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I've seen this video from Airbus:

This is a capture from that video:

Horizontal stabilizer being lifted with crane

What is the process for attaching the wings to the fuselage?

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The answer of ymb1 already gives you some good answer, but you marked in the comments, that you are also interested in the process of attaching. Therefore I'd like to provide you some more information and did some sketches number I) to III) for the Wing Root (at the end of the section) and another sketch for the horizontal stabilizer installation.

1) Wing Root Joint:

Generally, there are many ways to connect a wing to the fuselage. The most common ones in large commercial aircrafts or military jets are:

I) Spliced Shear Plates: This is exactly what you can see in the video. You will find these joints in many large civil aircrafts because they are lightweight and inherent fail-safe (because it is a continuous joint a single fastener failure is not catastrophic). However, they are a bit more complicated in manufacturing leading to higher costs. Furthermore, it might be not feasible for very thin wings (e.g. wings of super-sonic aircrafts)

The sketch I) shows a section cut along the so-called cruciform fitting which you see in the video. The wing starts left of the root rib, the fuselage (and center wing box) is right of it. The bolts are placed continuously along the joint and they are loaded in shear. Shear loading is generally a good way of loading for the fasteners, leading to a lighter design.

How is it manufactured? Normally the Fuselage and the Center Wing Box are already build together and the wing arrives seperately. In the assembly line, the wing will be moved close to the fuselage so that the wing skin is directly underneath the cruciform fitting. However, it is important to place the wing in the right place. Then you start drilling the hole and connect the wing to the fuselage. There is a german TV show for kids which shows also scientific stuff. Once they provided a full documentation of the assembly of an A320 (Sendung mit der Maus - Flugzeugbau). You might watch this brilliant video to get a good understanding of how it the wing is assembled to the fuselage (even worth it if you do not understand a single word of german):

Now you can also see what I meant with more complicated manufacturing and why it is complicated to use this concept for very thin wings.

Situation in the video

II) Tension Bolts: I tried to show it in sketch II). You see that both - wing (a) to b)) and fuselage (c) to d)) - have so called tension bolt fittings. Those are relatively strong fittings designed to transfer the wing bending moment in the form of tension loads over big bolts from the wing to the fuselage. You will also have multiple or continuous tension bolts along the joint. You can also see that the assembly of them is better suited for thin wings and therefore they are used for many figher aircraft or the Concorde. As stated above, it is better to load the bolts in shear... but here you load them with tension loads. This makes the bolts itselft, but also the surrounding structure heavier.

III) Lug Fittings: You have several fittings with lugs on the wing and the fuselage which are connected with bolts. Normally these lugs are located at the wing spars. Having only few lugs and special areas means that all your load path is concentrated towards these points. This leads to heavy reinforcements around the lugs. Furthermore you need to implement additional design features to make them fail safe.

However it is "easy" (compared to the other concepts) to attached them to the fuselage and to take them off again. Therefore you might find them in aircrafts which you need to transport (military fighter jets, drones, gliders, ...)

Sketches of various wing root joint concepts

2) Horizontal Stabilizer:

The sketch below shows the fuselage with the dedicated cut-out and the horizontal stabilizer itself. Normally the stabilizer is inserted into the cut-out while the fuselage fittings 1) and 2) are removed. Once the stabilizer is in position, its fittings 4) will be connected to the fuselage fitting / pivot 2) which is put in place again. Then the fittings 3) of the stabilizer will be attached to the fitting 1) of the fuselage. This fitting 1) is sitting on a huge jack screw, so that it can move up and down, while the rear hinge line stays in place resulting in an up and down movement of the horizontal stabilizer. Once everything is assembled, the fuselage rear cone is installed at the end of the fuselage. (you might also watch more of this german TV show for kids, they have also an internal view of the moving jack screw :-) )

Sketch of horizontal stabilizer assembly Situation in the video with view of the pivot

I hope that answers your question :-)

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The main wing comes in two pieces, left and right wings, and they are bolted to the lower center fuselage section, which also houses the center fuel tank.

Fuselage/wing fillets (fairings) are added after.

enter image description here

The frame you captured shows the rear wing—the horizontal stabilizer. It is slid in and then bolted, more precisely attached to the mechanism that moves it.

enter image description here

(Same video)

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    $\begingroup$ Possible oversimplification: Big bolts! $\endgroup$ – Notts90 Nov 10 '16 at 11:25
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    $\begingroup$ @Notts90 The wings on a Piper Cherokee/Warrior/Arrow are indeed held on by "18 very airworthy-looking bolts" — the logic scales up well :) $\endgroup$ – voretaq7 Nov 13 '16 at 3:28
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    $\begingroup$ @voretaq7 And if I remember correctly most 100 series, and at least some 200 series, Cessna wings are each attached with two very airworthy looking bolts. $\endgroup$ – J Walters Nov 13 '16 at 16:07
  • $\begingroup$ Really good super glue......... $\endgroup$ – Jon Oct 10 at 20:27
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On lighter aircraft, the wings are sometimes designed to be detachable for ease of transport:

Glider being unloaded form a trailer

To achieve this, the wing spar has a stump at the inboard edge that is inserted into a hole in the either the fuselage or the next inner wing section.

Once inserted, they are locked to the fuselage (and often to the wing on the other side) using large metal pins. You will also often see pins at the leading and trailing edges, which are there to counter the aerodynamic torque on the wing: due to the way physics work, it is easier to counter torque with a small pin at a distance from the main spar than make the spar large enough to carry it by itself.

AS glider wing assembly AS glider wing assembly

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  • $\begingroup$ Great picture of the airfoil too. $\endgroup$ – Robert DiGiovanni Oct 11 at 21:52
  • $\begingroup$ The pins at le leading edge and flap spar also carry the lift forces across the joint. The spar only transfers the bending moment. $\endgroup$ – Peter Kämpf Oct 13 at 18:31
  • $\begingroup$ @PeterKämpf You mean they transfer shear? Otherwise I don't think I follow. In my experience with a similar design the spar was sized to carry both bending and shear, but that was one solution, it might be different on the glider in the pictures. $\endgroup$ – AEhere supports Monica Oct 13 at 18:54
  • $\begingroup$ Yes, and shear only. After all, they are just sticking in corresponding bushings, without any locking mechanism except that provided by the spar bolt. This is a standard design used in all German composite gliders. $\endgroup$ – Peter Kämpf Oct 13 at 19:09
  • $\begingroup$ @PeterKämpf do the LE and TE pins go all the way along the span then? The design in the images does look a bit odd to me; for one I expected the spar to be further forward (near the quarter chord), but your comment does shed some light. $\endgroup$ – AEhere supports Monica Oct 14 at 7:39
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I’m a retired FAA licensed A&P mechanic. The wings on the B727 are held on, in part by so called “bottle pins” if memories serves there are two on each wing roughly the dimensions of old fashioned glass quart milk bottles. I’m only “assuming” there are similarities to how the B737max wings are also held in place. Again I’m assuming that the “pickle fork” structures are an adjunct to another center box fitting such as the B727 bottle pins. Any more current info would be interesting.

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