Learning to fly in the U.S. Army

by E. N. Fales

The system of marking also insures that the struts are not inverted in their sockets. This is accomplished by painting the number on the strut, so that when viewed from the pilot’s seat, all numbers can be read, i.e., the numbers are painted on that side of the strut intended to face the fuselage. If a strut is inverted by mistake, it can thus be quickly detected. The procedure of assembling panels is as follows:

1. The upper left-wing panel is first equipped with mast, by inserting the mast into its socket on the upper surface of the wing. The mast wire is then connected up to the clips to the right and left of the mast. Adjust the tension in this wire, by means of turnbuckles, until the spar becomes straight.

2. Stand the upper left-wing panel and lower left-wing panel on their “leading” or “entering” edges, properly supporting the panels in cushioned blocks to prevent damage to the nose. Space the panels apart, at a distance approximately equal to the length of the struts.

3. Next connect up the diagonal cross wires. These must be loosely connected up, to permit the easy entering of the posts into the sockets. The wires are connected before the posts or struts are set in place, since with the latter in place, the connecting of the wires to the lugs of the sockets is accomplished only with difficulty. After these wires are thus connected, insert the posts and bolts into place.

4. Connect up closely the “landing” (single) wires, and “flying” (double) wires of the outer bay to hold the wings together as a unit. The outer bay is thus completely wired, though but loosely.

5. The posts that are used for this left side are, according to the diagram, No. 1, No. 2, No. 5, No. 6. No. 1 is the outer front; No. 2 is the inner front; No. 5 is the outer rear; No. 6 the inner rear.

6. The wings, as above assembled, are now erected to the fuselage. Extreme care should be exercised in transferring the wings to the fuselage, not to strain or break them. In carrying the wings, use wooden boards placed under the wings, and block up under the wing beams (which can be easily located), so that these take the strain of the load. Do not attempt handling assembled wings, using the posts as carriers; or by attachments to the trailing or leading edges. The wings should be suitably supported temporarily by suitable sling at the outer upper post point (not beyond this point) or by a horse, properly blocked under lower wing at outer lower post point (not beyond this point) during fitting of wing to machine. The wings will have the approximate stagger if assembled as above, since the posts are in place, and the tension cross wires are adjusted to almost correct length when shipped. Insert the hinge pins through the hinges as now coupled up, lower hinges first.

The machine is now ready for alignment, perhaps the most important of the rigger’s duties.

Alignment of Airplanes.—The proper alignment of a machine largely determines the flying qualities of that machine.

The alignment of the fuselage should be done at the factory or in the repair shop. However, the alignment of the whole machine depends upon the correctness of the fuselage. Directions for aligning and checking fuselage are, therefore, given.