The new year at DarkAero was kicked off with exciting progress on systems and accessories in the DarkAero 1 prototype! Efforts in January were focused on the canopy, electrical system, spinner, and landing gear. 

Canopy Progress
We are pleased to report that we took delivery of our first canopy from Airplane Plastics! Using the preliminary mold we handed off at the end of 2020, the team at Airplane Plastics completed the remaining mold structure and were able to produce a canopy with superb optical clarity. The canopy was formed from acrylic with a light smoke tint and was rough trimmed when we picked it up. We have been trimming the edges to final dimensions which is a critical step because the trim dimensions we establish will be used by Airplane Plastics in the future when they produce production canopies. We are excited with the result so far and we are working through the details of integrating the new canopy with the rest of the canopy frame. Arriving at a solution for canopy manufacturing represented a major milestone in the project. Previously, a lot of time and energy was dedicated to sorting out the problem of manufacturing a canopy. At times, the whole team was involved in the project, but now all that effort can be shifted into the next steps for completing the prototype aircraft.

Electrical System Update
If you’ve been following along with the DarkAero project, you may know that the electrical system is broken up into several modules that are interconnected with a wiring harness. We have been working back and forth between doing fit checks with the harness in the aircraft and making changes to it as we learn more. The side of our cure oven has continued to serve an important role in giving us a location to stage the harness to test it and rewire it. This month was the first time we were able to connect each individual module to the harness and perform connection tests between each module. These tests will allow us to validate the functionality of the entire harness prior to doing a final installation in the airframe. Over the next several weeks we will be adding more components to the harness including our landing gear linear actuators and pilot headsets ports. We will not only be confirming component connectivity but also running through various conditions to look for signal noise, check for overload conditions, and look for improvements that will increase reliability of the harness. 

Firewall Forward
Continuing our propeller work from December, we finished building and installing the spinner on the hub of the Airmaster propeller. Tasks included making new forward and aft bulkheads to support the spinner, cutting openings in the spinner for the propeller blades, installing fasteners, and fitting the assembly to the propeller hub. The prop controller was powered up and we ran the propeller blades through their full range of motion to confirm clearance between the blades and the spinner. We documented more details of the spinner design, manufacturing, and assembly in a YouTube video linked below.

Carbon Fiber Spinner Design & Install on the DarkAero 1

The propeller and spinner assembly represented one of the last big systems to install on the firewall forward section of the DarkAero 1. With this complete, we were able to move the engine back into position on the firewall for another fit check on the engine accessories before installing the firewall insulation and heat shield. It was exciting to see the full profile of the spinner, propeller, cowling, fuselage, canopy, and vertical stabilizer all together for the first time. The engine will be moved on and off the firewall a few more times as we finish the final details of the firewall forward package.

Landing Gear
Progress continued on manufacturing various components for both the nose gear and main gear. The struts for the main landing gear legs were infused and trimmed to final dimensions. The mold for the nose gear doors was CNC machined and prepared with mold sealer and mold release. The hinges and hinge mount components for the nose gear aft doors were finalized and CNC machined out. We also CNC machined locating templates to accurately position the hinges. For production, the hinge location will be CNC cut into the bulkheads themselves so builders will know exactly where they need to be installed. Additionally, more of the necessary gear hardware was sourced and ordered for the prototype. In February, we are looking forward to installing the nose gear doors and hinges into the aircraft. 

Finalized Prototype Development Schedule
At the beginning of each year, we sit down and do a revisit of the goals, milestones, and overall schedule for the DarkAero 1. As we near completion on the prototype, we recognize it is especially critical to manage our time and resources to stay on schedule for flight testing this year. For 2021, we are experimenting with a new scheduling method that mimics the system used by the engineers at North American Aviation as they developed the prototype for the P-51 Mustang. We hung up a large copy of our new development schedule on the tool cabinet doors so that it is in clear view at all times. It was a simple change, but it has already driven more organization and focus in order to get the airplane completed faster.

Looking Ahead
In February we will be continuing with the last remaining firewall forward tasks, installing the nose gear doors, and finishing validation of the avionics network.