YAK-52 SERVICE BULLETINS

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YAK-52 SERVICE BULLETINS A full Yakovlev Design Bureau list Initially, there was no difference between the Service Bulletins as introduced by the Yakovlev Design Bureau and Airworthiness Directives as approved and made mandatory by the Certification Body, in case of Yak-52, the Soviet Air Force. Both were elements of the same logical chain, and all bulletins were automatically implemented with the whole fleet concerned. To date during the certified factory overhaul (provided today only by Shakhty Overhaul Plant), the aircraft SB status is checked against the FULL list. N° Summary Serial N°s concerned 1DK Bonding of the elevator and the engine lower cowling 780102 - 790404 2DK Replacing of the soldered oil tank by the welded one 780102, 790105, 790203, 790406 3R Improvement of the system of the carburetor heating 780103 – 811215 4R Improvement of cooling of the compressor 780103 – 800815 6DK New KP-4716 starter’s solenoid 790105 – 800605 7DK Removal of the switch of the generator command selector between the front and the rear cockpits 780102 – 800815 8R Strengthening of the fix of the brake handle 780102 – 801103 9DK Strengthening of the fin skin 780102 – 811212 10R Enhancement of engine cooling efficiency 780103 – 800815 11E New life time for fuel tanks 800802 – 801006 12R Improvement of pneumatic system 780102 – 800815 13BD Modification of the current inlet 780102 – 844415 15E New life time for the propeller all 17DM Replacement of the over-voltage switch AZP-1MB by AZP-A2 780102, 780103 790105 – 811707 18DA (and 28BA) Strengthening of the fin’s base. Riveting of the elevator’s counter weight instead of bolting 780102 – 833805 19R (and 52R) Introduction of the battery 12-ASAM-23 instead of “Verli” 780102 – 822714 21E New life time for the engine mount ring 780102 – 821915 28BA Addition to N°18DA 29BE Heavy spar and new wing attachments introduced during the manufacture 30BD New pitch lever 526500-36 780103 – 844415 32BU New switchboard bus 780102 – 833715 34BD New intake coupling of the fuel pump 780102 – 844915 36BD New bracket of the R2 revolutions regulator 780102 – 855707 © Aeroconcept Trading, 2002 -2- 37BD New aileron suspension brackets 780102 – 855615 38R Modification of the main undercarriage spindles 780102 – 855815 39DK New trim tab wheels in both cabins 780102 – 844915 40DK New markings of the Pitot system pipes 780102 – 855315 41R Removal of the pneumatic bloc AD-50 and redesign of pneumatic system elements on the frame N° 0 780103 – 855215 42DK Enhanced protection of the electric wiring near the fix of AZRGK-10 switch at the frame N°2, right side 780102 – 855607 44R New rudder trim tab 780102 – 856105 45DK Strengthening of the cooling pipe of the compressor and of its fix to the engine mount 780102 – 855815 47R New fastening clamp of the oil system vent tank 780102 – 855815 48R New filter box in the carburetor air intake 780102 – 855915 49R Addition of the third support of the fuel tanks 780102 – 856215 52R Additional to N°19R 53BU New design of control sticks in front and rear cabins New rear command axle bearing bracket 780102 – 889715 54R Introduction of locking washers in the controls 780102 – 866415, 866501 – 888615 55BU New wires from the P-1 sensor to the cylinder temperature indicator 780102 – 867315 57DK New exhaust collector and cockpit heating 780103 – 866515; 866601 – 867315 58BD Improvement of the fastening of the engine commands’ stiffening 780102 – 866415 59R Strengthening of the wing attachment fittings 780102 – 866415 60R Introduction of the heavy main spar 780102 – 866415 62DK Improvement of the fastening of the aileron counter weight 780102 – 866915 66R (and 88BD) Introduction of 8,5 mm bolts of the wing fastening on the frames NN° 3 and 8 780102 – 866515 67R Introduction of the clamp fastening of the right intake pipe to the right nozzle of the exhaust collector 780102 – 866915 68BD Braking of the handle of the pedal adjusting screw 780102 – 866115 69BU Strengthening of the support of the PT-200C transformer 780102 – 877515 70BU Improvement of the fastening of the rudder counter weight 780102 – 877615 71BD New oil draining tank 780102 – 877615 72BD Check of the hinge in flaps controls 780102 – 877315 74BU Installation of screw brackets limiting the oil cooler and chatter control levers in the front cockpit 780102 – 834015 75BU Strengthened aileron hinge bracket and rib N° 7 780102 – 877515 © Aeroconcept Trading, 2002 -3- 76BD New ball joints of the engine control system 780103 – 877503 78BD New oil filter assembly 780102 – 888715 80BD (add. to 59R) Strengthening of the rear web of the right wing between the ribs NN° 2 et 2A 780102 – 888915 81BD Strengthening of the support of the magnetic compass and of the G-meter in the front cockpit. 780103 – 8910015 82BD Strengthened rudder hinge bracket 780102 – 889015 83BD Strengthening of the rear ribs of the elevator 780102 – 888915 84BD Protection housing of the tension regulator R27 780102 – 889009 85BU Improvement of the tightness of the exits of the flap cylinder rods 780102 – 888713 87BD Strengthening the rear spars 780102 – 866415 88BD Same as 66R 780102 – 888915 89BD Strengthening of the fuselage spar 780102 – 889115 90BD Removal of the artificial horizons and of the main directional gyro for aerobatic use At operator’s discretion 92BD Strengthening of the aileron’s rib N° 1 780102 – 889301 93BD Elimination of friction between the elevator’s counter weight and the rib N° 3 780102 – 889015 94BU Introduction of the Ø 1.2 mm chocks instead of Ø 0.5 mm in the undercarriage extension system 780102 – 889009 96BE Increasing time before the first overhaul to 600 hours 97BU New harness with the pin lock 844701 – 9010815 99BD Strengthening of the cooling pipes of the generator and of the compressor 780102 – 889915 100BD Wire locking of the nut of fastening of the cowl flaps ring 780102 – 899515