Approaching the Design of a Scaled Flying Test Bed of a Convertible Martian Aircraft

It seems that each following step in our LEMFEV journey brings about new exciting challenges - new opportunities to learn and craft useful knowledge-based tools to share with students and peers.

Two years ago, we embarked on this design journey with something indefinite and vague...

You see, from the very beginning, we considered two wing configurations - wing-tail and boxwing, and we tried our best to fit them inside an aeroshell:)

To give the airplane shape and size, as well as its heart, the powerplant, we invested a great deal of time and effort to collect relevant data on the existing Martian aircraft projects and on the expected conditions in the beautiful but unkind world where we expect it to fly.

In the meantime, we learned oh so much! Just to name a few points:

How to size a rocket-engined airplane? ...

... how to check the energy balance of a day-night solar airplane? ...

... what a variety of low Reynolds number airfoils one might imagine! Including undercut and other bird-like airfoils (just look at sample early bird-like airfoils shown below).

We had to learn how the Martian atmosphere can be modeled ...

... what is the critical Reynolds number and why any aircraft would prefer to travel at 'supercritical', rather than 'subcritical' Re?

Our airplane is maturing with our growing expertise and with each new team member.

And we are learning to make the most of increasingly complex and versatile design and analysis tools.

So, we have reached at the final configuration - solar convertible boxplane as a secondary payload, with a wingspan of approximately 1 meter.

This airplane will carry a little research station from cite to cite or conduct in-flight measurements in the planetary boundary layer.

And now, when we are designing our flying test bed, we discover that there are so many huge areas to be explored! The most important are:

• scaling wings and propellers,

• matching the airframe, motor, and propellers for a convertible airplane with two so distinct modes of flight, and

• designing the flight test program.

This sounds terribly interesting, right? So, stay tuned!