ENSTROM F-28F/280F SERIES MAINTENANCE
MANUAL
Rev.
7
MM-9-14
Aug
22/16
Table 9-1. Main Rotor Hub Assem
bl
y
– Inspe
ction
P/N Fig.
#
Item #
Part Name
Inspection*
Serviceable Limi
ts*
Repair Limit
s
Repair or Action
28-1
423
5
Fig. 9-3
Item 24
Space
r
Ends pa
rall
el
.0015 FIM
Not repairabl
e
Repl
ace Spacer
28-1
423
3-2
Fig. 9-4
Item 3
Flapping Pin
Thre
ad
s (cro
ssed or
missi
ng
)
Damper bolt hole Di
a.
.5005 to .5015
O.D. 1.7486 t
o
1.7492
Longitudinal scores
or
scrat
c
he
s
Radi
al Sco
re
s
Non
e Allowe
d
+.001
5
-.0005
.011 dee
p
Non
e Allowe
d
Not Repairabl
e
Not Repairabl
e
Not Repairabl
e
.011 deep
Not Repairabl
e
Repl
ace Pin
Repl
ace Pin
Repl
ace Pin
Blend and p
ol
ish out
smooth
Repl
ace Pin
28-1
423
3-3
Fig. 9-4
Item 3
Flapping Pin
O.D. 1.7488 t
o
1.7494
-.0005
Not Repairabl
e
Repl
ace Pin
Inspect the remainder of the flapping pi
n following the
in
spection crit
e
ria listed for
the -2 flapping pin.
* All dimensions are in inches for all t
ables.
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