Piper Aircraft Corporation 

Vero Beach, Florida, U.S.A. 

SERVICE No. 910A I 

BULLETIN 

********************************** * .. * * PIPER CONSIDERS .. . :- * 

: -· COIV1PLIANCE MANDATOflY : 

********************************** _________________________________ o_a_t_a ______ Qctobe~Q~8~---------~s~-----

(Service gulietin No. 910A supersedes and vc cs Service ~:l ~t n No. 910, 

dated May 15, 1989 and the affect::d pcrticr:s of Ser·1ice 5:!.! ll etin ~ic . 5288, 

dated March 10, 1978) 

This Service Bulletin is divided in two Parts. Check each Par: for applicable 

compliance time, purpose and instructi ons. 

SUBJECT: Wing Lift Strut Assembly 

Inspection/Replacement 

REASON FOR REVISION : To revise models affected, serial numbers affected, 

compliance time, purpose, instructions and to add 

Part II. 

APPROVAL : .The technical contents of this Service Bulletin have 

been approved by· the F. A. A.· - · --

MODELS AFFECTED: _,_. ·. ··-

PA- 18/18A Series. Super Cub · NOTE: Includes All Serial 

No. L- 21A, L- 218, & L- 18, 

Seaplane, Agricultural, and 

Military Versions 

PA-19 Super Cub 

PART I 

SERIAL NUMBERS AFFECTED: 

18-1 through 18-8309025, 

1809001 through 1809032, 

1809034 through 1809040 

19-1, 19- 2 and 19-3 

COMPLIANCE TIME: Before next flight and each twelve (1 2) month period 

thereafter. · · NOTE:· If the inspection requirements of Service Bulletins No. 5288 or No. 910 have 

been accomplished within the last twelve (12) months or if the wing lift struts 

are new and were installed within the last twelve (12) months, inspection is 

required no later than twelve (12) months after the last inspection or new lift 

strut installation as the case may be. If the aircraft is new with original 

l ift struts installed, the repetitive inspection begins when the aircraft is 

twelve (1 2) months old . 

(OVER ) 

ATA: 5701 
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SERVICE BULLETIN NO. 910A PAGE 2-OF 5 -.. ,_: "f!,".i ~,. '> ':-

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PURPOSE: Piper Aircraft has determined that the five (5) y~ar 

repetitive fnspection interial'reciuired in service Bulletins No. 528B and 910 

may be inadequate for the timely detection of serious wing lift strut 

corrosion. This corrosion, ·if allowed to progress, may lead to failure of the 

wing lift strut, and the possibility of loss of wing structure integrity. 

The compliance time for the corrosicn inspection and treatment is reduced to an 

interva l not to exceed twelve (12) months frcm the last insp-ection or the first 

use of new 1ift struts . Initially Piper deems it necessary to rep lace 

existing wing lift strut with new sealed wing l ift struts a1:. a date not to 

exceed twenty- four (24) months. (See Part II) 

Part I of this Service Bulletin provides an inspection an corrosion impediment 

procedure to detect and t reat possible wing lift strut corrosion . 

INSTRUCTIONS: 

1. Remove wing lift struts and accomplish the inspection per inspecti on 

procedures on Sketch "A". Caution: All aircraft utilizing "cuffs" at the 

wing lift strut roots (top and/or bottom) should take extra care in 

inspection for external corrosion in the areas covered by the cuffs. 

2. Inspect forks, clamps, fairleads and jury struts for condition and replace 

as necessary . All attaching hardware should be replaced. 

3. After completion of the inspection procedure, but prior to the corrosion 

impediment procedure of the wing lift struts, turn each wing lift strut 

upside down and tap gently. This procedure is necessary to remove any 

water, debris, or corrosion particles which may have accumulated.· ;-- . 4. Lift strut tubes indicating presence of internal corrosion and which fail 

the inspection procedure must be replaced with new wing lift struts called 

for in PART II of this Service Bulletin. Note: Should corrosion be 

apparent from the outside, (rust pin holes or large rust stains) strut must 

be rep 1 aced even if strut passes the inspection procedure. _=.,5:.::·· 5. Treat (corrosion impediment) each wing lift strut per the instruction 

procedure note on Sketch-"A". Treatment must coincide with each inspection 

as outlined in the compliance t ime above. 

6. Lift strut assemblies which have been factory treated with corrosion 

preventive measures are identified by the installation of a cherry lock_ 

rivet installed at the upper (wing attachment) end. 7. Alternate oreservative materials: In addition to the "Val oil" and 

''Lionoil" (preservatives), it is permissib le to use the following alternate 

preservatives - Paralketone, linseed oil or any alternate preservative~ 

that satisfy the requirements of Federal Specification TT-S-1 760 . NOTE: 

Upon successful completion of the inspection procedure and treatment, - reinstall lift struts on aircraft. 

8. Check aircraft rigging and adjust as necessary, use Piper Service Memo 19 

(attachment A) as required to accomplish the proper rigging. 

9. Make an appropriate logbook entry· of compliance with this Service Bulletin . 
SERVICE BULLETIN NO. 910A 

MODELS AFFECTED: 

PA-18/18-A Series Super Cub 

NOTE: Includes All Serial 

No . L-21A, L-218, & L-18, 

Seaplane, Agricul t ural, 

and Mi litary Versions 

PA-19 Super Cub 

PART II 

PAGE 3 OF 5 

SERIAL NUMBERS AFFECTED: 

18-1 through 18-8309025, 

1809001 through 1809032, 

1809034 t hrcugh ~80~0 40 

19- 1, 19-2 and 19-3 

COMPLIANCE TIME: To coincide wi th the next regularl y scheduled 

inspection event or at next replacement of the wing lift strut, but not to 

exceed twenty-four (24) months from the initial inspection as called for in 

Part I of this Servi ce Bulletin. 

PURPOSE: Part II of this Service Bulletin announces the 

availability of new sealed wi ng lift struts which, when installed, will relieve 

inspection requ i rements of Part I of this Servi ce Bu 11 et in 

INSTRUCTIONS; 

1. Remove old wing l ift strut. 

2. Prepare, prime and paint new sealed wing lift struts to match aircraft 

before assembly. 

3. Inspect clamps, f airleads and jury struts for condition and replace as 

necessary. All attaching hardware should be replaced. 

4. Install new Sealed Wing Lift Strut Assemblies, Piper Part Number 89497-02 

(front) and Piper Part Number 89498-02 (rear) on each wing. 

5. Install "No Step" Decal , Piper Part Number 80944-02, at the base of each 

wing lift strut 1n the approximate location of the original "No Step" 

deca 1. 

6. Check aircraft ri gging and adjust as necessary. Use Piper Serv i ce Memo 19 

(attachment A) as required to accomplish the proper rigg i ng. 

7. Upon successful completion of Part II of this Service Bulletin, make an 

appropri ate logbook entry of compliance. 

MATERIAL REQUIRED: As required by inspection for Part I or as required by 

Part II , two (2) each Front Wing Strut Assemblies, Piper Part Number 89497-02, 

two (2) each Rear Wing Strut Assemblies, Piper Part Number 89498-02, and four 

(4) each "No Step" Decal, Piper Part Number 80944-02. 

AVAILABILITY OF PARTS: Your Piper Field Service Facility. 

I EFFECTIVITY DATE: Th is Service Bulletin is effective upon rece i pt. 

(OVER ) 
SERVICE BULLETIN NO. 910A PAGE 4 OF 5 : 

SUMMARY: Any applicable factory participation will remain in 

affect for a period of time not to exceed 180 days from the effective date of 

this Service _BulJetin •. ___ : .. __ . _ -----... - - ._ __ __ ·: .. : 

Special pricing is in effect for the Front Wing Lift Strut, Piper Part Number 

89497-02 and for the Rear Wing Lift Strut, Piper Part Number 89498-02, for 

twenty- four (24) months from the effective date of this Service Bulletin. 

Please c~ntact your Factory Piper Fie ld Service Facility to make arrangments 

for compliance with this Service Bulletin in accordance with the compliance 

time indicated. 

NOTE: If you are no longer in possession of this aircraft, please forward 

this information to the present owner/operator and notify the 

factory of address/ownership corrections. Changes should include 

aircraft model, seri al number, current owner's name and address. 

Corrections/changes should be directed to: 

·. 

Piper Aircraft Corporation 

Attn: Customer Services 

P.O. Box 1328 

Vera Beach, Florida 32961-1328 

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SERV ICE BULLETIN NO. 910A PAGE 5 OF 5 

~~~=r VIEW OF MAULE FABRIC TESTER 

;-1 Rivet NAS1738B4-4 (On Centerline Of •fACTORY TREATED• Strut) 

r:?.~ Shee: ~~~al Scr~ M~1861-44 (On Cerrtenine: ~"FIELD TREATED" Strut) 

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SOTTOM VIEW OF FRONT LifT SJEUT ASSEMBLY 

Rivet NAS173884-4 (On Canter1ine OF ·FACTORY TREATED• Strut) 

Sheet MetaJ Screw M$51861-44 (On Canter1ine Of ·etEL.O TREATED· Strut) 

BOTTOM VIEW Of BEAR LifT STRUT ASSEMBLY 

INSPECTION PROCEDURE 

1. Securely tape a sheet of thin 1 1• inch graph paper to the lower 11 inches of the top and bottom surfaca on all wing lift 

struts. 

2. Using a Maule •Fabric Tester- and holding tool normaJ to strut contour, apply pressure at a scaie raading of SO in in 

each of the grid blocks. 

3. Remove the paper and inspect the rift strut tubes. A pe~ible dent will appear if internal corrosion is present If any 

dents are found, be C8rtain the dent are in the metal by carefully removing the paint. 

a. Lift strut tubas indicating the presence of any precptible dent in the metal must be replaced with a new lift 

strut a5$embly before further flight. 

b. If no dents appear in the metal, the lift strut may be considered airwothy. 

NOTE 

Further internal corrosion may be impeded per the following procedure: 

a. Remove lift strut from aircratt. 

b. Inject o~e quart of Vaioil, Uono~ Multi-Purpose L-1. Unseed Oil, Paralketone 

or any alternate preservative ccnf04'ming to Fadera !Specification TT-S-1760, 

into the bolt hole at the top of the ~rut. 

c. Plug the bolt holes and slosh oil until interior of strut is throughfy coated. 

d. Drain oil from strut (through bolt holes) and install MS51861-44 sheet metal screw, 

as shown, for future identification. 

e. Reinstall strut to aircraft and rig. 

4. Record lift strut inspection in aircraft logbook. 

SKETCH "A" 
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., REFERE!'!CE SERVICE BULLETIN 91 OA 

SERVICE 

RIGG~ PROCEDURE 

Piper PA-18 and PA·l9 

ATIACHnENT "A" 

MEMO 

Sernce Memo No. 19 

R.!GGING PROC~Dl'1tE: Rz!se ~e forward part of the airplane eo that the wheels are just 

c~ear o! the ground and st:;)port it by preps under c::e z_ ::=.c r.a:lciing g-e~= fit:ing-3. R~ise the 

t.aU to approximate level fligilt position and support it ~!'e . 

LEVELING: Level the ai:rplane as follows: Drop plumb bob from P. K. Screw in door frame 

top chaxmel to intersect punch maJ:X in e:~closure door rear binge. 

OIHEDR.!L ANGLE: To checl: dihedral angle at the froat spar proceed as follows: 

Stretch a stri..ng along the top of the wt.o.p above the front spar, f:'om wing tip to wing tip, 

aDd draw it tight. 

CheCk the dimension vertically from the string to cop of fuselage front spar wing hinge fitting. 

For correct d!.hedral this dimension should be 3 f.l/8 iDches. 

To check !or equal dibed.ra1 iD each wing proceed as follows: 

Using the 30 inch level (witbour any spacer blocks) bold it spanwtse against the bottom of the 

wing under the front spar iD the space between the jury struts and lift strut attachments. 

Noce the position of the bubble aDd do the same on the other wing. Re-adjust the front struts 

aDt1l both wings show the same amOtllJt off level, being careful with each adjustment to set 

tbe lett strut out the same num.ber of turns as tbe r1gfx one is sec in. and vice versa . 

WASH our: To adjU8C the wash o~ in the wings (dlbedral of the rear spar) proceed as follows: 

Set a 3/8 iDch spacer bloCk 011 top ot the 30 inch level at one end. Working on the rib adjacent 

to tbe outer eud of the ailerou. hold tbe level fore and att along the bottom of the rib with the 

spacer block at tbe rear and the front end of the location of tbe front spar. The correct wash 

out wtll exist wbeD the bubble is centered. Adjust the rear sttl%S in or out to obtain this 

condition. 

TAIL ASSEMBLY: With the airp!me in level position the sta.bill%ers should be leveled at their 

rear spars. The hin~ line should be straight from tip tu tip. 

Plumb the !in at the rudder hinges. 

PIPER AIRCRAFT -CORPORATIO-N.-- LOCK- HAVEN. PA .. U. S. A. 
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