Standard Practices Airframe; Type Of Bolts - Extra 300LT Maintenance Manual

MAINTENANCE MANUAL EXTRA 300LT
20-10-00
20-10-01
PAGE DATE: 7. July 2010

STANDARD PRACTICES AIRFRAME

Type of Bolts

For the Extra 300LT, LN-bolts (LN="Luftfahrt Norm"), AN-
bolts (AN="Army/Navy") and DIN-bolts (DIN="Deutsche
Industrie Norm") are used. The type of bolt can be identified
by the designation on the bolt head and by the surface
treatment.
LN-Bolts
Hex head LN 9037, LN 9038 K and LN 9355 aircraft bolts
are made of high-strength type 1.7220.5 alloy steel. The
bolts are centerless ground, threaded after heat treatment
and cadmium plated per specification LN 9368-3000.2.
Bolts according LN 9037 are standard aircraft bolts with
undrilled shank. The specification LN 9355 indicates bolts
with shanks drilled for cotter pins. The specification LN
9038 K indicates bolts with drilled head for safety wire and
a shank up to the head.
The added numbers after the dash of bolt spec. indicates the
dimensions of the bolt. These numbers are not marked on the
head of the LN bolt. Measure the diameter and length to
specify the type dimension of the LN bolt. The length of a LN
aircraft bolt is measured from under the head to the end of
the shank.
Example: LN 9037-08042
Bolt Head Identification
Bolt Head:
Letter (R,L,P,H = Identification of
Manufacturer)
LN Specification
Metric thread size
(08 = M8 = 8 mm/0.31 inch)
and Length
(042 = 42 mm/1.65 inch)
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