Applicability: SAAB 5F340A-004 through -159and SAAB 340B-160 through -439.

Effective date: February 25, 1999

Compliance: Required as indicated in SAD 1-110R2.

LUFTFARTSVERKET Aviation Safety Department SWEDISH AIRWORTHINESS DIRECTIVES (SAD)
SAD No 1-110R2 Cancels 1-110R1
Section 1. Swedish Manufactured Aeronautical Products

AIRCRAFT TYPE: SAAB SF 340A and SAAB 340B

SERIAL No’s AFFECTED: SAAB 5F340A-004 through -159and SAAB 340B-160 through -439. Note: Effectivity changed

SUBJECT: Stabilizers - Horizontal Stabilizers - Inspection of Holes

BACKGROUND: During simulated flight testing in the "Full Scale Fatigue Test Rig" fatigue cracks have been observed in the forward spar of the Horizontal Stabilizer.

The observed cracks are located at the intersection between the rear fuselage and the forward upper spar cap. The starting point for the cracks is considered to be in the upper part of the web of the forward spar.

Detailed and special detailed inspections (NDT) in the actual area are required in order to ascertain continued airworthiness.

The purpose is also to collect data for a continued investigation regarding the crack.

Note: A mandatory Service Bulletin SB 340-55-034 is released describing actions to improve fatigue life.

REFERENCE DOCUMENTS: Saab AB Service Bulletin SAAB 340-55-033 Revision 04 dated 1 December,1998.

ACTIONS: Perform actions described in Saab AB Service Bulletin SAAB 340-55-033 Revision 04 dated 1 December,1998 or later revision.

If cracks are detected, contact Saab AB for actions before further flight.

COMPLIANCE TIME:

For A/C with less than 20000 flights, NDT inspection to be performed, within 22000 flights.

For A/C with 20000 thru 22000 flights, NTD inspection to be performed within 2000 flights from 21 April,1997.

For A/C with 22000 flights thru 30000 flights, detailed inspection to be performed within 800 flights from effective date of this SAD and NDT inspection within 2000 flights from 21 April,1997.

For A/C with 30000 flights and more, detailed inspection to be performed within 400 flights from effective date of this SAD and NDT inspection within 1200 flights from 21 April,1997.

Repetitive NDT inspection to be performed every 12000 flights for all A/C 004 through 159.

For A/C with less than 10000 flights, NTD inspection to be performed, within 12000 flights.

For A/C with 10000 thru 12000 flights, NDT inspection to be performed, within 2000 flights from 21 April,1997.

For A/C with 12000 through 16000 flights, detailed inspection to be performed within 800 flights from effective date of this SAD and NDT inspection within 2000 flights from 21 April,1997.

For A/C with 16000 flights and more, detailed inspection to be performed within 400 flights from effective date of this SAD and NDT inspection within 1200 flights from 21 April,1997.

Repetitive NDT inspection to be performed every 6000 flights for all A/C 160 through 439.

EFFECTIVE DATE: 7 December,1998