A couple of weeks back, there were lot of posts on question of flights and aerodynamic design in OURAeSI. At that time, being busy, I couldn't answer them but now I took up the task of answering the ones I can.
But strangely, I think, people who are asking this questions haven't done a little research by themselves on net. Because wikipedia and all the useful resources accessed through the use of Google has all the answers they are searching for...
So folks don't be lazy. Try Google and wikipedia before submitting.
Anyway it’s good that OURAeSI club is being used for the questions. That is encouraging, it seems now not only job seekers but students are flocking to the club and are asking what matters to them the most.
Keep it up guys and also do share about how were the exams. What was good and what went wrong? Just a line and two can begin the discussion. So chip in.
And for the question someone asked about Fuselage Fineness Ratio. So here is what wikipedia has to say.....
Fuselage Fineness Ratio
Fineness ratio is a term used to describe the overall shape of a streamlined body.
Specifically, it is the ratio of the length of a body to its maximum width; shapes that are "short and fat" have a low fineness ratio, those that are "long and skinny" have high fineness ratios.
Aircraft that spend time at supersonic speeds generally have high fineness ratios, an example being the Concorde and missiles.
At speeds below critical mach, one of the primary forms of drag is skin friction. As the name implies, this is drag caused by the interaction of the airflow with the aircraft's skinning. In order to minimize this form of drag, the aircraft should be designed to minimize the exposed skin area, or "wetted surface", which generally implies the fuselage should be somewhat "egg shaped".
As an aircraft approaches the speed of sound, shock waves form on areas of greater curvature. These shock waves radiate away energy that the engines have to supply, energy that does not go into making the aircraft go faster. This appears to be a new form of drag —referred to as wave drag. In order to minimize the magnitude of the wave drag, the curvature of the aircraft should be kept to a minimum, which implies much higher fineness ratios.
