SERVICE BULLETIN TRANSMITTAL SHEET

DHC-3 WING BOX INSPECTION HOLES IN THE LOWER WING SKIN

Service Bulletin No.: 3-STC(03-50)-001 Date of Original Issue: 03-July-2013

Revision No: NC Date of Issue: 03-July-2013

NOTE: This Service Bulletin is associated with Viking Service Bulletin V3/0002.

Viking has received SDRs related to cracking of the DHC-3 wing upper skin corrugations as well as 

cracks in the main spar lower cap. The intent of this Service Bulletin is to provide proper access to 

carry out Viking DHC-3 Service Bulletin V3/0002 Rev B, which is intended to detect and repair these 

cracks and to obtain as much information as possible from operators, to evaluate the overall condition 

of the fleet, to assess if further action is required.

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03 July 2013 Service Bulletin 3-STC(03-50)-001
1959 De Havilland Way 

Sidney, B.C. Canada 

V8L 5V5 

Tel: (250) 656 - 7227 

SERVICE BULLETIN

ATA SYSTEM: 5700 NUMBER: 3-STC(03-50)-001

(Ref. SB V3/0002)

SUBJECT: DHC-3 Wing Box Inspection Holes in the Lower Wing Skin

I. PLANNING INFORMATION

A. Effectivity

Aircraft Affected: DHC-3 Aircraft with only Viking Air STC-03-50 (9000lb Gross Weight 

Kit) installed.

NOTE1: Although this Service Bulletin references the Canadian STC number for 

the Viking Air 9000lb Gross Weight Kit, this document also applies to DHC3 aircraft with the US STC (SA02009NY).

NOTE 2: The intent of this Service Bulletin is to support the incorporation of Viking

SB V3/0002 Rev B wing inspection for aircraft with Viking STC-03-50 only. 

It is not intended to be used on wing with other STCs.

B. Reason

This Service Bulletin was created to inform operators of DHC-3 aircraft with the Viking 

Air 9000lb Gross Weight Kit installed, Viking MOD KIT C3MK1004 – Wing Inspection 

Access Holes is compatible with their aircraft. This MOD is intended for access 

through the wing lower skin to assist in the internal wing box inspection required, in 

accordance with Viking SB V3/0002, Revision B.

C. Description 

This document is intended to be used with SB V3/0002 Revision B, which provides 

operators with a comprehensive inspection program required for DHC-3 wings.

D. Compliance 

Operators shall follow the Compliance times as listed in SB V3/0002 Revision B.

DHC-3

OTTER

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SERVICE BULLETIN 3-STC(03-50)-001

E. Approval

The technical content of this Service Bulletin has been approved under the authority 

of Transport Canada Civil Aviation (TCCA).

F. Labor Time Required

There is no direct labor associated with this Service Bulletin. Reference Service 

Bulletin V3/0002 for labor estimate.

G. Weight and Balance 

Refer to SB V3/0002 Revision B.

H. Electrical Load Data 

Not affected. 

I. Publications Affected 

None.

J. References 

This Service Bulletin is associated with SB V3/0002 - DHC-3 COMPLETE WING 

BOX INSPECTION – BORESCOPE AND VISUAL. For more information please 

contact:

Viking Air Limited Technical Support

1959 De Havilland Way

Sidney, British Columbia

V8L 5V5

technical.support@vikingair.com

FAX: 250-656-0673

Telephone Numbers:

Regional: 250-656-7227

North America: 1-800-663-8444

International: 1-800-6727-6727

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II. ACCOMPLISHMENT INSTRUCTIONS

A. INTRODUCTION OF NEW ACCESS HOLES IN LOWER WING SKIN

1. Complete all instructions as listed in Viking Service Bulletin SB V3/0002 Revision B 

except that all mention to MOD KIT 3/1002 must be read as MOD KIT 3/1004 which 

is the MOD compatible with STC-03-50 (SA02009NY).

B. RECORDING

1. Make an entry in the aircraft flight log book upon completion of the instructions (e.g., 

Incorporation of access holes done in accordance with Sec. II A) would be entered 

as: “incorporation of SB 3-STC(03-50)-001 DHC-3 for MOD KIT C3MK1004 access 

holes COMPLETED IN ACCORDANCE WITH SECTION II.A AT XX,XXX WING 

FLIGHT HOURS FOR WING S/N XXX.”

III. MATERIAL INFORMATION AND TOOLING 

A. Material

• None

B. Tooling – Price and Availability 

• None

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