Wing detachment

[Zoller]

Dear fellow Maulers,
I recently had a bad landing in the Austrian Alps and my left oleo strut snapped during roll out. It was actually a good landing, since I walked away from it. Unfortunately the Maule is damaged on undercarriage wing and prop. For several reasons I need to get it off the mountain ASAP. I was not successful in finding an A&P or even a mechanic to join me in recovering the plane.
Can any of the experts here give me some details on how to detach the wings the best way? Are there pitfalls to consider? Is there a certain sequence of removing parts etc. ? We will have a forklift on a tractor to help suspending the wings.
I will be thankful for each and any information.

Thanks
Peter
MX-7-235

[Old Piper]

Hi Peter / Zoller,

Glad to hear you're alright, planes are replaceable.

My suggestion to your plight is as follows:

Disconnect your battery
Drain Fuel, siphon wing tanks, then drain the 5/7 drain points.
Remove wing fairings, (trail edge has hole at end that allows a flat head screwdriver to enter, CCW to loosen clamp), remove Wing Strut fairings, top and bottom.
Pull headliner away from wing root, access and disconnect wiring connections (Antennas, lights, strobes, pitot tube heater, Ext. Fuel Pump, Fuel Sender connections)
Disconnect Fuel lines (2-per wing)
Cables - Flap cable disconnect in inspection hole closest to fuselage. Alerion is in Headliner zipper above seat backs of Pilot/copilot seats. Also need to loosen or disconnect the block leads as cable exits fuselage on each side.
Bring 5 ea. of 3/16" x 5" lg. bolts or nails, smaller dia. then bolts (Temp. pins) & a long small dia. punch.
Use Temp. Pins to replace wing connect points (Wing Root, Upper & Lower Struts)
While holding end of wing, replace bolts above, adjusting wing loose to allow pins to come out easily.
Have an area ready for standing up wing on leading edge if possible. Care not to damage speed sensor. (laying down may damage pitot tube and wing tips on bottom, or wing antennas on top.)
With one or more holding end of wing, pull Temp. Pins on Wing Struts, then with one person on forward and aft. of wing root, remove wing root Temp. Pins.
Pete, Repeat! for other wing. (Had to do it, don't get that chance to often!)

As for fuselage, suggestion would be to use bucket on tractor to sling fuselage, backing tractor down as practical:

Remove Top Cowling
You didn't mention if taildragger or backwards third wheel mount.
Remove Prop if possible, may not be needed if can keep out of way.
Use bucket to strap a sling to rear point of engine mounts, with possible sling to engine hook to take some weight.
Person on tail to lift guide down mountain. (Remove tail feathers off, elevators/stabilizers, if needed. Bring rubber hammer to ease removal of stabilizers, along with oil spray for forward tube of stabilizer.) Also bring rope/straps to attach left elevator to fuselage, so don't have to cut trim cables/wires.

All doable, take your time to retain all parts as proceeding (put fairings, hdw. in fuselage.)
I've may have missed something, others can chime in to add to this.
Good luck, rebuild and get back in the air quickly.

Tom

[Andy Young]

Tom’s advice is good, except that your MX-7 has a different flap system than he describes (torque tube vs. cables). The traditional way to deal with these is to remove the flap actuator rod from the flap and the torque tube, and remove the saddle bearing in the wing near where the actuator rod is attached. Then, when removing the wing, carefully slide the wing off the fuselage sideways until clear of the torque tube.

I find it much easier to unbolt the torque tube from its other half (and the sprocket) and slide it into the wing (after removing the actuator rod and saddle bearing). Access for this is via the headliner zippers at mid-cabin. This allows you to then drop the wing more or les straight down, without having to work it past the torque tube.

[Old Piper]

Good catch Andy,

I’m use to the M5 old system. I missed the model under Pete’s name.

Curious Pete, how many feet/miles and hills do you have to travel to get to a field/road? Would it be possible to get a jeep and fab. a rack to set on top for the travel, each wing, then fuselage? Or a pickup?

If you have a way to carry them out other than in the fuselage, an easy removal of all seats and battery may lessen the stress during the travel. Any wt. removal is good.

Tom

[Zoller]

You guys are awesome. Thank you so much. I really appreciate that.
Tom, we will have many a hill to climb on the nine hour trip to the landing site. Thankfully, it is accessible by road. This is also part of the problem.the site is a viewpoint, so a crippled aircraft creates a lot of unwanted attraction to tourists passing by, instagrammers, haters and so forth. Mind you this is Europe.
Wednesday a friend who owns an old wrecker and a big trailer will join us and we hopefully will get the bird out without further damage. Altitude is only 3k ft but weather is definitely a factor.

[asa]

Tom’s advice is good, except that your MX-7 has a different flap system than he describes (torque tube vs. cables). The traditional way to deal with these is to remove the flap actuator rod from the flap and the torque tube, and remove the saddle bearing in the wing near where the actuator rod is attached. Then, when removing the wing, carefully slide the wing off the fuselage sideways until clear of the torque tube.

I find it much easier to unbolt the torque tube from its other half (and the sprocket) and slide it into the wing (after removing the actuator rod and saddle bearing). Access for this is via the headliner zippers at mid-cabin. This allows you to then drop the wing more or les straight down, without having to work it past the torque tube.

Like Andy, I would not leave the flap torque tube sticking out of fuselage. Unlike Andy though, I slid mine inboard into the fuselage. I couldn’t get the round sprocket flange through the fuselage triangle into the wings, likely because every maule is a little different. This can be done well before pulling any wing bolts or anything so you can take your time and do what you find easiest.

[Zoller]

Quick update:
It took 2 guys the best part of last week to drive to Austria, dismantle the Maule, load it into trailers and drive it back home to Germany . All this mostly in really nasty Cat III weather conditions.
Your descriptions were extremely helpful for detaching everything in the right sequence.

2 remarks for future reference:
I had the same problem like ASA described. Flanges of the torque tube did not pass through the fuselage web. Had to slide them inboard. I did not remove the fabric headliner, therefore I was not able to slide the tubes completely inboard. They're stick out about 10" each side.

Our trailer was a closed box. Great for weather protection, but it was a hair too short. We had to remove the Rudder. This turned out to be the same problem as the left elevator. The cables of the notorious "aileron/rudder connection" are routed through the fabric in a way they can't be removed without destroying something.
We ended up taping the rudder in an awkward 90 degree angle to the fuselage.

Thank y'all again for the precious help

[Old Piper]

Great News Peter!

I’m glad it was a success! When you get a chance, a few pics of what you were up against would be nice. Here in the US don’t have the opportunity to see that side of the world.

Any other major damage?

Tom

[Zoller]

Thank you Tom,

As I wrote before, the weather was so nasty, there was not much one could take a picture from.

However, there is a nice YT vid about the same location from the 2021 meeting:

https://www.youtube.com/watch?v=wwpNvTe0KO4


here just a few pics on her being a magazine cover girl in '23 and now clipped of her wings in the fog and snow.

The landscape is about the same











As of damage: left wing tip and outer spar. Engine and prop might need shock load inspection.

Peter

[Old Piper]

Hi Peter,

Cool that you got printed on cover page. Looks great!

Looks like you picked the right day to exit the mountain, under cover of Mother Nature.

As for the plane, time, money & patients and parts, it’s rebuildable. Hopefully you have a buddy to get back up in the air during rebuild.

Glad the removal went well.

Tom