SAIB CE-04-59

SPECIAL

AIRWORTHINESS

INFORMATION

BULLETIN

Aircraft Certification Service Washington, DC

U.S. Department of Transportation Federal Aviation Administration

CE-04-59 March 30, 2004 www.faa.gov/certification/aircraft This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin alerts you, owners and operators of a LET AERONAUTICAL WORKS Model L-13 Blanik glider, that LETECKÉ ZÁVODY a.s. has issued Mandatory Bulletin No. L13/103a to address the installation of a new handle for the flap control lever. This manufacturer’s bulletin specifies the installation of a new handle over the existing handle within three (3) months after receiving this manufacturer’s notice.

Background

The FAA has received Safety Recommendation No. 02.009 (issued October 18, 2001), which addresses an accident involving the use of the L-13 flight control handles. The issue involved a pilot who confused the flap handle with the air brake handle during operation. These two (2) handles have very similar ergonomics and are located in close proximity of each other when in the stowed position.

Numerous occurrences have been acknowledged from the gliding community concerning this issue.

LET has responded by implementing a change to the existing flap control lever via a service bulletin.

Recommendation

We recommend that registered owners of LET L-13 gliders seriously consider accomplishing the actions of LETECKÉ ZÁVODY Bulletin No. L13/103a, per manufacturer’s requirements. We have attached their bulletin.

For Further Information Contact

Gregory Davison, Aerospace Engineer, FAA Small Airplane Directorate, Room 301, 901 Locust, Kansas City, Missouri 64106; phone: (816) 329-4130; fax: (816) 329-4090; email:

gregory.davison@faa.gov

LETECKÉ ZÁVODY a.s. Kunovice 686 04; phone: 42-572-817-650; fax: 42-572-817-653; or:

Blanik America, Inc., P.O. Box 1124, Wenatchee, WA 98807-1124; phone: (509) 884-8305; fax:

(509) 884-9198

LET LZ LETECKÉ ZÁVODY

MANDATORY BULLETIN MB No.: L13/103a Concerning: All L-13 gliders under the US register Reason: Installation of new handles of flaps control levers to enlarge the difference between the flaps and air-brakes levers handles To be carried out not later than: Three (3) months after the bulletin receiving To be carried out by: Operator Costs covered by: Operator Necessary material to be supplied by: LETECKÉ ZÁVODY a.s. Kunovice Czech Republic based on a customer order Bulletin becomes effective: On the day of CAA CZ approval Sheets: 2 Manufacturer Engineering data contained in this Bulletin is CAA Approved Date:

Q 0501 Pl.2/C Leteckè závody a.s. Kunovice 686 04, tel.: 572 817 650, fax: 572817653, e-mail: ots@let. cz 2

A. WORK PROCEDURE

• For easier assembly, apply slightly a saponaceous or lubrication oil on the inner part of the new handle

• By shift or turn and shift motion install the new handle on the handle of the flaps control lever in front and rear cockpit B. MATERIAL REQUIRED FOR MODIFICATION OF ONE SAILPLANE

• HANDLE A790349a 2 pcs per sailplane C. ILLUSTRATIONS Not necessary D. DOCUMENTATION REQUIRED Not necessary E. TOOLS REQUIRED Not necessary F. SPARE PARTS IN OPERATION Not affected G. SAILPLANE MASS Not affected H. RECORD IN LOGBOOK AFTER BULLETIN IMPLEMENTATION Installation of handles of flaps control levers performed according to the Bull.

L13/103a.

Date: Performed by: .

(legible signature of verification engineer)

ACCOMPANYING DOCUMENTATION Not affected 3