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Olendirk
29th Jun 2007, 17:51
Hi fellows,


heard about that fact and couldnt believe it. Guys pushing the wrong rudder after enginefailures. Somebody made experience with that? Well, I see that people can have bad days, especially in simulator when they are nervous. How can that be prevented? And why does that happen?

Byebye


OD

A Very Civil Pilot
29th Jun 2007, 17:58
If you've been practicing it in your mind for a while, thinking that no 1 will go, when it comes to the sim you might well push the right rudder regardless of which engine has gone. 50/50 chance you'll be right.

hetfield
29th Jun 2007, 17:59
Well, once I got almost killed by that, during a training mission. The other one was in a sim. In both cases the guy assumed an engine failure. Maybe assumption was to the wrong side....

Zeffy
29th Jun 2007, 21:24
...Guys pushing the wrong rudder after enginefailures. Somebody made experience with that?

(More that twenty years ago) a DC-9 was lost (http://amelia.db.erau.edu/reports/ntsb/aar/AAR87-01.pdf) at KMKE; causal factors included jumping on the wrong pedal.

.

NSEU
30th Jun 2007, 02:04
Does "step on the ball" apply to all aircraft? i.e. If the slip indicator goes left, you push on the left rudder pedal.

And how hard is the slip indicator to see (e.g. in a glass cockpit) when one engine is badly stalling?

Regards.
NSEU

parabellum
30th Jun 2007, 05:08
Happens in the SIM fairly regularly, more with twins than threes and fours. When there is a reasonable gap between V1 and Vr and the failure is given just after V1 then usually no problem but if V1 and Vr are close together and the failure is given after rotate into a dark night sky then, unfortunately, the SIM seldom replicates the yaw in a realistic fashion and this can cause confusion resulting in the wrong pedal being pushed.

BEagle
30th Jun 2007, 08:24
To make a bicycle turn right, the left side of the handlebars is moved forwards.

To make an aeroplane yaw right, the right pedal is pushed fowards.

Sometimes confuses newcomers.......

But 'step on the ball' always works!

Scallywag
30th Jun 2007, 08:56
Dead leg, dead engine always worked for me in twins.

Broadcast Control
30th Jun 2007, 08:57
I suspect that one reason for such errors is that pilots instinctively bring with them habits from years of driving cars. When you want something to stop you press the brake pedal with your right foot.
It would be interesting to know if experienced simulator instructors have noticed if errors made could support this theory.
It is quite common to see people who have been riding motorcycles occasionally operating the throttle the wrong way when they start flying.

Monarch Man
30th Jun 2007, 14:00
The secondary effect of yaw is roll, so if you can't get the stepping on the ball thing right, stop the roll with the rudder, it works every time.

A37575
30th Jun 2007, 14:19
Have not yet struck wrong rudder input in the 737 simulator following engine failure. However several nasty frights training in both military and civilian twins.
When simulating engine failure in the HS 748 I pulled back the throttle sharply shortly after gear selected up (in retrospect silly thing to do but I was young and overconfident). The pilot under training was experienced and the take off was under the hood. Unfortunately he applied wrong rudder before I could prevent it. Aircraft rolled sharply and fortunately I was able to re-introduce power as well as get aircraft under semblance of control.

Same problem when closing throttle on Dakota (military DC3). Instrument take off and pulled the throttle too early for safety. Got away with it due good fortune.

Single engine (zero thrust set on "dead" engine thank goodness) low level go around (again on instruments) during instrument rating instruction using a Duchess. Student pushed up the live engine throttle very fast and at same time he anticipated the expected yaw/roll - except he pushed on wrong rudder. Alarming yaw and roll and although I was on alert for wrong rudder input the student caught me this time. Again got away with it. My fault for allowing the student to get too low to the ground before initiating the single engine go-around. Zero thrust on "dead" engine meant power was available for recovery to wings level. Practice feathered landings and go-arounds are too risky if mis-handling occurs by student or the instructor.

Worst case also in Dakota. Instrument take off from brakes release. In retrospect unlikely scenario but that's how it was in the old days. The student (My Commanding Officer) lifted off and seconds after gear lever selected up he called "engine failure starboard side."

He had lots of rudder and aileron applied and was obviously struggling because aircraft was banking sharp right. He attempted to reach up and hit the starboard feathering button. Luckliy I was able to prevent his fingers from touching the button because both engines were delivering take off power so obviously no engine failure. On taking over control it was clear we needed almost full aileron and lots of rudder to prevent yaw /roll to the right.

I looked outside at the starboard wing and saw that the rubber de-icer boot that runs the full length of the wing, had split asunder and was flapping over the leading edge and playing havoc with wing lift. Hence the roll/yaw moment. Circuit carried out with three quarters wheel needed to counteract loss of lift on contaminated wing. Flapless approach and landing carried out with wing steadily dropping during hold off. I was concerned about effect of flaps with contaminated wing which is why I decided to go for a flapless. Touched down with last of full aileron control applied. Later inspection revealed rubber de-icing boot had perished probably due tropical conditions over several months.

old,not bold
30th Jun 2007, 15:48
Dead leg, dead engine always worked for me in twins

That's funny, I was drilled into "Live Foot Live Engine" which worked when called upon to do so, the only problem being remembering what to do after that.

Is this the same as seeing a glass as half-full or half-empty, a matter of temperament?

Zeffy
30th Jun 2007, 15:53
Dead leg, dead engine always worked for me in twins.

When I was instructing, the trainee was required to remove the dead foot from the rudder pedal and gently stomp on the cockpit floor as part of the confirmation process.

(FWIW...)

ITCZ
30th Jun 2007, 15:57
Dead leg, dead engine
Live leg, live engine

Those are all secondary things to make sure you don't 'do a Midlands' and shut down the wrong donk.

If you are scanning your flight instruments and you have a particular heading or track that you would like to fly etc, :hmm: well, they will tell you which control inputs to make BEFORE you look at secondary guages like N1/EPR/N2/FF or RPM/MP/Torque!

Little rhymes like the above are for secondary actions, after establishing/maintaining control.

hoggsnortrupert
30th Jun 2007, 21:42
Left "Right"
Right "Left"
I was Taught "Right" in the begining on my first multi , DEAD FOOT DEAD ENGINE, "take the foot off the rudder pedal" he would Bellow!
Trim it out, keep your dead foot on the floor, If needed use it and return it to the floor.
Twins not a problem,(Trikes) included.
At times if power is low and one fails, a hand full of power lever helps in the identity, this should be the same in a Quad, "not that I would know".
As for the SIM, I was taught, Look ahead (which you should be) and as the nose starts to DEVIATE from the Center line, hold the Center line with the wudder! apply "Wudder" at the rate at which the nose is deviating, and lift my foot off the inactive pedal?
Yep, still see others that do it or understand it different.
I am never ever amazed at anything any longer.
Just more cynical!


H/Snort:ugh::ugh:

hoggsnortrupert
30th Jun 2007, 21:44
In last post, Lift it off when you don't need it, ie airborne and trimmed out.

H/Snort

rodthesod
30th Jun 2007, 22:55
BEagle, with all due respect -

To make a bicycle turn right, the left side of the handlebars is moved forwards.

A bit off thread perhaps but I suggest that, if you try to steer a bicycle like that, you wear a crash helmet - you will almost certainly be surprised even if you don't fall off. Remember your gyroscope rules of precession and think again.

Back on thread, 'Step on the Ball' or 'Dead Leg - Dead Engine' always worked for me.

rts

BizJetJock
1st Jul 2007, 05:46
Several of the above posts demonstrate the misunderstanding that causes this problem. All the "Dead leg/Live leg/Stamp on floor" stuff is for after you have the aircraft nicely under control using the correct rudder.
The main problem is that the majority of modern pilots very rarely need to use the rudder at all, and when they do it's often engine failures in the sim which as parabellum says is not very good at yaw cues. Stepping on the ball is a good introductory way of teaching the use of rudder, but not nearly as good as recognising yaw directly and preventing it rather than curing it. A few hours on a taildragger would soon teach people all about this!
Interestingly, if you read the details on the Concorde accident one of the factors raised (which had no bearing on the outcome) was the poor response of the PF to the yaw following the engine flameout (caused by the fire effects from the fuel tank leak). They attributed this to the fact that the sim did not accurately model the aircraft behaviour in yaw, and base training in the a/c was limited to single engine failures with a slow spool down; therefore the PF had no experience of how the aircraft behaved with sudden engine failures. Whether more general experience in controlling yaw would have helped is not explored.

ITCZ
1st Jul 2007, 09:29
Several of the above posts demonstrate the misunderstanding that causes this problem. All the "Dead leg/Live leg/Stamp on floor" stuff is for after you have the aircraft nicely under control using the correct rudder.
Exactly.


I don't understand this problem of "recognising yaw" that has been discussed. Twin piston, twin turboprop, and twin and four engine turbojet, sim and aircraft, the yaw at low speed/high thrust is immediate and easily detectable with reference to heading information etc from primary flight instruments.

Australian regs allow up to initial 20 degree swing off required heading and subsequent 5 degree heading/tracking tolerance for EFATO. Even a cruddy 30yo BAe146 sim with a 286 microprocessor running the show could model that sufficiently well. I should say -- if you could fly it in the sim, you could fly it on the line!

Is there a problem in other types?

I wonder if the problem is not more to do with expectancy, and/or a scripted approach to dealing with proficiency checks?

Eg: one of our ports used in sim exercises has an immediate left turn through 120 degrees at 400' AGL or departure end of the runway. A lot of fellows imagined that they would get a failure of No 4 - outer engine on the outside of the turn. That would be the "hardest", obviously the checkie would set that up, for sure :E Fun and games ensue when the checkie fails No 1.:eek:

Olendirk
1st Jul 2007, 13:30
Well, in my young career it works great to watch the engine instruments. failures are easy detectable as mentioned above. then just push the right rudder to keep the airplane aligned with the runway. After v2 is also fine with the engine instruments. you can just wings level and then push the rudder to the aileron down side.

right?

what are your training and flying tips?

balsa model
1st Jul 2007, 14:57
BEagle said:
To make a bicycle turn right, the left side of the handlebars is moved forwards.
rodthesod said:
A bit off thread perhaps but I suggest that, if you try to steer a bicycle like that, you wear a crash helmet - you will almost certainly be surprised even if you don't fall off. Remember your gyroscope rules of precession and think again.
Actually, wouldn't the gyroscopic procession be helping Beagle?
The concern should be with the centrifugal force. After the push, the procession forces acting on the front wheel will cause the bike to roll to the right. In this attitude, part of the weight will counteract the centrifugal force of his right turn.
Please, wear helmet anyways.
BM

rodthesod
1st Jul 2007, 17:48
BM

Actually you're completely wrong about gyroscopic prEcession. Apply an external force to a gyro (spinning bicycle wheel for example) and the effect of precession is to move the gyro as if the force had been applied at a point 90 degrees removed in the direction of rotation. So pushing the left handlebar forwards will result in bank to the left - not exactly what is required for a turn to the right.

As any cyclist / motorcyclist knows you don't move the bars to steer, you shift your c of g L or R - gyros and castor angle do the rest. However if you require an emergency fast turn to the right you initiate it by pulling the left bar towards you - it's VERY effective.

rts