SAIB NM-05-69

SPECIAL AIRWORTHINESS

INFORMATION BULLETIN

Aircraft Certification Service Washington, DC

U.S. Department of Transportation Federal Aviation Administration

SAIB NM-05-69 July 8, 2005 http://www.faa.gov/aircraft/safety/alerts/ This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin (SAIB) provides information to you, owners and operators of various Surplus Military airplanes (table 1) manufactured by Northrop Grumman Corporation . We used “Jane’s All The World’s Aircraft” reference material from 1954 through 1973, as well as information from operators to determine the various aircraft for incorporation in this SAIB.

Background

The California Department of Forestry has two Type Certificates for aircraft similar to the aircraft identified in this SAIB and includes models S-2F3AT and TS-2A. Their type certificates contain approved maintenance procedures for their aircraft based on military maintenance manuals and procedures available from the public domain. This SAIB provides information to all potentially affected operators, including those with airplanes that don’t have a US type certificate.

TABLE 1 Model Models with Variations for different Customers and Missions S-2F1 (S-2A) US-2A, S2F-1T (TS-2A), S2F-1S (S-2B US-2B), S2F- 1S1 (S-2F) CS2F-1, CS2F-2, S-2FT

TABLE 1 (continued) S-2F2 S-2C, US-2C, S2F-2P (RS-2C) S-2F3, (S-2D) E2-D, US-2D, S2F-3S (S-2E), S-2G, YS-2G, S-2T, CS2F-3, S-2F3AT, S2F-3T C-1 C-1A, TF-1, TF-1Q (EC-1A)

During annual inspections, an operator found the horizontal stabilizer mount fittings, P/N 89TM2060-1 and -3 had exfoliation corrosion.

While replacing those fittings, a fleet wide inspection of the operator’s aircraft found additional aircraft with corrosion. They repaired all corrosion.

The aircraft’s horizontal stabilizer structure has a semi-monocoque co nstruction. While other aspects of the construction of the horizontal stabilizer ma y have variations, the horizontal stabilizer mount fittings P/N 89TM2060-1, -2, –3 and –4 are generally common to all listed aircraft. We based our recommendations on dimensions taken from a Navy S-2G model aircraft.

Recommendations

We are concerned about corrosion and related cracking in the horizontal stabilizer mounting fitting of aircraft that may not have adequate maintenance programs. We have considered the consequences of horizontal stabilizer mount fitting corrosion and operator’s actions to mitigate the hazards for their fleet.

2 We highly recommend you perform annual inspections to visually inspect the horizontal stabilizer mount fitting for corrosion. The mount fittings can be found on the horizontal stabilizer 4.75 inches outboard of the airplane centerline on both left and right sides of the horizontal stabilizer at fuselage station

451.667. If you find any corrosion, you should repair or replace the part. You can perform the inspections under the military maintenance manuals (portions attached).

For Further Information Contact

John L. Cecil, Aerospace Engineer, FAA Transport Aircraft Di rectorate, LAACO, ANM-120L, 3960 Paramount Boulevard, Suite 100 Lakewood, CA 90712-4137;

phone: 562.627.5228; fa x: 562.627.5210;

email: john.cecil@faa.gov

- 15 HOLES TO BE DRILLED FROM MASTER DRILL PLATE #2T45429.

NOTE:

2.953 .312 .031 .250- .287 .062 R.(2)- 1.062 .500 R 312 89TM2060-3 SHOWN 89TM2060-4 OPP. • .437 (REF) REAM.5620-. 5630 DIA. G26-M-6-4 RUBBERSTAMP PART NUMBER AND ALL OTHER WARKINGS IN THIS REGION USE BOTH SIDES IF NECESSARY. DRILL *30 (126-.133) 21 HOLES .437(REF) SHOWN 89TM2060-1 89TM2060-2 OPP GRAIN OPTIONAL

Section 1III NAVWEPS 01-85SAD-3 RUDDER TRIMMER Skin Panels - Figure 3-36 Skin Repairs - Figures 3-32, 3-37, and B-1 through B-4 Beam Repairs - Figures 3-25 and 3-38 Rib Repairs - Figure B-6 and B-7 Principal Dimensions - Figure 3-35 Skin panels - Figure 3-31 Skin repairs - Figures 3-32 and 3-33 B-1 through B-5 Beam repairs - Figures 3-24 and 3-34 Rib repairs - Figures B-6 and B-7 Principal dimensions - Figure 3-30 Mass balancing diagram - Figure 1-7 Note For negligible damage see figure 1-3 RUDDER Figure 3-1. Tail Group FIN Skin panels - Figure 3-13 Skin repairs - Figure 3-4, 3-5, and B-1 through B-4 Beam repairs - Figure 3-15 and 3-16 Rib repairs - Figure 3-10, 3-17, 3-18, B-6 and B-7 Stringer repair - Figure 3-19 Principal dimensions - Figure 3-14 ELEVATOR Skin Panels - Figure 3-21 Skin Repairs - Figures 3-22, 3-23, 3-28, 3-29 and B-1 through B-5 Beam Repairs - Figures 3-24 through 3-27 Rib Repairs - Figure B-6 and B-7 Principal Dimensions - Figure 3-20 Mass Balancing Diagram - Figure 1-6 STABILIZER Skin panels - Figure 3-3 Skin repairs - Figures 3-4 and 3-5 Beam repairs - Figures 3-6, 3-7, and 3-8 Rib repairs - Figures 3-9, 3-10, 3-11, B-€ and B-7 Stringer repair - Figures 3-12, B-8 and B-9 Principal dimensions - Figure 3-2 138 Revised 15 September 1962

NAVWEPS 01-85SAD-3 Section III Fuselage Sta 450.75 Fuselage Sta 441.925 Fuselage Sta 451.667 See Fuselage Sta 478. 525 Fuselage Sta 500. 600 312 859 859

2. 750 5. 312 -

18.108 See view A 29.108

40. 108 Figure 3-2. Stabilizer Principal Dimensions (Sheet 1)

52.608 66. 108 See view C Elevator hinge center line

80.608

95.108 100. 108

124.483 109.608 See view D See view E

125.670 130. 108

138.858 SHOT DAMPER (LEFT SIDE) Fuselage Sta 485.744 center line of front 154. 008 Fuselage Sta 496.312 front face of rear beam Sta 153.53 17. 688 2. 593- beam Revised 15 December 1960

Section I NAVWEPS 01-85SAD-3 Water line 55. 5 - 10° 11/16 Center line of airplane. Chord line 1.080 ELEVATOR BALANCE TAB SUPPORT FITTING AT STA 100.108 AND 130.108 VIEW E

7.108 9.125 CENTER HOLD DOWN FITTING Elevator hinge center line. 150 VIEW B Chord line 8.1 Chora line VIEW D STABLIZER HINGE FITTING AT STA 124.483 Figure 3-2. Stabilizer Principal Dimensions (Sheet 2) Water line 55.5 at 0° incidence. Elevator hinge center line.

. 3906

3.20 FRONT TIE DOWN FITTING A Sta 1.3655 80.608 ., 5455 Elevator hinge center line. SAT STAR AN PITTE

4. 75. 3966 4. 823 4. 892. VIEW A VIEW C Chord line Center line of airpiane. 1.234 Chord line Revised 15 December 1960

Section Il NAVAIR 01-85SAD-4-2 Group Assembly Parts List FIGURE

AND INDEX PART NUMBER UNITS USABLE

PER ON NUMBER 12 3 45 67 ASSY CODE 11 - 25 89T2159-2 SKIN ASSY, RH

- 26 89T2159-36 • LEAF, BUTT HINGE /ALTERED FROM GOVT STD PART NO. MS20001PY6-4100/ /ATTACHING PARTS/

- 27 89T2159-69 PIN, STRAIGHT, HEADLESS /ALTERED FROM GOVT STD PART NO. AN253-2-4172/

- 28 8972159-34 • LEAF, BUTT HINGE /ALTERED FROM GOVT STD PART NO. MS20001PX2-4100/ 89TM2060-1 FITTING ASSY, FRONT TIE DOWN, LH 89TM2060-2 FITTING ASSY, FRONT TIE DOWN, RH

- 29 G26-M-6-4 BUSHING, SLEEVE

- 30 89TM2060-3 FITTING, LH 89TM2060-4 FITTING, RH 89TM1823-1 FITTING ASSY, MAIN BEAM TIE DOWN 30A G26-M-9-12 BUSHING, SLEEVE

- 30B - 31 89TM1823--3 89TM1286-1 FITTING ASSY, STABILIZER CENTER HOLD DOWN FITTING 89TM1286-5 FITTING ASSY, STABILIZER CENTER HOLD DOWN * VY

- 32 NAS464P9 37 BOLT, SHEAR /ATTACHING PARTS/ AN960D916L AN364-918 WASHER, NUT, SELF-LOCKING, HEXAGON: FLAT ....

• - * -

- 33 - 34 627-9-22 627-7-8 BUSHING, SLEEVE BUSHING, SLEEVE ....... 4 4

- 35A 35 89TM10057-3 G27-10-10 FITTING, STABILIZER TAB ACTUATOR MOUNT : ' BUSHING, SLEEVE /ATTACHING PARTS/

- 358 NAS1103-4 BOLT, MACHINE AN960-10 WASHER, FLAT • ..... 8 8

- *

- 36 121CSM10003-1 121CSM10003-2 FITTING ASSY, STABILIZER HINGE, LH FITTING ASSY, STABILIZER HINGE, RH 1N224

- 37 37A 89TM1006-1 121CSM10010-1 HINGE ASS, STA BOS: BUSHING

- 378 89TM1005-1

- 37C 89TM2067-1 HINGE ASSY, STA 124, 483

- 370 89TM10597-1 FITTING, BALANCE TAB SUPPORT /ATTACHING PARTS/

- 37E NAS1104-5 BOLT, MACHINE 3 AN960D416L G-N10U-428 • NUT, SELF-LOCKING, HEXAGON WASHER, FLAT • 6 3

- 37F 89TM10298-1 • FITTING, OUTBOARD HINGE 2 /ATTACHING PARTS/

- 37G NAS1104-11 G-N10U-428 AN960D416 • NUT, SELF-LOCKING; HEXAGON • BOLT, MACHINE • • • • • • WASHER, FLAT

- 38 89T2067-1 SEAL, ELEVATOR TO STABILIZER

- 39 89T2067-3 SEAL, ELEVATOR TO STABILIZER

- 41 - 42 40 8972067-7 8972067-5 89T2067-9 SEAL, ELEVATOR TO STABILIZER SEAL, ELEVATOR TO STABILIZER SEAL, ELEVATOR TO STABILIZER

- 43 89T2067-11 SEAL: ELEVATOR TO STABILIZER

- 44 89T2067-13 • SEAL, ELEVATOR TO STABILIZER 2-54 Changed 1 April 1968