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Do what yer' Momma said...
Go Play!
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What I would do next time - View Thread
Having a nearly completed 9A (I hope to have it signed off Sunday) I thought I'd share a few painful building experiences. I started with a quickbuild, both wings and fuselage. One difficulty with the QB process was determining what had been done and where/how to continue. But once that was sorted here are some issues that I suspect are common to all projects:
Wingtips - Once I had everything installed and aligned I found my right wing tip were out of line even though I thought I had them aligned perfectly at that stage using the alignment method in the plans. You will have to have the trailing edge aligned with the flaps and aerlion's across the span when everything is done, so why not wait to make the necessary twists and adjustments of the tip before drilling it, until then. If your alignment is off, as mine was, you will be faced with the prospect of removing the rib, splitting the trailing edge and possible the outside as well and reglassing it, at a point when you thought you were almost done.
Wait until you have the entire wing installed and aligned before you drill and install your tips. Step Kit - On a 9AQB you will have to remove and reinstall baggage compartment floor panels to add the step kit. Why Van's doesn't include the step kit as part of the standard "A" kit is beyond me. Have you ever seen a trigear without steps? There are several tri-gear specific issues that make this verison more challenging to build, IMO. Mounting the wings is a memorable experience. since the lower wingbolts are "almost" impossible to install, let alone torque to spec.
Wing tank brackets - Ignoring the hassle of fabricating these brackets from 0.125 angle, (the RV7A uses a preformed steel bracket) don't bend or drill the flanges until you have the wings installed aligned and the rear spar drilled. Then attach the brackets and bend to obtain the optimum alignment with the fuselage attach points. Drill the attach holes from the cabin side insuring that the holes center in the flange of the angle on the fueslage side.
Nose gear attach bolt - Don't bother to drill the hole in the firewall for the nose gear bolt. It will install just fine top down from the firewall side with just enough clearance to attach and torque the bolt.
Oddysey Battery option - highly recommended both for weight savings and size, but make sure you leave sufficient open space on the firewall above the battery to remove it for service or repacement.
Tipup canopy fit - Lot's of luck on this one, but if it is even close don't sweat it, that's what bondo is for.
Brake lines - forget all the warnings about not using teflon tape. With attention to avoiding excess, use it on all your fittings to the brake cylinders. Everything else will leak leading to endless cycles refit and brake bleeding.
Wing wiring - Leave ample, 2-3 feet of nonterminated wire at the wing root. Plan on making connections under the cabin floor after the wings are installed and torqued to spec. Wing wiring gets in the way otherwise. Make sure to label the wires in a permanent manner, don't use pieces of tape!
Fuel lines - Leave about 5 - 6 inches projecting, you can always shorten the excess. The alignment with the tank fittings is almost exact. Once you have the wings installed and aligned, then determine the finished length approximate length, shove a little excess back into the cabin and make the flares. Pull out the excess and attach to the tanks.
Fuel tank wiring - You will need to make a skin penetration in front of the spar to run these wires to the tank, regardless of what sort of gauge you plan to use.
Front top skin access panels - As I didn't install the canopy release mechanism since I consider access panels more useful overall.
I doub't much of this matters to experienced builders. But if you're a first time builder, as I am. Blindly following the plans can occasionally lead you astray and the further along you are the more vague the plans become until, like a track in the dessert, they disappear entirely.
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| The "cover your butt" section |
This website was built to document my work on my RV-9A in
compliance with the FAA requirements needed to certify my aircraft. My experiences and comments are by
no means to be considered as instructions on how to build an RV-9A or any other aircraft.
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