In the next few assignments, we will be looking at some concepts and design analyses needed for future high-speed aircraft.  Several applications arise. For example,

a) rotorcraft where the blade section changes as the blade goes round, using materials that respond to electric current by changing dimensions, or blade sections whose shape is changed using pressurized gases transferrred between compartments.

b) small, "autonomous" (robotic) high-speed aircraft which are released from a  larger mother-craft, and fly in to perform missions which cannot be performed by humans. ( Lockeed Uninhabited Combat Vehicle, UCAV, or concepts for Mars gliders)

c) transport aircraft whose external shape changes to keep pressure distributions optimal over the entire flight regime.

1. The first issue to deal with here is to design a wing section shape which continually adapts to changing Mach number. When the aircraft is flying at Mach 0.8, we want the wing section to have a thickness-to-chord ratio of 0.05.  Plot how the thickness to chord ratio must change, if the pressure distribution shape is to be kept constant as the aircraft speed changes from Mach 0.8 to Mach 0 (incompressible). We will have an "adaptive, inflatable wing" which changes section thus to maintain the same pressure distribution.

2. Decide on an airfoil type. Investigate what kinds of airfoils are used today for high-speed aircraft.

3. Once you have decided the thickness-to-chord ratio at the incompressible case, find the pressure distribution of this section. You can do this using the data given, for example, in the book "Airfoil Sections" by Abbott and von Doenhoff, or look on the ADL "Digital Libraries" link for the NASA Reports Server and hunt for reports on airfoil data, or use one of the "calculators" or data sources given in the "Aerodynamics/Fluid Dynamics" link under "Aerospace" in the "Resources" page.
 

The nominal deadline for this part is next Tuesday.  However, this assignment need not be turned in at this stage. You are each to construct a web page, post your work there, and just e-mail me the link to your page. As the semester progresses, other problems will be solved, which we hope will contribute to the overall development of aircraft for high-speed flight.

Please realize that this is a "discipline/motivation trap", though not evil-intentioned.   The risk in not keeping up is, of course, that you will quickly get left behind. So, please keep to the deadlines.