Deadline: 8am Thursday January 27. Bring your assignment to class if you have not already left it in my mailbox.

1. A high-winged aircraft is to have  a gross weight of 10,000 lbs at cruise. Its wing span is 60 feet, and the wing loading is no more than 50 psf. The wing airfoil section is NACA 0015 throughout (very simple design) and twist, if any, has to be linear twist.

You are to design the wing, and calculate the angle of attack of the midspan section, for a cruise flight condition at 140 mph at 5000 fee ISA. 

Also calculate the induced drag of the wing, and hence the Lift/ (Induced-Drag) ratio of the wing.

Please look up a realistic value for the Profile drag coefficient of such a high-winged, propeller-driven aircraft. Use this to find the flight speed for minimum drag at  5000 feet ISA, and compute the L/D ratio of the entire aircraft at this speed.

Please convert all values to metric and do your calculations in metric.
 

2. Determine the properties of carbon dioxide gas, and find the atmospheric conditions near the Martian equator, at a height of 10,000 feet above the surface, on a summer day. (Hint: spend some time surfing the 'Net, especially NASA pages, use the Space Sciences link from the Resources page under  www.adl.gatech.edu as a starting point.)

We are going to think about a Martian aircraft this semester.  As a starting point, please calculate how fast one has to fly at this altitude,  to achieve a wing loading of 50psf.

Assume that you have to limit the angle of attack of a flat-plate airfoil to about 10 degrees, max.

For simplicity, forget about tip losses and aspect ratio effects, and use  a 2-D calculation for wing lift   (I know,  there are no 2-D wings, but here I think you will have to fly supersonic, so the approach of the above problem cannot be used).