BRANTLY INTERNAT IO NAL INC. SERVICE BULLETIN No
: 11 J SERVICE BULLETIN REVISION:-

P AGE:

1 / 4 SE R V I CE BULLETIN

N o: 111 **REVISION:**

**~** SUBJECT: Outboard Main Rotor

· Bl a d es MODEL

S AFFECTE

D : See b e l ow. TIME OF COMP LI ANCE: See below

. FAA APP RO VAL

: To b e s ubmitt ed to th e FAA for a ppr ova
l Intt ·o du ct ion

Fe bruar y 10, 2011 The Brantly Maintenance Manuals for the B2 s e ri es h e li co pt e rs call out an inspection for th e outboard main rot or blades in sec tion 1.8

.1 Preflight and Daily In s p ect i ons. Listed in these sec ti o n s are c rit e ria for in specti n g t h e blades for cracks and damage. Cracks in aU B2 ser i es main rot o r · blade
s are considere

d unairn

• orth y and are ca u se f o r blad e r e p l ac e m e nt. Se r ·v i ce Letter 110 wa s i ss u ed as a r e minder of these in spectio
n s. This serv

i ce b u ll eti n s up erse d es and ca ncels the sec tion s o f the mainten

a n ce m a nuals m e ntioned above
a s well as Serv

i ce Letter 110

.In addi ti o n , this se nric e bull et in s up ersedes

a ll other se n , ice informati on publi

s h ed f or o u tboa rd main rotor blade in s p ec tion s b efo re t h e approva l d a t e of thi s serv

i ce bulletin for p / n 248-101

, 248-202, and 2 48 -40 4 . The

t ab l e s hown b I e ow s hows eac h s up erse ded and canceled sec tion s a nd d oc uments

. Document Name Revi

s ion Section Status B r ·a ntly 82 and B2A Ma
i nt. Manua

l March 1963 1.8
.1 a,b,c,d,e,f,g,h,

& Fig 2 , Superseded! Ca n ce l ed Pg 6A Rev. S, Mar

. 1965 Brantly B2B Main t. Manual May 15,1991

1 . 8.1 a,b,c,d,e,f,
& F i g 11 , Pg
S up ers eded
/ Ca nc e l e d 4 , Rev

- Brantly Serv

i ce Letter 110

- Oct 3 1 ,20 0 5 All

S up erse ded! Ca n ce l ed It i s s u specte d that so me o utb oar d main ro tor bl ades ha ve been
r e built in the fi e l d. R ebu ildin g ma y onl y be acco mplish

e d b y th e m a nuf ac tur e r a nd i s not r eco mm e nd ed or approved
to p e rf or m in the fie l d. Any o wn e r /o perator that
s u spects that a bl a de ha s b ee n rebuilt or repaired without FAA app r ova
l s hould remove th e blade from se n • ic e and r epo rt it to the FAA through th e S u s pected Unapproved Parts Program (SUP) or throu g h the aviation authority in th e a pplicabl

e country. Re pai rs mad e to outboard main rotor blad es mu st m ee t or excee d th e original

d es i g n stre n gt h of the bl ade a nd r eq uir e FAA
a ppro va l. App li cab ili ty A ppli es to models B-2

, B - 2A, o r B-2B that ha ve main rotor b l ades p / n 248-101

, 248-202, and 248-404 in sta ll ed. Comp lianc e Fo r Outboard Main R oto r Blade

s PIN 248-101 and 248-202

, b efo re furth
e r fli g ht , comply wit h se cti o n s 1 and 2 of thi s se rvice bu ll eti n . Th e reafter at int e n
· a l s n ot to exceed

3 00 flight h o ur s or 5 ca l e nd ar yea r s, whichever occ ur s fir s t co mpl y with section

1 an d at int e n

' a l s n ot to exceed 25 flight h ou r s com pl y w i t h sec ti on 2. A l so co mpl y sect
i on 3 of thi s s e n ,i ce bulletin befor ·e t h e fir s t fli ght of eac h day. For Outboard Main Rotor Blades PIN 248-404 wit h l ess t h an 10 years time in sen

,i ce or 1000 flight hour -s, com ply with sect
i on 3 of thi s service bulletin

b efore

t he fi r ·s t flight of e ach day.BRANTLY INTERNATIONAL INC. SERVICE BULLETIN No: 111 I sERVICE BULLETIN

I REVISION:

- PAGE: 2/ 4 Fm· Outboar ·d Main Rotor· Blades PIN 248-404 with mor e than

1 0 years time in se rvice or 1000 fli ght hour s, before further fli g h t, co mpl y with sect ion I a nd 2 of thi s se r v i ce bulletin. Thereafter
at intervals n ot t o exceed 300 fli g ht hou rs or 5 ca l e nd a r yea r s, whichever occurs fir st co mpl y with sect
i o n 1 a nd a t int e r va l s not to exceed 25 fli ght hour
s comply with sectio n 2. Also comp

l y with sect ion 3 of this service bulletin before the flight of eac h d ay. Co nt act: Serv

i ce Department (scrvice@br·antly.com

) Brantly In ter na tio nal Inc. 621 S . R oya
l Lane;
S uite 100 Co pp e ll , TX 75019

- 3805 USA

Phone 972.829.4600 I C r ack In s p ec ti o n (30 0 Ho ur Inspection) 1.1 R e m ove the o utboard main rotor blad e. C l ea n s urfa ce to b e in spec
t ed. R e m ove any contaminates that mi g ht interfere with the discovery of ex istin g s urf ace indi ca ti ons. In spect th e outboard main rotor blad es for cracks
u s in g th e E dd y Current Procedure ET002 attac h ed wi t h this serv

i ce bulletin. 1. 2 No c r acks or nick s a r e p e rmitt e d. No c r eases, wrinkles

o r bend
s are permitted in th e trailing edge of the blad es. Ve rif y adequate

e dg e di s tanc e between hol es s u c h that no a ddition

a l boles have b ee n added or ext r a rivets u sed to fill sto p drilled hol es in the r oo t fitting. A n y blade that ha s c r acks (es p ec iall y aro und t h e r oo t of t h e bl ade), extra ri vets, or stop drilled
b o l es mu s t be removed from service. If any of t h ese defects arc f o und

, r emove the bl a d e from se rvi ce and r ep l ace with a n a irworth
y p a rt . R eco rd the r es ult s in sectio n 4 o f this serv ice bull eti n. 2 Delamination

In s pections (25 Hour Inspection) 2.I R e mo ve th e outboard main rotor blade. Clean

s urfac e to be in specte d. R e move any contaminates that mi g ht int er f e r e with the di s cover y of ex i st in g s urfac e indications. Use a s uitable light and a JOX m ag nif yi n g g l ass to in s pe c t for
· cracks in the main rotor bl ade. P ay particular· attention to areas amund r iv et h o l es, the blade root ar ea, and th e trailing edge. 2.2 No cr-acks or nicks are permitted. No creases

, wrinkl es or bend
s are per mitt e d in the trai ling edge of the blades. Verif y a d e qu ate edge distanc

e between bol es s u c h that n o addit

i o n a l h o l es h ave b een added or ex tr a rivet
s u se d to fill stop d r illed bole s in the r ·oo t fitting

. Any blade that h as cracks (es pe cia ll y around the root of the blade)

, extra

r i vets, o r s top drill ed holes mu s t be removed from serv ice
. If a n y of t h ese defect

s arc found

, remove the blade from service

a nd replace with an ainvort
h y p a rt . Record th e r es ult s in sec tion 4 o f this se rvice bulletin. 2.3 With

t h e o utb oard main rotor blade

r e m ove d , in s p ect th e blad e for de l am in at i o n u s in g a tap test. 2.4 Use a metallic coin or tap h a mm e r to lightl y tap
t h e blad e in th e a r eas that a r ·e bonded. Pa y particular atte n tio n to the inbo ar d I2 inches (.3 0 4 m ) on th e top and bottom. Mark
a ll delaminated areas with a grease penci

l or c h a lk . Delaminated areas will h ave a duller, lo w pitched sound when compa

r ed to areas that are no t delaminated. The

' rn a • a l so h ave as on y or l oose fe e lin when ressed w ith the hand. 2.5 No delamination

i s permitted on the inboard 12 inche
s (.305m). Delami
n at i on
i s p erm itt ed outboard of this area provided the total d e l a min a t e d areas d o n ot exceed IO in 2 (.254m

2 ). Record the results in sect
i on 4.BRANTLYINTERNATIONALINC.SERVICEBULLETINNo:111SERVICEBULLETINPAGE:3/43DailyInspections3.1Beforethefirstflightofeachday,visuallyinspecttheoutboardmainrotorbladeforcracksandwrinldingoftheskin.Payparticularattentiontothebladerootarea,theareaaroundthelead/lagdampermountingfork,andthebladetrailingedge.3.2Nocracks,nicks,orwrinldingoftheskinarepermitted.Nocreasesorbendsarepermittedinthetrailingedgeoftheblades.Ifanyofthesedefectsarefound,removethebladefromserviceandreplacewithanairworthypart.BRANTLY INTERNATIONAL INC. SERVICE BULLETIN No: 111 I sERVICE BULLETIN

I REVISION:

- PAGE: 4/4 4 Inspection Report for SB-111 Please complete this repo rt for eac h outboard main rotor blad e a n d se nd it to Brantly Int. Use the contact inform atio n g i ve n in this service bu ll eti n .Describe the cracks and d e l a min at i on as mu c h a s p oss ible a nd u se the figure

t o c r e ate a sl<e tcb of th eir
l ocat ion s. H r

I r. e acopter

n o rm a tion Re2

.# Name Te l .

Se rial# TTIS Address E-mail BladeTTIS **~**2 n (. J J 4 0 r - ; - No Delamination : Permitted In This Area R es ult s/ O esca- iptian

o fCuc
k s an d Delamin at ion

Dat e Blad e TT @ In sta llati on **~**Bonded AreaBrantly International B-2 Main Rotor Blade Root Skin Inspection page
1 of 7 1 . T ec hn iq u e Numb
e r : ET002

3. Component

t o b e exa m ined: P/N 248-101

, 248-202

, and 248-404 main rotor blade (M RB) assemblies. 2. T ec hniq ue D a t e: 11/07 4 . Ar ea of E xa min a tion

: At fastener locations
in the upper and lower surfaces of the 2024-T3 aluminum skin

. 5. P u r p ose of Exa min ation: To detect skin cracks propagating from the fastener holes at various locations, thus preventing separation of the skin assembly and possible control loss of the aircraft. 6 . T ec hniqu e Wri tte n B y: Todd L. Jackson 7 . R e quir e d e qu

i pm e nt a nd tooling

: a. A single channel impedance plane eddy
c u r r ent

i nstrument. 1. The ins t rument used to d e v e
l op
t h
i s p rocedu

r e was the GE Phasec 20 wi t h a 12 pi n LE M O-to- BN C connector adaptor.
A comparab

l e

i m pe dan ce p
l a ne

i nstr u ment that

t hat can obtain eq u ivalen

t s e n s
i t ivit y c an be used. b. An absolute, shielded, microtip pencil probe with a stra

i ght

, 45 or 90 degree drop and a B N C-t o m

i crodot cable

. 1. The probe used to deve

l op this procedure was a MMP 445-40FX 50-500 KHZ and can be obtained from Olympus NOT (see paragraph

d . 1 . for contact information). Comparable probe with a microtip diameter may be used. 2. Cover probe coil wear surface with Teflon Tape, Temp-R-Tape

, Type T,

. 006 inch thick by 1 inch wide adhesive backed or equivalent-available from: Furon 29982 Ivy Glenn Drive Laguna Niguel

, CA 92677-2004

or Furon-CHR Division 407 East Street New Haven

, CT 06509

- 9988 c . A circle template made of non
- conducting material to guide the probe concentrically around the fasteners will be used. A Pickett No. 2100i circles inking template, commonly found at drafting supply stores, was used to develop this procedure

. d . A calibration standard PN

. ET002 (see figure
1 ). 1. Can be locally manufactured
or obtained from Olympus NOT (former

l y N OT Engineering Corporation)
at: 19620 Russell Rd Kent, WA 98032 Phone (1) (253) 872-085

7 e. Su

i table work surface to posi

t ion
t h e r emoved blade for inspection. 8. Ba s
i c Eddy C urr e nt In s trument Operating Paramet

e rs (Pha sec 20)

: a. Turn Instrument on by depressing the on (green) button. b . Press the menu button to access the operating parameters

. Verify that the following parameters are set for initial instrument calibra tion

. Refer to the instrument operating manual for parameter adjustment procedure. Note- The parameters listed below will vary slightly in description from one instrument make and model to another. ( FREQ

) (1) GAIN XY1 set to 30

. 0/45

. 0 ( 2 ) PHASE

1 • set to 0 ( 2 ) FREQ1 kHz set to 200 kHz ( 3) Filter set to BP LOCK

. (4) HP / LP filters set to DC/30

. 0 . (5) INPUT GA

I N1 set to High

. (6) PROBE1 set to Absolute

. (OUTPUT) (1) ANALOG 0/P 1 se t t o X1
. (2) ANALOG 0/P 2 set to X1
. (ALARM) Optional (TRACE DISP) (1) DISPLAY set to Spot. (2) GRATICULLE set to Grid 2 . (3) SPO T XY set to 115/-30

. (4) SPOT INFO set to Non e . (5) PERSIST set to 5
. 0 s. (6) SWEEP set to 5
. 0 s.

( MEMORY

) See Note
1 ( PROBE

) MODE set to Normal Single

. PROBE ID N / A , U nknown. LOAD JJH set to 120 or balance hold

. DRIVE dB set to +8 BALICLR MOD set to Sing

l e .Bran

t / '{_ Interna
ti o nal B- 2 Ma i n Rotor Bl a de Root Ski n lnsJJec

t ion

I page 2 o f 7 9. Ove
r v i ew of the

I nspection

: a . Surface eddy current inspect to detect cracks in the skin assembly on the upper and

l ower surfaces of the main rotor blade (M RB)

, adjacent
to the heads of the MS20426

- AD3 a nd AD4 rivets in the following areas (see Figure 2) : 1. At the rive
t ed area common to the hinge block attach fitting, sub-divided into fastener spacing configurations

, and 2 .at the riveted row common
to the spar

. Figu
r e 1 - Ca li b r a ti on Standa

r d E T 002 D e t ails j
300 "

**~**

. 125
" **~~** . 30 " + ... . 50 " +!+

. 50" **~l+- 50** **!+- 50** **-+**.. . 50 " -

FLAG NOT ES T

MA C HINED OUT OF

. 1 25" 2024- 0

1 T3 ALUMINUM

P LA TE

. :r:

100 ° COU NTER SINK ALL 1 . 00 "

(.) FASTENER LOCATIONS 1- 0 20 " 4

0

. 130
" EXCEPT LOCATIONS

5 . /z _j_ FABRICAT

E FROM

. 016
" T HICK MAX

. **~' ~~** **~~ ~~** **~~** -.--

2 2024-T3 CLAD ALUM

I NUM **~** SHEE T. 100 ° DIMP
L E **~-**

t COUNTER SINK ALL EXCEP
T . 980
" **~ ~CHr** 

3
. 00 " FASTENER LOCA T

I ONS 5 . M

I N .
MS20426-AD3 RIVETS (3/32

" /

3 DI AMETER)

. MAKE
S HO P **~**NOTCH
B NO TCH **~** HEADS% D X 2 D STA N DARD

. \,

2
. 00 " MS20426-AD4 RIVETS

(1 / 8 " 50" {' f.\ **f.'\.~_/.\ ~~**  {'

4 DIAMETER)

. MAKE SHOP • •

j HEADS% D X 2 D STANDARD

. . st .. J{--' **~,l f'-.-1** **\./**01" \._

5 STACK DRILL

. 200
" DIAM E T E R AND DEBUR

. _l_ 4 4

4 ET 002

- XXX **~** VIBRO-ETCH OR ELECTRO1 ..... 60 " --. ._

. 80 " _.

. 3o

· l.-<1)/*016

" 6 ETCH PART NUMBER AND l+-

. 50" -+ +

. 50 " -+ SERIAL NUMBER

I N TO TOP --+

. 300" ..... __. .109" SURFAC

E . NOTCH DIMENSIONS (INCHES) NO T CH LENGTH

WIDTH

DE PTH A

. 200
" MEASUR

E D ( . 035
" FROM EDGE OF COUN T ER SINK DIMPLE

)

. 010
" MAXIMUM

T HROUGH B EDGE OF FAS TE N E R HOLE TO EDGE OF FAS T ENER HOLE

. 010
" MAXIMUM THROUGH c EDGE OF FAS T ENER HO LE TO EDGE O F SH E ET METAL

. 010
" MAXIMUM THROUGH D

E DGE OF FASTE NER HOLE TO EDGE OF SHEET METAL .010
" MAXIMUM

T H ROUGH NOT E- NO TCH LOCAT

I ONS MUS T BE WITHIN+/-

0
. 005 OF T H E CENTERLINE OF T H E HOLE

. DIMENSIONAL

T OLERANCE (INCH
E S ) x

. xxx = + / - 0
. 005 X

. XX = + / - 0
. 025 x

. x = + / - 0
. 0 5 0 ANG LE S : + / - 1 . 0 DEGREE SURFACE ROUGHN

E SS = 63 Ra OR BETTERBrantly International B-2 Main Rotor Blade Root Skin Inspection Figure
2 : Fastener Locations
at Hinge Block Fitting and Spar Areas SKIN- TO-HINGE BLOCK FASTENER

A R EA "A" (SEE FIGU R E 3) SKIN- TO-S P AR FASTENERS
IN AREA

" B" (SEE FIGURE 3) K IN FORWARD EDG SKIN B LA D E RO O T **~**BLADE
T

I P Figure
3 : Fastener Identifi

c ation and Corresponding Probe Calibration Positions on ET002 **~**SCAN PATT E RN **~ ~** USING PROBE GUIDE \:;:::/ (SEE FIGURE

5 ) • PROBE POSITION
SKIN EDGE LINE AREA

" B " FASTENERS
PRO BE POSITION

8 PRO B E P OS

I TI ON 2 0

0 0 PROBE POS ITI O N 1 ee 91NSUFFIC

I ENTIL Y S P ACED <D(D
,' AREA

" A " FASTENERS FASTENERS, AREA

" A ", 6d),' SEE PAR. 12 AND 13 <l)SUF FICIE NTL Y SPACED

,' KNOWN LOCATIONS OF FASTENERS, AREA

" A " ,

I SKIN CRACKS EMANATIN
G SEE PAR. 14 AND 15

1 FROM FA STE NERS 0 SK

I N - TO
- SPAR FAS TE NERS e: LOCA T E D IN AREA

" A " I AREA

" B ", S E E P A R. 16 AND 17 t..:·;..;;;-'------------'

PRO BE POSITION

4 PROBE POSIT

I ON 5 @ N OTCH
8 t 10
. Instrument Calibration for Inspection of Skin around Dampener Attach Hole (Area

" A " ) PROBE POSI TIO N 6 @N O T CH A a . Turn

i nstrument on and ensure the basic operating parameters are set (see paragraph 8). b . Place Teflon tape over probe coil. Connect the probe to the instrument and select
a balance load.
p age 3 of 7 LEADI
N G EDGE TRAILI
N G EDGE PROBE POSITION

9 @NOTCH

D PROBE POSI T ION 7 c . Place the probe on position

1 of the E T002 reference standard

, and press balance

/ lift - off
.
I f needed

, ad
j ust Spot XY position

t o bring flying dot into position as shown in figure 4. d. Lift the p ro b e coil approx

i mate

l y 1" fr om the surface

o f th e r eferen
c e standard. The signal

t ra ce should move h o r i zonta

ll y from right

t o

l e ft on
t he scr een from the ba

l anc e po

i nt sho w n in figu
r e 4. N ote: T he li ft -off phase angle w il l be autom atica lly se t as s hown in f ig ur e 4, wh e n bala nce / lift off is p ressed and h e
l d. If th e

i nst r ument does
n ot h av e an "au
t o phase

" feat ur e, ro t at e t he p h ase angle unti

l the des

i re d resu

l ts are obtained. e . Place th e probe on probe position

2 of the ET002 reference standard (see figure 3) and sc a n around

t he hole using the circle template as a probe guide as shown in figure 5. Observe

t he screen while scanning

. The flying dot should not move more than 1-2 division lines vert ically or horizontally from the balance point. Note

:
I f the dot drifts more than 1-2 divisions horizontally

, the probe may be tilted excessively

. If the dot drifts more than 1-2 divisions vertically

, it is positioned too close to the edge of the fastener. f . Use

t he same circle template hole to scan around the hole at pro b e position

3 and over notch C (see figure 3). The s ig nal trace shou

l d

l ook simi

l ar to that shown in figu
r e 4. Ad
j us t the

i nstrument gain to obta

i n an 80% screen hei g h t ve rt

i ca

l movement from

t he no tch

.Brantly International B-2 Main Rotor Blade Root Skin Inspection

p age 4 o f 7 F i gur e 4 : Screen Present

a tion s from Lift-Off and No tc h es A , B and C VERTICAL (Y) DIVISION LINES ..... ··· t .. **···· !······** **!·······~··** I

. SIG N AL F R O M NOTCHS

A , B A N D C (PROBE POS

I TIONS

3 , 5 AND 6) THAN 1-2 DIVISIONS VERTICALLY OR

! ! ! ! ! ! ! 1 ! !
i 1 !

:

1
! HORIZONTAL

Y FROM BALANCE POINT

... , ......
, ......**~···**
**··· ···** **·:- ······** **···**

:

: ···.····-

:- ··· · · **··· ···-** 
**--1 --·+·····~** ......**~.ft**

• • •• DURING SCAN OVER DEFECT FREE AREA

i 1
i

i 1

! .••·

' '' ! ''

' ''' '! ·····

! ······

: ···"'

! '"''"' '''''

' ! ''"' ''!··

· · ··:

· · · ···•

! ••" .. !'' "'"

! ''"''!'' HOR

I ZO N TAL (X) DIV

I S IO N LI N ES Figure
5 : Proper Circle Sel e ction for Probe Guide CIRCULAR SCAN PATTERN MICRO TIP PROBE

1 1 MICRO TIP PROBE FASTENER HEAD CALIBRATION NOTCH

" A"
CALI B RATION NOTCH

" C " 11 . Inspection of Skin around Dampener Attach Hole (Area

" A" ) CIRCL E TEMPLATE USED AS A PROB E GUIDE a. Place the same circle template hole (selected
in step e. of paragraph 10.) concentrically over dampener hole as shown

i n f i gure 5. b . Press
b ala n ce/ li ft off to ba

l a n ce th e

i nstrument

, if needed. Ad
j ust Spo
t XY posit

i on
, if neede
d , t o b ring

f l ying dot i n t o po s
i t io n as shown in figure 4. c. Scan probe around the ho

l e while observing the instrument screen

. d . Turn MRB over and repeat the preceding steps on the opposite side of the blade

. e . Any signal obtained
in preceding steps of this paragraph that exh

i bits a rapid upscale vertica

l movement equal to or exceeding 50% screen height will be cause for rejection. f . Dete

r mine the length or end(s) of the crack by scanning back and forth across the length

u n t il the vertical trace r et urns

t o t h e balance poi n t and mark location

. Measu

r e an d r ec o rd t h e

l ocation and le n g th of the c r ack

.Brantly International

B - 2 Main Rotor Blade Root Skin Inspection page 5 of 7 12
. Instrume nt Calibration for

I nspection of Skin adjacent to the Insuffici en tl y Spaced

F as t eners

( Area

" A " ) a . Turn instrument on and ensure the basic operating parameters are set (see paragraph 8). b. Place Teflon tape over probe coil. Connect the probe to the inst rum ent and select
a bala nce loa d . c . Place the probe on position

1 of the ET002 reference

s t andard

, and press balance/lift-off

. If needed

. adjust Spot XY position to bring flying dot into position as shown in figure 4. d . Lift the probe co

i l approximately

1 " from the surface of the reference standard

. The s
i gnal trace should move horizontally from right to left on the screen from the balance point shown in figure
4 . Note: The

l ift-off phase angle will be automatically set as shown in figure
4 , when balance/lift off is pressed and held

. If the instrument does not have an
" auto phase

" feature

. rotate the phase angle until the desired results are ob ta ined. e . Place the probe on position

4 of the ET00 2 reference standa rd (see figure 3) and scan around the ho

l e using the circle template as a probe guide as shown in figure 5. Observe the screen while scanni ng
. The

f ly ing do t s h ould not move mor e than 1-2 divisio
n

l in es vert

i cally or horizonta

l ly from the balance po in t. Note: If the dot drifts more than 1-2 divisions hor

i zontally, the probe may be tilted excessiv ely

. If the dot drifts more than

1 - 2 divisions vertically

, it is positioned too clos e to the edge of the fastener. f. Use the same circle template hole to scan around the fastener

a t probe position

5 and over notch B . The signal trace should look s
i milar to that shown in figure
4 . Adjust the instrument ga

i n to obtain an 80% screen he

i ght vertical movement from the notch. 1 3. In s pe ction of Skin adjacent to the In s ufficiently Spaced

F aste ners (Area

" A " ) a. Pl ace the same circle temp

l at e hole (sele cted in step e. of paragrap

h 12.) concentrically over the fa s t e n er adjacent to the skin being inspected (similar to the example

g
i ven in f i gure 5) . b . Press balance/lift off to balance the instrument.

If needed

, adjust Spot XY position to bring flying dot into position as shown in figure
4 . c . Scan probe around the fastener while observing the instrument screen

. d . Repeat the preceding steps of this paragraph until the skin is inspected at all

l i ke spaced fasteners

l ocated in Area " A". e. Turn MRB over repeat
p re ced in g steps of this paragraph until the skin is in spected at all

l ike spaced fastener locat

i ons in Area "A"

. e . Any signal obtained
in preceding steps of this paragraph that exhibits

a rapid upscale vertical movement equa

l to or exceeding 50% screen height will be cause for rejection

. f . Determine the length or end(s) of the crack by scann

i ng back and forth across the length unti

l the vertical trace returns to the balance point and mark location

. Measure and record the location and length of the crack

. 14
. Instrument Calibration for In s p ec tion of Skin adjacent to the Sufficiently Spaced

F asteners (Area

" A " ) a. Turn

i nstrum ent on and ensure the basic operating paramete
rs are set (see paragrap

h 8). Place Teflon tape over probe coil. Connect the probe to the instrument and se

l ect a balance load. b . Place the probe on position

1 of the ET002 reference standard

, and press balance/lift-off

. If needed

, adjust Spot XY position to bring flying dot into position as shown in figure
4 . c. Lift the probe coil approx

i mately

1 " from the surface

o f the reference standard

. The signa

l trace shou

l d m o ve horizontally from

r i ght to left on the screen from the balance point shown

i n figure
4 . Note: The

l ift-off phase ang

l e should be automatically set as shown in figure
4 , when balance/lift off is pressed and held. If the instrument does not have an
" auto phase

" feature, rotate the phase angle until the desired results are obta

i ned. Conti nued on pag e 6B r antly International

B - 2 Main Roto r Blade Root Skin In s p e ction page 6 of 7 14
.
I nstrument Ca libr at

i on for

I nspection of Skin Adjacent to the Sufficiently Spaced Faste
n ers (A r ea
" A " ) Continued from page 5 . d. Place the probe on position

6 of the ET00 2 reference standar
d (see figure 3) and sca n around the fastener using the circle template as a probe guide as shown in figure 5. Observe the screen while scan ning. The fly in g dot should not move more than 1-2 division lines vertica

l ly or horizontally from the balance point. Note: If the dot drifts more than 1-2 divisions horizontally, the probe may be tilted excessively.

If the dot drifts more than

1 - 2 divisions vertically

, it is positioned too close to the edge of the fastener. e . Use the same circle template hole to scan around the fastener at probe position

7 and over notch A (see figure 3) . The signal trace should look similar to that shown in figure 4. Adjust the instrument gain to obtain an 80% screen height vertical movement from the notch

. 1 5.

I nspect

i o n o f S k in A d j acent to t h e S uffi c ientl y Spaced

F as t e n e r s (Ar ea
" A ") a. Place the same circle

t em plate hole (selected
in step d. of paragraph
14 .) concentrica
lly over the fastener adjacent

t o t he skin being

i n spected (similar to the example given in figure 5) . b . Press balance/lift off to balance the instrument.

I f needed

, adjust Spot XY position

t o bring flying do t i nto position as shown in figure
4 . c . Scan probe
a r ound the fastener while observing the instrument scr een

. d. Repeat the preceding steps of this paragraph until th e skin

i s inspected
at all like spaced fasteners

l ocated in Area

" A"
. e . Turn MRB over

r epea

t the preceding steps of th

i s paragraph until the skin

i s in spected at all like spaced fastener loc at

i ons in Area "A". f . Any signal obtained
in preceding steps of this paragraph that exhibits

a rapid upscale vertic al movemen

t equal to or exceeding 50% screen height will be cause

f or rejection. g . Determine the length or end(s) of the crack by scanning back and forth across the length until the vertical trace returns to the balance point and mark location

. Measure and record the location and length of the crack

. 1 6 .

I ns t r u me nt C a li bra ti o n fo r
I ns p ec ti o n of Sk

i n A djace nt to th e S kin -to
- s p a r Faste
n e r s (Ar ea
" B " ) a. Turn instrument on and ensure the basic operating parameters are set (see paragraph 8). b . Place Teflon tape over probe coil. Connect the probe to the

i nstr ument and select
a balance load. c . Place the probe on position

1 of the ET002 reference standard

, and press balance

/ lift-off

. If needed

, adjust Spot XY position to bring flying dot into position as shown in figure
4 . d . Lift the probe coil approximately

1 " from the surface of the reference standard

. The signal trace should move horizontally from right to

l eft on the screen from the balance point shown in f i gure 4. Note

: The lift-off phase angle will be automatically
se t as s hown in figure
4 , when balance/lift off is pressed and held. If the instrument does not have an
" auto phase" feature

, rotate the phase angle until the desired res ult s a r e obtained. e . Place

t he probe on position

8 of the ET00 2 reference standa rd ( se e figu re 7) and scan around the fa stener us in g the circle template as a probe guide
a s shown in figure
5 . Observe the screen while scanning. The flying dot sho u ld not move more than 1-2 division lines vertically or horizontally from the balance point. Note

: If the dot drifts more than

1 - 2 d
i visions hori z onta

ll y , the probe may be
t i lted excess

i vely

. If the dot dr

i fts more than

1 - 2 d
i visions vertically

, i t is positioned too c
l ose to the edge of the fastener

o r the edge of the skin. A s
i gna

l ( l i ke the one shown

i n figure
6 )

i s caused by the prob e being

i n close prox

i m

i ty to the edge of the sk

i n and must not be confus
e d w

i th the notch
s
i gnal or a crack

. f . Use the same circle template hole to scan around the ho

l e at p robe position

9 and over notch D (see figure 6) . Th e signal trace
s h ou

l d

l ook similar to th at shown in figure
6 . Adjust the instrument gain to obtain an 80% screen he ight vert

i ca

l movement from the notch

.BrantlyInternationalB-2MainRotorBladeRootSkinInspectionpage7of7Figure6:ScreenPresentationsfromLift-Off,SkinEdgeandNotchD1......THEFLYINGDOTSHOULDNOTMOVEMORE···[······[······r······[····..;LIFT-OFFLINE,..y.·.....l/;;;;;·j..;,;'''·.FLYINGDOT.THAN1-2DIVISIONSVERTICALLYOR20%;.;.;;--"'i.;;;/I[''''''HORIZONTALYFROMBALANCEPOINTjliiii[:i.,...DURINGSCANOVERDEFECTFREEAREAlL!L.....!1IlILJ:::HORIZONTAL(X)DIVISIONLINES_/..v---Figure7:ScanTechniquearoundArea"B"FastenersCIRCULARSCANPATTERNIIMICROTIPPROBEIIET002lCIRCLETEMPLATEUSEDCALIBRATIONFASTENERASAPROBEGUIDESTANDARD\CALlBRATIONNOTCH"D"EDGEOFSKIN17.InspectionofSkinaroundSkin-to-SparAttachFasteners(Area"B")a.Placethesamecircletemplatehole(selectedinstepe.ofparagraph16.)concentricallyoverthefastenerasshowninfigure7.b.Pressbalance/liftofftobalancetheinstrument,ifneeded.AdjustSpotXYposition,ifneeded,tobringflyingdotintopositionasshowninfigure6.c.Scanprobearoundthefastenerswhileobservingtheinstrumentscreen.d.TurnMRBoverandrepeattheprecedingstepsontheoppositesideoftheblade.e.Anysignalobtainedinprecedingstepsofthisparagraphthatexhibitsarapidupscaleverticalmovementequaltoorexceeding50%screenheightwillbecauseforrejection.f.Determinethelengthorend(s)ofthecrackbyscanningbackandforthacrossthelengthuntiltheverticaltracereturnstothebalancepointandmarklocation.Measureandrecordthelocationandlengthofthecrack.18.Reportinga.Reportinspectionresultsto:BrantlyInternationalInc.,621S.RoyalLaneSuite100Coppell,TX75019-3805,USAb.IncludeaircraftS/N,MRBPN.,MRBS/N,MRBtotaltimesincenew,locationandlengthofcrack(s)inreport.TechniqueApprovedBy:ToddLJackson,CoLlll,JETS,Inc.Date:11/01/2007TechniqueAcceptedBy:Date: