747 V1 Cut Advice

[RandomPerson8008]

Hi,

This is a bit embarrassing, but I am in the process of being trained on the 747-400 and find myself struggling a bit on V1 cuts.

Does anyone have any tips on how to handle the airplane, or more specifically the simulator, during this maneuver? It is my company's practice to always do the V1 cuts at 500 feet RVR with a 15 knot direct crosswind and 300,000 kilograms gross weight. It's always the upwind engine that will be failed in a "seizing" manner (not a gradual spooldown), so at least it's predictable.

I find that the trouble comes not in maintaining runway centerline immediately after the engine failure, but in that period of time immediately after rotation during which you can no longer see the runway, yet are still on the ground. Obviously an immediate transition to instruments is necessary upon rotation. However, I too often find myself in an uncoordinated condition and not tracking runway centerline properly after rotation. With that said, my V1 cuts are survivable, just not up to standard. I have attempted about 6 so far and only 2 have been done well.

Perhaps I need to rotate the airplane more quickly. The plane almost seems to need a "double flare" due to decreasing pitch response once 5-7 degrees is reached. This can lead to extended time in the aforementioned zone where the runway is not visible, yet the airplane is still on the ground.

I am transitioning from a small jet airplane with fuselage mounted engines. Needless to say, the difference in engine out handling is quite drastic.

I look forward to the responses.

[Junkflyer]

Hold it on the runway a touch longer so your rudder input is just right before you rotate.

[noip]

The general technique I used on the 400 - the points are a little overlapping, but you get the drift. All people can do is talk about how they handle the situation, and for you to read and try and get something from it.

Normal caveats apply.

• Keep the aircraft straight with rudder initially, then lock your rudder as you reach rotate and use aileron to keep the wings level until you are safely flying away.
• At "rotate" .. THINK ... pause, and then play the rotation rate to allow the airspeed increase to stop at V2 - typical attitude for reduced thrust would be about 13 deg from memory. We were always instructed on specific rotation rates, however that is not much good if you get to the attitude with the wrong speed.
• Once you are safely flying away with the gear retracted, correct rudder to allow level yoke with wings level. Think of it as "push rudder to lift the low side of the yoke".
• TRIM Rudder
• Engage Autopilot

Three issues:

• Is more thrust available?
• Rotating mechanically to the nominated attitude will have you airborne below V2 (been there, done that)
• Remember to raise the gear (embarrassing if you don't)

Hope some of this helps.


N

PS .. yes, as you approach 10 deg, the pitch response becomes less - an increase in backpressure is required, BUT the speed is the thing. You need V2.

[wiggy]

Keep the aircraft straight with rudder initially, then lock your rudder

noip's absolutely right.

Push required rudder in, then lock it.

Pitch when/as required. Do not rush the rotation, you'll need a slightly firmer pull at top end of the rotation but if you nail the engine out target pitch attitude using the right rotation rate you'll find V2 will take care of itself.

When clear of the ground use the yoke to control heading.

Obvious point: Make sure you've got the raw heading as well as the pitch in your scan by frequently scanning down to the PFD compass arc... the Flight Director can be very misleading at this stage.

Don't rush to "unlock" the rudders when airborne, if your inputs are roughly right she'll fly OK, so don't correct any crossed controls until the gear is selected up.

[heavydane]

The above is good advise.

More rudder is a good ting!
Do not rush the rotation, spend the extra time on the runway to ensure directional control.
Do not rotate above 10 deg. before You are well of the ground(tail strike)
Do not chase the speed, V2+10 is good too.


Regards
Heavydane

[sodapop]

Some, hopefully, useful tips;

Apply nose down pressure if you start drifting away from centerline to give yourself better nosewheel response

Rotate slightly slower than normal and lock the rudder with the heel of your foot

Rotate to 11 degrees which you can recognize by placing the square aircraft symbol directly over the 10-degree line on the ADI (call it "Top Hat"). Check speed at V2.

"Gear Up", center the yoke using aileron and then squeeze a little rudder.

Final rudder adjustment as required at 400' (THR REF VNAV SPEED)

Have fun.

Soda

[TheChitterneFlyer]

Perhaps I need to rotate the airplane more quickly.

The rotation rate should be less than the normal four-engine rate which will then allow the airspeed to increase towards V2. Do remember, however, that when you have "positive climb" and you then select the gear UP there will be a temporary increase in drag as the gear-doors open. This will require a small adjustment in pitch so as not to allow the airspeed to reduce; with practice, you'll anticipate these small variations in pitch as you become more accustomed to the aeroplane.

If you're operating with reduced thrust, it shouldn't be neccessary to increase the thrust towards maximum... unless, of course, it's all going wrong!

Hold it on the runway a touch longer so your rudder input is just right before you rotate.

When operating at the higher end of the weight schedule this might not be an option (high ambient temperature & pressure altitude/limiting runway)... is there enough tarmac/concrete in front of you?

Chin, chin

TCF

[an3_bolt]

500' vis - 150m low vis.....seen more than a few guys rotate and roll over on that one!!

I'm no expert - some around here have been doing this one for over 20 years - but a little if it helps.

Track what you can see of the runway centreline and lock it in........do not cycle the rudder. The problem of not being able to see towards the end of runway can lead to some viscous cycling - muscle memory and lock it. A good PNF will assist you in the low vis with current tracking or deviation etc or even the LLZ up can help....

I find a "little" forward pressure on the elevator helps with the rudder control, especially during stronger crosswinds. Dont forget a little aileron to keep wings level.

When rotate - rotate on the PFD and hold the rudder - do not release the pressure. Hold it. Aileron to hold wings level.

PFD pitch bars are at 2.5 degree intervals.....I'm a bit of a monkey so I use the Gorilla rotate ...... I say to myself as I rotate ..."1 banana (2.5 degrees), 2 bananas (5 degrees), 3 bananas (7.5 degrees)....4 %^$bananas(10degrees with extra backpressure)...but most importantly the correct rate will have you at V2 flying away with the gear down.

Wings level with aileron - rudder locked.

Retracting gear - if you hold attitude current attitude to maintain V2 - when you select gear up - the gear doors open, extra drag and below V2 you go on the IAS....then the inevitable fight to get speed under control. Plan ahead. As you select gear up, nose down 1/2 degree and as you reach towards the end of the gear retraction cycle - raise the nose 1.5 degrees to maintain V2.

As Noip says - lift the downside of the aileron control wheel with rudder OR alternatively "squeeze" the skid indictor on the PFD back to the neutral position.

When under control - bring the track box on the ND into the scan or the track pointer on the bottom of the PFD and continue on your merry way cursing
a - the overhaul facility for a &^&($#& crap engine
b - cost cutting
c - bad coffee
etc etc

Smile and wave boys - nothing to see here - move along!

Really nasty is an engine surging on a 767 during rotate......

[B4MJ]

A little more forward pressure on the yoke should solve your coordination problem on liftoff. There is precious little excess friction on the nose wheel to start with when the power is balanced and the sudden seizure of an outboard overtaxes the nose wheels ability to resist the sudden turning moment. Pushing firmly puts more weight on the nose gear and helps to nail the nose straight. Don't think about returning to centerline, just parallel it. If you're having an exceptionally good day, think about rolling a little extra aileron opposite your hard leg just as the nose gets light. This will counteract the loss of nose wheel friction and you'll lift off with almost level wings. But don't even think about this little "extra" until you've got the rotation down pat.

Don't rotate any faster. Your Boeing manual calls for approximately 2 1/2 degrees per second rotation starting at Vr to 15 degrees pitch up with all engines and approximately 2 degrees/sec rotation to 12-13 degrees with an engine out. You may have trouble determining what 2 degrees/sec is but you do know how to count. So, if you count to six while you're rotating, and the nose ends up at 12 degrees pitch up, then you've managed the 2 degree/sec rotation. Same thing applies if all engines are working. 15 degrees pitch up attitude divided by six equals 2 1/2 degrees/sec rotation which is exactly what the manual recommends.

6 seconds is the approximate rotation time for ALL takeoffs whether there is an engine failure or not. So, the book procedure amounts to a smooth, continuous rotation that takes about 6 seconds duration starting at Vr with or without an engine failure. 15 degrees pitch/all engines, 12 degrees/3 engines. But the same 6 seconds to reach that pitch.

After the six seconds and you're airborne, now it's time to return to the Flight Director pitch bar that you so carefully ignored or "looked through" during your rotation and it should be spot on. If not, then small corrections should be all that's needed to make it spot on.

The reason to "look through" the pitch bar is that it's sluggish and will only be at about 10 degrees shortly after lift off (It sits at 8 degrees on the ground and takes longer to get up to 15 degrees than your 6 second rotation does). If you make the mistake of stopping your rotation when the nose first reaches the pitch bar then the airplane will over accelerate and then the FD will command too high a pitch to get you back on speed. Avoid all that "chasing the pitch bar" by ignoring the pitch bar until you've REACHED your desired pitch attitude.

[BOAC]

RP8 - get a training Captain to explain to you why the pitch rate slows during rotation - it is pretty 'normal' with low mounted tailplanes - I guess your 'past' had 'T-tails'?

You have not specified the V1/VR gap (and I assume also you mean 500mRVR?). Like The Chitterne I think 'delaying' rotate is fraught with danger, not just runway remaining but obstacle clearance - think of where you are placed perf-wise if second engine goes due to debris damage? Will you make the screen height? I would run that idea past your trainers if I were you!

[763 jock]

If you are on a transition course, ask your instructor for a wet V1. Something like a 20 knot split between V1 and VR will give you plenty of time to practice controlling the swing on the runway. When VR is reached, a slightly slower rotation rate is required.

You can then increase the V1 as your technique improves. I've used this method when training pilots who are having trouble. Works a treat.

[catpinsan]

rudder effectiveness

As the airplane accelerates the rudder effectiveness increases. Assuming you have the technique mastered while rolling for take off (visual ref and the nose moving away from RW HDG), here's what you do during the transition to airborne:

Either,

you can 'lock' the rudder as described in many of the posts - in this case you will have to give quick, positive (mind me, not violent) aileron input as you get airborne, to counter the increased rudder effectiveness and keep wings level i.e. the wing will tend to go down and the airplane bank in the same direction as the rudder was given.. After getting airborne and having the situation under control to your satifaction you will have to settle down with enough rudder (and finally trim it correctly) to keep the control wheel centred. You will find that the airplane may fly with a minimal/slight bank into the live engine. Subsequently the usual rudder/trim changes will be required depending largely on the configuration and speed/thrust etc.

or,

you can ease off ever so slightly on the rudder as you get positively airborne - how much? This, you would have to play by what your instruments tell you.
A KEY INDICATOR IS THE SLIP/SKID INDICATOR (below the sky pionter), equivalent to the 'ball' of yore. Airbus called it a trapezoid, last I flew one. If this is not close to centred it will require a lot of effort to fly wings level and you will not find a steady state. Boeing recommends that it be slightly off centre towards the live engine and this works like a charm. Whichever side the slip/skid indicator is displaced, that's the side that needs more rudder.

Remember you will be transitioning from a highly 'cross-controlled' situation on the ground to one less so in the air. Whereas the airplane cannot bank significantly with wheels on ground, ther's nothing to restrict it once in the air. With an engine out cross control is the natural state, but it can be minimised by having the correct amount of rudder (and trimmed out).

In fact it can be likened to lifting off in a cross-wind. As an aside - On the 744 i have found some sort of change of rudder control speed regime around 120KIAS. At this point, in a x-wind take off the airplane instead of weathercocking into the wind tends to have the nose go away from the wind with the steady rudder input which was being used till this point.

A good scan (include slip/skid, and bank pointer and target pitch attitude) and quick authoritative inputs to aileron and rudder are the key. As you get airborne keep wings level, get the slip/skid 'centred' if it isn't and get the nose upto around 11 to 12 degrees. and once steady and stabilised, then follow the FD pitch commands. On a heavy 744, there are occasions we have to go by pitch attitude and disregard the FD as we may not perceive/fly the small changes that the FD might be making. I'm assuming this is due to the huge inertia involved. Always have the raw data under control.

[RandomPerson8008]

Thank you very much for all the replies. They have been very helpful. I look forward to employing these strategies when I get into the sim again.

Originally Posted by BOAC

I guess your 'past' had 'T-tails'?

You have not specified the V1/VR gap (and I assume also you mean 500mRVR?).

Yes sir, I'm coming from a T-tail small jet with fuselage mounted engines.

The V1/VR gap we are using varies but it is typically about 15 knots.

We are doing everything in 500 ft RVR (150m).

[BOAC]

We are doing everything in 500 ft RVR (150m).

- gulp! I am quite surprised that no-one has actually discussed rotation technique in a 'traditional aircraft! It should be around lesson 1. I would have hoped that 15kts would be enough to peg the yaw?

[warmkiter]

Engine failure after GO

Hi guys, here is a little tip how to stabilize the initial recovery on B744

What you need is the right amount of pitch and rudder. But that's nothing new.

Try this and you will be able to let the yoke go and have a trimmed A/C BEFORE you punch in the AP

You will need back trim. loosing an engine will cause your nose to drop. The B744 needs in sim 3 seconds of back trim. Use your thumb, count till 3 and you can nail those 10-12 pitch depending on weight. easy

now comes the tougher part. Rudder. If you loose Nr 1 or Nr 4 engine with full thrust, your amount of rudder required will be close to full travel. Don't kick it in, just apply smooth. With D-TO 60 it's about half travel. The rest is in-between. So you know before T/O pretty close how much you have to use that rudder. What the B744 doesn't like at all is alternating rudder-imputs.that makes the A/C go really shaky and all parameters go crazy. Apply your expected rudder-imput and check the coordination-indicator. After that correct only once!!!Nail your heels on the ground after that. Hope you hit the right one;-) little trim for neutralizing rudder-pressure, just relax and enjoy the ride. With some practise you will have it stabilized in 200' and just relax and wait until you got the 400' to start the procedure.

L

[RandomPerson8008]

The sim went much better today...we did one cut and it was within standards. Thanks again for the advice, it must've helped.

The only criticism I got was on my rotation.....I was roughly on the 2 degree per second target overall. However, when the instructor showed me a graph of pitch vs. time during the maneuver....I was at 7 degrees within 3 seconds, then I backed off down to 5 degrees, then pulled it back up to 10 degrees, then back down to 8, then finally up to 12 degrees.....so there was some oscillation going on rather than one smooth rotation. Tail clearance was roughly 1.8 meters at its lowest point.

The rotation is vastly different on this plane than my previous....my old bird required a "counter rotation" after the initial backforce to prevent over-rotating...the boeing is precisely the opposite and will take some getting used to.

Hopefully I can maintain this success, thanks again.

[B4MJ]

Good news! The smooth rotation will come with time. Old habits are hard to break and as BOAC says, rotation technique is usually covered in depth on period one. A few more V1 cuts should smooth it out perfectly.

Your Flight Crew Training Manual shows a Typical Rotation - One Engine Inoperative pitch attitude of 10.6 degrees at the 5 second point after Vr. At 10.6 degrees you have a minimum tail clearance of 86 cm. Tail Strike Pitch attitude is only 12.5 degrees.

So your instructor wants to make sure you don't over rotate another 1.4 degrees into the tail strike zone while you're still on the ground. And obviously you didn't as your minimum tail clearance was 1.8 meters.

You'll going to love the 747-400. Without getting into an A vs. B argument, it's simply one of the best flying jetliners ever built. (with all due respect to the L1011).

[crbnftprnt]

At least in our sim, what works is to immediately (but smoothly) put in full rudder. You will immediately be reducing that input a bit; but you will more quickly establish centerline tracking that way than if you didn't put enough in in the first place.

[b737NGyyc]

Great advice from all. Here is my input albeit from the baby of the Boeing family (B737NG). From the discussion above the techniques are very similar regardless of size.

This simple rhyme is what I would teach my trainees for V1 Cuts.

Squeeze (rudder to maintain centreline)
Freeze (rudder input)
12 degrees (target pitch attitude)

Squeeze the rudder in unison with the thrust decay, obviously a seizure or severe damage will require rudder to be inputted faster than the thrust decay from a flameout.

Freeze the rudder input required to track centre line and lock your leg by placing your heel on the floor. Do NOT change this input at rotation use aileron to keep the wings level.

Maintain the target pitch attitude and the airspeed will settle nicely in the V2 to V2+10 range and minor pitch changes will set the speed right at V2. Where I have seen more pilots get into trouble is over rotation and chasing V2 with aggressive pitch changes.

Some aileron is required at rotation to maintain wings level. Hold these inputs until a positive rate of climb is achieved and the gear is retracted then reduce the cross controlled condition smoothly by inputting rudder as required to level the yoke.

Good luck in the sim she can be an unforgiving mistress.

[sevenstrokeroll]

dare I say it? I think the secret is to trim the rudder while still on the ground...at least a bit of it.

how can someone ''muscle lock'' the rudder, when the rudder trim could just be moved to the approx position for outer engine out?V1, lose the engine, rudder to track centerline and move the rudder trim..., Vr, smoothly rotate on instruments, positive rate gear up. if you are moving the YOKE, your thumbs are pointing to the rudder pedal you should step on a bit more.



we all know the sim is the sim...the plane the plane

do you have the engine volume on?


(edit to clarify sequence of VEEE ONE call and then engine failure...)