holes. The beads stiffen the web portion of the rib.
Rib repair by patching is shown in figure 13-71.
BULKHEADS.Any major vertical structural
member of a semimonocoque fuselage, hull, or float
may be considered a bulkhead. Bulkheads serve to
maintain the required external contour at the station
Figure 13-71.Rib repair by patching.
where they are located. They also give rigidity and
strength to the structure.
Bulkhead construction is similar to that used for
wing ribs. It consists of a web reinforced by angle
stiffeners. The web is attached to the skin by formed
flanges or extruded angles, which serve as capstrips.
Non-watertight bulkheads may have lightening holes,
and most bulkheads are cut out to give clearance for
stringers. The stringers are usually attached to the
bulkhead by angle clips.
The repair of the web and formed flange of a
bulkhead is similar to that used for the rib web and
flange repair shown in figure 13-71; however, the
structural repair manual must be consulted for
specific information on the repair of a particular
When damage to the web is a crack, dent, or small
hole, it may be repaired in the same manner as fully
stressed skin. Buckled webs may be repaired by
riveting an angle reinforcement over the buckled area,
provided the bulkhead is not otherwise distorted.
Sheet metal used for repairs near a flanged lightening
hole should be formed with a 90-degree flange to
provide additional stiffening.
LONGERONS.Most aircraft fuselages are
constructed in sections and are of the semimonocoque
design. A longeron is a fore-and-aft member of the
fuselage or nacelle and is usually continuous across a
number of points of support, such as frames and
bulkheads. The longerons, along with the stringers,
are the major load-carrying members and stiffeners.
Figure 13-72 shows the location of the major
members of a semimonocoque design forward
fuselage. In case it becomes necessary to repair a
longeron, review the section on stringer repair and
follow the same procedure.
RECOMMENDED READING LIST
NOTE: Although the following references were
current when this TRAMAN was published, their
continued currency cannot be assured. Therefore,
you need to be sure that you are studying the latest
Use and Care of Hand Tools and Measuring Tools,
NAVEDTRA 12085, Naval Education and
Training Program Management Support Activity,
Pensacola, Florida, 1992.