Re: on EFIS Placement and redundancy
Having owned a '41 T-Craft w/ no electrics the thought of just having a starter is high tech in my mind.
However, after talking the redundancy issue over with a number of people who have installed Dynon units and other EFIS displays I’ve decided to install a wet compass, airspeed indicator, altimeter, and slip ball. (What the heck, the balls are cheap enough.)
That is for a day/night VFR ship. If my RV-9 was going to be IRF equipped I doubt I would add much more.
Before you can really answer the question of what redundant equipment is needed, you have to look at your mission profile and comfort level with flying with minimum instruments. I’m probably one of the few pilots left in the world that have never flown with a GPS but plan on installing one in my -9. Will I use it for a back instrument? I won’t know until I fly the airplane.
The Dynon units are proving to be very reliable but one of our chapter members had an over voltage condition on his first flight and his electrics went Tango Uniform on him and he had to land w/o any airspeed indications on his first flight. Not a situation I want to find myself in. (The cause was a new alternator that was faulty.)
I also hope to equip my -9 with the Dynon EMS w/o back up. I figure if the EMS goes south and that big chunk of aluminum out front continues to make noise, then I’m in good enough shape to find the closest airport. On the other hand, if every thing goes silent on me then what good is the EMS unit going to do for me. I will already know the RPMs will be zero along with the oil pressure and a few other important readings. (You would be surprised at how many pilots think that is crazy.)
Again, it comes down to your mission profile and what you are comfortable with.
BTW, there are some pictures of what I think my panel might look like on my web site. Let me know what you think after looking them over. I value everyone's input on this subject.
Bill
www.repucci.com/bill/baf.html