Landing Gear

1 FAA Aviation Safety SPECIAL AIRWORTHINESS INFORMATION BULLETIN SUBJ: Landing Gear SAIB: NM-15-24 Date: September 29, 2015 This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin is to alert owners, operators, and maintenance technicians of the potential for damage to the hydraulic servo block (shuttle valve) mounted to the retraction jack of the main landing gear (MLG) due to debris from tire tread separation during takeoff, on the following Beechcraft Corporation airplane models:

DH.125 Series 1A; HS.125 Series 1B; DH.125 Series 1A-522; HS.125 Series 1B-522; DH.125 Series 1A/R-522; HS.125 Series 1B/R-522; DH.125 Series 1A/S-522; HS.125 Series 1B/S-522; DH.125 Series 3A; HS.125 Series 3B; DH.125 Series 3A/R; HS.125 Series 3B/R; DH.125 Series 3A/RA; HS.125 Series 3B/RA; HS.125 Series 3B/RB; HS.125 Series 3B/RC; HS.125 Series F3B; HS.125 Series F3B/RA; BH.125 Series 400A; DH.125 Series 400A; HS.125 Series 400A; HS.125 Series 400B; HS.125 Series 400B/1; HS.125 Series 401B; HS.125 Series 403A(C); HS.125 Series 403B; HS.125 Series F400B; HS.125 Series F403B; BH.125 Series 600A; HS. 125 Series 600A; HS.125 Series 600B; HS.125 Series 600B/1; HS.125 Series 600B/2; HS.125 Series 600B/3; HS.125 Series F600B; HS.125 Series 700A; HS.125 Series 700B; BAe.125 Series 800A; BAe.125 Series 800A (C-29A); BAe.125 Series 800A (U-125); BAe.125 Series 800B; BAe.125 Series 1000A; BAe.125 Series 1000B; Hawker 1000 and Hawker 800 series airplanes.

Hawker 800 (U-125A) series airplanes, up to and including serial number 258797; and Hawker 800XP and 850XP series airplanes, up to and including serial number 258770.

At this time, the airworthiness concern is not an unsafe condition that would warrant airworthiness directive (AD) action under Title 14 of the Code of Federal Regulations (14 CFR) part 39.

Background

We received reports of three incidents of tire tread separation during takeoff, in which pieces of the tire struck the retraction jack of the MLG and resulted in separation of the hydraulic servo block (shuttle valve) from the cylinder, and loss of both normal and emergency hydraulic pressure on certain Hawker airplanes. The servo block connects to both the normal and emergency hydraulic systems. Separation of the servo block from its mount on the retraction jack can cause loss of fluid from both systems, and in all three incidents, the servo block separated from its mounting. This separation results in loss of the ability to lower the landing gear and the flaps. In one incident the gear-up, flaps-up landing resulted in a fire and compromised fuel tank integrity; however, no injuries were reported for any of these incidents.

Beechcraft Corporation issued Service Bulletin 32-3777, dated October 2006, to provide operators with procedures for replacing the MLG jacks with an improved hydraulic servo block (shuttle valve) mounting for better resistance to tire debris. This service bulletin was issued eight years prior to the latest incident, but had not yet been incorporated on this airplane model.

2 Recommendations

The FAA recommends that owners, operators, and maintenance personnel of the affected airplanes follow the procedures outlined in Beechcraft Corporation Service Bulletin 32-3777, dated October 2006, at the earliest opportunity.

For Further Information Contact

Paul DeVore, Senior Aerospace Engineer, Mechanical Systems and Propulsion Branch, ACE-116W, Wichita Aircraft Certification Office, 1801 Airport Road, Wichita, Kansas 67209; phone: 316-946-4142; fax: 316-946-4107; email: [email protected].

For Related Service Information Contact

Beechcraft Corporation, TMDC, P.O. Box 85, Wichita, KS 67201-0085; phone: 800-796-2665 or 316-676-8238; fax 316-671-2540; email [email protected]; Internet http://pubs.beechcraft.com.