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Meikleour
3rd Jun 2010, 19:01
I currently fly A320 series aircraft with a company that recruits a large number of cadet pilots ( ie. newly qualified but first large type )
A trend that seems to be creeping in with these new pilots( I assume that this is being taught to them) is for them, when they are PF(pilot flying), is to put their left hand back onto the thrust levers shortly after getting airborne, to `guard the thrust levers`.
Considering that performance is covered on a FLEX take-off and the Thrust Levers are not driven as on a Boeing, surely this practice may lead to involuntary lever movement, either up or down if an unexpected event such as an engine surge or bird ingestion occurs.
Could I open this up for comment from other operators as to their views about this practice. I must add that this is not an SOP in our manuals but appears to have migrated from the supplying TRO.

divinehover
3rd Jun 2010, 19:26
If your hand must be on the Thrust Levers during the approach, why not after rotation? As the PF the TL's are yours and you should be fully entitled to place your hands there. VMCA is not an issue so there is no danger should TOGA be applied. I don't really understand what the problem is here.

If you don't trust your pilots don't put them in the right seat.

DH

Reverserbucket
3rd Jun 2010, 20:20
Could this not be an instinctive carry over from their basic training? The large FTO's I know teach to guard the throttle(s) until a 'safe' height on the climbout is reached.

CAT1 REVERSION
3rd Jun 2010, 20:34
Not sure about Airbus, but at my company on the Boeings it is a regular practice to 'guard' the thrust levers on first level off and all subsequent level off's.

Reasons I can think of and have encountered in the sim;

- Windshear
- TCAS RA's
- Thrust lever clutch failure

The thrust lever clutch failure is a favourite in the sim, basically feels like an engine failure at level off as only one thrust lever retards, hence always a good idea to 'guard' the thrust levers.

I wouldn't like to 'guard' the thrust levers in areas of turbulance though, have witnessed a skipper many moons ago on a dash8 do this and ended up firewalling the engines - wasn't very nice experience at all!!!!

Don't know how the Airbus works, but with a sidestick I would have thought it would be even easier to 'guard' thrust levers than on the Boeings, and I would suggest a pretty good thing to do - No???

AeroBoero
3rd Jun 2010, 20:56
On our company there is a recommendation to keep hands on the thrust levers as long as there is RA indication.

But it is also considered good practice to maintain hands on till passing MSA on climbing or when below 10.000 descending. But not every one do it here on our "club".

AB

Sciolistes
3rd Jun 2010, 21:27
Boeing here. Hands off until acceleration, then guarded. Then hands off at flaps up clean speed and AP CMD.

misd-agin
3rd Jun 2010, 21:58
Technique only, which can become SOP when you can write the 'correct' way to fly. :ok:

Boeing guy, I personally remove my hands from the throttles approaching V1 and rest my hand behind them with the tips my index and middle fingers against the bottom of the throttle levers. If they move, I feel it immediately.

Air Tourer
4th Jun 2010, 04:11
Guarding the thrust levers, against what? No use for rollbacks, flameouts,
bird injestions etc. Do these levers ever creep back, or forward on their own? That TOGA indent. Doesn't the "indent" hold?
Also wondering on the Airbus where the levers don't necessarly move with changed power settings, if this effects T.O. , but I suppose A.T, normal law, etc doesn't apply during T.O. ?

And if the captain is sometimes the only one able to abort, would he want a young F.O. blocking the levers?
None of mine moved on their own except when a certain part broke and a spring took it to full throttle. By the third time, I was an old hand at it. :)

FullWings
4th Jun 2010, 13:09
I take my hand off at V1 then let the AT look after them for most of the rest of the flight.

If I don't like what the AT is doing at any point, I have the option of manually overriding it as the thrust levers are still there between the flap handle and the speedbrake lever, not wandering around the cockpit or hiding themselves in the toilet...

I am somewhat bemused by those who hold the TLs and control yoke in a sort of Vulcan death-grip, even when the AP & AT are both engaged and have been for the last five minutes! What do they think they are achieving? (Apart from annoying the NHP who ends up doing all the MCP selections and radio calls whilst the HP does...?)

Meikleour
4th Jun 2010, 14:30
Divinehover

I think you are missing the point of my post. Firstly, forget about moving throttles which may or may not move on their own. Airbus Thrust Levers are essentially electrical limit switches. You say that the thrust levers are `yours` as PF - well most companies have minimum heights, typically 400`aal before emergency drills are commenced. My concern is that when quizzed as to why these guys are grabbing the levers a few seconds after I have just removed my own hand to prevent any unwanted involuntary actions - they usually say that it is so that they can apply TOGA if there is an engine failure. Well, if you get an overtemp. on the EGT, high vibs, over N1 or a surging engine (with or without a birdstrike) then the application of TOGA thrust could be very bad news indeed especially when close to the ground., There is no rush for the selection of TOGA with an engine failure but TOGA may make an engine surge much worse and remember that a surge usually also means a temporary loss of thrust!!

3 Point
4th Jun 2010, 16:31
Captains hand on thrust levers till v1 then both pilots leave them alone till thrust reduction at which point they become the the PF's property again - that's what I was taught and I think it's in the Airbus SOPs. Anyone got an FCOM handy I don't fly the Airbus any more :(

kick the tires
4th Jun 2010, 16:54
FCTM: The Captain must keep his hand on the thrust levers when the thrust levers are set to TOGA/FLX notch and until V1.

Thats all the Flight Crew Training Manual says.

Personally, I teach people that there is no need to 'guard' the thrust levers during the climb. I find it quite disconcerting to see a young hand flash across the flight deck as soon as the wheels are off the ground, only to do ..... nothing!

As someone has already said, performance is calculated at Flex power alone, in fact this gives more than required as the actual temperature is lower than the assumed one.

I am a great believer that a considered action is more likely if the thrust levers are not being held at the moment of crisis after all, it takes but a second or 2 to push them to TOGA if it hits the fan, as it were.

After the above quote the next entry in our OMB (regarding TL's) is

AT THRUST REDUCTION ALTITUDE (LVR CLB FLASHING ON FMA)
THRUST LEVERS...................................................... .......CL
ANNOUNCE FMA......................................................... “THRUST CLIMB”

Move the thrust levers promptly to the CL detent, when the flashing LVR CLB prompt appears on the FMA. A/THR is now active.

misd-agin
4th Jun 2010, 23:36
Watching an animation of the Turkish 737 crash at AMS. Throttles advanced part way, reduced to idle, and then 8 seconds later were advanced to max power.

IMO it's a reasonable to assume that the pilot that pushed the throttles forward removed their hand from the throttles.

Sometimes training and SOP is designed so that muscle memory takes over during high stress events.

I believe the tactile feedback from moving throttles is important. The requires two steps - 1. moving throttles and 2. having your hand on the throttle levers.

Dream Land
6th Jun 2010, 13:30
Thread creep...and then there's the rudder pedal thing, cadets don't appear to understand that the rudder pedals are not foot rests, but are there to control the airplane. :ugh:

rudderrudderrat
6th Jun 2010, 15:29
Hi misd-agin,

I believe the tactile feedback from moving throttles is important. The requires two steps - 1. moving throttles and 2. having your hand on the throttle levers.

I agree with the above when Auto Thrust is engaged.

During Take Off & GA Auto Thrust is not engaged.
During a GA, either auto thrust should be designed to disengage automatically or pilot's trained to disengage it.

0-8
6th Jun 2010, 17:03
I believe the tactile feedback from moving throttles is important. There are advantages and disadvantages to both moving and non-moving thrust levers.

The Turkish 737 event is an interesting choice to support your case though. In this instance if the thrust levers had been the 'non-moving' type then they would have stayed where the PF left them i.e. in the TO/GA detent!

Denti
6th Jun 2010, 17:18
During Take Off & GA Auto Thrust is not engaged.

During a GA, either auto thrust should be designed to disengage automatically or pilot's trained to disengage it.

Depends on type i would think. On the boeing (737) you have auto thrust engaged for take off and GA (the latter depending on SOP). Of course during take off roll the mode will change to THR HLD and later on to ARM until climb thrust which engages automatically at a preset height.

Dunno about the bus though, they might do it differently.

shortfuel
6th Jun 2010, 17:28
You won't find a long literature about this...but I believe, cadet or not, airbus or not that having your hand on TL when gear is up is good airmanship.
Below 5000' AGL, I don't see any reason why your hand should be on your arm rest...

About your fear that this might lead to a wrong/involuntary TL movement after an event...I'd like to say that this has more to do with proper training than just having your hand on the TL.

What do your SOP exactly say? Is there anything clear about it?


Out of curiosity: where is your right hand when you taxi?

Wizzaird
6th Jun 2010, 18:21
Have to agree with 3 Point to have hands off at V1 until thrust reduction. As mentioned many times, the Airbus TL are just switches and are not going to roll back by themselves. Having hands off is a nice reminder not to make a knee jerk inappropriate action at a critical point of flight. If you need TOGA then fill your boots but I do not want my 200hr RHS deciding to mess with the TL's at 50 ft. During approach is different because we are operating at a low power regime close to Vapp and very occasionally it requires a nudge of power (out of the AT range but below TOGA) if the speed trend is becoming uncomfortably low! During taxi I keep hands on the TLs so I can smoothly anticipate power applications to counter gradients!

Meikleour
7th Jun 2010, 09:12
Wizzaird,

Thank you! We are singing from the same hymnbook! The real point is that you cannot teach EXPERIENCE therefore in the early days of a career there will always be situations that are encountered for the first time - its good practice to safeguard oneself.

BRAKEOUT
8th Jun 2010, 19:39
I agree totally. For incapacitation reasons - hands off thrust levers after V1 until thrust reduction after acceleration. Likewise on a go around - set the thrust and hands off. After all a go-around is only takeoff albeit at 200 ft or whatever. I see guys obey the first case but not the second, I wonder why?

Pro Spin
8th Jun 2010, 21:44
Hi

Does anyone have any examples of when one of their First Officers as PF has put their hand back on the TLs after rotation and made an action slip?

I suppose the only dangerous action slip would be to retard the TLs - has this actually happened to any fellow Airbus captains (in the sim or on the line)? Are there any case studies where this has been a contributory factor in any accident/incident?

Cheers

Pro Spin

Tankengine
9th Jun 2010, 03:00
I put my hand back on the thrust levers after takeoff.
This is so I can apply TOGA immediately I need it in event of an engine problem.
In the middle of an emergency is not the time to "be looking" for the thrust levers.
I am a Captain, 22 years experience on jets.
SOPS are hands on sidestick and thrust levers until flaps up, EXCEPT for V1 until after airborne.

muduckace
9th Jun 2010, 04:04
Forgive me but guarding the throttles seems to be a (no brainier) unless you are operating an aircraft that requires an unusual amount of force on the pitch or roll axis (do not know any to this spec.)

I did watch a captain argue with the landing f/o from G/S cap down to about 400ft agl to the point that that said capt slapped the FO's hand on the guarded throttle over this procedure.

Type was MD-11 and given the aircraft's landing charistic I felt the the F/O was more competent than the capt. by doing so.

I would also feel that unless the landing pilot flying any aircraft that could not be handled with a single hand (really how long does it take to to move the throttle hand to the yolk in a failed approach "TOGA" being the first response) that could not be done so responsibly is ridiculous.

I do not see how even by my uneducated (formally) view is not logical.

Meikleour
9th Jun 2010, 09:15
Tankengine

One of the main considerations of this thread was to point out the situations where the automatic application of TOGA would be a bad idea. Sure, it is there to be used if required but I would question the necessity of its immediate use. Performance should be covered adequately at the planning. stage.
In 43 years flying, including 7 years as an aircraft qualified Base Training Captain (cf. sim.qualified) I have experienced an engine failure at VR where the F/O shouted "#4 engine failure!" and then proceeded to grab the #2 start lever! Swift intervention followed. Also doing night A330 base training with the last item to complete being a Go-around from below 100ft. Despite the briefing and rebrief on finals, at the call the trainee closed both thrust levers rather than advanced them. Unfortunately for me he did remember to pitch up!

So, to all the advocates out there of the `throttle death grip` please ask yourself "what are the benefits to me versus the pitfalls?"
PS to all non Airbus contributors remember the thrust levers on the Airbus never move of their own accord.

Tankengine
10th Jun 2010, 06:24
Meikleour,
Your two examples do nothing to help your argument, the first guy grabbed the WRONG switch while the second pulled instead of pushed.:ugh:
I do not advocate a "deathgrip" on the thrust levers, merely that if your hand is on them you can push up to TOGA with little effort.:ok:
Better that than flailing around looking for them.:eek:
From my experience in the A330 sim pushing TOGA after takeoff has never been a problem, unlike NOT pushing it, which has!:hmm:
As I stated earlier, that is our company SOPs, so that is what we do.:)

Meikleour
10th Jun 2010, 09:23
Tankengine,
If your SOPs call for it, then that is what you do.
One of my points was that inexperienced crew may do unexpected things!
You still studiously ignore the situations that require not the prompt application of TOGA but rather the reverse! By the way, what do you do with the thrust levers when you do a TOGA take-off? Do you still guard them?

I used to work for one of the first A330 operators.( ie. 1995 onwards) After a few years we changed the Octopus speeds to Min V1s (company policy) This caused no end of problems in the sim. initially when guys added TOGA before they had fully got the pitch attitude under stable control. So, your experience may be relevant to your operation but not universal.

PS you don`t work for an outfit that once parked a B744 on a golf course off the end of 21L at BKK do you? I seem to remember that that incident involved some unexpected throttle movements between the two pilots involved.

Tankengine
10th Jun 2010, 13:30
Yep,
That operator, just shows what can happen when you let a checkie/management out of the office!:eek:
If the PF had not been overidden a normal go around would have occurred!
Still a reasonably good record Nigel.;)
Sorry, don't know what the octopuss is?:confused:

Meikleour
10th Jun 2010, 16:04
Octopus was the Take-off Performance Data programme supplied by Airbus. It was up to the individual airline Ops Depts. to specify the parameters to be used. In our case the company switched from normal mid range V speeds to minimum ones and this was what made the V1 cuts so much more critical. Less than 11PA no unstick - more than 13PA and speed would trend below V2 whilst the gear was travelling! Because of this more guys would tend to go for TOGA very early on and we saw quite a few very unstable rotations and near pod/wingtip strikes. Don`t misunderstand me. I am not saying don`t use TOGA just that not all situations require it.

As an aside, I believe the chap had visited my company to give us the benefit of his own CRM skills not long before the incident. Lets call it an incident - would not want to call it an accident!
I`m off now for a `tinny` or two!