SAIB CE-09-45

FAA Aircraft Certification Service

SPECIAL AIRWORTHINESS

INFORMATION BULLETIN SAIB: CE-09-45 SUBJ: Leveling & Weighing: Viking Air Limited DHC-2 MKI Gross Weight Increase Modification (STC SA00299NY) Date: July 29, 2009 This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin (SAIB) advises you, owners and operators of Viking Air Limited DHC-2 MKI, of an airworthiness concern, specifically the importance of implementing the recommendations provided in Viking Air Limited Service Letter DHC2-SL-01-001, Issue 1, dated April 24, 2008.

At this time, this airworthiness concern is not considered an unsafe condition that would warrant an airworthiness directive (AD) action under Title 14 of the Code of Federal Regulations (14 CFR part

39).

Background

There have been several reports of DHC-2 MKI aircraft modified to Supplemental Type Certificate (STC) SA00299NY without the installation of a ventral fin (Kit VALBVS1266-1), which is a requirement of the STC. The purpose of this SAIB is to emphasize that a ventral fin and Kenmore Auxiliary Fins (STC SA456NW) are required on the DHC-2 MKI aircraft modified to STC SA00299NY.

• The discrepancy was introduced at revision 4 of Installation Instructions VALBVS1256-27 in Table 3.3, which listed the ventral fin installation kit VAL BVS1266-1 as optional.

• Earlier revisions to Installation Instructions VALBVS1256-27 were approved either by the FAA through the issuance of STC SA00299NY or by Transport Canada, the state of design of the DHC-2 aircraft.

• Revision 4 of Installation Instructions VALBVS1256-27, however, was neither approved by the FAA nor Transport Canada. This unapproved Installation Instructions VALBVS1256-27 at revision 4 was inadvertently obtained and used by some DHC-2 owners and operators, who interpreted the installation of a ventral fin as optional.

• Revision 4 of Installation Instructions VALBVS1256-27 contradicts the top drawing VAL BVS 1256 as referenced in STC SA00299NY which clearly states that the ventral fin is required for the DHC-2 MKI aircraft fitted with EDO 679-4930 or 58-4580 floats.

• Service Letter DHC2-SL-01-001 was issued by Viking Air Limited to communicate this discrepancy that exists between the top drawing VAL BVS 1256 referenced in STC SA00299NY and the Installation Instructions VALBVS1256-27.

• Viking Air Limited has revised Installation Instructions VALBVS1256-27 at revision 6, dated June 10, 2008, Transport Canada approved July 11, 2008, which removed the word “optional” to bring it into alignment with top drawing VAL BVS 1256 and to reduce the possibility of non-conforming configuration in future installations.

• Viking Air Limited will distribute Installation Instructions VALBVS1256-27 at revision 6 to all applicable operators shortly.

2 Recommendations

We recommend that you implement the recommendations provided in Viking Air Limited Service Letter DHC2-SL-01-001 and to attach this Service Letter to your current STC Installation Instructions Manual for reference if you have not received revision 6 of Installation Instructions VALBVS1256-27.

If you have received revision 6 of Installation Instructions VALBVS1256-27, we recommend that you use this revision in place of all previous revisions.

We also stress the importance of adherence to the approved aircraft configurations by the installer and the importance of following operating procedures by pilots and operators.

For Further Information Contact

Pong K. Lee, Aerospace Engineer FAA, Engine & Propeller Directorate NYACO, ANE-171 1600 Stewart Avenue, Suite 410 Westbury, NY 11590 phone: (516) 228-7324 fax: (516) 794-5531 email: pong.k.lee@faa.gov