Frank Lloyd Wright or Philip Johnson. Not Sauber. His is Bill Gates. “Gates thinks outside the mainstream,” said Sauber. “He is willing to try different things and take risks.”
Mockups go through several stages
before they are presented in public at a forum like the NBAA Convention. “Computer programs tell you a lot,” Sauber said. “It can show you what the cabin is going to look like and you can even put mannequins in there and the program will tell you if the design meets the requirements. But nothing beats a physical mockup for actually being able to crawl in there and see for yourself.”
A wooden “human factors” mockup is the first step. Rough mockups initially may be nothing more than half-sections or cutaways of wooden fuselage frames with rough foam shapes inserted to represent positioning of seats, tables and other cabin furniture. This seemingly crude device allows Cessna to quickly plug-in different seat sizes and shapes, tables and window locations. Some of these rough mockups even have adjustable fuselage diameters. “We can alter tube size, with different diameters,” said Sauber. “We can get instant feedback on how different seat spacing and aisle widths feel.”
Advanced computer programs define “safe zones” or windows within, where seats, windows and doors can be placed without altering basic aircraft structure or crashworthiness. It also makes crashworthiness testing of key cabin components, such as seats, less of a guessing game, according to Sauber. “It allows us to have a pretty high confidence level that we will pass before we run the actual tests,” he said.
Sauber said Cessna designs its cabins to accommodate the 50th percentile female and the 95th percentile male. “That’s 99 percent of the population,” he said.
However, Sauber insisted that there is still no substitute for good-old-fashioned butt-testing in the seats. He pointed to a wooden frame he won’t identify but that looks suspiciously like the cross section of Cessna’s LCC mockup. “Most of the components you see in there are not in the correct location for what you would see in a production aircraft. But we get the diameter right so we can hang stuff in there and get feedback.”
Cessna conducts extensive “voice of the customer” research with all its airplanes, and Sauber’s group works closely with the company’s marketing department in this effort. “We may build three of them,” Sauber said of the wooden mockups, “before building a full-tube mockup” such as you would see on the NBAA show floor.
Sauber’s group also looks at advanced materials like “memory foam” for aircraft seats, or typographic processes that simulate wood grain veneer. Cessna used the simulated veneers on the Citation Mustang to save weight and increase durability. Sauber sees the Mustang interior as his group’s finest achievement to date. “Everything about the Mustang turned out better than we thought,” he said.
“We’re working on a lot of things,” he continued. “Some go right into production, like in the Mustang, and others are just pure R&D.” Some of that R&D can have a very long shelf life. For example, according to Halsey, Cessna first looked at a Large Cabin Concept airplane in 1995.
However, most projects have a more expedient development cycle. Sauber credits computer modeling and Cessna’s ability to quickly fabricate stereolithic or composite parts for its mockups.
Although data driven, there is still a fair amount of artistry when it comes to building finished mockups. “These guys down here are skilled craftsman and they know every possible trick on how to make the mockups look real,” he said.