munirabbasi 13 Posted November 27, 2018 Hello World Expertise Aircraft pulled to left during fast taxing.Replaced Steering control valve ,Brakes assembles(04). Rudder ragging. and Nose wheels and Nose mounting toque checked. MLG shock strut servicing and balancing C/Out and MLG tire pressure checked but defect could not troubleshoot (Repeat) Munir Abbasi Home of hercules Pakistan Quote Share this post Link to post Share on other sites
NATOPS1 20 Posted November 27, 2018 I see you have already checked your struts, take a look at the wing fuel balance and wind conditions; also the FCF has specific engine settings FF and torque when checking the NWS for satisfactory operation but it is at much reduced speed. At higher speeds there are a number of factors your crew can look for: roll input (check at different flap settings); ask them to note control surface pressure (rudder and yoke, pitch and aileron) (external forces input) Also have the crew check torque settings on the right engines vs left as higher torque will cause track deviation. Quote Share this post Link to post Share on other sites
Moeed hassan 0 Posted November 27, 2018 2 hours ago, NATOPS1 said: I see you have already checked your struts, take a look at the wing fuel balance and wind conditions; also the FCF has specific engine settings FF and torque when checking the NWS for satisfactory operation but it is at much reduced speed. At higher speeds there are a number of factors your crew can look for: roll input (check at different flap settings); ask them to note control surface pressure (rudder and yoke, pitch and aileron) (external forces input) Also have the crew check torque settings on the right engines vs left as higher torque will cause track deviation. How about anti-skid system???? Quote Share this post Link to post Share on other sites
NATOPS1 20 Posted November 27, 2018 9 minutes ago, Moeed hassan said: How about anti-skid system???? Should not be a factor; you can switch it on (or off) and most likely have the same drift issue as the brakes should be disengaged during the roll. Quote Share this post Link to post Share on other sites
munirabbasi 13 Posted November 28, 2018 8 hours ago, NATOPS1 said: I see you have already checked your struts, take a look at the wing fuel balance and wind conditions; also the FCF has specific engine settings FF and torque when checking the NWS for satisfactory operation but it is at much reduced speed. At higher speeds there are a number of factors your crew can look for: roll input (check at different flap settings); ask them to note control surface pressure (rudder and yoke, pitch and aileron) (external forces input) Also have the crew check torque settings on the right engines vs left as higher torque will cause track deviation. Thanks Best regards Munir Abbasi Home of hercules Pakistan Quote Share this post Link to post Share on other sites
hehe 33 Posted November 28, 2018 (edited) 1. What speed? 2. Does pilot have to use opposite steering wheel inputs to correct? 3. Has neutral/streamline of rudder control surface, trim tab and boostpack been checked? 4. Are the nose tires the same tread pattern and height? if you stick a level across the top of nlg tires, it should be level or match the level of your surface (ground). 5. Has back pressure been checked for brakes? should be no more than 70 psi in return pressure. Anything more can create a dragging brake. Easiest way to find a dragging brake is have crew taxi for about 10 minutes and check temperatures of brakes, they should be similar between left and right side. Brake bleed kit can check back pressure. 6. Have you checked rigging of steering cable/chain 7. Have you checked the NLG scissors and bolts for tightness? Slop in the scissor linkage can create a very uncontrollable NLG steering Edited November 28, 2018 by hehe Quote Share this post Link to post Share on other sites
munirabbasi 13 Posted November 28, 2018 19 minutes ago, hehe said: 1. What speed? 2. Does pilot have to use opposite steering wheel inputs to correct? 3. Has neutral/streamline of rudder control surface, trim tab and boostpack been checked? 4. Are the nose tires the same tread pattern and height? if you stick a level across the top of nlg tires, it should be level or match the level of your surface (ground). 5. Has back pressure been checked for brakes? should be no more than 70 psi in return pressure. Anything more can create a dragging brake. Easiest way to find a dragging brake is have crew taxi for about 10 minutes and check temperatures of brakes, they should be similar between left and right side. Brake bleed kit can check back pressure. 6. Have you checked rigging of steering cable/chain 7. Have you checked the NLG scissors and bolts for tightness? Slop in the scissor linkage can create a very uncontrollable NLG steering Thanks Defect has been rectified Munir Abbasi Home of hercules Pakistan Quote Share this post Link to post Share on other sites
hehe 33 Posted November 28, 2018 9 minutes ago, munirabbasi said: Thanks Defect has been rectified Munir Abbasi Home of hercules Pakistan What was the fix? Quote Share this post Link to post Share on other sites
munirabbasi 13 Posted November 29, 2018 9 hours ago, hehe said: What was the fix? MLG Shock strut balancing problem Best regard Munir Abbasi home hercules Pakistan Quote Share this post Link to post Share on other sites