Go Back  PPRuNe Forums > Flight Deck Forums > Tech Log
Reload this Page >

Airbus reporting CI

Tech Log The very best in practical technical discussion on the web

Airbus reporting CI

Old 28th Jul 2019, 23:10
  #21 (permalink)  
 
Join Date: Oct 2015
Location: Millioke
Posts: 168
Originally Posted by Check Airman View Post
A few guys at my airline are paranoid about changing the CI. They'd rather fly in selected speed for 4 hours. I change it when appropriate. Never heard a peep.

Our SOP allows us to manage CI (16-120) to achieve an on time arrival. CI 0 is used if fuel is the over riding concern. Airbus reminds us to “SET MANAGED SPEED” at every phase of flight change so operating in SEL seems odd coming from a training department.

If one is crossing the pond at a fixed MACH I get flying selected. In every other situation I don’t understand some companies resistance to employing the aircraft a designed. I guess that makes the world interesting.

CaptainMongo is offline  
Old 29th Jul 2019, 04:56
  #22 (permalink)  
 
Join Date: Mar 2006
Location: USA
Posts: 1,349
Originally Posted by Vessbot View Post
From an outsider's perspective (non Airbus and non autothrottle pilot), I'd guess "taboo." That uncomfortable feeling in the back of your mind that doing the thing, in light of how it's not usually done, especially with someone else watching, feels wrong to do as if it's against a rule even though no such rule exists (nor is it dictated by any considered prudence.... or even where prudence would say that it's actively counterproductive)

Kind of like how people will leave the FD up when they obviously have no intention of following it, (and there is no FD mode that will make it track what they intend to do) yet it just... feels wrong to turn off.
My first transport jet had no AT, so turning it off isn't a big deal. In terms of the FD, I worry about the guys who can't shoot a visual with the FD off.
Check Airman is offline  
Old 29th Jul 2019, 05:46
  #23 (permalink)  
 
Join Date: Jun 2007
Location: Wanderlust
Posts: 2,237
. I just think that the technique mentioned above seems like it'd be a lot easier if you just turned off the AT.
I also disagree with the earlier poster who said that VS is smoother than CLB. That may be a holdover from another type, but my understanding from the latest Safety First article is that the airspeed info is filtered before being sent to the AP, so the pitch response is nice and smooth, even in bumpy air.
Check airman, as you can see one person feels VS is better than Climb, you feel it will be even better with ATHR off. It doesn't end there. The tinkering will carry on. ​​​But manufacturer who designed the aircraft have more qualified people what do they feel is the most important. If you don't like what they want you to do tell them. As you mentioned about filtering of speed there was no way of knowing that for a line pilot unless the manufacturer told them. So line pilots should follow recommended procedures and not develop their own. Definitely not in Airbus. If you feel something doesn't work or you have better idea than Airbus discuss with them. Toulouse oversees everything from Argentina to Korea(longer way). When someone wants to do it differently in Korea may be someone already had an incident doing it in Argentina. So let them tell you. Every tinkering may not be as dangerous as QZ8501 but better be safe than sorry. There are climb speeds no climb vertical speeds. VS can definitely be used as a short term intervention for whatever but not as a standard practice.
vilas is online now  
Old 29th Jul 2019, 06:51
  #24 (permalink)  
 
Join Date: Mar 2012
Location: Having a margarita on the beach
Age: 100
Posts: 1,293
The amount of home made procedures You can read on this thread is quite scary.
sonicbum is online now  
Old 29th Jul 2019, 08:31
  #25 (permalink)  
 
Join Date: Jul 2006
Location: Somewhere over the rainbow
Posts: 515
Sonicbum it’s just pilot techniques. As long as your company allows you and it’s not against the manufacturer recommandations where is the issue. Of course you could do the whole flight in managed and autoland. That’s the safest and easiest way.. But we are pilots aren’t we?
Saying that I don’t really think keeping A/Thr off is a good idea as you have no protection against overspeed. It’s easier to just wind up the speed target few knots below Vmax; At least the engines will spool down if you inadvertently fly too fast.





Last edited by pineteam; 29th Jul 2019 at 11:01. Reason: typo
pineteam is offline  
Old 29th Jul 2019, 13:54
  #26 (permalink)  
 
Join Date: Mar 2006
Location: USA
Posts: 1,349
Originally Posted by vilas View Post
Check airman, as you can see one person feels VS is better than Climb, you feel it will be even better with ATHR off. It doesn't end there. The tinkering will carry on. ​​​But manufacturer who designed the aircraft have more qualified people what do they feel is the most important. If you don't like what they want you to do tell them. As you mentioned about filtering of speed there was no way of knowing that for a line pilot unless the manufacturer told them. So line pilots should follow recommended procedures and not develop their own. Definitely not in Airbus. If you feel something doesn't work or you have better idea than Airbus discuss with them. Toulouse oversees everything from Argentina to Korea(longer way). When someone wants to do it differently in Korea may be someone already had an incident doing it in Argentina. So let them tell you. Every tinkering may not be as dangerous as QZ8501 but better be safe than sorry. There are climb speeds no climb vertical speeds. VS can definitely be used as a short term intervention for whatever but not as a standard practice.
I think you missed the points I was trying to make. Firstly, regarding the AT, it just feels weird to me, having the speed target set to Vmax, and my actual speed at some number below that. Instead of trying to trick the plane into doing what I want (ie. keep clb thrust), I'd rather just drop down one level of automation and fly with the AT off. It just seems neater to me, and that way it's easier to tell at a glance if I'm at my target speed. I've never used this techniques as PF though.

My second point about the filtering was just to point out that the common argument of "OP CLB isn't smooth" is not really true on an A320. I flew an airplane where the equivalent of OP CLB could really get twitchy in bumpy air, but the Airbus AP is a fair bit more sophisticated than that AP.

Personally, I stick to OP CLB and CLB. Easy, smooth, and safe. The odd time it levels off in a 321, I haven't had ATC complain (they're well aware of our climb performance when heavy), and temporarily reducing the mach is my preferred technique.
Check Airman is offline  
Old 29th Jul 2019, 14:02
  #27 (permalink)  
 
Join Date: Mar 2012
Location: Having a margarita on the beach
Age: 100
Posts: 1,293
Originally Posted by Check Airman View Post
temporarily reducing the mach is my preferred technique.
It is also the manufacturer's one.
sonicbum is online now  
Old 29th Jul 2019, 17:30
  #28 (permalink)  

Only half a speed-brake
 
Join Date: Apr 2003
Location: Commuting home
Age: 41
Posts: 2,479
Originally Posted by vilas View Post
Nowadays VS is generally used in RVSM towards last few thousand to prevent TCAS.
Just to make sure the biggest headbang item of the thread so far does not go unnoticed.

FlightDetent is offline  
Old 29th Jul 2019, 17:32
  #29 (permalink)  
 
Join Date: Jun 2007
Location: Wanderlust
Posts: 2,237
I think you missed the points I was trying to make
No! I didn't. I am against the whole concept of doing something not written in the book whether pineteam way or your suggested way. All it takes to climb is single push or pull on the button. No need to find a complicated way. The system is supposed to maintaine the speed by varying the pitch and it does so.
vilas is online now  
Old 29th Jul 2019, 18:46
  #30 (permalink)  
 
Join Date: Feb 2017
Location: Isla Grande
Posts: 714
Originally Posted by sonicbum View Post
I am sure Your airline is very happy with You using V/S rather than CLB.
Well, it depends.

The A340 IMHO is kind of a rollercoaster getting close to max, even opt alt.
Chasing speed by large pitch movements.
V/S of, let's say 500 ft/min, serves the problem.

And yes, my airline likes it
gearlever is online now  
Old 29th Jul 2019, 19:57
  #31 (permalink)  
 
Join Date: Mar 2006
Location: USA
Posts: 1,349
Originally Posted by vilas View Post
No! I didn't. I am against the whole concept of doing something not written in the book whether pineteam way or your suggested way. All it takes to climb is single push or pull on the button. No need to find a complicated way. The system is supposed to maintaine the speed by varying the pitch and it does so.
My suggested way is with OP CLB. What I'm saying is IF i opted to maintain a specific VS with climb thrust, I'd do it with the AT off. I wouldn't employ pineteam's technique, but it's not against SOP (at my company) and isn't inherently unsafe. I can't criticize him any more than I can criticize somebody for intercepting a localizer in NAV.
Check Airman is offline  
Old 29th Jul 2019, 20:03
  #32 (permalink)  
 
Join Date: Feb 2017
Location: Isla Grande
Posts: 714
Originally Posted by Check Airman View Post
My suggested way is with OP CLB. What I'm saying is IF i opted to maintain a specific VS with climb thrust, I'd do it with the AT off. I wouldn't employ pineteam's technique, but it's not against SOP (at my company) and isn't inherently unsafe. I can't criticize him any more than I can criticize somebody for intercepting a localizer in NAV.
Interesting.
In my outfit it's a no no to intercept the LOC in NAV.
gearlever is online now  
Old 29th Jul 2019, 22:51
  #33 (permalink)  
 
Join Date: Mar 2006
Location: USA
Posts: 1,349
Originally Posted by gearlever View Post
Interesting.
In my outfit it's a no no to intercept the LOC in NAV.
Ha! What's the reasoning behind that? How do you deal with the fuzzy signal far out? TRK mode?
Check Airman is offline  
Old 30th Jul 2019, 00:37
  #34 (permalink)  
Thread Starter
 
Join Date: Sep 2018
Location: Seattle
Posts: 7
Some great information and opinions on here, thanks.

FWIW in our lot, above FL300 we must use V/S in the climb...
BoeingDriver99 is offline  
Old 30th Jul 2019, 01:49
  #35 (permalink)  
 
Join Date: Mar 2006
Location: USA
Posts: 1,349
Deleted msg
Check Airman is offline  
Old 30th Jul 2019, 01:52
  #36 (permalink)  
 
Join Date: Mar 2006
Location: USA
Posts: 1,349
Originally Posted by BoeingDriver99 View Post
Some great information and opinions on here, thanks.

FWIW in our lot, above FL300 we must use V/S in the climb...
Indeed. What type does your lot fly?
Check Airman is offline  
Old 30th Jul 2019, 02:33
  #37 (permalink)  
 
Join Date: Jun 2007
Location: Wanderlust
Posts: 2,237
Ha! What's the reasoning behind that? How do you deal with the fuzzy signal far out? TRK mode?
I haven't flown 737 but I seem to have read they recommend it. In GPS primary age Nav is OK. Airbus has LOC Convergence and Enhance Loc Capture functions.
vilas is online now  
Old 30th Jul 2019, 02:56
  #38 (permalink)  
 
Join Date: Jun 2007
Location: Wanderlust
Posts: 2,237
Originally Posted by Check Airman View Post
My suggested way is with OP CLB. What I'm saying is IF i opted to maintain a specific VS with climb thrust, I'd do it with the AT off. I wouldn't employ pineteam's technique, but it's not against SOP (at my company) and isn't inherently unsafe. I can't criticize him any more than I can criticize somebody for intercepting a localizer in NAV.
How things go around. In old 747 classic for climb only IAS or vertical speed was available, and off course Auto throttle was not available so CLB thrust was manually set. When change over altitude was reached you had to maintain the Mach in VS mode. Later Mach mode and FFRATS(Full Flight Regime Auto Throttle System) was developed the practice of VS was stopped and you simply selected Mach mode for climb. Now in a sophisticated FBW A320 some prefer the archaic practice.

Last edited by vilas; 30th Jul 2019 at 03:14.
vilas is online now  
Old 30th Jul 2019, 03:22
  #39 (permalink)  
 
Join Date: Sep 2016
Location: USA
Posts: 430
All this aside, a small part of me died when someone described an autopilot mode as more "fun" than others
Vessbot is offline  
Old 30th Jul 2019, 05:16
  #40 (permalink)  
 
Join Date: Jul 2006
Location: Somewhere over the rainbow
Posts: 515
Hahaha! I know right! It’s unacceptable to have fun flying nowadays!
Flying the NEO today!! Woop woop!! Fun alert!! xD
Ok nuff off topic for me! CI 25 for us. They don’t monitor it or at least they don’t care if we play with it. I never change it except temporary to check CI 0 to know the VY speed. I’m flying the speed I’m getting paid for cause I’m a good professional
pineteam is offline  

Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.