SPECIAL AIRWORTHINESS INFORMATION BULLETIN
Aircraft Certification Service
Washington, DC
U.S. Department of Transportation
Federal Aviation Administration
CE-20-08 R1

August 10, 2020

This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin is to alert owners, operators, maintenance technicians, and inspectors of an airworthiness concern on Pilatus Flugzeugwerke Models P3-03 and P3-05 airplanes, all serial numbers (S/N). Specifically, the concern is the possibility of stress corrosion cracking on the fuselage to horizontal tail fittings that may have been caused by damage of these fittings during maintenance work by using a center punch tool and a combination of the relatively high fleet age and other aging effects. If this condition is left uncorrected, the structural integrity of the airplane could be affected.

Note: Some of the airplanes listed in the FAA aircraft registry referenced S/Ns with A-8xx are wrong. The A-8xx references are the old military aircraft registrations and not the S/Ns of the airframes.

These airplanes are not type certificated in the United States and, therefore, the condition is not addressed by FAA Airworthiness Directive (AD) action. However, these airplanes could be operating in the United States with an experimental airworthiness certificate or other means.

Background

The Swiss Federal Office of Civil Aviation (FOCA) has issue FOCA Airworthiness Directive (AD) HB-2020-001 dated January 8, 2020 on Pilatus Flugzeugwerke Models P3-03 and P3-05 airplanes, all serial numbers (S/N), to require the following in Switzerland (Original Issue of SAIB CE-20-08 dated April 21, 2020):
 The Swiss Federal Office of Civil Aviation (FOCA) has issue FOCA Airworthiness Directive (AD) HB-2020-006 dated July 21, 2020 that supersedes FOCA AD HB-2020-001 for the Pilatus Flugzeugwerke Models P3-03 and P3-05 airplanes, all serial numbers (S/N). The new FOCA AD maintains the initial inspection requirements for damage caused by center punch tool, but removes the repetitive eddy current inspections and requires either replacing the affected part(s) with serviceable part(s) or repairing the affected part(s) with approved repair solution before further flight.

The reason for the new FOCA AD HB-2020-006:

Since that AD HB-2020-001 was issued, FOCA received feedback after several Pilatus P3 airplanes were inspected. The evaluations of the feedback revealed that airplanes were found with no damages or if damages was found, the necessary corrective action may differ significantly to each damaged airplane. Therefore the repetitive inspection requirement if no crack on the affected part was found was removed in the new FOCA AD HB-2020-006. If damage of the fuselage to horizontal tail fitting was found the damaged parts must be replaced or repaired with an approved procedure.

The actions and compliance times for the FOCA AD HB-2020-006 are as follows:

Within the next 100 Flight Hours (FH) or at the next annual inspection after January 22, 2020 (the effective date of the FOCA AD HB-2020-001), whichever occurs first, remove the horizontal stabilizer from the fuselage in accordance with Technisches Reglement der Fliegertruppe 56.199d for Pilatus P3-03/05 aircraft, Band 10, chapter 13.12, section 5:

Inspection:
(1) Perform a visual inspection for damage caused by using a center punch tool. No signs of damage caused by using a center punch tool are permitted.
(2) If during the inspection required by paragraph (1) of the FOCA AD any fuselage to horizontal tail fittings with no signs of damage caused by using a center punch tool are found, no further action is necessary.

Note 1:
If the required actions under paragraph (1) and (2) of this AD were already performed under FOCA AD HB-2020-001 and no affected parts are found, no further action is necessary under FOCA AD HB-2020-006.

New corrective actions if affected parts are found:
If affected parts are found during the inspection of paragraph (1) and (2) either by the execution of FOCA AD HB-2020-001 or this new AD, accomplish the following corrective actions:

Corrective Action(s):
(3) If during the inspection required by paragraph (1) of this AD any fuselage to horizontal tail fittings with signs of damage caused by using a center punch tool are found, before next flight, replace the fitting with a serviceable part or repair the fitting in accordance with an approved repair solution.

Parts installation:
(4) Do not install an affected part on any airplane, as required by paragraph (4.1) or (4.2) of the FOCA AD HB-2020-006, as applicable:
(4.1) For Group 1 airplanes (airplanes with affected part installed): After the replacement or repair of each affected part as required by paragraph (3) of FOCA AD HB-2020-006.
(4.2) For Group 2 airplanes (airplanes without affected part installed): From the effective date of FOCA AD HB-2020-006.

Recommendations

For Pilatus Flugzeugwerke Models P3-03 and P3-05 airplanes, we recommend adherence to the inspections and corrections per the FOCA AD HB-2020-006 and the corresponding service information Technisches Reglement der Fliegertruppe 56.199d for Pilatus P3-03/05 aircraft, Band 10, chapter 13.12, section 5. A copy of the service information along with a copy of the FOCA AD and better pictures of the area of concern are available on the FOCA website at:

https://www.bazl.admin.ch/bazl/en/home/specialists/aircraft/airworthiness-directives--ad-/lta- schweizer-produkte/p3.html

For Further Information Contact

Doug Rudolph, Aerospace Engineer Federal Aviation Administration, Small Airplane Standard Branch, AIR-692, 901 Locust Street, Room 301, Kansas City, MO; phone: (816) 329-4059; fax: (816) 329-4090; e-mail: doug.rudolph@faa.gov.

For Related Service Information Contact

For further information on the FOCA AD contact: FEDERAL OFFICE OF CIVIL AVIATION (FOCA) Design and Production (STEH) CH-3003 Bern, Switzerland E-mail: airdir@bazl.admin.ch
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