Development of the DarkAero 1 prototype continued in June with new progress on the aft avionics module, pitch control system, and battery cooling box. In parallel, we continued on the remaining tasks to complete the engine installation, seat fabrication, and nose gear components. We also gained another member of the team, Carter DeSpirito, as an intern for the summer. 

Seat Fabrication
Ryan finished construction on the first pilot-side seat cushion and proceeded to upholstering it. For the prototype aircraft, we decided on a simple cushion design that is constructed from varied layers of Confor foam. Each seat cushion is split into two sections: a seat back and a seat bottom. The seat structure that supports the cushions is fixed in position and is integrated into the airframe so builders will customize their seating position by adjusting the shape and thickness of the seat cushions and by moving the rudder pedals forward or aft. Given the custom-fit nature of the seats, the cushion fabrication will be a builder task. Our prototype cushion design is comfortable for a wide range of pilot sizes so we will be sharing the design details of our cushions for builders to use as a starting point in their aircraft.

Aft Electronics Module 
The last remaining section of the electrical system architecture we built was the aft electronics module. The unit is fastened on a set of composite rails in the aft fuselage behind the main gear wheel well. It is installed and accessed for service through the main gear doors and held in place with Click Bond studs. Mounted on the module are the remote communication radio, primary ADAHRS, and backup ADAHRS. These components were placed in the aft location to minimize pitot and static line distances as well as the coaxial lines to our antenna array. Electrical and pitot/static line connections to the module are made with quick disconnect couplers. 

Elevator Pitch Control System
The DarkAero 1 control system utilizes dual side sticks mounted in the arm rests. The pilot and copilot pitch control components are tied together with a carbon fiber torque tube positioned below the aft baggage floor. We fabricated the last of the components for the elevator controls and started installing them into the fuselage. An integrated servo bracket is included in the system to accommodate the standard Garmin, Dynon, or TruTrak autopilot servos. 

Engine Installation
We continued through the remaining details of the engine installation. Ryan built up the battery cooling box that was discussed in the May 2020 update. Carter built the oil dipstick door and started on its hinge and latch mechanism. The fuel pumps were mounted which allowed us to fabricate the fuel lines to connect the pumps to firewall bulkhead fitting. We also cut out the titanium firewall heat shield and installed blind Click Bond nutplates on the cold side of the firewall. The heat shield work required that we remove the engine from the firewall. While the engine was removed, we weighed the engine and its accessories to double check that everything still agreed with our predicted weight and balance numbers. The assembly was within a pound of our targets, which is significant because the power plant and its associated systems make up over one third of the aircraft empty weight. 

Nose Gear Assembly 
After the recent redesign of the nose gear retract mechanism, we machined out the rest of the new nose gear components and assembled the nose gear. The nose gear is now nearly complete. We performed an initial mock assembly of the nose gear and tested it through its range of motion for strut compression and retract/extend. We were pretty pleased with how everything fit together and assembled. There are a few small design changes for production we have documented that will improve the assembly process for the gear. 

Instrument Panel Fit Up
One of the distinct features of the DarkAero 1 cabin is the instrument panel structure. It is mounted to the canopy frame and hinges up with the canopy to ease ingress and egress from the cabin and provide access to the forward baggage compartments. We finished up the canopy hinge structure which allowed us to mount the instrument panel into the fuselage and get a more complete feel for the cabin ergonomics and accessibility. We will be adding gas springs that will help lift the canopy and instrument panel assembly, as well as hold it up when the canopy is open. 

YouTube
We released two new YouTube videos documenting the construction of the DarkAero 1 prototype.  If you haven’t seen the latest videos yet, we recommend heading over to our YouTube channel to check them out.

UL Power UL520iS Engine Install on the DarkAero 1 - Part 1

DarkAero Shop Life 8 - Firewall Heat Shield, Battery Cooling, Avionics, Nose Gear - Jun 19, 2020

We also recommend subscribing to our YouTube channel to stay up to date on the latest content we release.

DarkAero YouTube Channel: https://www.youtube.com/darkaeroinc

In The Press

The DarkAero project was recently featured in an article on the University of Wisconsin-Madison College of Engineering news page.

Click here to view the article. 

Looking Ahead
We have a lot of systems and projects that are nearing completion in parallel that we hope to wrap up in July. We are planning to perform the nose gear drop tests, begin manufacturing the main gear, finalize the installation of the control system, electrical system, and install the propeller. Normally we would be gearing up to head to EAA AirVenture at the end of July but with the event being canceled this year, we will be doing some more YouTube and social media projects to connect with the aviation community.