# Textron Aviation Service Letter SEL-57-07: No revision named

- Rights: © Textron Aviation Inc. Filed by the FAA in regulations.gov docket FAA-2020-1078, the docket of AD 2023-02-17. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Textron Aviation Service Letter SEL-57-07](https://openairdocs.org/service-documents/cessna/sel57-07.md)
- Title as filed: Textron Aviation Mandatory Safety Letter SEL-57-07
- Pages: 14
- PDF: https://openairdocs.org/files/sha256/f7/6f/f76f4c3b1f1e5f1c0483e83b1e37f9841a15352b2c6cd4a255a54773f724b850
- Page: https://openairdocs.org/service-documents/cessna/sel57-07/file/f76f4c3b1f1e

## Text

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### Page 1

Single
Engine
SER
VICE
LETTER
MANDA
T
OR
Y
SEL
-
57
-
07
TITLE
WINGS
-
MODEL
177
CARR
Y
-
THRU
SP
AR
ONE
-
TIME
EDDY
CURRENT
INSPECTION
EFFECTIVITY
MODEL
SERIAL
NUMBERS
177
17700001
thru
17701
164
177A
17701
165
thru
17701370
177B
17701371
thru
17702752
177RG
177RG0001
thru
177RG1366
F177RG
F177RG0001
thru
F177RG0177
REASON
The
carry
-
thru
spar
can
develop
corrosion
and
cracks.
Corrosion
can
propagate
and
lead
to
crack
development.
A
crack
in
the
carry
-
thru
spar
can
develop
to
a
point
that
the
carry
-
thru
spar
can
have
structural
failure
that
can
result
in
subsequent
loss
of
airplane
control
and
/
or
wing
separation.
Non
-
compliance
with
this
service
letter
may
result
in
undetected
crack(s)
in
the
carry
-
thru
spar
,
which
can
result
in
structural
failure
of
the
carry
-
thru
spar
.
DESCRIPTION
This
service
document
provides
instructions
to
do
a
detailed
visual
inspection
and
an
eddy
current
inspection
of
the
lower
surface
of
the
carry
-
thru
spar
.
COMPLIANCE
W
ARNING:
The
Carry
-
Thru
spar
inspection
presented
in
this
service
letter
applies
to
airplanes
listed
in
the
Effectivity
Section.
The
compliance
time
is
for
unmodified
airplanes
,
and
represents
the
maximum
allowable
time.
Airplanes
that
have
been
modified
to
alter
the
airplane
design
,
gross
weight
,
or
airplane
performance
,
may
need
to
inspect
sooner
.
Examples
of
common
supplemental
type
certificates
(STC’
s)
include
vortex
generators
,
wing
cuffs
,
ST
OL
kits
,
wing
tips
,
and
add
-
on
wing
fuel
tanks.
Contact
the
STC
holder
for
revised
inspection
intervals.
MANDA
T
OR
Y
.
This
service
document
must
be
accomplished
within
10
flight
hours
from
date
of
receipt
as
follows:
NOTE:
Refer
to
the
applicable
service
and
maintenance
manual
,
Section
2A
-
10
-
00
,
Inspection
T
ime
Limits
-
Structure
for
a
description
of
SEVERE
and
TYPICAL
usage
environment
to
determine
the
correct
usage
criteria
for
the
airplane.
If
the
history
of
the
airplane
operation
is
unknown
,
use
the
SEVERE
usage
as
a
determination
for
flight
hours
compliance.
•
For
airplanes
flown
in
SEVERE
Usage
as
defined
in
Section
2A
-
10
-
00:
•
Airplanes
that
have
more
than
2
,
500
flight
hours
must
accomplish
this
document
within
10
flight
hours.
•
Airplanes
that
have
less
than
2
,
500
flight
hours
must
accomplish
this
document
within
10
flight
hours
upon
reaching
2
,
500
flight
hours.
•
It
is
acceptable
to
accomplish
this
service
document
before
2
,
500
hours
to
align
with
a
scheduled
maintenance
event
or
inspection.
•
For
airplanes
flown
in
TYPICAL
Usage
as
defined
in
Section
2A
-
10
-
00:
SEL
-
57
-
07
June
24
,
2019
Page
1
of
10
T
extron
A
viation
Customer
Service
,
P
.O.
Box
7706
,
Wichita
,
KS
67277
,
U.S.A.
1
-
316
-
517
-
5800
This
document
contains
technical
data
and
is
subject
to
U.S.
export
regulations.
This
information
has
been
exported
from
the
United
States
in
accordance
with
export
administration
regulations.
Diversion
contrary
to
U.S.
law
is
prohibited.
ECCN:
9E991
COPYRIGHT
©
2019

### Page 2

SEL
-
57
-
07
Page
2
June
24
,
2019
Single
Engine
SER
VICE
LETTER
MANDA
T
OR
Y
SEL
-
57
-
07
•
Airplanes
that
have
more
than
15
,
000
flight
hours
must
accomplish
this
document
within
10
flight
hours.
•
Airplanes
that
have
less
than
15
,
000
flight
hours
must
accomplish
this
document
within
10
flight
hours
upon
reaching
15
,
000
flight
hours.
•
It
is
acceptable
to
accomplish
this
service
document
before
15
,
000
flight
hours
to
align
with
a
scheduled
maintenance
event
or
inspection.
A
service
document
published
by
T
extron
A
viation
may
be
recorded
as
completed
in
an
aircraft
log
only
when
the
following
requirements
are
satisfied:
1)
The
mechanic
must
complete
all
of
the
instructions
in
the
service
document
,
including
the
intent
therein.
2)
The
mechanic
must
correctly
use
and
install
all
applicable
parts
supplied
with
the
service
document
kit.
Only
with
written
authorization
from
T
extron
A
viation
can
substitute
parts
or
rebuilt
parts
be
used
to
replace
new
parts.
3)
The
mechanic
or
airplane
owner
must
use
the
technical
data
in
the
service
document
only
as
approved
and
published.
4)
The
mechanic
or
airplane
owner
must
apply
the
information
in
the
service
document
only
to
aircraft
serial
numbers
identified
in
the
Effectivity
section
of
the
document.
5)
The
mechanic
or
airplane
owner
must
use
maintenance
practices
that
are
identified
as
acceptable
standard
practices
in
the
aviation
industry
and
governmental
regulations.
No
individual
or
corporate
organization
other
than
T
extron
A
viation
is
authorized
to
make
or
apply
any
changes
to
a
T
extron
A
viation
-
issued
service
document
or
flight
manual
supplement
without
prior
written
consent
from
T
extron
A
viation.
T
extron
A
viation
is
not
responsible
for
the
quality
of
maintenance
performed
to
comply
with
this
document
,
unless
the
maintenance
is
accomplished
at
a
T
extron
A
viation
-
owned
Service
Center
.
CONSUMABLE
MA
TERIAL
Y
ou
must
use
the
consumable
materials
that
follow
,
or
their
equivalent
,
to
complete
this
service
document.

### Page 3

Single
Engine
SER
VICE
LETTER
MANDA
T
OR
Y
SEL
-
57
-
07
NAME
NUMBER
MANUF
ACTURER
USE
Cor
-
Ban
23
COR
-
BAN
-
23
(U074098)
(12oz
aerosol)
T
extron
A
viation
Parts
Distribution
7121
Southwest
Boulevard
Wichita
,
KS
67215
Corrosion
Inhibiting
Compound
coating
Formit
-
18
Fan
Formit
-
18
T
extron
A
viation
Parts
Distribution
Nozzle
for
Cor
-
Ban
23
application
Corrosion
Resistant
Primer
K000574
(2oz
Kit)
T
extron
A
viation
Parts
Distribution
Preferred
corrosion
resistant
epoxy
primer
Color
Chemical
Film
T
reatment
1445846
(Alodine
1
132
T
ouch
n
Prep
Pen)
T
extron
A
viation
Parts
Distribution
T
o
prepare
aluminum
surface
for
intermediate
primer
.
Methyl
Propyl
Ketone
TT
-
I
-
735
Commercially
A
vailable
Cleaning
solvent
for
Corban
Corrosion
Inhibiting
Compound.
Isopropyl
Alcohol
TT
-
I
-
735
Commercially
A
vailable
T
ype
I
Cleaning
Solvent
for
surface
cleaning
prior
to
painting
Aluminum
oxide
paper
or
cloth
(high
purity)
-
180
and
220
or
320
grit
Commercially
A
vailable
T
o
remove
paint
before
inspection
and
surface
preparation
before
painting
Extreme
Simple
Green
Aircraft
and
Precision
Cleaner
Commercially
A
vailable
T
o
be
used
for
cleaning
soiled
surface
CAUTION:
Do
not
use
any
other
Simple
Green
products
other
than
Extreme
Simple
Green
as
some
have
been
found
to
be
corrosive.
NOTE:
T
extron
A
viation
has
also
tested
and
approved
Cor
-
Ban
35
and
ARDROX
A
V
-
8.
These
products
may
be
used
in
place
of
Cor
-
Ban
23
at
the
owners
discretion.
T
OOLING
NAME
NUMBER
MANUF
ACTURER
USE
10X
Magnifying
Lense
Commercially
A
vailable
For
detailed
visual
inspection
of
carry
-
thru
spar
.
Eddy
Current
Inspection
Equipment
Nondestructive
Inspection
Methods
and
Requirements
,
Document
2A
-
13
-
01
found
in
Section
2A
Supplemental
Inspection
Documents
in
the
appropriate
Model
Service
or
Maintenance
Manual
For
Eddy
Current
inspection
of
carry
-
thru
spar
lower
surface.
REFERENCES
Cessna
Model
177
(1968
-
1978)
Service
Manual
Cessna
Model
177RG
(1971
-
1975)
Maintenance
Manual
Cessna
Model
177RG
Series
(1976
-
1978)
Service
Manual
Inspection
T
ime
Limits
-
Structure
,
Section
2A
-
10
-
00
found
in
Section
2A
Supplemental
Inspection
Documents
in
the
appropriate
Model
Service
or
Maintenance
Manual
,
SEL
-
57
-
07
June
24
,
2019
Page
3

### Page 4

SEL
-
57
-
07
Page
4
June
24
,
2019
Single
Engine
SER
VICE
LETTER
MANDA
T
OR
Y
SEL
-
57
-
07
Nondestructive
Inspection
Methods
and
Requirements
,
Document
2A
-
13
-
01
found
in
Section
2A
Supplemental
Inspection
Documents
in
the
appropriate
Model
Service
or
Maintenance
Manual
NOTE:
T
o
make
sure
all
publications
used
are
complete
and
current.
Refer
to
www
.txtavsupport.com.
PUBLICA
TIONS
AFFECTED
None
ACCOMPLISHMENT
INSTRUCTIONS
1.
Prepare
the
airplane
for
maintenance.
A.
Make
sure
that
the
airplane
is
electrically
grounded.
B.
Make
sure
that
all
switches
are
in
the
OFF
/
NORM
position.
C.
Disconnect
electrical
power
from
the
airplane.
(1)
Disconnect
external
electrical
power
.
(2)
Disconnect
the
airplane
battery
.
D.
Attach
maintenance
warning
tags
to
the
battery
and
external
power
receptacle
that
have
"DO
NOT
CONNECT
ELECTRICAL
POWER
-
MAINTENANCE
IN
PROGRESS"
written
on
them.
2.
Remove
the
pilot
and
co
-
pilot
seats.
(Refer
to
the
applicable
Model
Service
or
Maintenance
Manual.)
3.
Get
access
to
the
lower
surface
of
the
carry
-
thru
spar
by
removing
upholstery
,
headliner
,
and
installed
utility
or
oxygen
systems
as
necessary
.
(Refer
to
the
applicable
Model
Service
or
Maintenance
Manual.)
4.
If
installed
,
Remove
foam
from
bottom
of
carry
-
thru
spar
as
applicable.
A.
Clean
all
adhesive
residue
from
the
carry
-
thru
spar
.
5.
Clean
the
lower
surface
of
the
carry
-
thru
spar
of
grime
or
debris.
6.
(Refer
to
Figure
1
,
Sheets
1
-
3.)
Use
a
10X
magnification
lens
to
do
a
detailed
visual
inspection
of
the
carry
-
thru
spar
for
corrosion
with
particular
attention
to
the
locations
as
follows:
•
Where
support
wires
in
the
air
duct
contact
the
structure.
•
Where
upholstery
pads
contact
the
spar
.
NOTE:
A
detailed
visual
inspection
is
described
as
an
intensive
visual
examination
of
a
specific
structural
area
,
system
,
installation
,
or
assembly
to
detect
damage
,
failure
,
or
irregularity
.
A
vailable
lighting
is
normally
supplemented
with
a
direct
source
of
good
lighting
at
an
intensity
deemed
appropriate
by
the
inspector
.
Inspection
aids
such
as
mirrors
,
magnifying
lenses
,
borescopes
etc.
may
be
used.
Surface
cleaning
and
elaborate
access
procedures
such
as
panel
or
component
removal
,
may
be
necessary
.
A.
If
corrosion
is
found
on
the
carry
-
thru
spar
,
the
area
can
be
reworked
as
follows:
(1)
Use
180
grit
or
finer
aluminum
oxide
abrasive
paper
,
cloth
or
pads
to
carefully
remove
corrosion
and
blend
that
area
locally
around
the
af
fected
region.
(2)
Make
sure
to
only
remove
the
minimum
material
necessary
to
blend
the
corroded
surface
with
the
surrounding
surface.
(3)
Maintain
a
minimum
of
20:1
blend
to
depth
ratio.
(4)
Leave
no
sharp
edges
after
blending.
(5)
Finish
with
a
220
grit
or
finer
grained
aluminum
oxide
sandpaper
.
(6)
Use
clean
dry
air
to
blow
of
f
dust.
(7)
Use
a
clean
cloth
wet
with
isopropyl
alcohol
to
clean
the
surface.

### Page 5

Single
Engine
SER
VICE
LETTER
MANDA
T
OR
Y
SEL
-
57
-
07
(8)
Measure
the
blended
area
and
contact
T
extron
A
viation
Structures
with
the
dimension
of
blended
area
for
evaluation.
(Refer
to
the
Carry
-
Thru
Spar
Inspection
Report
for
contact
information.)
(9)
Complete
the
eddy
current
inspection
,
go
to
Step
7.
B.
If
no
corrosion
is
found
on
the
carry
-
thru
spar
,
complete
the
eddy
current
inspection
,
go
to
Step
7.
7.
(Refer
to
Figure
1
,
V
iew
A
-
A.)
Do
an
eddy
current
inspection
of
the
carry
-
thru
spar
as
follows:
(Refer
to
2A
-
13
-
01
,
Nondestructive
Inspection
Methods
and
Requirements
in
the
appropriate
Model
Service
or
Maintenance
Manual.)
A.
Plan
out
the
inspection
process
to
cover
the
items
listed
as
follows:
•
If
the
eddy
current
inspection
is
performed
by
qualified
personnel
that
are
not
representing
an
F
AA
Certified
Repair
Station
,
an
A&P
Mechanic
may
supervise
the
inspection
and
make
the
appropriate
logbook
entry
.
•
T
echnician
must
be
Level
2
certified.
•
Eddy
current
inspection
will
cover
the
lower
service
of
the
carry
-
thru
spar
starting
as
far
outboard
on
either
side
as
reachable
inside
the
fuselage.
•
Eddy
current
inspection
will
be
with
a
0.125
-
inch
probe.
•
T
echnician
should
use
an
inspection
approach
that
ensures
the
entire
surface
is
inspected
without
gaps.
•
One
example
of
a
technique
is
to
inspect
small
equally
spaced
sections
,
no
wider
than
4
inches.
•
Inspect
one
section
at
time
and
overlap
each
section
by
0.25
-
inch.
overlap
between
each
section
and
identify
when
each
section
is
complete.
•
Identify
when
each
section
is
complete
to
help
keep
track
of
progress.
B.
Review
the
General
Requirements
and
Eddy
Current
Inspection
sections
of
2A
-
13
-
01
Nondestructive
Inspection
Methods
and
Requirements.
C.
Calibrate
the
eddy
current
instrument
-
Impedance
Plane.
(Refer
to
2A
-
13
-
01
,
Nondestructive
Inspection
Methods
and
Requirements
,
Section
2.
Eddy
Current
Inspection.)
D.
Eddy
current
scan
the
surface
with
an
0.125
-
inch
diameter
surface
pencil
probe
at
200
kHz.
•
Scan
direction
must
be
with
an
inboard
to
outboard
direction.
•
Use
of
a
non
-
metallic
straight
edge
as
a
guide
will
help
ensure
there
is
not
a
fore
-
aft
motion
of
the
probe.
•
Probe
one
small
section
of
only
a
couple
of
inches
at
a
time
,
recommend
no
wider
than
4
-
inches.
•
Move
the
probe
in
0.125
-
inch
increments.
•
Overlap
each
section
by
0.25
-
inch.
•
Use
of
a
slow
controlled
methodical
process
to
make
sure
the
entire
surface
is
covered.
(1)
Start
the
inspection
in
the
center
of
the
carry
-
thru
spar
and
work
from
inboard
to
outboard
in
small
methodically
controlled
sections
with
a
0.25
-
inch
overlap
until
as
far
outboard
as
reachable
inside
the
fuselage
then
repeat
the
process
for
the
other
half
of
the
carry
-
thru
spar
.
(2)
Look
for
a
sharp
response
of
10
-
percent
screen
height
or
more
may
indicate
corrosion
or
fatigue
cracking
or
both.
E.
If
you
find
one
or
more
cracks
,
further
flight
is
NOT
permitted.
Y
ou
must
replace
the
carry
-
thru
spar
before
further
flight.
F
.
Provide
the
results
of
the
detailed
visual
and
eddy
current
inspections
to
T
extron
A
viation
,
Structural
Repair
.
Use
the
Carry
-
Thru
Spar
Inspection
Report
form
and
pictures
as
applicable.
T
elephone
number
and
email
address
are
provided
on
the
form.
NOTE:
The
Carry
-
Thru
Spar
Inspection
Report
form
must
be
sent
to
T
extron
A
viation
,
Structural
Repair
to
report
all
conditions
,
cracks
,
corrosion
,
or
no
cracks
or
no
corrosion.
8.
If
there
has
been
rework
,
apply
Color
Chemical
Film
T
reatment
to
the
bare
aluminum
surface.
9.
If
there
has
been
rework
,
apply
Corrosion
Resistant
Epoxy
Primer
to
all
bare
metal.
SEL
-
57
-
07
June
24
,
2019
Page
5

### Page 6

SEL
-
57
-
07
Page
6
June
24
,
2019
Single
Engine
SER
VICE
LETTER
MANDA
T
OR
Y
SEL
-
57
-
07
10.
Apply
Corrosion
Inhibiting
Compound
(CIC)
to
the
entire
lower
surface
of
the
carry
-
thru
spar
that
is
accessible
in
the
fuselage
as
follows:
(Refer
to
SEL
-
51
-
01
Standard
Practices
-
Structures
-
Use
of
Corrosion
Inhibiting
Compounds.)
NOTE:
SEL
-
51
-
01
is
a
resource
that
provides
additional
detailed
information
about
the
application
process
of
CIC
such
as
equipment
,
facility
,
cleaning
,
masking
,
and
application
processes.
A.
Mask
areas
around
the
carry
-
thru
spar
areas
to
prevent
over
spray
of
the
CIC.
B.
Spray
aerosol
with
extension
tube
to
minimize
over
spray
.
C.
Apply
the
CIC
in
one
full
wet
coat.
D.
Apply
CIC
to
the
full
lower
surfaces
of
the
carry
-
thru
spar
.
E.
Some
sag
/
run
is
acceptable.
A
spot
of
significant
sag
/
run
needs
to
be
cleaned
by
MPK
(methyl
propyl
ketone)
wiping
and
the
CIC
shall
be
reapplied.
F
.
W
et
film
thickness
of
CIC
is
approximately
1
to
2
mils
for
Cor
-
Ban
23.
NOTE:
The
coating
should
be
tack
-
free
after
two
to
three
hours.
G.
After
the
CIC
coating
is
tack
-
free
,
remove
the
masking
from
around
the
application
area.
H.
Let
the
CIC
coating
cure
with
a
minimum
cure
temperature
no
less
than
50
degrees
F
.
1
1.
Install
removed
utility
systems
,
oxygen
systems
,
headliner
and
upholstery
that
was
removed
to
access
the
carry
-
thru
spar
.
(Refer
to
the
applicable
Model
Service
or
Maintenance
Manual.)
12.
Install
the
pilot
and
co
-
pilot
seats.
(Refer
to
the
applicable
Model
Service
or
Maintenance
Manual.)
13.
Remove
the
maintenance
warning
tags
and
connect
the
airplane
battery
.
14.
Make
an
entry
in
the
airplane
logbook
that
states
compliance
and
method
of
compliance
with
this
service
document.

### Page 7 (OCR)

Single  Beechcraft  Hawker
Engine  SERVICE LETTER  Cessna
TEXTRON AVIATION
MANDATORY  SEL-57-07
B21854
Carry-Thru
Spar
Wing
Attachment Lug
DETAIL A
0510T1035
A1210X1037
Figure 1. Carry-Thru Spar Inspection (Sheet 1)
SEL-57-07
June 24, 2019  Page 7

### Page 8 (OCR)

Engine  Single  SERVICE LETTER  Beechcraft  Cessna  Hawker
TEXTRON AVIATION
MANDATORY  SEL-57-07
B21855
Area to Inspect
Eddy Current Pencil Probe
VIEW A-A
View Looking Up at Lower Surface of the Carry-Thru
NOTE: Eddy Current Pencil Probe motion of travel is center to outboard
while working small equally spaced overlapping sections.
Illustration shows equally spaced sections as an example.
The Eddy Current Inspection will cover the entire lower surtace
of the carry-thru spar that is accessible inside the fuselage.
2110068-1
Figure 1. Carry-Thru Spar Inspection (Sheet 2)
SEL-57-07
Page 8  June 24, 2019

### Page 9 (OCR)

Single  Beechcraft  flawker
Engine  SERVICE LETTER  Cessna
TEXTRON AVIATION
MANDATORY  SEL-57-07
B21856
0.064 Inch
2.5 mm
Corrosion on Lower Surface of Carry-Thru Spar
NOTE: Image not to scale.
Figure 1. Carry-Thru Spar Inspection (Sheet 3)
SEL-57-07
June 24, 2019  Page 9

### Page 10

SEL
-
57
-
07
Page
10
June
24
,
2019
Single
Engine
SER
VICE
LETTER
MANDA
T
OR
Y
SEL
-
57
-
07
MA
TERIAL
INFORMA
TION
No
parts
are
required
to
complete
this
service
document.

### Page 11

Single
Engine
A
TT
ACHMENT
MANDA
T
OR
Y
SEL
-
57
-
07
CARR
Y
-
THRU
SP
AR
INSPECTION
REPORT
T
o:
Page:
1
of
___
Pages
Wichita
Citation
Service
Center
Includes
this
cover
sheet
Attn:
T
eam
Structures
2121
S.
Hoover
Rd
Wichita
,
Kansas
67209
Phone
Number:
316
-
517
-
6061
email:
csstructures@txtav
.com
From:
Registration
No.:
Date:
T
otal
T
ime
in
Service
(Hrs.):
Airplane
Serial
Number:
Owner's
Name:
Facility
Name:
Owner's
Address:
Facility
Address:
Owner's
Phone
Number:
Phone
Number
of
Facility:
Owner's
Fax
Number:
Fax
Number
of
Facility:
Please
provide
detailed
and
dimensioned
descriptions
of
any
crack(s)
or
corrosion.
Attach
pictures
to
this
form
as
necessary
.
Comments
/
Notes:
Cracks:
Y
es
No
(Circle
One)
Corrosion:
Y
es
No
(Circle
One)
Airplane
Operation:
Severe
Y
es
No
(Circle
One)
T
ypical
Y
es
No
(Circle
One)
Unknown
Y
es
No
(Circle
One)

### Page 12

(No text on this page.)

### Page 13

Single
Engine
OWNER
ADVISOR
Y
SEL
-
57
-
07
TITLE
WINGS
-
MODEL
177
CARR
Y
-
THRU
SP
AR
ONE
-
TIME
EDDY
CURRENT
INSPECTION
T
O:
Cessna
Model
177
Aircraft
Owner
REASON
The
carry
-
thru
spar
can
develop
corrosion
and
cracks.
Corrosion
can
propagate
and
lead
to
crack
development.
A
crack
in
the
carry
-
thru
spar
can
develop
to
a
point
that
the
carry
-
thru
spar
can
have
structural
failure
that
can
result
in
subsequent
loss
of
airplane
control
and
/
or
wing
separation.
Non
-
compliance
with
this
service
letter
may
result
in
undetected
crack(s)
in
the
carry
-
thru
spar
,
which
can
result
in
structural
failure
of
the
carry
-
thru
spar
.
COMPLIANCE
W
ARNING:
The
Carry
-
Thru
spar
inspection
presented
in
this
service
letter
applies
to
airplanes
listed
in
the
Effectivity
Section.
The
compliance
time
is
for
unmodified
airplanes
,
and
represents
the
maximum
allowable
time.
Airplanes
that
have
been
modified
to
alter
the
airplane
design
,
gross
weight
,
or
airplane
performance
,
may
need
to
inspect
sooner
.
Examples
of
common
supplemental
type
certificates
(STC’
s)
include
vortex
generators
,
wing
cuffs
,
ST
OL
kits
,
wing
tips
,
and
add
-
on
wing
fuel
tanks.
Contact
the
STC
holder
for
revised
inspection
intervals.
MANDA
T
OR
Y
.
This
service
document
must
be
accomplished
within
10
flight
hours
from
date
of
receipt
as
follows:
NOTE:
Refer
to
the
applicable
service
and
maintenance
manual
,
Section
2A
-
10
-
00
,
Inspection
T
ime
Limits
-
Structure
for
a
description
of
SEVERE
and
TYPICAL
usage
environment
to
determine
the
correct
usage
criteria
for
the
airplane.
If
the
history
of
the
airplane
operation
is
unknown
,
use
the
SEVERE
usage
as
a
determination
for
flight
hours
compliance.
•
For
airplanes
flown
in
SEVERE
Usage
as
defined
in
Section
2A
-
10
-
00:
•
Airplanes
that
have
more
than
2
,
500
flight
hours
must
accomplish
this
document
within
10
flight
hours.
•
Airplanes
that
have
less
than
2
,
500
flight
hours
must
accomplish
this
document
within
10
flight
hours
upon
reaching
2
,
500
flight
hours.
•
It
is
acceptable
to
accomplish
this
service
document
before
2
,
500
hours
to
align
with
a
scheduled
maintenance
event
or
inspection.
•
For
airplanes
flown
in
TYPICAL
Usage
as
defined
in
Section
2A
-
10
-
00:
•
Airplanes
that
have
more
than
15
,
000
flight
hours
must
accomplish
this
document
within
10
flight
hours.
•
Airplanes
that
have
less
than
15
,
000
flight
hours
must
accomplish
this
document
within
10
flight
hours
upon
reaching
15
,
000
flight
hours.
•
It
is
acceptable
to
accomplish
this
service
document
before
15
,
000
flight
hours
to
align
with
a
scheduled
maintenance
event
or
inspection.
SEL
-
57
-
07
June
24
,
2019
Page
1
of
2
T
extron
A
viation
Customer
Service
,
P
.O.
Box
7706
,
Wichita
,
KS
67277
,
U.S.A.
1
-
316
-
517
-
5800
This
document
contains
technical
data
and
is
subject
to
U.S.
export
regulations.
This
information
has
been
exported
from
the
United
States
in
accordance
with
export
administration
regulations.
Diversion
contrary
to
U.S.
law
is
prohibited.
ECCN:
9E991
COPYRIGHT
©
2019

### Page 14

SEL
-
57
-
07
Page
2
June
24
,
2019
Single
Engine
OWNER
ADVISOR
Y
SEL
-
57
-
07
LABOR
HOURS
For
planning
purposes
only:
WORK
PHASE
LABOR
-
HOURS
Inspection
As
Necessary
MA
TERIAL
A
V
AILABILITY
No
part
are
required
to
complete
this
service
document.
W
ARRANTY
None
NOTE:
As
a
convenience
,
service
documents
are
now
available
online
to
all
our
customers
through
a
simple
,
free
-
of
-
charge
registration
process.
If
you
would
like
to
sign
up
,
please
visit
the
Customer
Access
link
at
www
.txtavsupport.com
to
register
.

---
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