Both hands on flight controls after V1 - tradition, myth or technical fact.
 

It is generally accepted wisdom that the PF should keep one hand on the thrust levers during the latter part of an automatic approach with auto-throttles engaged. Presumably this is because of the remote possibility of an auto-throttle malfunction.

That being so, why is the PF required to remove his hand off the thrust levers at V1 in order to rotate with both hands and therefore run the same risk as above of an auto-throttle malfunction. What is the perceived problem of conducting a one handed rotation and having the other hand guarding the thrust levers? Is the two-handed rotation a mere tradition in the airline industry, or is there a technical reason. And please don't say it is because it's easier to keep the wings level...

It's not to hold the column with both hands it's to prevent changing the thrust after V1.

One reason I can think of to remove your hands from the thrust levers after V1, is to avoid retarding them; i.e. rejecting the take off.
Another the rotation rate required on some aircraft needs some precise handling to avoid a tailstrike.

My guess is, as with most things in aviation, it all started before the days of automation. I would want to believe that before autothrottles came into being, the PF would have his hand on the control column after rotation, while the PNF and/or FE would have his hand of the power levers/thrust levers/throttles and monitering engine parameters. Thinking back to flight school, I remember being taught to keep a hand on the throttles during initial climb out to prevent them from being retarded due vibration.

Funny picture, grapping the sidestick with both hands....

After V1, your hands should be nowhere near the throttles, to help prevent any reflex action involving the throttles, until a safe height is reached. So if you are operating an aircraft with a yoke, then grab the other "horn."

There maybe an exception to this, in the event of a double engine failure on a 4engined heavy a/c just after V1.

I also stand to be corrected!

Aren't most autothrottles 'clamped' above a certain speed if engaged in T/O mode (actuators freeze, A/T reverts to armed for mode change after T/O)? A failure in the A/T logic would not lead to power changes in that case.

Hands are off the throttles above V1 to prevent PF from making inadvertent power changes, especially retarding them in case of engine failure above V1.

Moving one's hand from the thrust levers at V1 is symbolic in nature; it symbolizes that the point has been reached, previously decided before initiation of the takeoff run, at which the airplane is going flying should an emergency arise. Removing one's hand from the thrust levers is a form of commitment to the remaining takeoff; one is setting aside the decision to retard the thrust levers, and has committed to flying the airplane off the ground.

Keeping your hand on the thrust levers during an approach isn't merely for the sake of an autothrottle malfunction. In the event you need to continue the approach or make changes to the approach, you're the person manipulating those thrust levers. You're not so much guarding them in case the autothrottle suddenly retards them; you're there to take over, and at some point you will take over. In effect, you're doing the opposite of what occurs on the takeoff. On the takeoff, you have the thrust levers until the aircraft takes over (for those of you who use autothrottles for takeoff; I don't), or until the thrust is set for takeoff. On landing, if you are using autothrottles, the thrust is essentially set until you arrive at the runway (autoland excepted), at which point the airplane is given back to you.

On approach, the airplane has to do something; be it autothrottles of you, someone has to be manipulating that thrust lever all the time. On takeoff, conversely, the thrust is set at max or reduced, and you're not managing the approach angle at all, and your airspeed is manipulated by pitch. Set the thrust and go. Not until your initial thrust reduction during a standard noise abatement departure and then setting thrust later in the same procedure, do you again touch them. Not so for the approach and landing; the thrust levers are constantly being adjusted, or at a minimum gaurded to make an adjustment should it become necessary, either by you or the airplane.

In the company I work for, the captain keeps his hand on the thrust leavers until V1 because in the event of an RTO, it’s him that stops the aircraft. As far as I’m aware, the captain’s hand comes away from the leavers at V1 so that there is no reflex reaction to stop the aircraft after V1 should something go bang. It removes the temptation to try and stop, when the decision has already been made to go, that’s my understanding of it anyway. :)

AT systems used during take off must have a safety feature such that at fault will not change the thrust. Hence "HOLD" mode. Even if the AT system goes haywire it cannot change the thrust.

May be called something else on each type but is active from about 60kts to 400ft.

Let's change the topic to "What is the scariest stunt the FO has ever pulled on you?"

..told me he wanted my babies..

Take-off, auto throttle at set take-off power, not modulating.

Approach (B717), auto throttle modulates until flare (30') when they retard to idle.

Hence, guard them on approach but at V1, remove the temptation to suddenly retard them if there's a big bang. :\

All fairly well the same responses...

Boeings have a "Throttle Hold" function that unpowers the A/T actuators at a set point during the takeoff roll.

For the 737NG it is at 84 knots, and the FMA reflects that change.

After that, for the rest of the takeoff, the throttles are totally manual!

If you're a bit slow getting the thrust up to spec, at 84 knots the throttles will stop advancing, manual input is then needed.

Since most V1s are well in excess of 84 knots, removing one's hand from the throttles at V1 is not a problem!

But, if you abort before 84 knots, and 'as you do' retard the throttles to idle and beyond, the autothrottle will still be trying to advance to the selected takeoff power setting. But above 84 knots, will not!
This is why we select disconnect of autothrottles for every abort, then that's one thing you don't have to think about.

Normal ops for us!

Cheers...FD...:)

Judging from the replies to the question there is no compelling technical reason for the pilot to use both hands for rotation (see Airbus sidestick). That leaves tradition and myth. Taking your hand off the throttles just in case you succumb to a reflex action of jerking them back if you get a fright, suggests a myth. Like the reflex action of slightly lifting your bum off the seat when you know the other pilot is about to bash the Boeing on the bitumen. "Bit late on the flare, Bloggs...."

Different I believe if you are being shot off an aircraft carrier where the enormous power of acceleration can cause you to pull back the throttle(s) - hence hand is kept at the back of the throttles and not on them.

That leaves tradition. And tradition is just another name for someone's personal opinion years back.

Verdict: One handed rotation is perfectly safe - it's done every day on light twins and singles.

Errr, no? Remove your hand at the call of "V1" to prevent you from retarding the thrust levers when a warning goes off. No myth, seen mistakes made in the sim. No myth, factual error management procedure.

PP

Nonsense. Weasel words. Like the characters one occasionally observes in the simulator and the real thing, who grasp the throttles in claw-like embrace with knuckles well over the knobs ready to rip back the power before V1 and then the loud exhaled half-sigh of palpable relief when rotate occurs and the DANGER is over until the next take off...

Centaurus- so you are saying that it would be acceptable to leave your hands on the thrust levers past V1? Many an aircraft has gone off the end of the runway because of a post V1 abort.

Perfectly acceptable and good airmanship.

Don't worry, Centaurus is from Australia...:}

I use two hands because I'm a weakling, but mainly because it gives me better pitch-rate control during the rotation.

And if you don't have your hands on the throttles after V1, there is very vey little temptation to re-grab them after a big bang before liftoff, as previously mentioned.

Big Red Rat teaches hands off at V1 to prevent accidental thrust lever reduction. Not for mythical reasons. Red Rat shorthaul even teach keeping hands off thrust when getting airborne - no sure why that is (apparently due to 737s autothrottles and servo reliability?)

I think good airmanship is to keep hands away at V1 - hence the discussion of thrust hold etc. After all if you suddenly need you hand back on the thrust how long does it take? 1 second?

Good grief no - Not one airline I've ever heard of nor any aircraft maker recommends that. As mentioned above, there are excellent reasons to keep your hands well clear of the thrust levers post-V1.

Moi aussi - geddit.
Funny thing tradition. From the very first flight I had on a Tiger Moth to operating all types of military and civil aircraft from one to four engines, I was always taught to keep one hand on the throttle(s) for not only the entire take off run but for initial climb out. I guess throttle friction nuts were not as good those in Boeings. But never once was I tempted to snatch the power back in reflex action against a sudden noise. I guess the training of modern airline pilots must be lacking somewhere along the way if they are so twitchy as to jump with fright and pull back a throttle for no reason.:D

Are you Mad
 

A375 or whoever you are..........if you want to stop - you grab the shiny levers and rip'em back..........grab the reverser things and jump on the brakes.........all at once...right? (sort of)

Then if you want to fly i.e. at V1 and above you need both hands on the wheel (Non-sidestick stuff) so you can hand fly and cancel any yaw-roll couple that might come your way.

Unless of course you have major muscles and can tweak the wheel one-handed with such finesse....but I suspect your muscle development is mainly between the ears?

Like I said......you must be mad or senile or both.

But be happy anyway.

:ugh::=:*:E:*:ouch:

1. I agree with the majority that "hands off" at V1 is a good idea and stops any unwanted inappropriate reflex movement of the TLs. If you really need to do something with them after V1 (windshear, etc.), you know where they are.

2. Transferring the spare hand to the control column, if you have one, helps as you can perform a more accurate rotation. Physically, the accuracy to which you can apply a particular force is in inverse proportion to that force, so two hands are better than one in this respect.

3. It appears to be SOP in most airlines.

No Australian airline does.

seems like most of the participiants of this discussions are flying aircraft where you can afford to fly with just one hand - they can discuss what to do with the other.

Aviation has been invented in the times where you needed both hands to fly, and that is during take off and landing rotation. Obviously in modern Boeings that isn't the case anymore (I'm not flying them). But it seems that it is continued as a myth - so at least you still are doing the right thing.

Dani

Once again, I take the side of my colleague, Centaurus. IF a pilot, after passing V1, decides to reject (for whatever reason), I would submit that having one hand on the throttles or having both hands on the flight controls (notwithstanding the side-stick-controlled machines!) is not likely to be the governing issue over the resulting action.

On a more serious note, remind me to not fly with any American airlines if they keep their hands on the Thrust levers after V1.

This scenario is not as far-fetched as it may seem. V1, rotate, lift off, one hand on thrust levers. PNF is in the act of retracting the gear. Bird comes thru windscreen - make that a big bird, say pelican-sized - whacks PF senseless. As he slumps back in seat, he hauls the thrust levers back, probably with control column coming back as well, but at the very least with aircraft at about V2 plus 5, say 10-12 degrees nose up.
Try it in the the simulator (sans pelican).
PNF will not prevent the crash, and no pelicans will be harmed in the shooting of this scene.

If you don't need both hands on the stick, at V1 at least put your spare hand on your knee and leave it there until you need to actually do something with that hand.

Modern turbine aircraft do not need the throttles guarded to prevent them vibrating back. Guarding throttles is one of those quaint throwbacks to the DC3 era. Most of us no longer do 3 pointers either, so Centauris, while I often agree with your take on flying, let this one go to the majority.

AirRabbit,
I think the issue is more subtle. A decision to reject after V1 - fine; what taking your hand off the TLs does is guard against an unintended rejection, possibly brought about by your colleague saying "STOP!" instead of "Rotate" (has happened at least twice in my airline...) or indeed anything else that might trigger an unwanted response. IMHO we do not physically practice these sort of scenarios nearly enough to be absolutely sure what we might do under all circumstances; best not to leave it to chance, then?

If you really feel the need to do something with the TLs after V1, you still can but it will be a more deliberate action (you can still be pretty rapid if you want to).

Brakes
 

FullWings

When the Decision / Call is "Stop", the immediate action is brakes, then the thrust levers / reversers etc in quick order.


Tmb

Tmbstory,
During a high-speed RTO on many jets, the autobrake is triggered by retarding the thrust levers, the spoilers by the TLs or reverse selection. If the autobrake is available, it is generally recommended that you keep it in (by not stepping on the brakes) as it's much better at bringing the aircraft to a halt and you can then concentrate on keeping it going in a straight line.

The point I was trying to make was not about what order you did things but how to prevent an undesired RTO post-V1 by moving your hand away as V1 is called...

This policy by some operators of empowering the first officer to use the word "STOP" frightens the hell out of me. Will that cause the captain to blindly abort the take off (or rotation worse still) without knowing exactly what perceived event caused the PNF to make this loud squawk. Thread creep I know but surely the safest action under these circumstances is to call the nature of the problem eg engine failure or fire, master caution door open and so on and it is then the decision of the captain to take the required action

At V1 I drop my hand behind the throttles on the throttle quadrant and put my pointer and index fingers against the base of the throttle levers. That way I can feel any power changes.

FO, all 100-105 lbs of her, flies with one hand. How can someone so tiny fly with one hand while guys 2-3x her weight can't?

Tailstrike avoidance? Myth IMO. I doubt the afore mentioned FO can rotate as suddenly with one hand as a 200+lbs guy can with two hands.

At V1 I raise my hand momentarily from the thrust levers to the FA call button for coffee then ever so relaxed in an easy going languid fashion casually drop my hand back on to the thrust levers. :D

On T/Off on a dark moonless night with Auto thrust. I rotated the A310 with both hands on the control column and asked for gear up. As the gear retracted, No 2 engine T/Lever retarded to idle. ??? From that day on One hand on Column and One hand on T/Levers after rotation. :ooh:

In my airline FOs can call stop for a limited number of failures: any fire, engine failure (must be indicated by two parameters), Windshear Ahead warning or Monitor Radar Display warning. In addition, when PF, control difficulty or blocked runway.

Our FOs are well trained and competent. If they are not competent to call stop in the above circumstances then one would have to question their suitability to be pilots.

Our FOs are also allowed to start the engines, handle the the thrust levers, and taxy the aircraft too. They have slightly stricter landing limits than captains.

To waste time pointing out an engine failure or a control problem to a captain and then waiting for him to call stop would seem unnecessary and possibly disastrous.

For all my military flying career I was empowered to call stop from the FE seat.

I had to un-train myself when I started flying civvy. My first sim evaluation resulted in 2 Swedish pilots and 2 Swedish instructors looking at me in amazement when I called stop on the first take off of the session. I had to laugh when they told me only the captain can call stop. From then on I had to adopt the mentality that we were above V1 at all times and call the failure rather than the action.
Just adds micro seconds to the proceedings with no added safety as I never had a captain continue after a call.

I'm a believer in knowing what the throttle levers are doing.

http://www.airdisaster.com/cgi-bin/v...&airline=Tarom
Date of Accident:31 March 1995Airline:Tarom Aircraft:Airbus A310-324

At that time the auto throttles (on 'climb' mode) should have reduced power to the pre-determined climb setting on both engines. But the right power lever (no.2 engine) remained in takeoff power setting. It took the no.1 power lever 42 seconds to move to idle power. During these 42 seconds an asymmetric thrust situation developed.