AMCR Flashcards
(75 cards)
During World War 1 (WW1) and the early 1930s, what was the chosen material for
aircraft construction.
wood
Types of Wood
Solid Wood, Laminated Wood, Plywood
It is made from one solid log cut by quarter sawing for the
reduced chance of warpage. Most commonly use in aircraft wing
spars.
Solid Wood
It is made by gluing together two (2) to three (3) pieces of wood
with the same grain direction. Most used also in aircraft wing
spars and interchangeable with solid wood if it has the same
quality.
Laminated Wood
It is made from three (3) or more thin sheets of wood board
glued and pressed together so that its grain would be at an
angle to the successive layer.
Plywood
Species of Wood
Hardwood and Softwood
Comes from deciduous trees, this is a broad-leaved tree which looses its leaves in the winter
Hardwood
Comes from coniferous trees, an evergreen tree, needle-leaved, cone-bearing tree
Softwoods
Whatever species of wood
used for aircraft construction;
its grain orientation should
always be straight. A limit of
variation 1:15 is permitted,
indicating that the grain must
not have an angle of more
than an inch per 15 inches.
Grain Deviation
Are the part where the
tree branch sprouted from
the trunk. There are different
types of shapes of it
depending on the cut from
the wood e.g. round, oval, or
spiked.
Knots
It is a type of wood
imperfection caused by small
holes in the annual rings of a
tree. Woods with it are only allowed to
be used if they are 14 inches
apart and with a volume of
11/2-inches x 1/8-inch x 1/8-
inch deep.
Pitch Pockets
▪ NEVER a good wood for
aircraft construction and
repair.
▪ Wood taken from a tilted
tree as it grows that lead to
its wood having a denser and
weaker wood structure than
a normal grown tree.
Compression Wood
▪ Usually can be identified by
its irregular and thread-like
line on the grains
▪ Also, NEVER a good wood for
aircraft construction and
repair.
Compression Failure
▪ Most used in aircraft construction
▪ Free from defects
▪ Hight Strength-to-Weight ration
▪ Hight Quality Wood
Spruce
▪ Strength is far better than of spruce
▪ Heavier
▪ Difficult to work than spruce with the tendency of splitting
Douglas Fir
▪ Lighter than Spruce
▪ Equal or superior to Spruce in all properties
▪ Lower hardness and shock resistance to Spruce
Noble Fir
▪ Excellent working and gluing characteristics
▪ Strength is inferior to Spruce
Northern White Pine
▪ Exceptionally light weight
▪ Lacks structural strength
▪ Used as a core material for panels for sandwich-type requiring
light weight and rigidity
Balsa
▪ Heavier than Spruce
▪ Stronger than Spruce
▪ Most used in face sheet production of plywood in aircraft skins
Mahogany
▪ Heavy hardwood
▪ Good shock-resistance properties
▪ Recommended for face plies of plywood used in reinforcement
plates on wing spars and in propeller made from wood.
Birch
is a crack running through or across the annual grain
Check
is a crack or separation in which it can be seen from a
detached two annual rings along its boundaries
Shake
are caused by a decay on the wood usually appearing as
streaks in the grains.
Stains
the stain that uniformly discolored the
annual rings.
Decay
