Go Back   Airline Pilot Central Forums - Find your next job as a Pilot > >
Cargo Part 121 cargo airlines
 

Welcome to Airline Pilot Forums - Connect and get the inside scoop on Airline Companies

If this is your first visit, be sure to check out the FAQ. Join our community today and start interacting with existing members. Registration is fast, simple and absolutely free.


User Tag List

Closed Thread
 
Thread Tools Search this Thread Display Modes
Old 03-14-2019, 12:19 PM   #681  
Moderate Moderator
 
UAL T38 Phlyer's Avatar
 
Joined APC: Mar 2008
Position: Uncertain; Negative RNP
Posts: 4,398
Default

Quote:
Originally Posted by CaptDave View Post
Correct. What if no manual trim activation?
Ahh...you mean manual control column input?

Donít think it will move, nor disengage. Have never tried, and donít really want to test it.
UAL T38 Phlyer is online now  
Old 03-14-2019, 01:10 PM   #682  
Line Holder
 
CaptDave's Avatar
 
Joined APC: Feb 2018
Position: Upright, 32A
Posts: 83
Default

Quote:
Originally Posted by UAL T38 Phlyer View Post
Ahh...you mean manual control column input?

Donít think it will move, nor disengage. Have never tried, and donít really want to test it.
Yes. I messed with it in sim (desktop) with boards up, flaps up, alt selector to 3k coming off of GILLL at 230/7000 on a 270 heading, speed selector 210kts, and LVL CHG. Held back pressure on control column. Autothrottles went max selected thrust rating as speed slowed to 230-210kts region, trim ran full nose down the whole time. As thrust increased, nose went up approx +5degrees. When back pressure released, nose dropped almost instantly to -30. This was with no stick shaker or pusher activation in a desktop sim.

I have zero experience in 76 so Iím just trying to learn and in the course of this, I am 100% confident that it was not intentional.

Last edited by CaptDave; 03-14-2019 at 01:25 PM.
CaptDave is offline  
Old 03-14-2019, 01:38 PM   #683  
Gets Weekends Off
 
Joined APC: Feb 2017
Posts: 1,519
Default

Quote:
Originally Posted by CaptDave View Post
Yes. I messed with it in sim (desktop) with boards up, flaps up, alt selector to 3k coming off of GILLL at 230/7000 on a 270 heading, speed selector 210kts, and LVL CHG. Held back pressure on control column. Autothrottles went max selected thrust rating as speed slowed to 230-210kts region, trim ran full nose down the whole time. As thrust increased, nose went up approx +5degrees. When back pressure released, nose dropped almost instantly to -30. This was with no stick shaker or pusher activation in a desktop sim.

I have zero experience in 76 so Iím just trying to learn and in the course of this, I am 100% confident that it was not intentional.
Why would you be pulling on the yoke with lvl change and autopilot on? AP off would only move the flight directors. Don't fly the 76, but the 744 which is one gen newer in the cockpit. With AP on, it has the yoke. Of course your desktop sim doesn't have force feedback, does it? And I highly doubt it would model the 767 logic in every way.
No Land 3 is offline  
Old 03-14-2019, 02:15 PM   #684  
Diamond Elite Costumer
 
The Dominican's Avatar
 
Joined APC: Dec 2007
Position: 767 captain
Posts: 1,346
Default

Question: if autopilot and autothrottles were engaged, does manual input disengage the A/P?

The A/T will not disengage if you override it, to be able to apply full thrust and have them stay there, the A/T need to be disconnected.

Does the 767 do anything like this? Or can you hold enough back pressure to maintain an altitude without A/P disconnect?

The 76 has weak servos on the A/P system, you can override it and make control inputs, but the A/P will eventually disconnect if the inputs are extreme.
The Dominican is offline  
Old 03-14-2019, 04:05 PM   #685  
Line Holder
 
CaptDave's Avatar
 
Joined APC: Feb 2018
Position: Upright, 32A
Posts: 83
Default

Quote:
Originally Posted by No Land 3 View Post
Why would you be pulling on the yoke with lvl change and autopilot on? AP off would only move the flight directors. Don't fly the 76, but the 744 which is one gen newer in the cockpit. With AP on, it has the yoke. Of course your desktop sim doesn't have force feedback, does it? And I highly doubt it would model the 767 logic in every way.
Correct. No force feedback and system logic is (I guess) decent but I donít have any idea how deep it goes, let alone how deep the physics are simulated, either.
CaptDave is offline  
Old 03-14-2019, 04:09 PM   #686  
Line Holder
 
CaptDave's Avatar
 
Joined APC: Feb 2018
Position: Upright, 32A
Posts: 83
Default

Quote:
Originally Posted by The Dominican View Post
Question: if autopilot and autothrottles were engaged, does manual input disengage the A/P?

The A/T will not disengage if you override it, to be able to apply full thrust and have them stay there, the A/T need to be disconnected.

Does the 767 do anything like this? Or can you hold enough back pressure to maintain an altitude without A/P disconnect?

The 76 has weak servos on the A/P system, you can override it and make control inputs, but the A/P will eventually disconnect if the inputs are extreme.
So it is possible to select a slower speed and altitude and hold manual control input to maintain prior altitude until the aircraft slows? And if autothrottles engaged would advance as the speed slowed to bug?

What about if the flight spoilers were extended?
CaptDave is offline  
Old 03-14-2019, 04:35 PM   #687  
In a land of unicorns
 
Joined APC: Apr 2014
Position: 175 FO
Posts: 1,802
Default

Wait. Are we actually speculating what might have happened based on MS Flight Simulator now?
dera is online now  
Old 03-14-2019, 04:41 PM   #688  
Gets Weekends Off
 
Joined APC: Feb 2017
Posts: 1,519
Default

Quote:
Originally Posted by CaptDave View Post
So it is possible to select a slower speed and altitude and hold manual control input to maintain prior altitude until the aircraft slows?
No, AP moves the yoke. With AP off, the flight director will give cues for what you selected. Never tried to overpower the AP, I always turned it off if needed.
Quote:
And if autothrottles engaged would advance as the speed slowed to bug?
What about if the flight spoilers were extended?
You get an EICAS caution if the spoilers are cracked and thrust is above idle, with AT on or off. (B744)
I'm only guessing Boeing used a PID algorithm for thrust setting and as such would increase thrust if needed to maintain the set point, which it does. (B744)
No Land 3 is offline  
Old 03-14-2019, 04:42 PM   #689  
Diamond Elite Costumer
 
The Dominican's Avatar
 
Joined APC: Dec 2007
Position: 767 captain
Posts: 1,346
Default

Quote:
Originally Posted by CaptDave View Post
So it is possible to select a slower speed and altitude and hold manual control input to maintain prior altitude until the aircraft slows? And if autothrottles engaged would advance as the speed slowed to bug?

What about if the flight spoilers were extended?
Not sure where you are going with this question but it is Monday morning on my Jetlag cycle so it might be me.

The whole autopilot disconnect issue is not much of a factor, it is designed so that it is easy to override and it will remain engaged if the manual correction is small but if you positively apply a few pounds of force in any direction as to significally change pitch or course, the A/P will disengage with an aural and respective master warning and eicas message, just in case it was unintentional.

The A/T only take about 4 pounds of force to override, now I don't really know if it will go to "THR HOLD" if you place it on the fire wall and hold them there as it would if you bring them to idle for example, in 13 years of flying the 76, I haven't come across that scenario.

The spoilers contrary to popular belief, will only retract if you apply power while configured for landing, if the boards are out on a clean configuration and you apply power (Let's say to respond to a TCAS or a GPWS) you will have to manually stow the spoilers, they will not retract automatically. But you will get a master caution with a "Spoilers" message on eicas
The Dominican is offline  
Old 03-14-2019, 04:43 PM   #690  
Gets Weekends Off
 
Joined APC: Feb 2017
Posts: 1,519
Default

Quote:
Originally Posted by dera View Post
Wait. Are we actually speculating what might have happened based on MS Flight Simulator now?
Trying to point out the flaws in doing this.
No Land 3 is offline  
 
 
 

 
Closed Thread
 



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Related Topics
Thread Thread Starter Forum Replies Last Post
Atlas Sues Pilot Group, again CallmeJB Cargo 5 09-26-2017 07:27 PM
757/767 reserve pay Timeoff2fish Cargo 112 03-29-2013 01:36 AM
MEC votes to bring B-Scale to FedEx? steamgauge Cargo 95 03-24-2013 05:55 PM
Houston Express Atlas) to Luanda tailwheel48 Cargo 5 11-04-2011 01:20 PM
Evergreen loses LCF Contract to Atlas EZRider Cargo 2 03-09-2010 06:18 AM


All times are GMT -8. The time now is 02:24 PM.


vBulletin® v3.9.3.5, Copyright ©2000-2019, MH Sub I, LLC dba vBulletin
User Alert System provided by Advanced User Tagging v3.3.0 (Lite) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Website Copyright ©2000 - 2017 MH Sub I, LLC dba Internet Brands

Search Engine Optimization by vBSEO 3.6.1