I'm curious as to how it is possible to avoid going under the panel if the airframe is already complete? E.g. there are all of the engine sensor wires that need to be routed through the firewall; power wiring; control cables from panel to heater and parking brake valve; engine and prop control cables; coax runs for comm and transponder; audio wiring to jacks. Then there's also all of the securing with adel clamps, cable ties etc.
I managed to do all of this without crawling under because the fwd skin was off and access was easy just standing beside the fuselage and reaching in. Most harnesses and sub-harnesses were completed on the bench but good access made it easier to get the lengths right. I know the Van's traditional build manual implies to complete the airframe before the panel but I don't see how it's possible to do that without crawling under?
Yep - so you did all this with the forward skin off. What will you do for maintenance, updates and such.
You can avoid this pitfall if you first divide everything into:
- Stuff that says in the plane
- Stuff that stays on the panel when it comes out of the plane
The RV-8 and RV-10, if built to plan, provide a nice way to divide this up. The side wings on the RV-8 or the lower apron on the RV-10 stay in the plane. Here is where you mount most switches and breakers. With the panel out you have easy access to it all, as well as engine control cables and such.
On planes like the RV-6 you can do the same approach if you first make a lower apron. We just did this on an RV-6 that is getting new dual screen SkyView install. Not hard, just aluminum, nut plates and rivets. Engine controls are mounted on a piece of bent aluminum attached to the bottom of this apron. XPDR, EMS, ARINC, Dynon remote radio and such are mounted behind the panel on the next forward bulkhead. Again - all within easy reach when the panel is out of the plane.
The biggest pain on the panel is the radio stack, and especially the audio panel. If the panel is on the bench you can now have a cup of coffee when working it.
Some planning goes into this, but once you break the code it is very easy.
For photos PM me your email address.
Carl