The main point of this work is to figure out what exact influence on the cargo landing have layout parameters. Also we have to define the most appropriate zone for cargo landing. Making some research of similar unmanned aerial vehicles we can notice that should be somewhere behind the fuselage. But our goal is analytically to prove that.

To start we ought to define things can cause the drag; discuss about ways of reducing those; making a conclusion to choose the most appropriate way to solve all negative issues.

We have several things causing bad influence on the unloading process. First of all, wingtip vortices caused by wing and vortices caused by the fuselage (inductive vortices). Second thing is inaccuracies in starting system such as sags and design flaws. And if may neglect the second point we definitely have to pay attention to the aerodynamic effects.

Firstly, let’s figure out why mentioned above vortices cause drag.

That movement of the air is work done by the wings, or more precisely, by the engines pushing the wing through the air. That work is not useful work. It is just spinning the air behind the plane, like stirring the water in a glass. (It also creates a low pressure zone in the middle of the vortex, i.e., a very weak vacuum, which is another kind of work the engines are having to do.) It is not helping to push the plane up into the air. So that useless work increases the load on the engines without helping to make the plane fly. Moreover, in our case it can also tangle slings of exhaust parachute and cargo would be unstable during whole landing.

Thus, we must to reduce an impact of those vortices toward a parachute and the cargo at all. In this work that offered to perform by lifting the wing upon the pylon. Thus, the airflow supposed to pass without “touching” the cargo box also skirting the unload zone. At this time, I consider wing effects on the cargo one way or another is solved.

Going forward, we should not forget about the vortices caused by the fuselage. The have almost the same nature. But what if we would use that bad effect, as we thought previously, for solving our issues. Let’s see what we can do. It has been proposed to use specific fuselage fence. That decision can help not only reduce influence but can direct the backwash toward the direction of the unloading.

Thus, we have two oppositely directed vortices flowing down the fuselage which can help to protect slings of parachute from the tangling and can provide us with safety zone for unloading from the point of aerodynamic.

Making a conclusion, we have overviewed two reasons of appearing factors interfering the unload and landing processes. It has been proposed the way of resolving those issues and justified that is going to be an optimize way to reach the goal.