We spent six weeks building and testing a 20ft Ekranoplan ready for its sea trials!
If you want to see the whole video you can check it out here:
The Caspian Sea Monster was a famous USSR ground effect plane that would glide across the sea on a cushion of air which was a huge reduction in friction when compared with normal ships.
This project was inspired by this aircraft. Could we build our own giant ground effect plane?
To start with, we would need to make a prototype model and use it to figure out how difficult a larger scale model would be. Using foam board and RC plane electronics, we had our very own mock up of the sea monster.
A test on solid ground first would give us a good idea how this design would work on water without having to risk losing all the work we had done so far and with a few adjustments, the ekranoplan glided across the field as expected.
Our model was ready for its first test on the water, so we headed down to Rudyard Lake. Even with the increased power required to pull the model out of the friction of the water, the ekranoplan continued to meet our expectations.
Happy with the design and the results of the tests, we got to work assembling our larger model. The fuselage, bulkheads, wings and tail would be made from 2.4cm thick insulation foam with some reinforcements where necessary. Due to the size of the fuselage, we had to relocate to the VAB to continue with the wings, tail and electronics.
The wings were made from a sheet of the insulation foam with a root and a tip made from XPS foam. To cut these specific curves, Emma made a hot wire cnc cutter.
The machine pulls a heated 0.4mm nichrome wire through the foam, allowing the material to melt before any force is applied to the wire and consequently the motors. The pair of motors on each side of the machine directs the wire into following an airfoil pattern.
These roots and tips were glued on to the rest of the wing which was installed and reinforced with carbon fibre rods courtesy of Easy Composites who also provided us with the XPS foam.
With the majority of the ekranoplan assembled, it was time to fibreglass the outside, both waterproofing and reinforcing the whole thing, a process that took us an entire week. We used XCR resin also generously provided by Easy Composites.
With the fibre glassing complete, we could move on to the T-tail. For transportation purposes, it needed to be removable which added difficulty to the build but we settled with a peg and lock system which worked quite well.
Next was the motor mount. This behemoth was going to be propelled by four brushless motors and they needed to be attached firmly to the fuselage.
After some last remaining jobs, such as the heavy-duty servos for the rudder and elevator, the ekranoplan was almost ready for its first test.
Now all we had to do was wait for some low winds and good weather to take the ekranoplan over to the test field.
First up was a test hop. Before any big distances, we just wanted to see if it had the power to lift itself away from the ground and "hop" a small distance. Even with this being the heaviest project we've made so far, it had no problem with its first ever hop.
Now we needed to see how well it moved and as the motors pulled it forward, it glided perfectly across the field. The tests were a success and the ekranoplan was performing just as we wanted it to.
Next up is the water tests! Keep an eye on the channel for updates on how this ekranoplan copes on Rudyard Lake and in the meantime check out some more project articles here!