Issued Revised Page No. Rev.

DAY MONTH YEAR DAY MONTH YEAR 1 of 3 A 16 09 2013 ALLSTAR PZL GLIDER Sp. z o. o. ul. Cieszynska 325, 43-300 Bielsko-Biala, Poland

tel.: +48 33 812 50 26

fax: +48 33 812 3739 techsupport@szd.com.pl www.szd.com.pl 

# SERVICE BULLETIN

Allstar PZL Glider considers compliance mandatory



## BE-062/SZD-50-3/2013 „PUCHACZ”

DATE: September 16, 2013

SUBJECT: Inspection of torque tube in air-brake control syst em

MODELS AFFECTED: All S/N of SZD-50-3 „Puchacz”

TIME OF COMPLIANCE: After receiving the SB

NOTE Incomplete review of all the information in this do cument can cause errors. Please read the entire SB to make sure you have a complete understanding of the requirements.

1. BASEGROUND OF THE SB:

The mandatory bulletin BE-052/SZD-50-3/2003 „PUCHAC Z”, issued in 2003, did not enclose the information about repetative inspections of torque tube air-bra ke control system in the fuselage, as well as did n ot cover the information about processing method after exchangin g of infected tube with the new one, equipped with reinforced

corner. This SB replaces the BE-052/SZD-50-3/2003 „PUCHACZ” and – additionally – specifies the above informati on.

Up to 2003, during the flights, while operating the airbrakes, a few incidents of the torque-tube brea k-off from the lever located in fuselage, had been experienced. Th e damages occured at the welded joint between the t ube and the lever, which did not allow to retract the airbrake. Possible reason could be a fatigue in the area of f requent occurrence of striking load, exceeding recu rrently the

established value or/and corrosion detected inside the area of opened tube.

2. COMPLIANCE WITH SB REQUIREMENTS

(a) Conditions of inspection:

1. for the gliders still equipped with the old version of torque tube, with or without reinforced corner, do as follows (see Sketch 1):

• annually or during „100-hrs” inspection, in case of whichever occurrs first, inspect the welded joint of airbrake torque tube, acc. to the description speci fied in item 2(b) of this SB;

2. for the gliders with the new type of torque tube wi th reinforced corners (see Sketch 2), i.e. the glid ers from S/N 503.A.03.001 and up as well as others with the new type torque tube (see Sketch 2) do as follows:

• annually or during „100-hrs” inspection, whichever occurrs first, check visually (disasembling of the tube from the fuselage is not necessary) the welded join t of the torque tube. Inspection of the areas parti ally obscured by the reinforcing plates is not required.

• during „1000-hrs” inspection check the welded joint of torque tube as described in 2(b) of this SB.ALLSTAR PZL GLIDER Sp. z o.o. SERVICE BULLETIN BE-062/SZD-50-3/2013 „PUCHACZ”

Issued Revised Page No. Rev.

DAY MONTH YEAR DAY MONTH YEAR 2 of 3 A 16 09 2013 (b) Inspection procedure:

1. Dissassemble the glider.

2. Remove the torque tube of airbrake control system ( Fig. 9, item 8 – TSM, issue III/Sept. 1980 or Fig. 8/2, item 8 – TSM, issue I/JAR-22/Nov. 1994).

To do so, proceed as follows:

• remove the rear seat panel;

• remove the side and rear wall of baggage compartmen t. The side wall is fastened in front with 2 screws to main frame, and the rear wall with 2 screws to bagg age compartment wall;

• disconnect the torque tube from airbrake push-rod ( Fig. 9, item 9 – TSM, issue III/Sept. 1980 or Fig. 8/2, item 9 – TSM, issue I/JAR-22/Nov. 1994);

• remove the end of torque tube on lever’s side (Fig. 2, item 6 – TSM, issue III/Sept. 1980 or Fig. 1/2, item 6 – TSM, issue I/JAR-22/Nov. 1994);

• take the torque tube out of the fuselage, raising i t up and forward. 3. Check the condition of torque tube in the area o f welded joint with lever (as well as the additiona l reinforcing plates) – see the Sketch 1 or Sketch 2, dependently on the existing solution:

• Check with the 3 x min. magnifying glass for painti g cracks and tube’s condition in the area of welded joint (also reinforcing plates), which could be an eviden ce of joint and/or tube cracking. If found the crac ks of paint, remove coating and check the surface of tube . Fluorescent Penetrant Inspection (FPI) inspection may be done as an optional.

• Check the torque tube for permanent distortion of c ylindrical tube’s shape.

a)

b)

Sketch 1 – Previous version of airbrake torque tube : a) without reinforcement; b) with a single reinforc ement

inspection area

inspection area additional reinforcementALLSTAR PZL GLIDER Sp. z o.o. SERVICE BULLETIN BE-062/SZD-50-3/2013 „PUCHACZ”

Issued Revised Page No. Rev.

DAY MONTH YEAR DAY MONTH YEAR 3 of 3 A 16 09 2013

Sketch 2 – New version of reinforced torque tube

4. Check for evidence of corrosion of the inside welde d joint area of torque tube.

( c) Post-inspection procedure:

1. Cracks, permanent distortion of torque tube as well as corrosion pit on tube’s inner side in the area of welded joint are not acceptable. In case of one of the def ects listed above – replace the tube with the new o ne, purchased

from Allstar PZL Glider – item no. 503.64.30.00A. T he old tube may be released into service if no one of

described defects exists.

2. Slight, uniform corrosive deposit should be removed with fine abrasive sand paper (grid 600 at min). If no corrosive pits are present on the surface, pr event inner area of the tube with anticorrosive age nt (for ex. Fluidol) and release the tube into service . However, replacement the tube with the new one co uld be

reccomended.

- END - additional reinforcement inspection area

areas partially obscured by reinforcement