Sequoia Aircraft Corporation F.8L Falco, Руководство по монтажу

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F.8L Falco Construction Manual 2–4 Revision 4, March 1, 2002
A view is just like a section, but the part is not cut through. A view is a designer's way of saying
“This is what the part would look like if you looked at it from here”. Figure 3 shows an example
of a view of our little house.
Dimensioning
Take a look at Drawing No. 807. The dimensions for the Falco are given in millimeters unless
otherwise specified. In general, you will find that all dimensions are given in millimeters, except
those that are generically English measure (inches).
If you have never worked with metric dimensions before, you are in for a real surprise. They are
much nicer to work with than with the inches we are all accustomed to. The only problem arises
when something is made in inches. When we want you to drill a 1/4” diameter hole, we just call
out the hole as .250ӯ. This is simple and easy to understand.
While it is not required that you do many conversions of millimeters to inches, you should still
know how. A millimeter is .03937”, so to convert 35mm to inches, you multiply (example: 35mm
x .03937 = 1.378”). To convert from inches to millimeters, you divide by .03937 (example: 4.75”
÷ .03937 = 120.65mm). In most cases you will not be concerned with the exact equivalent, and
for quick and easy conversions you can use .04 as your conversion factor. If you see a material
called out as 3mm, then you can quickly see that it is roughly .120”, so the U.S. equivalent is
.125” (1/8”). You will soon be thinking of 1mm steel as .040” steel, 1.5mm aluminum as .063”,
2mm as .080”, etc.
The plan convention for the Falco (and most other aircraft) is that the dimensions for the spars,
ribs, fuselage frames, etc. are given for the
undersurface of the skin. Thus, you do not have to make
any allowance for the thickness of the skin of the aircraft.
Water Lines, Butt Lines & Stations
A “water line” is a horizontal plane through the airplane. The most important water line is Water
Line 0 , which is the primary horizontal reference plane on the airplane. This is abbreviated as
W.L. 0 and may be seen on the fuselage frame drawings. All vertical dimensions in the fuselage
are taken from W.L. 0. If we wish to indicate a plane 355mm below W.L. 0, we will refer to the
point as W.L. –355. A plane 70mm above W.L. 0 would be referred to as W.L. 70. The normal
practice is not to use a plus sign with water lines above W.L. 0.
A “butt line” is a vertical plane through the airplane. This convention is used to refer to a plane
to the side of the aircraft centerline. The aircraft centerline is effectively B.L. 0, although this is
never used.
The positions of the wing ribs, tail ribs and fuselage frames are referred to as Stations.
General Tolerances
The general tolerances for dimensions is ±0.1mm unless stated otherwise. These tolerances do
not apply to the thickness of specified materials, and you must use the stated millimeter or inch
measure material. When tolerances are important, the actual limits are given since the European
tolerance system is confusing to anyone not accustomed to using the tolerance tables.
Not to Scale
Occasionally, you will find a dimension with a straight or wavy line beneath it. This means “not
to scale”. In all cases the dimensions on the plans take preference to the drawing itself, and you
should not scale directly from the drawing unless you are instructed to do so. In some cases, the