Last week, EAA received an e-mail from John Brown, project manager of Carplane, a German government-sponsored aviation firm developing a roadable light-sport aircraft, regarding an analysis of about Scaled Composites Model 367 BiPod.
John writes, “Our team got together last week to analyze what's currently known about Burt Rutan's BiPod. (Attached are our thoughts.Rutan BiPod, Analysis.pdf) It appears there have been 5 BiPod versions within the first week, some of them morphing between conventional 2-surface & advanced 3-surface configurations. Furthermore, neither the measurements nor some of the claimed attributes seem to add up. Perhaps your editors could shed light on some of these questions.”
Brown’s comments about changes in the first week seem to be a reference to the first story EAA ran on the BiPod on July 17 (which was updated on July 20), and the more complete story that ran in July 28 issue of AirVenture Today after Burt gave a homebuilders chat about his latest design during AirVenture Oshkosh 2011.
When asked for a comment on Carplane’s analysis, Burt wrote EAA, saying:
“Time does not permit a detailed answer to this PowerPoint. However, for now suffice it to say that he has made many wrong observations based on poor measurements of photos or graphics. The BiPod, in phase one testing has proved itself on the skid pad and at freeway speeds in strong crosswinds to be a very road-worthy vehicle. Gee, he complains that we have too much drag as a car but not enough drag as an airplane!!!
“Note that I am breaking my rule here by paying any attention to his analysis - I usually have a rule to comment only things that are flying, not someone's untested concept. The carplane, like the TF, will likely have very poor airborne performance and efficiency as well as a very noisy, high vibration propeller with blades that move in and out of the wake of forward components (Like my old VariViggen). Like I said at Oshkosh; if you cannot cross the Rocky Mountains to get to Oshkosh, you really do not have a practical airplane.
“I will have no further comment until after we have a race....both in the air and on the ground."
What are your thoughts?