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Turn the knob on the trim cable so that it is positioned slightly nose down (turned in towards the panel) of the
mid point of its travel.
Thread the WD-415 Trim Cable Anchor Bracket onto the cable.
Thread the jamb nut and clevis onto the end of the cable (thread the clevis on more than 1/2 of its thread
depth). Temporarily connect the clevis to the trim tab horn with the clevis pin.
Position the trim tab in trail to the elevator and adjust the position of the WD-415 Trim Cable Anchor Nut so that
its mounting plate position matches the bottom of the elevator. Cleco the E-816PP Trim Cover Plate in place
using 3/32 clecos. Using the dimension in “Manual Trim Assembly”, DWG 4 as a guide, determine the best po-
sition for the trim cable anchor nut and verify clearance of the cable to the trim cover plate. Readjust the posi-
tion of the clevis and/or the trim cable anchor nut on the trim cable as necessary.
Remove the E-816PP Trim Cover Plate, clevis, jamb nut, and WD-415 Trim Cable Anchor Nut. Clamp the trim
cable anchor nut to the trim cover plate and match-drill #30 through the four 1/8 holes in the trim cable anchor
nut mounting plate.
Reinstall the WD-415 Trim Cable Anchor Nut, jamb nut, clevis and clevis pin as done previously. Cleco the trim
cable anchor nut to the E-816PP Trim Cover Plate. Cleco the trim cover plate to the bottom of the elevator.
Check for the desired travel of the trim tab (see Section 15).
Readjust the position of the clevis and/or the position of the WD-415 Trim Cable Anchor Nut to get the proper
up and down trim tab travel and have more than 50% thread engagement of the clevis to the end of the cable.
Once adjusted, take measurements to allow you too easily return the clevis and the WD-415 Trim Cable Anchor
Nut to the same position on the trim cable.
NOTE: The WD-415 Trim Cable Anchor Nut will not be riveted to the E-816PP Trim Cover Plate until final
assembly of the airplane because it is difficult to thread onto the trim cable with the trim cover plate
attached.
When installing the left elevator during final assembly, use the previously measured dimensions to po-
sition the WD-415 Trim Cable Anchor Nut and clevis on the trim cable as they were before. Rivet the
trim cable anchor nut to the E-816PP Trim Cover Plate.
WING/FUSELAGE ASSEMBLY
During this phase of construction it is necessary to attach the wings to the fuselage to allow for drilling the rear spar/
center section attach, finishing the flap control mechanism, installing the wing tank/fuselage attach brackets, fabri-
cating and fitting fuel & vent lines, and installing the wing root and flap intersection fairings.
Actual installation of the wing panels should be very simple, as the spars have been pre-fitted and drilled for the
center section assembly at the factory. It is helpful to file a slight bevel on the root ends of the spar to assist getting
it started sliding through the slot in the fuselage bulkhead, and to prevent it from scratching and galling the bulkhead
bars as it slides through. Support the inboard ends of the wings when inserting to prevent the bottom of the spar
from dragging along the inside of the fuselage bottom skin. As the wings are pushed in near center, be sure that
the fuselage center bottom skins (which overhangs the fuselage) doesn't catch on the wing skin. When bringing the
spar into its exact position, lining up the bolt holes in the bulkhead and spar, it is often helpful to use drift pins. This
could be a disposable hardware store bolt with the threaded portion removed and the end rounded or tapered on a
grinder. Gently driving this lubricated pin into a nearly aligned hole will center the bulkhead/spar hole so that the
bolts can be installed without excessive force. We recommend that 7/16 hardware store bolts be used for test fitting
to prevent damage to the holes and NAS bolts. When temporarily fitting the wings it is only necessary to install two
7/16 bolts for each wing (one in a top hole and one in a bottom hole). This will minimize the chance for causing any
damage to the holes and allows the choice of holes that will be easiest to tap the bolts back out (particularly on an
RV-8A).
NOTE: Refer to “Section B-B”, DWG 80 for main wing spar hardware callouts when doing the final wing
installation. When installing the wing for the last time, lubricate the NAS bolts with some type of spray lube
(LPS-2 ™, etc.). In lieu of that, a light coat of ordinary motor oil will do. Do not lubricate the threaded por-
tion of the bolt because the torque specifications are for unlubricated threads.
Eleven holes along the inboard edge of the W-804-2-R and W-704-L Wing Lower Inboard Skins (ten of which
are common with the root W-710 Inboard Rib) remain open and are used to secure (with screws) the F-826-1
and F-827-1 Center Bottom Skins (See “Bottom View”, DWG 17A and “Section B-B”, DWG 80). Draw a straight
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line on the wing lower inboard skins from the center of each screw hole towards the wing tip. Make a mark on
each line 3” outboard from the center of the holes. When the wings are attached, and the F-826-1 and F-827-1
Center Bottom Skins cover the screw holes, it will be possible to measure back from the marks and locate the
screw holes on the overlapping center bottom skins.
Rub the spar stub surfaces with Boelube™ or candle wax to help them slide into the center section assembly
more easily.
Use a Unibit™ to drill a hole in the lower fuselage side to allow the pitot line from the left wing to enter the fuse-
lage.
Position the fuselage so that it is level laterally and longitudinally. The wings can be fitted with the fuselage on
the landing gear or other supports as long as it can be leveled. It is helpful to have it high enough off the floor
to allow working under the wings while rigging the flaps and ailerons.
Insert the wings in the fuselage and pin them in place. This is best done with three people; one in the fuselage
to direct movement of the wing for hole alignment, and the other two handling the wing. If the wing spar stub
fits tight in the center section assembly, the person at the outboard end can move it up and down while pushing
to help it slide in.
NOTE: Insert the W-816 Aileron Pushrod Assemblies before attaching the wings to the
fuselage if the wing tips are already attached with blind rivets, or if there is limited space outboard of
the wing tips once the wings are attached.
Recheck that the fuselage is level.
Square the wing to the fuselage. This can be done by measuring the distance from corresponding points on the
wing tips to a common, centerline point on the aft fuselage in a manner similar to that shown in “Wing Align-
ment”, DWG 85. Equate these distances and, at the same time, check that the wings have no forward or aft
sweep. The sweep can be checked by dropping four plumb lines from the wing leading edges (two on each
wing at inboard and outboard points). When they all fall in a straight line, as viewed form the side, there is no
wing sweep. Up to 1/2” forward or aft sweep at the tip is acceptable. The important thing is that both wings have
the same sweep, if any. Mark the inboard/outboard position of the W-807DPP Rear Spar Attach Plate on the F-
806D Rear Spar Attach Bar (See “Section C-C”, DWG 80).
It is time to measure and set the very important wing incidence angle. Take your time and make sure you under-
stand all the concepts and measurements of this critical task, especially the importance of the correct hole place-
ment and edge distance. This is one place where there is only one chance to get it right. If the hole used to join the
rear spar to the fuselage is mis-placed or mis-drilled, the repair can be extremely difficult.
Set the incidence of each wing by using a carpenter’s level and a spacer block as shown in “Setting Wing Inci-
dence”, DWG 85. Rest one end of a level on the wing at the forward face of the front spar web, and the other
end on a spacer placed directly over the web of the rear spar. Shift the rear of the wing up or down to center
the level. The spacer size has been calculated to provide the desired 1/2
q
positive incidence angle. Check
several points along the span of the wing to verify the level reading. Again, it is important that both wings be
the same.
It is extremely important that there is at least 5/8” from fastener center to the edge of the part, in both the
rear spar and F-806 Rear Spar Attach Bars. If unable to maintain proper edge distance, call Van’s Aircraft
for assistance before proceeding further.
Clamp the rear spar in place and locate the center point of the hole (See “Section C-C”, DWG 80). To help drill
square you can tape a small piece of flat aluminum beside the hole location and use the reflection to align the
drill bit. You can also drill a piece of aluminum or steel (about 1/2” thick and about 2” by 2”) on a drill press for a
pilot hole that is square. Clamp this block in place on the rear spar attach. Initially drill an undersize hole starting
with no more than a 3/16 bit. After checking and re-checking the wing fore and aft alignment and incidence an-
gle, enlarge the hole to 5/16 diameter. Drill with a long stiff drill bit or better yet a reamer so the drill motor can
clear the fuselage and make a straight hole.
Use the reference lines and marks on the bottom of the W-804-2-R and W-704-L Wing Lower Inboard Skins to
transfer the screw hole positions to the F-826-1 and F-827-1 Center Bottom Skins. Drill #30 the screw hole loca-
tions in the left and right center bottom skins.
NOTE: Do not final-drill the screw holes at this time.
RV-8 Only:
Make the left and right F-863-1 Tank Attach Brackets (See “F-863-1 Tank Attach Bracket”, DWG
80).
RV-8 Only:
Make the bend adjustments required so the F-863-1 Tank Attach Brackets fit flush with the fuselage
side skins and the T-405 Angles on the fuel tanks as shown in the top view of “Wing/Fuselage Junction”, DWG
80. This can be done by clamping the tank attach bracket in a bench vise with the desired bend line clamped
adjacent to the vice jaws, and then hitting it with a large hammer while protecting it with a wood block.
