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

Manual Thrust on A320's READ THIS! :)

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

Manual Thrust on A320's READ THIS! :)

Thread Tools
 
Search this Thread
 
Old 1st Apr 2004, 13:44
  #1 (permalink)  
Thread Starter
 
Join Date: Feb 1999
Location: UK
Posts: 58
Likes: 0
Received 0 Likes on 0 Posts
Exclamation Manual Thrust on A320's READ THIS! :)

I was just wondering whether operators of the Airbus A319/A320/A321 aircraft allow their pilots to fly the aircraft with manual thrust?

The reason I am asking is that I fly for a major UK based airline and we are currently allowed to fly with manual thrust if we desire for practicing manual flying during approaches.

However the plan is to ban the use of manual thrust and mandate autothrust. I have a number of concerns with this.

1) We will have "new" first officers coming into our airline having only flown Cessnas and Senecas and they will never have moved the thrust levels on the aircraft they fly, except in the simulator (which we all not is not 100% realistic) and when moving the levers from Idle to Flex and back to Climb and then from Climb to Idle.

2) There are MANY failures which lead to the loss of autothrust. So we will have flight crews that do not know anything about thrust lever position, power settings etc and then all of a sudden the autothrust fails and they are left wondering what to do with it?!

Also, any Airbus pilot will know that the autothrust is not the best in the world, it is often slow to repond and then adjusts too dramatically. This is not the smoothest way to fly manual approaches or visual approaches.

My view is that if the pilots are having problems flying with manual thrust, we should be training more use of manual thrust to get better at flying it! Its a pretty poor show if the pilot of a jet airliner cannot even set power settings manually whilst flying a fly-by-wire airliner that even takes care of all the trimming automatically for the pilot!

So therefore I am wondering if YOU fly an Airbus A320 series aircraft, does YOUR airline allow you to use manual thrust???????

Thanks.

David.
Dave is offline  
Old 1st Apr 2004, 13:59
  #2 (permalink)  
 
Join Date: Jul 2002
Location: here & there
Posts: 68
Likes: 0
Received 0 Likes on 0 Posts
Thumbs up

So therefore I am wondering if YOU fly an Airbus A320 series aircraft, does YOUR airline allow you to use manual thrust???????
Yes !!.........and recommends you practise regularly.


Roger Miller.
KingoftheRoad is offline  
Old 2nd Apr 2004, 06:48
  #3 (permalink)  

Sun worshipper
 
Join Date: Dec 2001
Location: Paris
Posts: 494
Likes: 0
Received 0 Likes on 0 Posts
Ditto,
if only to get used to the very small displacements of the'Bus throttles.
And like on any other aircraft,coordinated flying is not easy if you use A/T on manual flying (A zig in the zag...not a great way to have a stable pitch attitude).
Lemurian is offline  
Old 2nd Apr 2004, 07:35
  #4 (permalink)  
 
Join Date: Dec 2003
Location: Blighty
Posts: 91
Likes: 0
Received 0 Likes on 0 Posts
Does anyone know what BA’s policy is?
As far as I am aware the use of manual thrust on the 777 is against their SOP’s.
Does the same apply to the Airbus?

--
HaM
Half a Mexican is offline  
Old 2nd Apr 2004, 19:48
  #5 (permalink)  

PPRuNe Person
 
Join Date: Jun 2001
Location: see roster
Posts: 1,268
Likes: 0
Received 0 Likes on 0 Posts
HaM

Not yet!!

Who do you think Dave, the topic starter, works for??!!


Recently in an approach in a light 319 in moderate to severe turbulence, at night, we could not read the PFDs properly due to eyeball shake. The AP did a superb job but the ATHR did not, sadly.

We were forced to disconnect it to set a mean thrust as the ATHR had got itself totally out of synch with the gust patterns (about 70kts mean @ 2500' with 39kts on the ground).

ATHR was then re-engaged lower down the approach and as we reached the flare, a super-strength gust caused a sudden increase in IAS of about 15kts. A go-around was considered as the ATHR responded slowly.

These kinds of winds are rare, but any company planning to restrict the use of manual thrust will encounter an erosion of skill in its pilots.
overstress is offline  
Old 2nd Apr 2004, 20:06
  #6 (permalink)  
 
Join Date: May 2001
Posts: 85
Likes: 0
Received 0 Likes on 0 Posts
I don't fly the 'bus, but I am similary worried about the rumours that we will have to fly with the flight director on all the time, for similar reasons as the above. It also bothers me that some people think that disconnecting the autopilot in the London TMA is a bad idea.

While it is certainly true that there are a greater number of 'events' without use of the automatics, I think it is because manual flying is not practised nearly enough.

Those pilots I fly with who regularly practice with the FD/Autopilot/Autothrust off have a much better capacity and make less mistakes in all areas of the operation as they have a bigger 'capacity bucket'.

The above still has a tangible but less noticable effect in very experienced people, but from my own point of view MY flying got many times safer when I felt confident and became proficient at manual flying. It made me more aware of my mistakes and limitations and salvaged my non existant scan, which no matter how good your flight director is key to safe piloting.

I don't want to hijack the thread or creep it into a different argument, but I think the autothrust/FD argument are very similar.
ornithopter is offline  
Old 2nd Apr 2004, 22:02
  #7 (permalink)  
 
Join Date: May 1999
Location: U.K
Posts: 63
Likes: 0
Received 0 Likes on 0 Posts
Lemurian quotes: (A zig in the zag...not a great way to have a stable pitch attitude).


If I am correct, in theory there should be no pitch/power couple on the A320 when flying in normal law, with or without ATHR.

I fly the Bus regularly and am a great believer in the regular use of manual thrust. At the same time I also encourage pilots to evaluate each approach individually as in certain instances it is more prudent to use the automatic systems.

All pilots should be proficient in both manual flight and the operation of the aircraft with the automatics engaged.

Fly safely everyone and stay proficient!!!!!!!!!!!!!!!!!!!!
Firm Touchdown is offline  
Old 4th Apr 2004, 01:41
  #8 (permalink)  
 
Join Date: Jun 2001
Location: UK
Posts: 3,982
Likes: 0
Received 1 Like on 1 Post
As the A320 is "trajectory stable" in Normal or Alternate Law it is perfectly acceptable to fly a manual approach with the autothrust engaged unlike "conventional" aircraft where the effect of thrust change will affect pitch trim and may be destabilizing. (Direct Law there is a pitch/trim couple so autothrust use is not recommended)

It is a while since I have operated the A320 but I seem to recall that the FCOM recommends use of autothrust in conditions of wind shear - has this changed? In the event of an incident when flying manual thrust in such conditions there may be an issue of liability to consider!!

Having done circa 1,800 hours on the A320 with many approaches into Funchal (before they lengthened the runway) I almost always used the autothrust during the approach since it seemed to do an excellent job at coping with windshear there. However, I am bound to say that some pilots insisted on using manual thrust for reasons which I failed to understand!

In short, my advice and experience were that it is best to use the autothrust for a manually flown approach. It is, of course, necessary to practise manual thrust for the day when failures etc occur.

Last edited by fireflybob; 4th Apr 2004 at 22:57.
fireflybob is offline  
Old 4th Apr 2004, 05:49
  #9 (permalink)  
 
Join Date: Nov 2001
Location: Front Left, Right and Center.
Posts: 115
Likes: 0
Received 0 Likes on 0 Posts
Have not flown the A320, only A332, A343 and A345.

Under normal (and abnormal - when avail) conditions the A/THR does a good job. There are however certain Law re-configs where A/THR is not avail, I therefore consider it prudent for a professional pilot to keep his skills honed and manually fly the aircraft when conditions are right.
El Peligroso is offline  
Old 4th Apr 2004, 06:44
  #10 (permalink)  
 
Join Date: Feb 2004
Location: A hole in the ground.
Posts: 15
Likes: 0
Received 0 Likes on 0 Posts
Manual skills

The Athr is a tool like so many others, in my view it works quite well, even in windshear conditions, Sometimes we are forced to fly manual in less that perfect conditions. e.g. The visual part on a tail wind non precision approach in those case the athr lowers workload by allowing the pilot to pay less attention to the airspeed in his scan. The Athr with the gs mini function does a good job in windshear probably better than a human pilot would.

Since everything can fail I practice fully manual flight regularly. For me it is also important to practice manual flight with the athr on, so I won’t only be confronted with the sensation of flying manual with unmovable thrust levers when I need to use the system on a windblown non precision approach.
bankrupt is offline  
Old 4th Apr 2004, 15:25
  #11 (permalink)  
 
Join Date: Sep 1998
Location: Oxon, UK
Age: 70
Posts: 126
Likes: 0
Received 0 Likes on 0 Posts
It may be of interest here that Lufthansa advocate that their airbus pilots do 1/3 of apps fully automatic , 1/3 manually flown with FD/AT, and 1/3 raw data/ manual thrust.
DCDriver is offline  
Old 4th Apr 2004, 16:49
  #12 (permalink)  
 
Join Date: May 2003
Location: UK
Posts: 441
Likes: 0
Received 0 Likes on 0 Posts
Have flown the 320 series for 6 years and 4000 hours and always found the A/THR does a great job in all types of weather.

Airbus recomends using the A/THR in turbulence and the ground speed mini is excellent (takes a while to get your head round it if you've never come accross it before)

Some of the posts regarding A/THR on the A320 on this thread I can't see coming from genuine airbus pilots!
Boeing 7E7 is offline  
Old 4th Apr 2004, 21:04
  #13 (permalink)  
 
Join Date: May 1999
Location: U.K
Posts: 63
Likes: 0
Received 0 Likes on 0 Posts
Fireflybob,

A320 is only 'trajectory stable' in normal and alternate law(pitch only). In direct law and mechanical back up there is most definately a pitch/power couple.

Manual approaches are permitted both with or without ATHR. Airmanship should dictate the level of automation that is used!



Basic theory of operation in normal law:

Sidestick movement in the pitch axis commands a change in ‘g’. Zero displacement is the command for 1g (i.e. no change in flight path). Once the correct flight path is established, it will be maintained regardless of speed/thrust changes and hence there is no need to trim.

Sidestick movement in the roll axis commands a given roll rate. Zero sidestick displacement is the command for zero roll rate.

When handling in normal law, resist the temptation to overcontrol. Make small inputs to the sidestick and then release to neutral. Unless an adjustment to the flight path is required, sidestick inputs are not required

Last edited by Firm Touchdown; 14th Jul 2004 at 00:52.
Firm Touchdown is offline  
Old 4th Apr 2004, 22:54
  #14 (permalink)  
 
Join Date: Jun 2001
Location: UK
Posts: 3,982
Likes: 0
Received 1 Like on 1 Post
Firm Touchdown, thanks for the correction - a slip of the electronic pen after a nights celebration - have edited my posting!
fireflybob is offline  
Old 4th Apr 2004, 22:55
  #15 (permalink)  
 
Join Date: Apr 2003
Location: england
Posts: 81
Likes: 0
Received 0 Likes on 0 Posts
hi all,
just quick question, im a ground dispatcher and go inside many different flightdecks i no the Airbus family is something special as it is very automated. i know that when you use a/thr you just shift the levels into t/o, flex, clb then idle. but when you control the thr manually do these gates become erelavant, once you have disengage the a/thr on the autopilot would you then just move the thr leaver freely like a boeing 737 leavers to get the thr setting you disere or do you still have to move the leavers between these gates?
excuses my ignorance i just had to ask?
jimbols6 is offline  
Old 5th Apr 2004, 08:47
  #16 (permalink)  
 
Join Date: May 1999
Location: U.K
Posts: 63
Likes: 0
Received 0 Likes on 0 Posts
Fireflybob,

My pleasure.

I am first to admit that the Airbus control laws take some studying to understand. They are especially difficult to explain after a few beers.

Jimbols6,

Once the aututhrust is 'off', the thrust lever quadrant can be used just like any other.
Firm Touchdown is offline  
Old 5th Apr 2004, 09:21
  #17 (permalink)  
 
Join Date: Dec 2002
Location: Germany
Posts: 66
Likes: 0
Received 0 Likes on 0 Posts
Over the past 2 years, I've decided I would keep the AT/AP/FDs at all times. Result : my last sim check was a nightmare. B737-300, 55 tons, no AT, no AP, no FD, on an ILS with only light 20 knots crosswind. I've been lucky the DJ in my back allowed me a second try because the first one looked very, VERY poor. I felt like I was somebody else.

I've completely lost all my sensations and reflexes. Visual pattern very inefficient, if any. This is it. I'm going back to my old habits, i.e. switching everything off as often as possible. I cannot keep on degrading my capabilities in such a way.

I think an airline demanding automatic systems at all times is making the wrong bet on the longer run. I'm ok with clinging to autos in busy TMAs because 4 ears is better than 2. But please, chieft pilots, allow your pilots to keep training up. Or there will be a bill to pay sooner or later.
bijave is offline  
Old 5th Apr 2004, 18:39
  #18 (permalink)  
 
Join Date: Aug 2002
Location: Switzerland, Singapore
Posts: 1,309
Received 0 Likes on 0 Posts
Is this new procedure within BA coming from top level or from fleet bureau? Every management pilot will know for shure that exercising manual approaches is elevating pilots skills. This fact is especially true for the Airbus family with its high level of automation. I am shocked that head of operations does not have that knowledge...
Dani is offline  
Old 6th Apr 2004, 09:07
  #19 (permalink)  
 
Join Date: Apr 2003
Location: england
Posts: 81
Likes: 0
Received 0 Likes on 0 Posts
firmtouchdown: cheers
jimbols6 is offline  
Old 11th Apr 2004, 13:50
  #20 (permalink)  
 
Join Date: Feb 2004
Location: asia
Posts: 196
Likes: 0
Received 0 Likes on 0 Posts
My current airline suffers from the religious use of automation.
It trains it's national pilots from scratch and they plug in the AP at the minimum allowable altitude to late on approach. FD all the way.Managed thrust, you would think that this is the only type available.
Result: Can't fly manual thrust or raw data approaches.
Practice Practice.
A good trick with Airbus autothrust ,that is slow to respond in turbulent conditions on approach, is to move the thrust levers just out of the CRZ detent and back in as the speed reduces to below the Vapp speed to an amount that you find uncomfortable. This causes the engines to begin to spool up earlier than they would if you did nothing.
International Trader is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.