MIL-S-6451E
3.4.1 Configuration. Shields for radial engines shall be designed as shown
on figure 1, and shall fit 2 inches into the engine cowl ring when practical.
Shields for the cowl ring of jet aircraft shall be designed as shown on figure
2. The entire opening between the engine and the inlet air duct shall be
closed by the shield.
3.4.1.1 General appearance. The shield shall be so designed as to present
a neat appearance. The shield shall be compact and free of excess materials,
3.4.2 Engine cranking. Shields for radial engines shall be designed to
permit engine cranking with the shields installed in the cowling. Heater
duct attachments, when required, shall not interfere with engine cranking.
The shield shall be designed to assure a minimum service
3.4.3 Service life.
life of 1 year.
3.5 Construction. The shield shall be so constructed that, when assembled,
all protruding parts will be well supported and will not extend beyond the
outer limits of the shield. The shield shall withstand the strains, shock,
vibrations, and other detrimental conditions incident to operation, shipping,
and storage with a minimum loss of time for maintenance, repair, and periodic
servicing.
3.5.1 Class 1 shield. The class 1 shield shall be as shown on figure 1 or
2. The shield shall be constructed of aluminum-alloy sheet conforming to
QQ-A-250/8, 1/2 hard; or QQ-A-250/5, temper O, at least 0.064 inch thick
for shields less than 3 feet in diameter and at least 0.125 inch thick for
shields greater than 3 feet in diameter. The shield for radial engines
shall be-in two sections joined at the horizontal centerline of the engine
propeller shaft. The shield shall fit into the engine cowl or to the cowl
face, and against the propeller hub to form a tight seal. The construction
shall be such that oil-canning will not occur. Provisions shall be made
in a felt seal specified in 3.5.1.3 to allow clearance for the propeller
feathering controls or anti-icing equipment. The shield shall fit 2 inches
inside of the cowl ring and orifice openings when installed inside the
opening.
3.5.1.1 clamps. Clamps shall be substantially as shown on the applicable
figure to secure the shield in place. Where practical, the clamps shall
be located as shown on figures 1 and 2. When the configuration of the
shield will not permit four clamps, a sufficient number of clamps shall be
used to hold the shield in place. Each clamp shall press against the air-
craft skin to hold the shield in place. The force exerted from the clamp
shall not damage the skin. If the aforementioned clamp is not practical,
the clamp shall be designed and constructed to be inserted into the air
duct, or for fastening to the engine cowl.
4
For Parts Inquires submit RFQ to Parts Hangar, Inc.
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business