A NASA render of a SAW wing at extreme articulation. (Image courtesy of NASA.)
In collaboration with Boeing, and Area-I, NASA engineers have begun work on a Spanwise Adaptive Wing (SAW), a type of wing that can be folded perpendicular to the length of the foil itself. While wings have traditionally been designed with an unflappable shape, engineers at NASA believe that articulating wings could give pilots greater control over their craft and create energy efficiencies that can’t be realized through other design methods.
To build this SAW NASA’s team will use actuators to give the outermost third of the SAW wing a hinging mechanism that can bend up to 75 degrees.
“Ideally, we would be able to take that portion of the wing, and articulate it up or down to the optimal flight condition that you’re in,” explained Matt Moholt, NASA Armstrong principal investigator for SAW. “So let’s say you’re a condition that requires a climb-out. The optimal position might be up 15 degrees or down 15 degrees, and you would be able to get that.”
The PTERA testbed. (Image courtesy of NASA.)
Prototype-Technology Evaluation and Research Aircraft, or PTERA, featuring the actuated wings could be deployed as early as Spring 2017, but if you think SAW technology is a new concept, think again.
According to Moholt, the idea of folding wing aircraft has been around since the middle of the twentieth century, it’s just that the technology wasn’t.
“We are revisiting folding-wing aircraft because new technologies that did not exist in the 1960s allow actuation to be put in tighter wings, in smaller volumes,” said Moholt. “Now you can articulate a very small, thin air foil, whereas before the actuator technology didn’t exist.”
Depending on the results of the initial PTERA tests NASA will begin even more advanced SAW tests that employ actuators more consistent with those that would be used if a SAW plane were put into production.
For another example of the possible future of aerospace, meet NASA’s new electric X-plane.