I’ve been refining my instrument panel concept over the last week. One of my goals was to fit the Garmin G5 at top center, but its size disrupts placement of other components in the center between the two G3X screens. I’ve moved the G5 to the left edge of the panel, which is where I’ve frequently seen it located on other panel designs, and this seems to work better overall for my two-screen EFIS layout.
To illustrate the layout problem with the G5, here’s the previous iteration of the IP, variant 2C. There’s less usable space on the panel; for example, I have a smaller switch panel below the GTN 650xi, and no space for the flaps switch except left of the PFD, which would make it difficult to reach from the right seat.
I’ve given some thought to using a keyless ignition, but I’m hesitant to use one of these for safety and reliability concerns.
Safety: All of the solutions I’ve found use RFID to authenticate and unlock the desired circuit (such as the starter motor). The key (usually a fob or credit card) needs to be near the antenna, and my concern is that having the key anywhere near the cockpit could enable the starter circuit, potentially endangering someone standing near the propeller. I would want to engineer some kind of interlock – maybe a seat occupancy sensor? – to ensure the starter can’t be accidentally engaged. With a traditional key, I feel safer that if the key is removed, the starter cannot be engaged, and the ignition is grounded.
Reliability: I can’t really find a solution made by a recognized brand (like Bosch). There are plenty of unknown brands available, with questionable build quality and parts pedigree. One US-based company I found is called Digital Guard Dawg (https://www.digitalguarddawg.com/keyless-ignition/marine/pbs-m/) and their product for boats might work. I’ve reached out to them to see if they’d make any statement about suitability for use in an airplane.
Based on these factors, I’ve decided (for now) to use a traditional keyed ignition switch from ACS and a separate starter switch, which are below and above the Garmin G5, respectively.
Additionally, I refined the designs for my custom switch panels: one for the flaps control, and another for various electrics including locking toggles for master power & engine control unit (ECU), and tactile pushbuttons for accessories. The two toggles are a locking variety, meaning they need to be pulled out to be moved, preventing accident bumps of the toggles in flight.
I ordered some translucent acrylic material to experiment with backlighting, and I’ll work on a circuit board design to go behind the panel.