737-200 V1 cut

[250hrsand counting]

on a 737 -200 any other cues on the v1 cut or engine out take off other than centering the ball with rudder, maintaining v2 and straight and level flight on the ADI

[Mach E Avelli]

Dead foot dead engine works fine as ONE means of identification, but is not of itself sufficient (see later comment about shutting down an engine). You could be experiencing some control asymmetry. Unlike some light twin training that you may have received, don't be tempted to give it a boot-full of rudder to keep straight, because if you do, it will roll badly and you will be in serious trouble. If you are doing the exercise in a simulator, it will probably crash to teach you not to do this. Just 'squeeze' the rudder enough (some describe it as 'step on the ball') to keep the ball within half a diameter of centred.
Obviously first job is fly it, second job is clean it up and third set max continuous thrust (many trainees miss this step in their haste to get on with the shut down drill). Whether or not you can engage autopilot for continued climb will depend on SOP and the actual autopilot fit, though obviously it is a better and safer operation with the autopilot offloading you during the next stage which is the identification and shut down. Some old B737 Jurassics don't take kindly to OEI autopilot operation, though if properly trimmed they should be OK. Ditto the simulator.
Then - and again unlike your light twin training, there is absolutely no rush to do this - go through the identification process at a safe height. In real life, jet engines rarely just go completely dead at exactly V1, even though we train a lot of this exercise to satisfy the licencing people. Same with engine fire - it is extremely rare to have fire with simultaneous total loss of thrust. So, in the real world (as opposed to simulator) chances are some thrust will still be produced and this would help you gain altitude and acceleration through clean-up. By 'sitting on your hands' for a minute or so you are using the dying engine to your advantage. But even if the exercise is a 'dead cut', no matter, no rush.
Before doing anything drastic like shutting down an engine, you should be identifying and confirming with your other crew which engine has failed, and indeed whether it has completely or only partly failed. EPR, N1, EGT and vibration indicators provide the clues. Don't be suckered into believing it is only a loss of oil because the oil pressure light is on or the gauge is reading low - that is usually a consequence of the engine running down. If it IS only loss of oil pressure, the engine will probably produce thrust for quite some time - more than enough to gently throttle it back and reach for the QRH.
Some SOPs actually require that an engine will only be shut down with TWO, or more, indications of failure. In the case of a fire warning with no loss of thrust or obvious over-temperature or vibration, that means the bell and the red light are counted as the two indications.

[Junkflyer]

Keep it on the runway a bit past v-1 to help you get the rudder pressure dialed in before lifting off.

[mustafagander]

Junkflier I think you might mean 'Vr". Either way that is extremely poor advice. Regardless of how you feel, rotate at Vr because that is the way your performance is calculated and on a limiting runway it will end badly if you use your own little ideas instead of certified data.

250etc don't try to be too academic here! Just look out the window and stop the world going across it sideways. Be very aware and ready to work the ailerons and rudder a little as you lift off, once again look out the window. A glance at the sky pointer is useful too. As Mach E says, use up the engine and don't be in too big a rush to shut it down. After all, if it has seized up or something a delay won't hurt it any more but if it is dying the thrust still available is pure gold for your performance.

Don't rush things, there is very rarely any need to be hasty and an error will be costly. A bit of armchair flying where you literally say out loud all the calls/statements required by your SOPs is a great help I find. If I'm swept up in the moment in the sim I know what I should say and do because I've been there in a virtual sense a few times.

[Hobo]

on a 737 -200 any other cues on the v1 cut or engine out take off other than centering the ball with rudder, maintaining v2 and straight and level flight on the ADI

I assume you are talking simulator here, so I'd just do what you say and it will climb away nicely with max cont set - as Mach E Avelli says. If the failure is while you are still on the ground then keeping it straight will give you the right amount of rudder to take into the air. Once airbourne, assuming you use EPR's then a good ball park figure is 1.6 needs 6 divisions of rudder trim, 1.3 needs 3 divisions etc.

If you get confused and crossed controlled (ailerons/rudder) ask PNF to set the right rudder trim on the EPR as above and sort the ailerons out based on that.

[nitpicker330]

Well actually no he's not totally incorrect.

Luckily in a lot of cases there is a split between V1 and VR which allows you to fix the correct amount of rudder before liftoff. This does help quite a bit. I wouldn't delay VR though if the split is small.

Once you put the Rudder in then lock your leg and only make small adjustments.

When you have the correct amount of Rudder the Control Wheel ( yoke ) should be level. If the Yoke is to the right then more right rudder ( or less left rudder depending!! ) is required.

Try not to over control!! :ok:

[Killaroo]

Machiavelli, if he's talking about Sim tips I have one. Forget 'the ball'.
Your average 732 Sim was probably constructed in the 70's, when Simulation technology was pretty basic compared to today's machines. The ones I've 'flown' most often had sticky balls (ahem) if they even moved at all. They were one of the least realistically simulated elements of the cockpit instrumentation.

The right way to handle a V1 cut in one of these Junkers is to concentrate on the sky pointer. Remember we are talking a SIM here, so I'm not saying ignore the ball in the real thing - but in a Sim, this works.
When the engine fails in the Sim you may or may not cop which one it is through other cues, but if all else fails you, just look at the sky pointer. As yaw creates roll you'll see the divergence clearly. The purists will hate this, but FOR THE SIM IT WORKS. You need to act reasonably snappy, because if you let the roll build up you'll lose it.

Another tip.
When you apply the rudder, put in the amount you think is correct (practice makes perfect!) then HOLD IT. Do NOT be tempted to cycle it - these old sims get confused by that and start displaying all sorts of unwanted behavior.
Get it climbing away, get the gear up, settle down, and now look at the control yoke. If its dead level and you're tracking straight - congratulations, you nailed it. If you need roll to track straight you'll see the yoke is displaced, and the 'down side' is pointing to the leg that needs more rudder. Make that adjustment gently. Trim it, and see how she's doing. Remember speed changes will quickly change the rudder required, so try to fly speed accurately.

Regarding holding it on the runway or not - ask your instructor to let you use a Wet V1 on the first few attempts. If he fails the engine at V1 you'll still have around 8 or 10 knots to gain before Vr. This gives you time to nail the rudder. Get the feel of it. Then try a standard V1 cut and use muscle memory for the input.
Those old sims don't yaw, so it is really challenging to catch a V1 cut with no visual cues. Remember that.
You're a hero when you are consistently doing it right.
The 732 is a real mans aeroplane. A joy to fly. The best days of my flying were on that wee beast. Sadly I now fly a computer with wings.

[Lord Spandex Masher]

Junkflier I think you might mean 'Vr". Either way that is extremely poor advice. Regardless of how you feel, rotate at Vr because that is the way your performance is calculated and on a limiting runway it will end badly if you use your own little ideas instead of certified data.



Actually no different, in practice, than using the increased Vr technique. As long as you're airborne before you run out of Tarmac there's no problem. It is a valid technique for engine failures and if practiced correctly results in a controlled take off as opposed to a wobbly one as witnessed by moi in the sim with the same student and same failure.

[JammedStab]

Personally, I did put a "bootfull of rudder" in when there was a V1 cut. What else can you do to maintain or stay close to the centreline.

The best advice here so far is the guys saying to hold that rudder input. I found for the sim that I was flying that the visuals were poor. After putting in the appropriate amount of rudder, the visual showed what appeared to be the aircraft rolling down the runway at a considerable angle to the runway. The first couple of times. I backed off the rudder and went off the side. The good advice you see here for locking your leg worked fine with strange visuals ignored.

I have to admit that I used the skypointer very little for the ground portion of the V1 cut as most concentration was spent staying on the runway. I suspect that the earlier poster meant for the airborne part.

Rotation speed is critical. Believe it or not, for normal ops the 737-200 was initially allowed a 6° rotation rate which is now 3°. Anyways, a nice controlled rotation rate to perhaps 12° nose-up should work and keep you from experiencing stickshaker.

During the rotation is when I would transition to instrument flying with a back and forth inside and out in order to monitor the pitch as well as still maintaining the centreline. Just going straight to the ADI risks allowing the aircraft to drift toward the runway edge.

Done properly, the aircraft seemed to find itself magically at V2 and now a good instrument scan is essential with good pitch control to monitor airspeed and frequent monitoring of heading which can be adjusted with minor rudder adjustments. Wings level worked for me and is the recommendation even if VMCA is affected by not banking into the live engine.

Aileron input was little to none as it risks spoiler deployment and increased drag on an aircraft that is not exactly overpowered. Perhaps someone can post at what control wheel deflection there is spoiler deployment. It is not a lot'

The next thing for me was four twists of the rudder trim knob to relieve rudder pressure required and try to hold everything to the acceleration height with a few minor inputs and continuous scanning.

Then accelerate and clean up with appropriate elevator trim as required while accelerating and backing off rudder input and retrimming as speed increases. I seem to remember a bit of a nose down tendency when the slats retract so that can be anticipated for the final flap selection. I never looked at the rudder trim knob itself during such a maneuver to check the amount of units. It was all done by feel as your instrument scan is critical.

I have to admit, I didn't look at the ball much either and seem to remember it being inaccurate in our sim. However, some of the more experienced posters may recommend more emphasis on the ball.

But its been a while so any comments are welcome.

[Killaroo]

Why are you in a 732 Sim anyhow? I thought they'd all been scrapped by now.:{

[Centaurus]

Its a few years since I "flew" a 737-200 simulator which was the Lan Chile machine in Santiago, Chile. The visuals were poor and I had doubts about its fidelity. I know for the 737-300 simulator you need to keep in mind that the take off stabiliser trim setting is based upon a two engine VR. Obviously same with the 737-200.

If an engine fails while you are still between V1 and VR, be prepared for a heavy pull at VR much more than you would normally expect. That is because with one engine failed on the runway, the vertical vector of thrust normal with both engines going, is halved. That translates into a nose heavy pull off the ground. Best thing is to ask the simulator instructor to hop in a seat and demonstrate the manoeuvre - if he is game to. Most won't because they are not confident to demo an engine failure on take off without making a fool of themselves:ok:

In the simulator with engine failure at V1, we frequently see people relaxing on the heavy back pressure during rotation and flying back into the runway a couple of skips before getting airborne. So be prepared for real muscling to get the aircraft up near to 10-13 degrees. When well clear of the ground by about 200 feet then a fair amount of back stab trim (about three seconds) is needed to unload the back pressure.

[5LY]

As Killaroo said, the most important thing you can do to stabilize your a/c is keep your controls straight in your hands. Step on the down side. If your controls are level, you have the right rudder input. If you're using a bunch of aileron to stay straight, then you're creating a lot of drag which may well be enough to prevent a positive climb.


A couple of posters have mentioned CON thrust. Unless there's been a dramatic change since I flew the old noise maker, you keep t/o thrust until the end of your second segment and until you are cleaned up. Only then do you select CON thrust.


Imagine that your live engine thrust lever is attached to the foot on the same side. When you make thrust adjustments as you fly to your landing runway you will be out of trim again every time you move the thrust. As an example let's say you are beginning to configure from clean. Assume your left engine is shutdown. As you put flap out you have to increase thrust on your right engine. As you make that thrust increase, your right foot pushes in at the same time. If you reduce thrust your foot comes back or reduces pressure a bit. During the flare you may have to step slightly on the dead engine side because you're trimmed for the approach and you don't have time to re-trim in the flare. At all times make sure that you do this enough to keep the stick (roll control) straight in you hands, unless you are turning of course.

[underfire]

Does the 200 have a gravel kit! :}

[Mach E Avelli]

Being pedantic, but Max Continuous Thrust is set at the commencement of the fourth segment, i.e. following final flap and slat retraction during the third.

Because the simulator is unlikely to have 'zero flight time' approval, it is probable that you will have to complete a base exercise in the real deal before qualifying for the type rating. If so, be very careful about any OEI stuff close to V speeds for light weights, given that the bird will likely be very light for training. Prudent flight instructors will use 'canned' V speeds that are higher than actual minimums and will use max derated thrust at all times. Also, hopefully, they will feed in any simulated engine failure by slowly reducing thrust. I repeat, if that happens do not use a boot-full of rudder and never, ever kick it. It is extremely powerful; enough to rip the tail off an old airframe. Rudder responds quite adequately to a gradual but firm increase in pressure - 'squeeze' it while simultaneously holding wings level and setting the pitch attitude for V2 to V2 plus 10. At training weights it is more likely to already be at V2 plus 10 or even plus 20 by the time the failure is recognised. If it is performing OK at that speed (it will be), stay with it - don't go hauling the nose up to come back to V2.

The Jurassic is a great thing to fly; the nicest of the 737 series, and with the lack of automatics you really feel involved with it.


Last question - some -200s were gravel kitted. Later Classics were not.

[john_tullamarine]

As long as you're airborne before you run out of Tarmac there's no problem

I think, no.

The observation is fine for the runway consideration .. but might just get the aeroplane into all sorts of obstacle clearance problems. Fly it like the ops engineering folk planned it or, else, get them to change the plan to fit the way you want to fly it.

[250hrsand counting]

@ Mach E Avelli Your post has been very helpful especially the first reply which states what I have been doing. I have no problem controlling the aircraft on the runway as the instructor gives me the cut 5-10kts before v1. I identify the left engine total failure and use the right rudder to control it, I overstep on the rudder(Multi Engine Training) and just before 400ft I am uncontrollably flying to the ground. Nose down, level wings fail to help me here as I get too close to the ground and I find myself fighting a big beast who isn't going to give in. Do you think a reduction of thrust while I stabilize the aircraft will help me in this critical phase of t/o while I try to gain full a/c control?(wings level as I approach the horizon).

[250hrsand counting]

@killaroo The main problem starts just after liftoff the plane(sim) tends to roll to the left assuming the left engine was cut on v1. I apply rudder maintaining v2 and it gets steady for a few 100 feet and then goes almost 45 degrees left on me. I start fighting the beast and it fights me even harder.
N.B the cut on approach is even better as I tend to control the plane in the air with rud trim but for some reason on t.o it just wins the battle which I am going crazy trying to win before my check ride

[250hrsand counting]

@5LY, mustafagander....NOTED.
@Centarus.... The instructor doesn't advise to use stab trim or rud trim till after thrust reduction height

[glendalegoon]

junkflyer has it. he has flown a 737-200 sim (or simmed it).

put some rudder trim in before you bring the nose up, it will make it easier.

this is for the SIM only mind you.

also, have the sim instructor turn up the engine volume...you can hear the engines go out of sync.

they taught us to look at our thumbs. ;-)

[Centaurus]

@Centarus.... The instructor doesn't advise to use stab trim or rud trim till after thrust reduction height

Every simulator instructor whether a current check pilot or not has his own personal views. These often contradict what is published in Boeing authorised manuals. From what you describe it is your instructor's purely personal whim that you should not use stab trim or rudder trim until thrust reduction. I have never heard of that trick before.

With any flight you use the stab trim to relieve stick forces just like ab initio flight in singles. IMHO your instructor is simply wrong in his assertion. Obviously you would not use stab trim during rotation but once comfortably clear of the runway it would be appropriate to keep the aircraft in trim. The last thing you need is fighting the trim changes until thrust reduction altitude.

[Mach E Avelli]

OK, it seems that you are dealing with an old simulator and have yet to develop a technique.
Firstly, if the cut is 5 to 10 knots BEFORE V 1 you should be rejecting the take-off. Do you mean before V 2 ?
So, assuming the failure is at or after V 1 it should be controllable if you hold it straight with a smooth but steady rudder input and commence a smooth rotation at V r, holding wings level with slight aileron input. It is essential to make small, steady corrections with each control (and this also applies to use of trim, thrust and speedbrake) to give the old computers and hydraulics in the simulator time to process what you want and provide the necessary feedback via control loading, instrument readouts and motion. A lot for the old thing to digest and if you start overcontrolling, it will quickly get out of shape, i.e. be seen and felt by you to be reacting poorly. It is certainly worse than the real aircraft, though not totally unrealistic. Old simulators simply do not process rapid or multiple inputs as seamlessly as the latest electric platform jobs, so the trick is make an input, wait for a result, then increase or reduce the initial input as necessary. Get the instructor to demonstrate his technique. If he won't, it says something about the fidelity of the sim, or the ability of the instructor.
Don't give up, just work on your simulator 'technique'. The aircraft will seem a walk in the park afterwards!

[rogerg]

I use an old 400 sim and Mach E Avelli (http://www.pprune.org/members/211776-mach-e-avelli) has it just about correct. As he says you need to use the rudder but be smooth gentle with all controls. Sometimes the rudder runs out of authority so dial in a little rudder trim to help.

[5LY]

If the a/c is rolling on you, you have either too much or not enough rudder in. Most likely it's not enough. I can't emphasize enough that if the stick is not straight in you hands your rudder is not applied correctly. Someone said look at your thumbs, they should be more less level with each other. Step on the downside to bring them level then trim off the pressure with rudder trim when you have time. Don't be in a hurry to reach for trim. It can be a distraction. Do it when you are fully stable.

[PEI_3721]

Few if any simulators have representative side force / lateral acceleration. The ‘ball’ might provide an indication, but the all-important body sense of going sideways is missing. Thus in a simulator the pilot lacks both a detecting sense for an engine failure, and a guide to the effectiveness of corrective action – how fast / much rudder application is required.
In part, this deficiency results in poorly matched lateral directional responses in the simulator. Also in some aircraft these aspects change with pitch rate/attitude and/or ground effect.

[AirRabbit]

Few if any simulators have representative side force / lateral acceleration. The ‘ball’ might provide an indication, but the all-important body sense of going sideways is missing. Thus in a simulator the pilot lacks both a detecting sense for an engine failure, and a guide to the effectiveness of corrective action – how fast / much rudder application is required.
In part, this deficiency results in poorly matched lateral directional responses in the simulator. Also in some aircraft these aspects change with pitch rate/attitude and/or ground effect.

Once again PEI I have to admire the way you think. Not many of today’s aviators are particularly knowledgeable about the simulation they use day-in and day-out with respect to the fidelity to which they are exposed when IN their particular simulator – and I think that is one of the points you were making – and which I believe is accurate. However, I do have to offer corrections and explanations to your opening statement.

While it is true that there are quite a few simulators in use today, as anyone would recognize, the 6DOF simulators that have entered service, particularly those entering service within the past 10 – 12 years or so, are quite good – and do provide the kinds of side-force/lateral acceleration (as well as acceleration forces in all of the degrees of freedom characteristic of an airborne airplane) that you say is not very common. The correction I think is necessary comes from the fact that, in the US (and unfortunately I don’t have access to similar numbers for the rest of the world) of all the aircraft flight simulators (not flight training devices) in service today number just a bit more than 660 – where only something like 25 of them do not incorporate a 6DOF platform motion system. Surely, the more modern the simulator, the more technically capable it will be – and those placed into service within the past 10 – 12 years would be expected to be at the top of that list of most technically capable – but 635 out of 660 is certainly not “a few.”

Of course, anyone familiar with simulation will recognize that using a simulator that is mounted on the kinds of motion system bases currently in use cannot provide sustained “g-forces” (i.e., accelerations) in any of the degrees of freedom – but, even in the airplane, it is the “on-set” cues that provide the most significant cueing to the pilot at the controls. Once that “on-set cue” is recognized, there are other, equally important references that any pilot can (and should) use to verify the initial acceleration … outside visual references, instrument responses, sound cues, to name just a few. I can say this because in an airplane were a pilot to experience a recognizable and continuous “g-force” (acceleration) in any axis, that he/she did not initiate and is not maintaining, that pilot should immediately recognize that an abnormal condition exists and should be taking immediate steps to correct the flight path. Some will argue that as long as “acceleration” continues, the associated “g-forces” will continue to be experienced, and from that, conclude that my statements here are “bogus.” To those persons I would recommend the following … if you have the availability of having an additional person in the cockpit or if you can suspend something from a non-objectionable location in the cockpit, which is observable by at least one of the pilots, where this object, having at least some relative weight, can be suspended by a string or thread or similar, and allowed to swing freely during taxi-out … during the takeoff roll, you will see this object be displaced toward the rear of the airplane (displacement opposite the direction of aircraft movement and in the direction of acting force on stationary objects in the airplane) and as the acceleration continues, you will see this object begin to return to its original “straight-down” position. Depending on the smoothness of the runway surface and the timing to the initiation of the rotation for takeoff, the suspended object will return to its original, straight down position relative to other objects in the cockpit – because it too, will be accelerating at a rate that will eventually equal that of the airplane – and while the airplane continues to accelerate toward rotation speed, the suspended object will (until rotation is initiated – when acceleration forces are changed) retain that straight down position. You’ve recognized this exact sensation on every takeoff you’ve ever made. Initially, you are pressed into the back of your seat, but eventually (sooner, rather than later) you, just like the suspended object, just like the airplane and all of its contents, will continue to accelerate to match the acceleration of the airplane – and since there is no acceleration differential along that axis, all seems to return to just what it was just prior to brake release.

As a pilot you can confirm your continued acceleration by outside visual references, the movement of the airspeed indications, as well as various changes in sound – but the relative differences between you and the rest of the contents of the airplane (including the suspended object) will reach the acceleration of the airplane. It is these kinds of relationships – and their changing over time – that are the basis on which the effectiveness of simulation is accepted … i.e., “just like the airplane.” Of course, a simulator does not (it cannot) accelerate continuously – but it DOES provide an on-set acceleration cue – and then reduces that on-set cue value at a rate that is below the threshold of recognition to the occupants. Simulators that used to have extremely poor motion cueing, did not do that – at least not very well, and sometimes not at all. In fact, I recall the Navy putting it’s A-7 pilots on a “do-not-fly” restriction for 72 hours (it might have been more, but I don’t think so) after having competed a “recurrent simulator training session” for that airplane at the Jacksonville NAS, Florida, in the mid-1980s. In fact, that particular simulator had extreme latency problems in a lot of its systems but particularly so in its motions systems.

The goal of simulation is to provide as many of those “on-set” motion cues as possible … then reduce them at a rate that is not recognized by the human body – and relying on the other cueing provided (visual, feel, and sound cueing presented just as would be seen, felt, and heard in the airplane) to verify to the simulator occupants that the acceleration is continuing just as you would have expected it to continue. Simulators with very long motion actuator legs are better able to do this than simulators with shorter actuator legs – which may be required by the structure of the facility or other limitations to that particular simulator installation. Electric motion systems (verses the older, but still used, hydraulic motion systems) are gaining in popularity due to its more immediate response, the greater amount of control it provides, less messy areas (hydraulic systems leak – and electrons don’t accumulate under the machine!) and do so with a shorter required actuator movement – and at an astonishingly low maintenance cost of only 20% of what a hydraulic system costs.

I’m not saying that a pilot should not be able to tell the difference between being in a simulator and being in the airplane. But – and it’s a significant “but,” the instructor and the simulator – together – should be able to provide any pilot a sufficiently accurate on-set cueing system (particularly that of motion on-set – or acceleration on-set) that will allow that pilot to learn what to feel in the “seat of his/her britches,” in coordination with what he/she sees, hears, and feels in the controls, to make a direct connection with the same (or very closely approximated) experience in the airplane. If we don’t do this – as a MINIMUM – what we’ll be doing is training and checking – both initially and recurrently – in a simulator – and then allowing those pilots to go fly something that is significantly different from what he/she was used to working with … and hope that these pilots “learn” sufficiently well, how to fly the airplane and then shift gears to demonstrate his/her ability in flying the simulator – and “never the twain shall meet.” THAT is what I am seriously concerned about. And, I can point to airline after airline, at least in the US, where THIS is exactly what is happening … training pilots in reasonably good simulators – or partially training them in such equipment, and then finishing the training and getting “checked” in a flight training device (which is even less like the airplane than a relatively poor simulator) and then not only allowing pilots to go fly the airplane, but expecting them to do so professionally and competently – when the training has been structured so as to engender activity unlike what is necessary to safely and competently operate their airplanes.

[glendalegoon]

I remember on a 737-300 sim, it was incorrectly set by the computer folk and it was like the engines were beyond the tips of the wings in terms of force and the rudder was not able to do the job. After the sim instructors couldn't control the plane the computer boys got to work and OOOPS.

They finally fixed it.

AS to the thumbs. When you lose an engine there is an almost imperceptible reaction by using ailerons to control the plane's initial yaw. Our instructors demonstrated that when you had both hands on the yoke, your thumbs pointed towards the side of the rudder pedal to be used. Give it a try.

V1 is called at V1 minus five at our airline. How about yours? Do your instructors turn down the engine sound (they can). With the engine sound up fully it can be your first indication something is wrong as the engines go out of sync.

SIMULATORS are just that, simulators. AT one time in our contract, a pilot could demand a check ride in the real plane and not a sim!

[AirRabbit]

I remember on a 737-300 sim, it was incorrectly set by the computer folk and it was like the engines were beyond the tips of the wings in terms of force and the rudder was not able to do the job. After the sim instructors couldn't control the plane the computer boys got to work and OOOPS.

They finally fixed it.

AS to the thumbs. When you lose an engine there is an almost imperceptible reaction by using ailerons to control the plane's initial yaw. Our instructors demonstrated that when you had both hands on the yoke, your thumbs pointed towards the side of the rudder pedal to be used. Give it a try.

V1 is called at V1 minus five at our airline. How about yours? Do your instructors turn down the engine sound (they can). With the engine sound up fully it can be your first indication something is wrong as the engines go out of sync.

SIMULATORS are just that, simulators. AT one time in our contract, a pilot could demand a check ride in the real plane and not a sim!


THE ENGINES WERE BEYOND THE TIPS OF THE WINGS: The situation you describe with your B737-700 simulator, if accurate, must have occurred “in-house” at some point AFTER the FAA had evaluated and qualified that particular simulator. And, in the off-chance that your simulator was/is located outside of the US, and was initially qualified by another national regulatory authority, I can confidently say that no regulatory authority in the world would allow such a configuration to go unchallenged and unchanged before completing the necessary qualification. That means that if this actually occurred, someone, probably within your company, who had access to that simulator, was “playing” with the programming and either set it up that way – or was unable to restore the original parameters. In addition, I simply cannot believe that any pilot, and certainly, any instructor, would not immediately stop whatever training or evaluation session was in progress, and point out the problem to competent technicians so as to make the necessary corrections. Such a situation would not be allowed to go beyond the initial recognition – and anyone who would, should have his/her pilot certificate examined for being counterfeit.

THUMBS: “When you lose an engine there is an almost imperceptible reaction by using ailerons to control the plane's initial yaw.” Of course this is true. The last time I checked ailerons controlled movement around the longitudinal axis of the airplane. When on the ground there is likely not going to be much “roll” around that axis before something unwanted happens. Also, during the takeoff roll, the amount of air over the wings is not consistent (of course!) and only when sufficient lift is generated will an asymmetrical lift (due to aileron displacement) provide any rolling moment. So far, we’ve not even touched on the direction of the airplane. Of course, any extension of an aileron surface into the air moving over a wing will result in some yawing moment (but it is more than likely that moment would be difficult to discern through instrumentation … let alone the “finely tuned hands” of a line pilot), and there would likely be a larger moment due to the “drag” (aft movement) of the wing with the “up” aileron than due to the “down” aileron – HOWEVER – that moment alone would not be TERRIBLY significant in any B737, and would be all but irrelevant when the airplane is still ON the ground during acceleration. During the initial portion of the takeoff, the rudder pedals (and NOT the rudder surface) has the “lion’s share” of control over the directionality of the airplane – and that through the nose wheel – controlled by nose wheel steering. As for the “thumb position” on the control yoke – once power is set, the non-flying pilot should be ensuring that no change in throttle position or power indication is allowed to occur so that the pilot flying will have both hands on the control wheel. The last time I checked, both hands have a thumb, and both thumbs would be on the inside of the control wheel – left and right – so it escapes me to understand how that might be an indication of what rudder pedal might be the appropriate one if a directional control problem were to occur. AND I know of NO competent instructor (perhaps it’s my definition of “competent” that is the issue?) who would even remotely consider using the position of one’s thumbs on the control wheel to be used as a “gouge” for whether the left or right rudder pedal was to be used to control a directional problem! I would whole-heartedly recommend that this idea be “round-filled” YESTERDAY!

V1 IS CALLED AT V1 MINUS FIVE AT OUR AIRLINE: I certainly cannot be the only person reading this statement and from that understands the level of dichotomy being presented. Again, if true, it is quite obvious that the person or persons who came up with this “not-so-splendid-adjustment” simply does not understand what V1 actually means and how it is derived. Making this kind of “adjustment,” particularly in such a broad and indiscriminate manner, may well have ramifications that are unknown until a catastrophe occurs … which, naturally, will be too late! I keep saying that we must stop trying to substitute a “cheat-sheet” method of operating an airplane. Airplanes were designed and from that a set of procedures were developed to allow the airplane to do what it was intended to do, and do it under the direct and continuing operational control of the pilot flying, and from that we developed procedures to teach others how to do what needs to be done to have the airplane do what it was designed to do. If we come along and attempt to substitute an alternative way – particularly if that “alternative” way has underpinnings of idiocy involved, we are moving farther and farther away from the “plumb-line” understanding (basic truth) of aviation. Just as JT opined earlier in this thread with respect to changing the way airplanes should be flown. He said … and he is absolutely correct:
Fly it like the ops engineering folk planned it or, else, get them to change the plan to fit the way you want to fly it.
If we go around making changes to the way an airplane was designed to fly without heeding JT’s very accurate comment, we are asking the forces of doom to visit us on a regular basis.

SIMULATORS ARE JUST THAT, SIMULATORS: Given the understanding that older simulators are not as well designed or simulate the airplane as accurately as do the more modern simulators, which I certainly do, I also believe that it is pure folly to categorize ALL simulators into a grouping with an understanding that all simulators are just like those designed, developed, constructed, and used, 3 or 4 decades ago. However, IF (and that word is getting lost as to its understood definition in many cases) but IF competent and well-trained instructors are used, even in those older simulators, even then, an adequate learning of necessary knowledge, duties, responsibilities, and skills can be achieved. Of course I advocate using such competent and well-trained instructors in ANY and ALL simulators to ensure that some stray thought or some short-circuited system does not contravene the designed understanding and ultimate operation of the airplane being simulated. The basic premise of the use of a simulator, instead of returning 7 to 9 decades in history, is that we can fly the simulator as we would expect to fly the airplane. The point that must be remembered – and it can be as accurate as we want to make it depending on the competency and professionalism of the well-trained simulator instructors – is that we always simulate in an airplane but we never simulate in a simulator. For those who immediately want to scratch you head in wonder over that statement … in an airplane we never actually “fail” an engine – we simulate doing it … we never actually land the airplane with the landing gear retracted – we simulate doing it down to a “safe altitude” … we never take an airplane into an actual bucking, kicking, rolling aerodynamic stall – we simulate doing it down to the stick shaker or initial buffeting … we never take off an airplane in a crosswind that is in excess of the demonstrated values – we simulate it … and the list can (and DOES) go on and on. However, in a simulator we don’t simulate any of that … we actually do it. And, particularly in the newer simulation equipment, validated with the newer flight test data acquisition systems and the facilities of electric control loading and motion systems, the newer dynamically accurate and field of view comparable visual systems, etc., what we have is an exceptionally close replication (trying to avoid the “S” word) of what would happen in an airplane. This is what simulation was intended to provide. However, and AGAIN, I point out the advantages of doing this in a simulator that has all of its limitations and characteristic competently known by the instructor using it. A simulator is precisely a simulator … and we all should be glad that they exist.

[misd-agin]

To me this is a disappointing thread. Going to the internet for answers isn't the optimum solution when they should be addressed by his instructor, training partner, or experienced pilots within his organization.

The OP talks about reducing pitch and getting to close to the ground. Being uncomfortable at 400', asking if he should reduce thrust, etc.

IMO there are multiple training issues, and deficiencies, that shouldn't be or can't be addressed without observation.

[john_tullamarine]

Going to the internet for answers isn't the optimum solution when they should be addressed by his instructor, training partner, or experienced pilots within his organization

Concur .. in an ideal world .. which doesn't exist.

Reality is that the general level of technical knowledge in the Industry is highly variable and a lot of folks who should know a lot more than they do .. simply don't.

The net always presents the problem of discriminating between competent advice and waffly garbage and, I guess, that will be the way it stays.

However, knowing the IDs of some of the folk who play in Tech Log .. I have to say that, were readers buying their professional advice out in the real world on a consultancy basis .. it would be costing a pretty penny.

If we were to list the technical degrees, doctorates etc., held by members of the group it would be a long list. Indeed, we have a number of folk who hold serious university professorial chairs .. one doesn't get their advice cheaply out in the real world and, here, we get it for free because they are interested in what we talk about.

Not for me to say who is who .. but, in general, the discriminating reader ought have not too much trouble sorting the wheat from the chaff. If something too silly for words gets put up for consideration, usually one of the competent folk will gently (and, sometimes, not terribly so) urge a more appropriate view ...

The relevant areas of PPRuNe, overall, offer a VERY valuable source of competent knowledge bases.

[misd-agin]

JT - I agree about the depth of experience and knowledge that's available, for free(!. )But the OP talks about reducing thrust while s/e to maintain a/c control right after takeoff. To me it appears that a basic understanding is missing, or perhaps weak, and the expertise available is behind the scope of the problem.

[john_tullamarine]

To me it appears that a basic understanding is missing, or perhaps weak, and the expertise available is behind the scope of the problem

.. and, were the expertise available in his own organisation, the problem ought to have been sorted out already. The fall back is resources such as PPRuNe.

It was the early (Vital 4 I believe) visual system effects, latency and bilious, cartoonish display that created that lingering dizziness and nausea.

Likewise, my first sim fun was in an early 727 which didn't match up all that well to the real McCoy. Not as bad as what you describe but the thrust is much the same. Visuals were best addressed by either not looking or closing one's eyes and working it via Braille.

[glendalegoon]

air rabbit

WHY would I make up anything like this?

The callout of V1 is to start at V1 minus 5 knots to ensure that the call is complete by V1. And our airline got this from boeing.

AS to the simulator problem in the 737-300, it was in the USA, it did happen and they fixed it. Imagine that, a technical problem with a high tech gadget. And at the time, the 737-300 was a new plane.

THE thumb thing works when you are airborne , not so much on the ground. But on the ground if you are ''visual'' you can see yaw as the plane heads towards the weeds without correction.

[AirRabbit]

WHY would I make up anything like this?
That is the same question I had ….

The callout of V1 is to start at V1 minus 5 knots to ensure that the call is complete by V1. And our airline got this from boeing.
What?! “…to ensure that the call is complete by V1?” How long does it take to say “V-One?” If I were told to do that by one of my company managers or instructors, I would politely ask to see the note or the bulletin in which that recommendation is included. I know a lot of folks at Boeing … and to my knowledge none of them would make that kind of recommendation.

AS to the simulator problem in the 737-300, it was in the USA, it did happen and they fixed it. Imagine that, a technical problem with a high tech gadget. And at the time, the 737-300 was a new plane.
“High-tech gadgets” and “full flight simulators” are light-years apart in so many different understandings – I am a loss to provide a comparison … and, many here would be shocked to hear me say anything like that! However, having said that, of course, during the initial design and build process of almost anything new – particularly something as complex as a computer version of an air transport category airplane, some kinds of errors will inevitably creep into the process. But, as you describe the airplane as “new,” it would have to have been sometime between mid-1985 and probably the start of 1987 … I know the last deliveries of this airplane were sometime during late 1998 – 1999 time frame. So, the simulator would likely have been ordered / built / delivered / tested (in that order) starting perhaps as early as the end of 1985 … so delivery and FAA evaluation would likely have taken place around 1988 – 1990. By that time, I know several simulator manufacturers that had orders for and had delivered quite a few of what, at that time, was known as Phase III simulators (that same level is now called Level D) and I know that the first Phase III simulator ever ordered was for a B737-200 from a manufacturer in the UK named Rediffusion in 1982 … this manufacturer later became known as Redifon Flight Simulation – and the visual manufacturing portion remained in business for some time after the parent company became part of Thales. There were a lot of hurdles that had been jumped during that order/manufacturing process – not without some skinned knees, but those were generally due to first-off circumstances and once understood had been substantially overcome for subsequent orders. Given this understanding, it sounded, to me at least, that having such a sophisticated piece of machinery delivered with such basic programming errors of such a magnitude as you described … is so far off the charts as to sound … well, suspicious.

THE thumb thing works when you are airborne, not so much on the ground. But on the ground if you are ''visual'' you can see yaw as the plane heads towards the weeds without correction.
I was under the impression that you were discussing takeoff rolls and certainly engine problems on the ground and in the air are different – have differing causes – and have differing choices regarding how to react. Again, operating in 3-dimensional space can be “simulated,” but only up to a point – and, while I may be somewhat prejudiced as to how well its done today – there are many who have seen and flown such simulators that are absolutely convinced that these machines are, in fact, the ONLY way, and the BEST way to train and check pilots. As I’ve maintained for sometime now, I continue to urge that ALL simulators be used under the direct observation and control of a specifically trained, competent, and knowledgeable flight instructor or evaluator. Having said this, engine failures on the ground or in the air can be very realistically simulated in modern full flight simulators – and provided simulator sessions are overseen by the kind of instructor / evaluator I have described, they regularly result in an exceptionally well trained and competent aviator. This is the specific reason that I keep harping on having the simulator provide as much on-set cueing information to the flight crew – as close to what the airborne airplane will provide – and is the only way we can train a crew member to perform the same in training as we expect during on-line operations. We cannot accept a pilot with 2 skill sets – one that is focused on how to successfully operate a simulator … and one that is used to fly airplanes … i.e., not trained, not observed, not evaluated, but accepted because the regulator qualified and approved that simulator for training and testing. That is a formula for failure.

[AirRabbit]

(The A-7 sim didn't have a motion system, just a 'G' seat. It was the early (Vital 4 I believe) visual system effects, latency and bilious, cartoonish display that created that lingering dizziness and nausea. ANG rule was you just couldn't fly the same day after a sim session, but ANG guys were tougher than the USN types. )

Hey OK465:

As memory serves (…and I’ve often complained that it doesn’t do that very well any more…) that A-7 “sim” was, indeed, a “piece of work." I was one of the “outsider participants” that was asked to come take a look at this machine … I don’t recall any specific concern with the overall quality of that machine, and don’t recall anything specific about the visual scene content, even though VITAL 4 (which stood for “VIRTUAL TAKEOFF AND LANDING”) was, at that time, a pretty “standard” fixture in the world of simulation. What actually stands out is my vivid memory of the latency numbers we found between control input and visual system response. A poor simulator at that time had latencies of between 500 and 600 milliseconds …this one was easily twice that and at times pushed 2.5 times those “poor system” values! That’s almost enough time to make a control input, go to lunch, and return in time to see the visual respond! No wonder the guys got sick!

...and I'll pass along your comments to my Navy buds for their enjoyment (?!) ... as I was a "blue suiter" myself.

[glendalegoon]

REGARDING the V1 call being started at V1 minus 5. I assure you this is the case at my rather large airline. It has been the case for many, many years.

AS to the paperwork supporting it, I've long since thrown it away as it has been on every sim ride for at least 15 years and possibly more.

I see the need for it and the rhyme and reason are very clear. I don't know anyone at boeing, but the people who sign my checks said they got it from boeing. Our airline has many boeing planes and I have no reason to doubt my airline. And thousands of our pilots do it that way.

AS to the simulators, calling them high tech gadgets is like calling a cute girl a bird. It is a bit of slang.

AND as you say, the offending simulator was coming online circa 1987/88. I don't even think we were saying online back then in the same context.

THE whole point of this thread was to help a new pilot to fly a very old plane and old simulator.

LETS ask the original poster if anything did help him pass his checkride.


OH, I further researched the V1 minus 5 business. Did an online search. Found a PPRUNE thread from about a dozen years or so ago. READ the last post.

V1 or V1 minus 5kt callout? [Archive] - PPRuNe Forums (http://www.pprune.org/archive/index.php/t-65341.html)

[AirRabbit]

THE whole point of this thread was to help a new pilot to fly a very old plane and old simulator.
I do understand what occurs with reading and posting on this particular aviation forum – and I certainly agree that some of us learn things that we would never have guessed in a thousand years! That doesn’t immediately mean that we agree with all that is posted – by a long shot. The idea that I’ve always tried to convey – is that proper use of simulation can (with specifically accomplished goals) actually and effectively teach pilots how to manage an airplane throught he myriad of conditions seen in airline operations today. Almost 35 years ago, it became clear that both the airlines and the regulators could – in certain circumstances – accept the use of such training equipment in lieu of requiring everything to be done in the airplane. As I’ve said many times here … when using the airplane, the first 5 or 6 responsibilities of the instructor have nothing to do with training the student – and only AFTER all those other requirements have been satisfied can the real reason for everyone being on board in the first place gets to happen … training. Conversely, when using a simulator – the only thing required is to train the student … period!

However, there were some caveats that were laid out and as technology improved over time, those caveats began to be met more readily … and this continued to improve until the development of Part 121, Appendix H, and the associated Advisory Circular – that clearly, and for the first time, allowed ALL of the training AND the check of a pilot to be accomplished and completed in a qualified airplane simulator. The first time the pilot actually saw the airplane (in many cases anyway) he/she was involved in obtaining his/her line operating experience with passengers on board. That was in June of 1980. We’ve come some 34 years now and in during this time the “knowledge generation” has been reduced from about 8-10 years to 8-10 weeks! Of all the simulators that have ever been qualified and used in the US – and there have been almost 1400 since mid-1980, but the fact that there are only a whisper more than 800 of these devices currently active means that almost that number have fallen by the wayside in those years.

I say all of the above to say … in response to your comment quoted above … as most of the “regulars” here can attest, my “hot button” issue is the development of “cheat sheet” short cuts to satisfy the requirements that are often watched and signed off in a simulator. I’ve seen so many “cheat sheet” suggestions that “seem to work” in the simulator – having absolutely nothing to do with how the airplane should actually be flown – but fool the inattentive or ill-trained instructor or evaluator that we run the risk of admitting good “slight-of-hand” artists – who “talk” a good game, and have “demonstrated their ability” through the use of a set of canned numbers and suggestions to “get through the simulator session” – that I’m beginning to fear for the safety of the industry. I’m not interested in what appears to work in the simulator that looks good to an observer. I’m interested in using these devices on the basis that these devices provide identical “on-set cueing” information that is just exactly like what would be recognize in the airplane under the same conditions … that the simulator performs and handles “just like the airplane” in similar circumstances. There are some simulators that do this regularly – but the point is that even with the oldest simulator in the industry, if the instructor is properly and completely trained and pays proper attention to his/her students’ actions while operating the simulator, that student should be able to learn exactly what the airplane will do and learn exactly what he/she must do in response. Anything less does not do anything but jeopardize the safety of anyone flying with those person(s). The only way to do this and do it regularly is to have simulators that perform to the standards that have been agreed upon and for instructors and evaluators to expect identical performance of the student/examinee … just as would be expected were it all to have been done in the airplane. Finding ways around the programming or fudging the fact that a simulator does not really “fly,” and give the impression that all is good – is, in fact, not good and very easily could be catastrophic in the most negative manner possible. And, if I had to, I could point out case after case, after case where this is clearly evident. That is the reason I participate on these forums – not to toot my horn or have people be “in awe” of my brilliance … that is why I remain anonymous … THAT is not my goal … competency in the cockpit is my goal … and that is the reason I participate here – and I thank JT for the opportunity … probably nowhere near often enough.

[AirRabbit]

OH, I further researched the V1 minus 5 business. Did an online search. Found a PPRuNe thread from about a dozen years or so ago. READ the last post.

OK – I read the post – and I disagree with the suppositions and the arguments made. I’ll go ahead and post the full section of the rules that describe “Takeoff Speeds.” It surely addresses the issues of importance … and probably goes farther than you’d care to read … but as you can see there is no 2 second timing kinds of things in the rules…

Each of the “V speeds” that the regulations require be computed have a specific reason, that must be taken all together to ensure that if all things turn out to be as expected, the airplane can be safely taken off if all of those parameters are met.

14CFR part 25 §25.107 Takeoff speeds.
(a) V1 must be established in relation to VEF as follows:
(1) VEF is the calibrated airspeed at which the critical engine is assumed to fail. VEF must be selected by the applicant, but may not be less than VMCG determined under §25.149(e).
(2) V1, in terms of calibrated airspeed, is selected by the applicant; however, V1 may not be less than VEF plus the speed gained with critical engine inoperative during the time interval between the instant at which the critical engine is failed, and the instant at which the pilot recognizes and reacts to the engine failure, as indicated by the pilot's initiation of the first action (e.g., applying brakes, reducing thrust, deploying speed brakes) to stop the airplane during accelerate-stop tests.
(b) V2MIN, in terms of calibrated airspeed, may not be less than—
(1) 1.13 VSR for—
(i) Two-engine and three-engine turbopropeller and reciprocating engine powered airplanes; and
(ii) Turbojet powered airplanes without provisions for obtaining a significant reduction in the one-engine-inoperative power-on stall speed;
(2) 1.08 VSR for—
(i) Turbopropeller and reciprocating engine powered airplanes with more than three engines; and
(ii) Turbojet powered airplanes with provisions for obtaining a significant reduction in the one-engine-inoperative power-on stall speed; and
(3) 1.10 times VMC established under §25.149.
(c) V2, in terms of calibrated airspeed, must be selected by the applicant to provide at least the gradient of climb required by §25.121(b) but may not be less than—
(1) V2MIN;
(2) VR plus the speed increment attained (in accordance with §25.111(c)(2)) before reaching a height of 35 feet above the takeoff surface; and
(3) A speed that provides the maneuvering capability specified in §25.143(h).
(d) VMU is the calibrated airspeed at and above which the airplane can safely lift off the ground, and continue the takeoff. VMU speeds must be selected by the applicant throughout the range of thrust-to-weight ratios to be certificated. These speeds may be established from free air data if these data are verified by ground takeoff tests.
(e) VR, in terms of calibrated airspeed, must be selected in accordance with the conditions of paragraphs (e)(1) through (4) of this section:
(1) VR may not be less than—
(i) V1;
(ii) 105 percent of VMC;
(iii) The speed (determined in accordance with §25.111(c)(2)) that allows reaching V2 before reaching a height of 35 feet above the takeoff surface; or
(iv) A speed that, if the airplane is rotated at its maximum practicable rate, will result in a VLOF of not less than —
(A) 110 percent of VMU in the all-engines-operating condition, and 105 percent of VMU determined at the thrust-to-weight ratio corresponding to the one-engine-inoperative condition; or
(B) If the VMU attitude is limited by the geometry of the airplane (i.e., tail contact with the runway), 108 percent of VMU in the all-engines-operating condition, and 104 percent of VMU determined at the thrust-to-weight ratio corresponding to the one-engine-inoperative condition.
(2) For any given set of conditions (such as weight, configuration, and temperature), a single value of VR, obtained in accordance with this paragraph, must be used to show compliance with both the one-engine-inoperative and the all-engines-operating takeoff provisions.
(3) It must be shown that the one-engine-inoperative takeoff distance, using a rotation speed of 5 knots less than VR established in accordance with paragraphs (e)(1) and (2) of this section, does not exceed the corresponding one-engine-inoperative takeoff distance using the established VR. The takeoff distances must be determined in accordance with §25.113(a)(1).
(4) Reasonably expected variations in service from the established takeoff procedures for the operation of the airplane (such as over-rotation of the airplane and out-of-trim conditions) may not result in unsafe flight characteristics or in marked increases in the scheduled takeoff distances established in accordance with §25.113(a).
(f) VLOF is the calibrated airspeed at which the airplane first becomes airborne.
(g) VFTO, in terms of calibrated airspeed, must be selected by the applicant to provide at least the gradient of climb required by §25.121(c), but may not be less than—
(1) 1.18 VSR; and
(2) A speed that provides the maneuvering capability specified in §25.143(h).
(h) In determining the takeoff speeds V1, VR, and V2 for flight in icing conditions, the values of VMCG, VMC, and VMU determined for non-icing conditions may be used.

[glendalegoon]

air rabbit:

I mentioned that my airline (and it seems many others according to the link to an archived pprune thread)starts the V1 call at V1 minus 5.

THIS procedure has been in use for many years. THE FAA could have unapproved it, but has not.

AND while it is very nice of you to make your post, I do not anticipate anything changing.

I remember what a big deal it was when it first came out. AND it came out last century.

I AM NOT making an argument for or against the use of this way of calling V1.

BUT it is the way that many airlines do it.

AND unless you buy my airline and change things (which would involve paperwork galore) I shall continue to say V1 starting at V1 minus 5.

JUST in case something had changed at my airline in the last day or so, I called a training captain and explained the discussion I was having on PPRUNE. He confirmed that nothing had changed and it was still V1 minus 5 to start the callout.

HE had some choice words for you, which I shall not post here out of respect for forum rules.

[Junkflyer]

The FAA defines V-1 as the speed the maximum speed at which the takeoff maneuver can be initiated and the airplane stopped within the remaining field length under the conditions and procedures defined in the FAR's. Also the "go procedures, but this does not apply this particular discussion.
It has changed from a decision speed to an action speed. My airline teaches the V-1 call at V-1 minus 3 knots in order to initiate an abort by V-1.You can go to Faa.gov and search "takeoff safety" or go/no go decision. Way too much to post here, but full of good info.

[Centaurus]

Re simulator fidelity checks where scheduled checks may include engine failures during and immediately after take off. Normally the test crew includes technicians and qualified on type flight crew.

I have often wondered how an engine failure during a fidelity check can be assessed as like the real thing when the assessing pilot may never have experienced a real engine failure on take off in the type of aircraft he is assessing. How valid therefore is this assessment in terms of fidelity? Or is it a case of tongue in cheek "seems OK to me" assessment?

[AirRabbit]

The FAA defines V-1 as the speed the maximum speed at which the takeoff maneuver can be initiated and the airplane stopped within the remaining field length under the conditions and procedures defined in the FAR's. Also the "go procedures, but this does not apply this particular discussion.
It has changed from a decision speed to an action speed. My airline teaches the V-1 call at V-1 minus 3 knots in order to initiate an abort by V-1.You can go to Faa.gov and search "takeoff safety" or go/no go decision. Way too much to post here, but full of good info.

You said “it (the definition of V1) has changed from a decision to an action speed,” but that is not completely accurate. It is still a decision speed. The decision is whether to continue the takeoff or reject the takeoff. Most references define V1 as the takeoff decision speed. It is the speed used by the pilot which satisfies all safety rules; meaning that if an engine failure is experienced at that speed, and the decision is made to reject the takeoff, there will be sufficient runway remaining in which a safe stop may be made; OR, if the decision is made to continue the takeoff, there is sufficient runway remaining to continue the takeoff and achieve the required height above the takeoff surface within the takeoff distance.

Generally, the way this is described is that V1 may not be less than VEF (this is the “critical engine speed”) plus the speed gained with that critical engine not operating during the interval of time between the engine failure and the pilot recognizing the engine failure (marked by when he/she takes the first action to either continue or to reject the takeoff). Obviously, it is important to know, and to know how to deal with, this particular term (i.e., V1)

However, this doesn’t necessarily become a critical issue until we start discussing the balanced field concept. In other words, if you were on one of the dry lake beds in the western US, you could theoretically take a nap between an engine failure and doing something about it – and it wouldn’t matter – safety wise. But on a runway with finite dimensions, you want to be able to get stopped, if you choose to stop, before you run out of runway … or you want to be able to get airborne, and be able to achieve the minimum altitude at the appropriate point (i.e., the takeoff distance ... and there is a specific definition for this term as well that I would recommend anyone really interested in this discussion take a moment to read) if you choose to go fly.

It’s not so much that I feel a need to argue about 2, 3, or 5 knots with respect to what V1 actually is and when it is “called,” because of where most airline operations take place today … that is, most (and I emphasize, MOST) of the airports where airline operations regularly occur, there has been some reasonable care taken to provide an excess of runway for most situations. But you and I don’t necessarily have all that information available to us … and to ignorantly change a procedure or alter a standard, is, in my not-so-humble opinion, balancing on the edge of the “stupid-cliff” – and just may result in falling into that chasm of “stupidity.” But, as I keep mentioning, I think what “irks” me most is when individuals begin to take liberties with what the rules say and either re-interpret them or completely disregard them. I’ve always operated under the concept that someone, someplace, set up the definitions and procedures for a reason. IF that reason no longer exists … fine … describe what is different … change the definition or the procedure … and explain why the new definition or procedure makes sense. IF someone just doesn’t like to have to comply with a definition or a procedure – which does happen – although most of the time this occurs it’s when someone hasn’t seen the conditions for which the definition or procedure was created for some time, they may feel that complying with any restriction is no longer valid. If it IS true that the definition or the procedure mandated is no longer valid … again, fine … explain what has changed and change or eliminate the definition or procedure. But regardless of the issue … I object to simply ignoring or changing what was established – regardless of the intention involved.

HE had some choice words for you, which I shall not post here out of respect for forum rules.

Glendalegoon – First … I’m quite sure that JT would thank you for your discretion … and second, I’m beginning to suspect that you have your head screwed on pretty darn straight and want to do the right thing – and if I came on a bit strong in the opposite direction – please know THAT wasn’t my intent. I understand the importance of not deviating from company procedures and I certainly wouldn’t condone ANYONE deviating without discussing the “whys” and the “whens” and the “hows” to everyone’s content. I’m glad that you called your training representative … even though I’m disappointed in his apparent disdain for what I’m trying to say. I would have hoped he would have at least examined what I was saying and figured out why I was saying it … but, no matter. He, or anyone else, can take a bite out of my backside anytime they choose … but I would assure him that he’d only get a mouthful of scar tissue!

[glendalegoon]

air rabbit

I've now found data indicating the five knots before rule was first mentioned almost 20 years ago.

The reality of flying is sometimes different than the engineering of flying.

PEOPLE are involved with flying and that makes it a bit of an art as well as some science.

My training guy did review what you said. Perhaps you should review all that stuff junkflyer mentioned. After all if you wait until V1 is indicated on the ASI then you are finishing the words V1 after V1 has been exceeded.

YOU mentioned something about runways with margins. I can think of too many with less than generous margins here in the USA. And I think the reality of those airports lead to our way of doing things.


I do imagine a peer review journal might enjoy your writings.

[AirRabbit]

I've now found data indicating the five knots before rule was first mentioned almost 20 years ago.
The reality of flying is sometimes different than the engineering of flying.
PEOPLE are involved with flying and that makes it a bit of an art as well as some science.
My training guy did review what you said. Perhaps you should review all that stuff junkflyer mentioned. After all if you wait until V1 is indicated on the ASI then you are finishing the words V1 after V1 has been exceeded.
YOU mentioned something about runways with margins. I can think of too many with less than generous margins here in the USA. And I think the reality of those airports lead to our way of doing things.
I do imagine a peer review journal might enjoy your writings.

Obviously, my providing any additional information or justification or explanation isn’t going to change your mind on this … and the same very likely holds true of some who participate here ... and I recognize that fact. So … let me conclude this exchange with the following observation … and caution … for whatever its worth.

Calling out “V-One” at a point 5 knots prior to the actual “V1” would not present a performance problem IF the decision to either reject or continue is always made in the favor of rejecting the takeoff. Why do I say that? If the engine were to fail at precisely the same moment as the “5 knots early” call of “V-ONE,” and the pilot flying immediately decided to reject by taking the necessary steps … simultaneously closing the throttles, exerting maximum pedal pressure on the brakes, and as soon as the throttles are snapped to the idle position, immediately grabbing and extending the ground spoilers, all while maintaining directional control through the rudder pedal steering, if necessary, backed up with a hand on the nose wheel steering controls … there is little doubt that the airplane could be brought to a stop within the confines of the runway. In fact, it probably would come to a stop at a point somewhat short of the distance shown by the “trace-around-charts” – which we rarely see anymore.

However, if the pilot flying were to decide differently … that is, decide to continue the takeoff … the airplane would have to continue accelerating without the thrust that would have been provided by that now-failed engine. Believe it or not, that is a LOT of lost thrust. That means that with less thrust to accelerate to the same rotation/takeoff speed, the takeoff roll would be some distance longer than originally planned, meaning that the airplane would become airborne somewhat later in the takeoff sequence … meaning that the now-reduced takeoff flight path would be moved further into the obstruction clearance pathway … which means that what had been a relatively obstruction-clear pathway may not (notice I did not say “will not” … I said “MAY not”) exist. Is that something to be concerned about? Probably not – at least not under a good share of the circumstances … but if this function can be cavalierly dismissed … what other “hard-n-fast” rules and regulations may also enjoy some level of relaxation?

Yes, we do have a procedure that the pilot monitoring will call out the appropriate numbers … well and good. But the vintage of pilots from which I come, would be hard pressed to NOT know themselves – without any input from anyone else in the cockpit – whether the airplane was accelerating normally or not – through both physical sense and knowledgeable reference to the airspeed indicator … and know when he/she had reached that magic number, V-One, without having to be told. In today’s vintage, if the guy/gal in the other seat didn’t call out “V-One,” I’m not at all sure that the pilot actually flying the airplane would have any idea about when the airplane had accelerated to that point.

The designation of “V-One” was developed to avoid a circumstance where an engine failure occurring at the most critical point on the takeoff roll and presenting an exceptionally difficult conundrum for the pilot (do I stop or do I go). A specific number was decided to be used – not the number, but what it represents – that being the division point that gives the pilot the best opportunity to make the correct decision … continue or stop. However, now we’re discussing the movement of that decision point – and this decision is based on … what? As I said it would provide for a better outcome if the decision was to “stop,” but I’m not at all sure that it would provide for a better outcome if the decision is to “go.”

As you’ve said – there may be far too many airports out there with "less than generous margins" - which, in my mind, should generate more, not less, concern about such a decision ... and should encourage additional discussion on this ... not abject silence. I believe that it should be considered a bit more seriously ... but, again, what could I possibly know? Well, I tried, but ... as you've said ... it’s not my airplane ... it’s not my airline ... but it also won’t be me on the witness stand.

My hope is that you have a very successful and safe career … and I’ll leave you with recalling a very famous line in a very old TV series … “choose wisely grasshopper.”

[glendalegoon]

air rabbit

please review post 33. the v1 call is begun at five knots prior so as to complete the call by v1.

our airline has been doing fine since we started this procedure.

I encourage you to write for a peer reviewed journal. Perhaps the FAA will follow your lead. But right now, boeing, and the major airlines are doing it pretty much like I have written. AND THEY DO IT WITH FAA approval.

I've looked at the concept three ways till sunday and am in favor of it.

[AirRabbit]

glendalegoon:

I don’t normally continue an “on-line” discussion such as this with someone who has convinced me that he (or she) isn’t going to agree with my point of view … no matter what … but frankly you have impressed me with your tenacity and your determination (demonstrated by calling your training resource – which I think I said I admired) have got me to a point where I think it appropriate to offer one last “tid-bit” of information.

Some time ago, a group of aviation professionals were assembled into a multi-participant group, sanction by and participated in by the FAA, and quite a few airlines, airline organizations, pilots and pilot organizations, training organizations, and Airbus Industries, Boeing, and McDonnell Douglas … the later three of whom contributed performance data relating to rejected takeoffs. While the topic was Takeoff Training Safety – the primary thrust was clearly aimed at eliminating, or at least reducing the numbers of takeoff accidents occurring due to the improper actions of pilots – the vast majority of such accidents/incidents were due to rejecting the takeoff for various reasons, at various points along the takeoff runway. In case anyone is interested … for a fee, this document, called The Takeoff Safety Training Aid, a 298 page document, that goes into about as much detail as anyone could ever want (not much of an exaggeration … if any!) about takeoff issues, may be obtained by the general public from the National Technical Information Service (NTIS), 5285 Part Royal Road, Springfield, Virginia 22161, and for those of us with slightly shallower pockets, a Portable Document File (PDF) version of this document may be obtained from various sources on the internet.

This particular document was devoted to eliminating or at least reducing the number of takeoff related accidents and incidents. As such, there are sections that deal with things like “takeoff call-outs.” As such, this document describes the necessity of the pilot flying the airplane to include airspeed in his instrument scan during the takeoff ground roll, citing the fact that “…the pilot flying cannot react properly to V1 unless the V1 call is made in a timely, crisp, and audible manner.” In fact, this document references a US airline who had suggested “completing the V1 callout by the time the airplane reaches V1 – which, I take, was likely your airline. This reference is described as a means for helping to ensure that “…a decision to reject the takeoff is not made after V1 – which could be disastrous on some runways.” However, this document goes on to say that others have recommended calling out “Approaching” as the V1 speed is approached and then calling out “V1” as the airspeed reached the actual V1 speed. If a direct and simple “V1” call-out at the proper speed is, somehow, thought to be insufficient – for whatever reason – (even though its seemed to have worked well for a number of years) then I’d recommend this alternative!

Again – as I think I’ve indicated – IF (and please don’t disregard the contingency reference) if the focus is on initiating an RTO and completing it successfully –certainly calling out “V1” at a point prior to the actual V1 speed would certainly provide adequate runway in which the RTO could be completed successfully. BUT – as I’ve attempted to point out, if this is the intent, and something does occur in that region between the “approaching” call-out and the actual “V1” call-out and pilot flying confuses something said by the non-flying pilot with that pilot having called out “V1,” and the result is a decision to continue the takeoff – the circumstances certainly COULD lead to a dramatically unwanted result. Call me negatively fatalistic if you desire but given the opportunity for something to go wrong – what do you think the odds are that someone will do precisely what was NOT intended? And in the realm of airplane and airline operations, that is something I would go to great lengths to avoid.

OK … my friend … fly safe.

[glendalegoon]

LETs say you decide to continue a takeoff three knots prior to V1...what could happen. Your screen height might be 30 feet instead of 35 feet. It might be 20 feet instead of 35 feet.

LETS say you decide to abort the takeoff 3 knots after v1, you might end up in the harbor.

[Killaroo]

Sorry Air Rabbit, but I have to agree with GlendaL here.
32 years in a euro flag carrier. We adopted that -5 callout decades ago, while still an all Boeing operator. We were told it was for the same reason Glenda just described - they preferred us to be GO oriented, especially on those short runways. The industry statistics seem to back up the philosophy too. Many more accidents seem to occur as a result of rejected take-offs than with taking the problem into the air and sorting it out.
Technically I can see exactly what you're saying, and it's all technically correct.
Operationally, things aren't always so clean and 'textbook'.

By the way - we went Airbus, and they have made it all moot now by having an auto callout at V1.

[Mach E Avelli]

The OP at his post #16 mentions that his simulator tormentor is 'failing' an engine at V1 minus 5 to 10 knots, but he is attempting to continue the take-off and losing control. As he appears to only have about 250 hours experience, it is not surprising that the combination of a cranky old simulator, instantaneous total loss of thrust on one side with probable rated thrust on the other, and poor visuals are conspiring against him.
With such low-time students I would be cutting them some slack by introducing any failures sufficiently below V1 to make it clear to reject the take-off. About minus 10 to 15 knots at the latest. Otherwise I would be waiting to hear the "V one" call from the support pilot before pushing the big square 'fail' button on the console. If that call was unreasonably early, or late, it would be time to freeze the box and have them agree to call it at exactly the number bugged. Surely the object at this early stage of training is to set clear parameters and not to confuse by flying around in some twilight zone?
Whether a company's SOP wants it 2, 3 or 5 knots early is for the line training people when he gets the job. If he already has the job, that should have been sorted out prior to commencing simulator.


PS: 3 knots is about the thickness of the white bug on the old ASIs fitted to most Jurassics, and those ASIs aren't all that clinically accurate anyway. In the real aircraft (not sim!) it's not unusual for there to be a 3 knot split between sides. So on a limiting runway it really depends on how you read your ASI.....Calling V1 a smidge early can't hurt, SOP or no SOP. By a 'smidge' I mean about 3 knots, which lacking any suggestion of calling early in the standard Boeing SOP, is within a reasonable range of reading error and will certainly ensure that the call has been completed by actual V1.

[bubbers44]

We were about to take off at San Jose Costa Rica one day in a B727 and it was an upslope runway heading into terrain so an early right turn was required. It is over 3,000 ft elevation and was a warm day.

I mentioned to the FO we were close to balanced field length because of our weight. He said that is ok because the other captain I have been flying with just sets V1 10 knots low. I said but that is illegal. He said, no it really works. I asked him if they ever aborted. He said no. I said what if you call V1 10 knots slow and I continue the take off, will I meet our climb requirements? No answer.

Why not just stay legal, it makes the hearing go so much better.

[AirRabbit]

Well, to me, at least, it appears that some here are confusing calling “V1” at the correctly determined V1 speed with calling “V1” at something less than the correctly determined V1 speed – where the specific amount less than V1 to be individually determined by um … each airline? each fleet Captain? each Captain? each pilot? each what? And, the reason given for deciding on which of the above options is the appropriate choice is that the airline is “Go oriented” …really? I think that the post by bubbers44, above, (thanks bubbers) might bring at least some doubt into that conclusion.

This MAY come as a surprise to some here, but “calling out” anything during the takeoff roll is, in itself, totally meaningless. The issue here is to “call out” something meaningful at a very specifically identified airspeed … but not just any airspeed … an airspeed that is very specifically identified with the performance of that airplane, on that date, at that time, at the existing environmental conditions, at that gross weight, on that runway (with all of what that implies – gradient up or down – obstacles off the departure end – etc., etc.) all with a very specific thought in mind – whether or not to reject or continue the takeoff. Of course there are several events that might lead a flight crew to decide that it is not prudent to leap into the air – but that is entirely related to what event occurs and when that event occurs. Not all events are equally impacting on airplane performance and each event is not necessarily noticed as quickly as the other events. Obviously, the event that is the most notable is very likely an engine failure (at least that is the conclusion reached by the group that developed the Takeoff Training Safety Aid, described in my most recent post) – it is also likely the most performance affecting. The other events may or may not eventually lead to an engine failure, but if they were to occur when a rejected takeoff could be safely accomplished on the runway remaining, a rejected takeoff is probably the more appropriate course of action to take.

Of course, if an engine failure event were to occur within the same boundaries, i.e., enough runway remains in front of the airplane such that a rejected takeoff could be accomplished safely, logically, that would remain the more appropriate action to take. This is precisely why most airlines today have a pre-takeoff briefing that includes a review of what events would be cause for rejecting the takeoff. However, I think it appropriate to point out the fact that as we’re discussing whether or not to continue a takeoff alone implies the potential necessity to perform a rejected takeoff. In that we’ve pretty much decided on the “what” part of the concern, the next issue for consideration is, “where” would it be most appropriate to make such a decision? Obviously, that is directly dependent on the location of the airplane on the runway when this decision is made … is there enough runway left to stop … is there enough runway left to continue the takeoff?

There are some here who state “…Calling V1 a smidge early can't hurt, SOP or no SOP. By a 'smidge' I mean about 3 knots, which lacking any suggestion of calling early in the standard Boeing SOP, is within a reasonable range of reading error and will certainly ensure that the call has been completed by actual V1.” (Mach E Avelli) It is my impression that this statement is likely based on what we all recognize as the almost impossible task of calling out the precise time, to the second, if you plan to clearly say “3:15:45” when the second hand clicks to the “45” position; this is because by the time it takes to say each of those words, it’s likely already “46.” Granted. But IF there was an understanding that the time of “3:15:45” would be “called” by having the time-watcher saying, out loud, the word “NOW,” there is nothing that would preclude that time-watcher to say “NOW” just as the second hand clicked to the “45” position. Of course, if an airline wanted the airspeed “watcher” to be precise in calling out when the A/S reached a very precise number (and I have problems with the idea that one of the pilots’ eyes would be “glued” to the A/S indicator, but…) and, what is to be said is “You are now at V1 speed” or even a more simple statement of the specific airspeed, such as “One-thirty-two,” the same kind of argument could be made. But, as the call-out is a succinct “V-One,” I cannot see how the “exact-time-impossibility” argument can be used – at least with what I would call any credibility. If there is a built-in error in the A/S indications (which is a topic for an entirely different discussion) isn’t having such a known error already enough of a compromise? And if there is any question, please go back and re-read bubbers44, comment above. Obviously, that F/O recognized that calling V1 early, with those existing conditions, indicating that a problem, like an engine failure, occurring after that call, where it would be thought to be “too late” to reject, pretty much demanding that takeoff proceed, while recognizing that continuing the takeoff under the conditions cited, now with an engine inoperative, very well could have led to a very objectionable and unsatisfactory result.

As I’ve said (and some would say too many times) on this forum … I am opposed to making adjustments to prescribed procedures because it looks to be an appropriate way to “make it work” and relieve someone from having to perform as they were expected to perform. I’ve called those “cheat sheet” methods to accomplish something. Is this another “cheat sheet” issue? Is this particular issue so close to the edge that it makes a significant difference … apparently not. As anyone would recognize – airplanes and their engines do not always operate in accordance with the book descriptions. But does that give us the logical recourse to do something that “seems to work,” “works in the sim,” or some other “almost logical” reason? How close to being flat wrong does something have to be before it is recognized as being wrong? It is apparent that there are those here who have “called” V1 at a point well prior to the actual V1 – and have done so without any problems … at least, so far. Does that make it right? I think each of us is going to have to make those kinds of decisions either on our own or with some responsible party's recommendation or edict. The regulations sound pretty clear to me. Are these regulations right? Should they be changed? There seems to have been a rather major effort to determine what, if anything should be done – reference the Takeoff Training Safety Aid document. So, what do we do now? I know what I’m going to do. It seems that our colleague bubbers44, had it pretty much nailed when he said “Why not just stay legal, it makes the hearing go so much better.”

[Junkflyer]

http://www.faa.gov/other_visit/aviation_industry/airline_operators/training/media/takeoff_safety.pdf

[Junkflyer]

This is from the Faa.gov website. V-1 means initiate the reject (or not) at this point in time. A half second later you continue and fly the airplane on the remaining engine(s)

[Junkflyer]

BTW my company reduces the runway length on all computations by 1,000 feet. It is an additional safety factor to add another margin of safety.

[AirRabbit]

V-1 means initiate the reject (or not) at this point in time. A half second later you continue and fly the airplane on the remaining engine(s).
I probably should suggest that you re-read your statement (above) and point out that IF the first sentence is taken as it is written … then the substance of the second sentence amounts only to creating confusion. If, at V1, the pilot initiates the rejected takeoff or he does not initiate the rejected takeoff, as you state … does that not imply that by his deciding to NOT initiate a rejected takeoff, THAT decision is, in itself, the decision to continue the takeoff? There isn’t any need to describe what specific action, not already having been taken, must then BE taken “a half-second” later. That is the whole premise of establishing a V1, a decision, speed. In anticipation of my being criticized for being redundant, the idea of a V1 speed is to provide a point during the takeoff (a “decision speed”) that if something abort-worthy occurs prior to that point a rejected takeoff may be accomplished successfully, and if something abort-worthy occurs after that point – including a loss of thrust (where thrust is the only thing aiding the takeoff) – the lack of initiating a rejected takeoff requires no action other than the continued, previously briefed, takeoff, but with that failure, whatever it is.

Selecting a lower V1 speed, thereby moving that “decision point” further away from the departure end of the runway, must carry an acknowledgement that should an abort-worthy event occur prior to that newly-selected point, a rejected takeoff may certainly be accomplished successfully (just as it would had that point NOT been moved and had the same failure take place prior to reaching that speed). However, it must also be acknowledged, that should that same abort-worthy failure occur just after the newly selected point, after the adjusted V1 call out, the continued takeoff will continue over a longer portion of the runway with that failure than was originally anticipated. That sounds to me like “…measure-with-a-micrometer, mark-with-a-grease-pencil, and-cut-with-an-ax” approach to takeoff calculations. I was always under the impression that following the regulations was what all airlines had agreed, at least in principle, to do, and do on a regular basis. I do not believe that the regulations were written and debated, and eventually agreed, only to have some of them later treated as suggestions that may be disregarded as cavalierly as some here suggest is done regularly. My guess is that IF the concern with this specific designation that is apparently being voiced here was brought to the attention of the appropriate authorities there would be a somewhat detailed decision rendered – I would hope – and after a meaningful discussion and presentation of facts, opinions, objections, and other concerns had taken place, a single, understood, plainly written regulatory requirement would be put into place – and if, or where necessary, alternatives to that requirement and the conditions and limitations to those alternatives would be published alongside. Anything less holds the whole regulatory structure up for ridicule and mockery.

[Junkflyer]

Click the link and go to paragraph 2.3.1.2. It is an FAA publication defining V-1.

[AirRabbit]

Click the link and go to paragraph 2.3.1.2. It is an FAA publication defining V-1.
Yes, Mr. Junkflyer – I am fully aware of what this reference is … and the document to which you are referring is the same document to which I have been referring, the Takeoff Safety Training Aid. And, in reading the paragraph you’ve referenced, it seems to me that is saying just exactly what I’ve been saying all along. You can reject a takeoff at any point prior to V1 and stop safely within the remaining runway. In fact, you can “call” V1 at any point prior to the “actual” V1 speed, and any abort initiated prior to that newly defined point will allow the airplane to be safely stopped in the remaining runway. And I’ve not argued against that fact.

However, if you read the very next section in that same document, you will read the concerns I’ve been describing for not continuing the takeoff after passing what is called “V1.” If you understand the caveats in that next paragraph and you continue to desire to call “V1” at a reduced point … you should be able to see that there now is a confusion regarding how to recognize the point at which the takeoff would be assured even the experiencing a failure - even an engine failure - which has been identified as "V1." But if this definition has now been modified to allow a "reduced V1" the question remains, should we develop a requirement to generate a “second” call-out - where one would be for the “reduced V1” and the second one for the “real V1” - if so, certainly we would have do so without confusing the issue. The first “V1” would be for helping to ensure stopping distance (that is if you choose to stop before you hear “the first V1" (or whatever we determine to call it), you are safe to stop. The “2nd V1" call-out would be for helping to ensure that sufficient performance has been achieved to allow a safe takeoff, even if there were an engine failure AT or AFTER that point. BUT – NOW we have a problem in understanding what to do if an abort-worthy event occurs BETWEEN those two call-outs … go? Or stop? Here’s a suggestion … why not select an airspeed where any abort worthy event occurring prior to that airspeed will ensure sufficient runway to stop AND if that speed is reached prior to any abort-worthy event occurring, we can be assured that sufficient airplane performance has been achieved to allow a safe takeoff – even if the failure was an engine failure. Hmm… wait … don’t we already HAVE that?

[bubbers44]

Yes, we do. It is called V1. Reinventing different V1 speeds because of pilot or company procedures only takes away from what V1 means. Below V1 you abort, above V1 you continue. The one second to react might occupy some pilots minds but after 23,000 hrs never felt it was worth factoring in. I guess the old KISS factor kept me out of making simple things complicated.

[sheppey]

Below V1 you abort, above V1 you continue.

Since decades gone past when I first read research papers on aircraft over-runs caused by a botched abort process, it was clear to me that the chances of an over-run from an engine failure near V1 was much higher in terms of danger than a go decision and take your chances on clipping trees in the initial climb out. There were plenty of over-run accidents in the files but I never saw a tree clipping event due lower screen height.

Since then I had in mind on every take off to keep going in event of engine failure or problem after 15 knots below V1. Tyre failures near V1 have proved to have been the cause of disastrous accidents where the crew aborted instead of continuing. Boeing have addressed these risks to some degree by using 80 knots as a decision speed to stop or go with certain failures. The risk of confusion and hence delayed action increases when the first officer does the take off and an event near V1 causes the captain to resume control and then abort.

15 knots was an arbitrary figure in my mind based upon what I had observed first hand during simulator training. Probably not legal and sure to arouse controversy but I could live with that. The secret was not to tell the first officer and cause potential conflicting views. In any case, few that I knew ever read old accident reports.

[bubbers44]

So the FAA wasted their time verifying a climb profile at V1 that you could do at V1-15. You must have amazing talents to do something that is impossible.

[Yancey Slide]

I read his post as saying he was using V1-15 as the "keep going" speed, not that he'd stop accelerating through V1 to Vr.

[bubbers44]

How much runway does it take with one engine vs two to accelerate from V1-15 to real V1? Balanced field length only works if you use the real V1.

[AirRabbit]

As much as I hate to sound like a broken record … it surely sounds like there are more than just a few who fly airplanes and are VERY FORTUNATE folks to still be here. The point that I think keeps escaping most is that there was a specific reason for having developed the “V-speeds” that are contained in the US regulations – and similar requirements in other nations. I am fully aware of how the numbers work and what they mean – and that humans using those numbers are likely to make some, even if only minor, mistakes … but that doesn’t alter the fact that sometimes it’s only a matter of small, sometimes very small, differences that wind up being THE difference between life and death – or at least accident or no accident. That is the biggest reason I’ve been on my “rant” of examining a lot of the “short cut” procedures that I’ve seen cropping up in daily operations … I call them “cheat sheet” methods to assist in either getting through the training or through a check - that sometimes creep into line operations. MOST of the time, those “cheat sheet” issues are derived from what works in … and then is offered to others to apply to … simulator sessions. Unfortunately, IF those procedures are learned well (and they almost have to be to be used to get through training or checks), there is a good chance that they will find their way into line operations. Two things about that:

1. There is no one around who is a bigger supporter of the use of simulation than yours truly … with the caveat that I regularly offer … that being that I do expect that the simulator should be fully known by the person running the show in that simulator … i.e., either the instructor or the evaluator … and that is because a simulator is NOT an airplane – and the ONLY reason it looks and functions as much like the airplane as it does is because a lot of people have put a lot of effort into making it seem that way. As long as the use of the simulator is kept within the boundaries of what the limitations of the physicality of what that simulator can support … how the programmers have incorporated data generated from an in-flight airplane … how quickly (both independently and dependently) any input made to the simulated airplane (either from the simulated airplane’s controls, i.e., the flight controls, throttles, brakes, etc., or the Instructor’s Control Panel) can be computed, compared to the airplane data, a result generated, and provide an output in the form of a simulator aerodynamic response … the simulator will, indeed, accurately reflect just what the airplane would have done in those limited case applications. However, if you get just outside of those very limited parameters (and believe me, the boundaries of those parameters have been expanded by unbelievable amounts over the last 3 decades!!!) you get into a simulator response that could very easily not be anything like what the airplane would have done. In fact there is an on-going effort – as some of you are aware – titled the “International Committee for Aviation Training in Extended Envelopes” which was specifically chartered to examine what kinds of any additional data or additional data sources would be necessary or possible from which additional simulator programming data could be acquired and used to program simulators to more realistically simulate a given airplane make, model, series, outside of what had been considered the “normal” operating envelope of that particular simulator.

2. Instead of something being developed in a simulator for simulator training or checking purposes, there seems to be those who believe it appropriate, during line operations, to disregard the identified speed above which an abort-worthy event occurring must NOT result in the initiation of an RTO (a Rejected Take Off). Instead, these persons believe that the identified speed does not provide an adequate margin of safety to stop if the RTO is initiated precisely at that speed, and they have decided that they will “reduce” that speed to provide additional runway to enable a safe RTO, should it be required. Once this procedure is decided upon and word is passed between crew members, this procedure is eventually adopted in some simulator training sessions. To no one’s surprise, selection of such a speed that would provide adequate stopping capability in an airplane, also provides adequate stopping capability in the simulator. However, an observant instructor or evaluator can usually pick up on the adjusted “V1” call and question the practice. It doesn’t happen often … but it DOES happen. Then comes the confusion. Additionally, here, in an anonymous forum, there is more freedom to describe such an event without fear of any repercussions (other than verbal). But the fact remains – while such an arbitrary speed reduction does, in fact, provide a greater margin for a successful RTO if initiated at or prior to the “reduced V1 call-out,” in fact, it ALSO leaves an increasingly gaping hole for what might happen if such an abort-worthy failure occurs AFTER that same “reduced V1 call-out.” And that is even more true in the airplane than it could ever be in a simulator.

So … again … overall … I fully understand the motivation that exists for the kinds of things this thread has brought out … BUT … before anyone arbitrarily reduces the speed at which they will “call out” V-ONE, please consider the facts of what that decision may impose on you if another, equally possible failure were to occur – or that same failure were to occur at a slightly later time. The results could be a lot more disastrous … by any measure. If it is your company that has “mandated” your compliance with this “procedure,” I would strongly urge to to bring that question before some arbitration panel or group to discuss the merits and demerits of such a compromise in what the regulatory requirement was intended to provide. If the rule should be changed for one operator … it should be changed for all operators – regardless of what that change entails. If the rule should not be changed – it shouldn’t be allowed to be “adjusted” on an individual basis.

(and by the way -- thanks Bubbers44 - for your cogent input)

[john_tullamarine]

As a sideline view ... one of the main problems relates to the fact that certification stuff is idealised, not real world. The ICAO/regulatory task, progressively, is to reduce the delta.

(a) if the real world circumstances reasonably match the certification, then the outcome in the real world should be reasonably similar to what the (certification) book (AFM) suggests if the action sequence is done per the book.

(b) if not, then expect a variable and, perhaps, significantly variable, delta between the real world results and the certification suggestions.

How do both operator and commander handle this ? No simple answer but a lot of use is made of historical statistics and accident reports to come up with reasonably conservative SOPs for a start.

Winging it on the day is a recipe for disaster sooner or later. Overall the sensible use of historical statistics makes for a more reliable and predictable outcome. That's not to suggest that it will work ALL the time .. but, certainly, it will work MOST of the time.

[AirRabbit]

JT … a very reasonable synopsis of what’s been posted … as usual.

The document that’s been referenced now several times, the Takeoff Training Safety Aid is a 300-page document that does essentially recap most of the original concerns, took into consideration a great deal of the takeoff accidents / incidents (both rejected and continued takeoff) and as we’ve pointed out, that group completely understands the desire to ensure adequate amount of runway remaining in case an RTO is chosen … but they acknowledge that should something else happen (I’ve used the term “abort-worthy failure”) immediately or within seconds of that now-reduced speed call-out, the decision will have become much more complicated to address. Because there was apparently very vocal groups wanting to push for one or another of the individualized approaches, the task of the folks running the effort AND the airplane manufacturers – who were on the “hot-spot” for making the data available and ensuring its accuracy – the result was the “kinda-sorta” two-point description of this “mysteriously defined” speed called “V1” … that says the following:

First, V1 is the maximum speed at which the rejected takeoff maneuver can be initiated and the airplane stopped within the remaining field length under the conditions and procedures defined in the FAR’s. It is the latest point in the takeoff roll where a stop can be initiated.

Second, VI is the earliest point from which an engine out takeoff can be continued and the airplane can attain a height of 35 feet at the end of the runway.

The way I’ve always described the V1 speed importance is to say that the pilot flying has to be ready to abort the takeoff if or when he/she deems it appropriate to do so. Once the power is advanced and stabilized and the brakes are released (normally these things are accomplished simultaneously) there are only two(2) actions that the pilot performing the takeoff can take:

1. reject the takeoff; or
2. continue the takeoff.

The pilot flying may, in his/her own consideration of any possible problem, reject the takeoff at any time UP UNTIL the other pilot says V1, at that point and forward the takeoff is to be continued. In other words, the so-called “decision” is being contemplated from brake release until hearing “V1” – at that point there is NO decision, if the pilot flying had not already initiated the RTO, he/she is now committed to continue the takeoff. That specific speed has been colloquially referred to as “the decision speed,” when it is probably more accurate to colloquially refer to this number as “the no decision speed,” since the decision will have already been made. We shouldn’t have to get wrapped around the axle in trying to determine what that speed actually means. It’s been defined. It’s been described. It’s that we have apparently done a poor job in making line pilots understand the correct meaning of the term.

Perhaps what we should have been saying is ... the pilot flying may decide to reject at any time up until he/she hears “V1” called out, from that point forward the pilot flying is committed to completing the takeoff. If the pilot flying initiates the abort procedure (moves the throttles aft; steps on the brakes; extends the spoilers, or any combination) before he/she hears the other pilot call out “V1” – the airplane should have sufficient runway to safely stop. IF the pilot flying slams the throttles shut and does so simultaneously with the other pilot calling out "V1," we would see the penultimate example of the absolute latest point at which the RTO can be initiated - and it WOULD have been initiated ... in that the throttles were closed - there are no "do-overs" - the airplane is stopping! Observing the penultimate example of the earliest point at which the takeoff is committed, by definition, is not likely to be able to be observed, because there is no observable action that the pilot flying would take to “continue” doing what he/she had been doing from the initiation of the takeoff roll ... the only "observable" action would be to observe the pilot flying taking "no action" as the "V1" callout is made.

[250hrsand counting]

Sorry this is coming late.
i appreciate all the information.
I got the v1 cut the second time i tried it
thanks to you guys on this really wonderful site
I aced the ride:)

[bubbers44]

Great, I loved that airplane.

[I.R.PIRATE]

It was mentioned that Airbus has an automated V1 callout.

Does that occur at V1 or at V1-x?

[john_tullamarine]

Couple of thoughts, where we are looking at new chums transitioning to jets.

I always found it very useful, for such folk in the initial OEI work, to run a couple of failures on the longest sim runway I had available but get the pilot to stay on the runway and just rudder the aircraft down the centreline.

Providing the box fidelity was half sensible for rudder (prior to the FAA's push post the 737 hardover problems this wasn't necessarily the case for -200 sims) this provided a good idea of the relationship between speed and rudder input required to keep on the line after the initial divergence was brought under control.

The second exercise, as competence improved, was to spend some time progressively reducing to a Vmca/Vmcg limiting schedule and CG. The arms and legs exercise required resulted in no further problems with "normal" failure sequences ....

The better manipulators regularly ended up able to handle the worst the box could throw at them for a 0/0 takeoff with a requirement to backtrack the LLZ. The effect on confidence was dramatic.

[Trent 972]

It was mentioned that Airbus has an automated V1 callout.

Does that occur at V1 or at V1-x?

Quote from A380 FCOM
An auto-callout announces when the speed reaches V1.

Without any doubt the auto-callout for V1 is announced slightly before V1 is reached.
I don't know how the call-out is programmed, but 2 knots or thereabouts before V1 seems to be consistent.

[I.R.PIRATE]

Thats what I was trying to figure out, thanks.

Regardless of the numbers in the box, the callout itself and its timing vs the actual bugged V1.

[AirRabbit]

Quote from A380 FCOM
An auto-callout announces when the speed reaches V1.


Without any doubt the auto-callout for V1 is announced slightly before V1 is reached.

Am I the only one who finds these 2 statements to be ... well ... at least non-supportive of one another???

[Chris Scott]

Hi AirRabbit,

As no A380 pilot has answered your question, here's a suggestion. The automated call - "Vee wun" - is likely to be slow and precise. If it commenced at the precise figure of V1, the "wun" would not be heard until after V1, potentially leading to a late abort. It may be that the SOP is to treat the "wun" as defining the decision point.

Perhaps the above will provoke a properly informed response!

[Centaurus]

The V1 call in simulator training general, is normally made by the PM. From personal observation the vast majority are called slightly late and I have never observed an early call. By slightly late, I mean one second or more after the ASI has gone through V1 and I am not talking about the deliberate V1 minus 5 call under discussion.

It should be remembered calls by the PM for (say) 80 knots or 100 knots or V1 or VR, during the take off run are purely support calls or back-up calls. They are not supposed to be action calls. If for some reason the PM fails to make any one of these calls, it shouldn't matter to the decision making of the captain who has his own ASI.

The captain and first officer each have an ASI. Depending on the design, there may be moveable "bugs" set at V1 and VR as well as other speeds. Assuming the company procedure is the captain is handling pilot for all rejected take off procedures, then he should be well aware of V1 and that is by observing his own ASI. The PM support call is handy as a reminder and that is all.

Again from numerous observations in simulators during type rating training where the PM who makes the support calls is quietly told by the instructor, to "forget" to call VR, we have seen some alarmingly hesitant delays by the PF who then fails to rotate at the correct VR because he momentarily disbelieves his own ASI simply because of no call by the PM.

In other words he was waiting until being told by the PM to rotate The worst I saw was the PF staying on the runway 37 knots after the bugged VR because he was waiting for the PM to call "Rotate". As we went into the overrun and through the localiser aerials, the PF looked across the cockpit at the PM and said accusingly "You forgot to call `Rotate`" :ugh:

A smart pilot will always have an eye on the ground speed reading nearing VR and knows what its approximate indication should be approaching the airspeed check at 80 knots (737) and especially nearing VR. The PM support calls during the take off roll will always be with us but as said earlier, they are back up only - not necessarily action calls.

[underfire]

Centaurus, JT, all

Interesting comments to say the least. The cert numbers should never even shown anywhere. I feel they have little basis or foundation in reality, and just serve to confuse the issue. When was the last time your MLW 737-800 was on final at a sea level airport, ISA temp, flaps 40, at 140kts at the FAF?

In designing RNP procedures, specifically the missed and EO missed, a flight validation is required of the procedure. After seeing a few of these, it is something that every pilot should go thru, and at multiple locations. Flight val uses the assumption that putting one engine on idle, is the same as EO.
These procedures are coded, so the aircraft has everything it needs to know about the real-time conditions. Now see the momentary descent calcs, and actual climb rates.

The movement to MDA is certainly justified, but unfortunately, it was not followed thru on what the decision altitude should be, but simply leaves it up to the operator to decide when to initiate GA, and not bust the MDA.
The assumption of 50 foot momentary descent is a joke, for any aircraft, and even 100 foot is virtually impossible if one is EO.

[AirRabbit]

In an attempt to credit those here who have been discussing (even though it may have sounded argumentative) whether or not V1 is really a “decision” speed – or more toward the discussion (argument) – whether or not it is the speed at which a “decision” is made as to whether or not an abort should be initiated. Clearly, THAT specific airspeed is described, at least by the regulator (in the US anyway – and by implication, elsewhere, if we’re discussing a US-built aircraft flown under another country’s regulations), as being a speed that has to be viewed through two (2) perspectives:
1) the first perspective is the perspective of an ‘engine failure’ speed (called VEF) where the speed under discussion (argument) MAY NOT be less than this ‘engine failure’ speed AND it cannot be less than the minimum ground control speed (VMCG) … and it is selected by the person(s) applying for the certification; and
2) the second perspective is a bit more practical in that it must be chosen on the basis of not being less than the ‘engine failure’ speed (described above) but it must include any speed that is gained with the critical engine failed, during the time interval between the instant at which the engine is failed and the instant at which the pilot, having recognized the failure, takes the first action to reject the takeoff – and that recognition is defined by the pilot applying brakes, reducing thrust, deploying speed brakes, etc.

So, in the strict understanding of the “noun-verb-object-subject” kind of thinking, V1 is the speed at which a decision, having been made previously, is expressed by outward, recognizable, action. Of course, if the “decision” that is made is to CONTINUE the takeoff, there would be no outward, recognizable, action taken by the pilot, in that he/she would simply continue what he/she had been doing up to that point.

Now, I’ve known some folks who, having been born and bread in the US “southern” states (where, historically anyway, it does often take longer to say virtually anything) do, in fact speak more slowly. Some describe it as ‘deliberately.’ Unfortunately, and incorrectly, sometimes this characteristic has been rumored to be due to an absence of intelligence or proficiency in the spoken language … however, having lived in the US “south” for most of my life personally, I KNOW that any slowness of speech is due directly to the physical exertion required – and, being in the south, where the ambient temperatures get to those typical of a “southern climate,” virtually no one desires to work muscles at a rate that would tend to generate more internal body heat … and that includes a deliberate choice to speak more slowly than do our “northern” neighbors. At least, that’s my story … and I’m stickin’ to it, ya’ll! ;)

But, be that as it may, the time it takes to say “V-1”, out loud, even if you’re a “southerner,” doesn’t take anywhere near as long as some believe it does. I’m NOT saying that if you or your airline desires to call V1 at a lesser speed … that an accident surely cannot be avoided. All I’m saying is that individually choosing some arbitrary point below which some things are more likely NOT to happen … and above which other things are more likely TO happen … is a pretty poor way to approach the understanding of the aerodynamics under which the airplane you’re piloting was certificated.

The bottom line I think is this:
TRUE enough … these “chart speeds” are speeds generated during the certification process. But they translate, and do so directly, into day-to-day operations of your airplane. A knot or two here or there … a second or two there or here … are not likely to cause or prevent any specific result. Tires wear … contaminants build up on runways … brakes wear and get hot and “out-of-round” … runways have hills and valleys … temperatures on the runway are different than what is “reported” by the tower … wings get dented ... and list goes on and on and on. But at some point, there has to be some specific parameters that simply have to be chosen and we owe it to ourselves and to the profession to follow those parameters. What is the purpose of having that information if it is thought to be irrelevant or immaterial? If we’re going to be professional and do what we’re supposed to do … I think we have to make the best of what we’ve been taught, what we are given, and put it all together in the proper way, at the proper time, and do it all professionally. Anything else is simply NOT professional. We each have a choice to make … and I’ve made mine.

[JammedStab]

First, V1 is the maximum speed at which the rejected takeoff maneuver can be initiated and the airplane stopped within the remaining field length under the conditions and procedures defined in the FAR’s. It is the latest point in the takeoff roll where a stop can be initiated.



For an engine failure scenario, only if at field limited weight and no remaining reverse is used(on a dry runway, wouldn't you say.

[Trent 972]

AirRabbit, The V1 auto-callout on the A380 takes about half a second and the V1 speed is reached at the end of the auto callout.
Seems perfectly reasonable to me.

[AirRabbit]

It sounds that way to me also ... thanks!

[misd-agin]

I'd love to see a heavy weight takeoff, runway limited weight and climb limited weight, where the decision to continue was made at V1-15.


I think it would be quickly obvious that it's a dumb, and completely unsupported, technique.

[AirRabbit]

...and if, after that call (implying the decision having been made to continue) there were an engine failure to occur at, say V1-12, you would indeed see that such a decision at that point was just as you described!