auto break/spoiler trouble

[Guest]

hello all,i am having trouble with the auto break and auto spoiler systems. i cannot get either of them to function upon touch down. i know the spoilers dont work without autobreaking armed so i assume getting the breaks to work will solve both problems. has anyone else encounterd this trouble? anybody have a clue as to what im doing wrong?thanks thomas

[Jet Tech 31]

ThomasWhat setting are you using for Autobrakes (1,2, Max)?So far I haven't had any trouble setting mine at 2 for landing and the AutoSpeedbrrake system has activated once the nosewheel touchs down. Can you give a detailed account of how you are setting up the A/C for landing.Paul:-cool

[Guest]

hello Paul,i am setting up the A/C for an ILS and let it auto land with flaps 30 auto-throttle off and at ilde power. i have tried the auto breaks at each setting (1-thru-max) and position the speedbreak leaver to the arm position, and neither system has worked at all. further the auto break selector does not return to off as is should at the end of the landing role so i assume i am missing a nessesary step in arming the system, but i cant find it in the manual.thanks for any help you can provideThomas

[Jet Tech 31]

Thomas,Sounds like your set up right, but the Autobrakes shouldn't disarm after landing til you depress the Brake Pedals or Disarm the system. Am I correct in assuming that you are getting no deceleration using the Autobrakes or is it just not feel noticeable. I have noticed that the Autobrakes on the 757 felt weak however I have been landing fairly heavy (208,000) so I expected that. When I observed the Airpspeed indicator with Autobrakes on and no Reverse Thrust, The A/C did slow from 135kts to 0 in about 7,000 ft of Runway. Also, you didn't say whether or not you were using Reverse Thrust at all. I have found that with Autobrakes 2 and Reverse Thrust I can get the A/C stopped in well under 4,000 ft. This thing has REALLY GOOD REVERSERS! As far the Auto speedbrakes go, System should actuate once the Mains touchdown but I believe the PMDG model actuates when the nose gear touches down, You should be able to to hear the Auto Speedbrake Actuator operate in the Sound Effects. I will try it again tonight to verify my Speedbrakes are actually deploying, I assumed they were since I heard the Actuator move. Good LuckPaul :-cool