Page 28 - Aeronca 7A Interactive Service Manual

TAIL SURFACES

Newly designed metal ribs, diagonally assembled for additional strength, are incorporated in all of the tail
surfaces. The fabric is attached to the surfaces by means of PK screws, washers and pinked tape.

RUDDER
The rudder design with the top leading edge protruding over the vertical fin provides a counterbalance
action in the rudder control movements.

The rudder is attached to the vertical stabilizer at two points by the use of bushings welded to the rudder
frame and stabilizer and held in place with flat head clevis pins. A horn welded to the rudder and to which
the rudder cables are attached regulates rudder travel by touching adjustable rudder stops welded to the
lower part of the tail post.

Rudder travel can be adjusted at the rudder stops. Travel limitations are 25° plus 0° minus 2° left, 25° plus
0° minus 2° right.

ELEVATORS
The elevators are attached to the horizontal stabilizers by the same means as described for the rudder.
Elevator travel limitations are 25° plus 0° minus 2° up, 15.5° plus 2° minus 2° down.

Incorporated in the left elevator is the all metal trim tab assembly, attached with a continuous type hinge
bolted to the elevator. The trim tab is operated from the cabin.

Trim tab travel limitations are 20° plus 2° minus 0° up and 34.5° plus 2° minus 0° down.

Compensation for weight variations in loading may be quickly and easily accomplished by the use of the
newly designed tab control adjustment in the cabin above the pilot.

HORIZONTAL STABILIZER
The horizontal stabilizer is designed in two interchangeable sections. Rigidity is accomplished by the use of
2330 steel rod heat treated to an ultimate tensile strength of 95,000 P.S.I. These “wires” are cadmium plated
and care should be observed to preserve this protective finish.

Both upper and lower tail wires are attached to fittings on the stabilizer, fuselage and vertical fin by means
of clevis bolts and can be adjusted by turning the wire on the flat space provided for this purpose. A smooth
jaw wrench should be used, adjusted to fit the wire correctly in order to avoid damage of finish. The clevis
fittings are threaded left and right hand to facilitate adjustment without removing the wires or fittings.
Rigging load is 350 to 450 pounds.

VERTICAL STABILIZER
The vertical stabilizer or fin is an integral part of the fuselage and is shown on the fuselage drawing together
with all fittings. This fin is offset ⅜” to the left to compensate for torque and virtually eliminates the
necessity of a rudder trim tab. NOTE: If at cruising R.P.M. a yawing tendency is noted, it is permissible
to install a permanent trim tab on the trailing edge of the rudder, Part Number 1-2190. This tab must be
attached to the same side as the direction of the yaw.

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