Disassembly: Difference between revisions

A request on the GG for information on how to remove your plane from a non-airport landing site by disassembling it enough to fit it on a trailer or flat bed wrecker lead to this article and the check lists below.

Removing the wings (4 place)

1. Buy a bunch of Zip-Locks bags and a Sharpie to keep track of all your hardware as you remove it.
2. Remove the wing tips.
3. If you're going to be transporting the wings flat, remove the pitot tube and tie-down rings.
4. Remove the aileron to control horn bolt at the center of the fuselage under the back seat (two separate through-bolts on the 4-place).
5. Remove the bolts on the outer aileron bearing bracket and aft spar. Hold up the outer aileron to keep it from falling.
6. Slide aileron assembly with counterweight and bearing bracket out. May have to rotate it slowly to break the friction on the inner control horn; go slowly.
7. Lower flaps to access to the nut on the flap drive arm; remove nut and washer. Alternate method: leave arm attached and move flaps up and down as need to get access to the bolts in the following step. Your goal is to get access to the flap drive clamp bolts, an aluminum block that fits around the large torque tube, in the outboard corners of the "hell hole" under the back seat.
8. Back off (do not remove) the two "set" bolts on each flap drive torque tube clamp and loosen the pinch bolt at the inboard end of the tube. The 2 bolts that pin the clamp to the torque tube need only be backed out 3-4 turns, and will sometimes take the threads out with them if backed completely out. As per the above instruction, you may need to move the flaps up and down a couple times to get access to all the bolts. Be patient.
9. Pull the torque tube out of the clamp block and first (inner) bearing bracket on the wing.
10. Remove outer flap/inner aileron bearing bracket (can be a pain to get to the bolt heads. Again, be patient).
11. Slide flap out, some care is needed to break loose the RTV at the inboard end. Repeat flap removal on the opposite side.
12. Remove sump covers from under wing root.
13. Disconnect pitot line on left wing sump area. The (probably clear) plastic hose that couples the two 1/4" aluminum tubes is probably hard, so just cut the plastic line and replace with a new part (it's cheap) later.
14. Disconnect the electrical (pitot, strobes, nav lights, stall warning switch, etc.) in the sump area, both sides. If any wires do not have a connector in that area (for example, if someone added strobes), cuss at your A&P and snip the wire cleanly; you'll add a connector upon re-assembly. If more than one wire needs to be cut, cuss out your A&P some more and clearly mark each wire (colored tape, label maker, etc) so you'll know which is which on re-assembly.
15. Drain the fuel from wing root sumps by removing the drain valve and using a large diameter funnel. 8-10" is about as small as you can use and not lose fuel on the ground due to any breeze and to the run-off from the edges of the sump, since the threaded boss is flush with the surface. Alternate de-fueling option: buy one of those simple "shaker siphons" (example:http://www.boatshowproducts.com/super-siphon-hose) and use that to siphon out the vast majority of the fuel prior to pulling the sump drain. Makes for a lot less mess.
16. Do we need to state the obvious about using extreme care when de-fueling? The stuff is flammable, you know...
17. Before you proceed further, here's a general AN-type fittings note!. You must not allow the bulkhead (or any) fitting in the wing (or lines) to rotate while you loosen the line nuts, so have the appropriate size wrench handy and HOLD that bulkhead nut against the rib and turn only the line nut. Do not rely on using leverage on lines or fittings to loosen these AN nuts, always use backup wrenches. These lines and fittings are not cheap!
18. Loosen the fuel lines AT THE SUMP and remove the small vent line (some vent lines have a rubber connection between the wing and the sump line, some have a hard aluminum line with a flare at both ends).
19. 26-gallon "long range" tanks: there are two round access covers just fore and aft of the sump cover area that give you access to the areas where these fuel lines go (not the ones outboard of the wing root seal; remove these two covers each side. Once removed you'll see two AN fuel line elbows, one each fore and aft, both sides; remove these elbows and the hard lines that go from these elbows to the fuel sump.
20. 19 gallon tanks: DO NOT take the 19 gallon tank inspection panel screws out! The first bay on the standard tanks is WET! You will access these fittings as you are removing the wings; see notes below.
21. Remove the wing panel to center spar bolts (2 each wing, exactly on the fore and aft centerline of the spar). Judicious use of 3/8-drive socket extensions and swivels may be required; six-point sockets are strongly recommended.
22. Position one person at the inboard leading edge, one at the inboard trailing edge and one at the wing tip. The person at the wing tip will lift UP slightly to unbind the wing from the weight pulling down on the socket joint of the wing spar to center section. The two inboard people CAREFULLY rock the wing up and down 1/4"-1/2" at a time - not too much, just a little! - while the person at the tip pulls OUT.
23. 19 gallon tanks: You will need to move the wing out from the wing root only an inch or so, to allow access to the AN fuel line fittings at the inboard rib on the 19-gallon tanks. Once it's out an inch remove this line.
24. 26-gallon "long range" tanks: as long as you removed the fuel lines and elbows as described above, you can remove the wing without removing this lines that go to the tanks. However, take care not ensure you do not damage these extending lines as you are removing the wing, they are coming out of a small hole and can get caught.
25. All airplanes: remember you've got wires and hoses that may extend into the wing through holes in the wing root. Do not rotate the wing so much as to damage these.
26. With fuel lines loose from wing, rock it as before, nose up and down while pulling outboard. The socket joint is just over 1 foot long, so go slow when you get beyond 8-10" away from the wing root. Pull wing panel off and set on a padded surface.
27. Grab your favorite beverage and marvel at what you just accomplished. Then get back to work and get that airplane back in the sky!

There are some differences in removing the 2 place wings. Mostly because of the differences in the fuel system.

Placeholder here to convince some Grumman guru to write up instructions on how to remove the horizontal stabilizers (which you need to do if you're transporting the airplane on public roads on a trailer.)