#10 Engine Failure During an Overshoot
To determine your ability to maintain safe control of the aircraft following a simulated engine failure during an overshoot and carry out the appropriate emergency actions.
You will be asked to establish the aircraft in a final approach descent to a simulated landing in a landing configuration at the recommended final approach speed. Once the approach is stabilized, the examiner will call for an overshoot and simulate failure of an engine as you increases the power during the overshoot.
Using control application in the proper sequence, you must control the aircaft, perform the vital actions and establish a positive rate of climb, if the aircraft is capable, to achieve a safe go-around. The examiner will establish zero-thrust on the simulated inoperative engine after you have simulated feathering the propeller.
With respect to aircraft control, your ability will be assessed based on the following criteria:
- recognize the simulated engine failure promptly;
- control the aircraft;
- set the power controls and reduce drag by using control application, in the proper sequence;
- identify and verify the inoperative engine;
- bank toward the operating engine, as recommended for best performance;
- maintain directional control within ±20 degrees of assigned heading.
- establish a positive rate of climb, if the aeroplane is capable;
- accelerate to and maintain one engine inoperative best angle-of-climb speed (Vxse) (+10/-5 knots), if required for obstacle clearance, or accelerate to and maintain one engine inoperative best rate-of-climb speed (Vyse) (+10/-5 knots);
- trim the aircraft, as required; and
- continue the overshoot towards a specified altitude;
With respect to cockpit management, your ability is assessed using the following:
- locate the necessary controls and switches to carry out and complete the emergency procedures in accordance with the approved emergency procedures checklist (Engine Failure during Takeoff or Overshoot):
- complete prescribed engine failure vital action checks from memory;
- complete the emergency drill, in accordance with the emergency checklist;
- complete engine shutdown checks and other necessary checks in accordance with the appropriate emergency checklist(s).
- monitor the operating engine and take appropriate action to keep the operating engine parameters within limitations.
This is perhaps the most important exercise of the multi-engine flight test—it is certainly the most challenging. It examines the scenario whereby the pilot is on final approach—i.e., the flaps are fully extended, the gear is down, and airspeed is back at Vref—and, for some reason, an overshoot is required; just after power is added, one of the engines fails. The pilot must therefore keep the aircraft under control, prevent unnecessary altitude loss, identify and feather the bad engine, and successfully establish a climb at Vyse.
One would initially think that the requisite for this exercise is lots of coffee, but keep in mind that the exercise is really not a lot of work. The power settings for the go-around, for example, are all in place, so that when the overshoot/engine failure occurs, you simply have to advance both throttles, keep the aircraft straight with aggressive rudder, retract the flaps, raise the gear, identify the bad engine, verify it is bad, and then feather its propeller. A cause check is not required—only a fire check must be completed.1
The key to this exercise is airspeed management. When the need for overshoot is apparent, simply add ½ and then full power, as you would normally do. Then place the aircraft in a 5° pitch-up attitude, taking the steps necessary to recover the flaps and gear. Your procedures should be identical to those followed in an overshoot.
The only difference with this overshoot is that—at some point during the overshoot sequence—one of the engines will fail.2 When this happens, there are only two things that are crucial to remember. First, don’t stop your normal overshoot routine—keep following and complete the overshoot sequence. So often, students encountering this engine failure become immediately distracted and abandon the normal overshoot routine—crucial seconds are lost, and the cost is delayed climb performance. Remember the first two actions of a pilot faced with an engine failure—other than “control,” which is of course assumed—are “power” and “drag.” For any overshoot, this is naturally part of the sequence, and these items are therefore already covered. Secondly, take action to “stop the climb” and conserve altitude until the engine has been feathered. This is obvious, but it is worthwhile emphasizing. In the normal overshoot, the pilot smoothly raises the nose to a 10° pitch-up attitude, but if this same action is taken with a failed and non-feathered engine, a close encounter with the Vmc red line is imminent. The question is, then, what are you supposed to do with pitch in such a situation? The answer is that, until the bad engine is identified and feathered, pitch should be adjusted to simply maintain altitude.3 This maintaining of altitude is required for only a few seconds—while you identify, verify, and feather the offending engine—and any speed bleed during this time will be minimized as maximum power of the good engine has already been applied, and all drag has been minimized. Once feathering is accomplished, the pilot can smoothly negotiate blue-line Vyse.
As you can see, then, airspeed management is king here. The idea, of course, is to get on to the blue line as quickly as possible, but remember that you have to transition to blue line from what is initially a low-energy state—low power, low speed (90 MPH), an approach (descending) attitude, and all that drag (flaps, gear, and an unfeathered propeller). In short, the aircraft will be a dog in the classic sense of the word! Faced with this, does it make sense to rapidly make the transition from the descending attitude to the climb attitude? No it does not, because if you try to get the climb pitch happening with one continuous pitching-up change, you will surely decelerate through that small margin of 10 MPH and into the realm of Vmc, and that is not good. Instead, make it your goal to simply stop the descent. Once you have completed the sequence and the engine is feathered, you can then (and only then) raise the nose up to produce the blue line climb.
How does that saying go?—“. . where the pitch goes, the airspeed will follow.” If you jerk around with the pilot inputs during this exercise, you will be making it extremely difficult for yourself. Since you are in a transition with respect to pitch—from a descending attitude to, at least initially, a levelling attitude—the primary reference is the altimeter.4 To make effective sense of the altimeter, however, you must be firm but smooth with the control. Don’t try to pre-empt the movements of the aircraft caused by the failure. Let the aircraft show you its thing first, and then you smoothly input what you want it to do.
You can’t ignore airspeed, but remember the ASI is not the immediate priority the instant the engine fails—control pitch first, and then examine where you are at on the airspeed indicator. The control responsiveness of the aircraft is telling you how close you are to Vmc—if you find yourself requiring full- or near full-deflection inputs, then you know instantaneously that you are too close to the red line and that you must, therefore, immediately (but smoothly) back off on the pitch and, if necessary, back off the power (for Vmc protection).
Keeping the aircraft straight is a critical first-response to the failure. Be sure, however, not to try to pre-guess which way the nose will yaw—the resultant effect will simply be unproductive jerks on the rudder pedals. Instead, let the aircraft show you which corrective rudder is required. It is equally important to respond with aileron inputs—once the aircraft shows you its yawed condition, smoothly roll opposite to the yaw until the 5° counter-bank is established. With this done, the aircraft will become far more efficient, and far more passive and easier to handle.
What happens if your weight and/or altitude don’t let you climb at blue line and you begin to descend? Flying the blue line is the best you can do, and you have no choice but to maintain blue line with the anticipation of descending into more effective thicker air.
With respect to the spontaneous vital actions you must perform—control, power, drag, identify, verify, feather, blue line, fire check—it is crucial that you do not interrupt the flow. Keep the vital actions moving, despite the distraction of the failed engine. And think how really simple it is. Control, for example, is automatic. Power is already in place because you have initiated an overshoot. Drag too is part of the overshoot routine. The only variation, then, is identify, verify, and feather. So get to the knee slap—for identify—as quickly as possible, and the verify and feather will follow naturally.
The only remaining yet necessary action to do—after aircraft recovers from its dangerously close proximity to the ground—is fire-check the bad engine—a mere visual inspection of the bad engine’s nacelle. The fire check should not be done until the immediate danger of close proximity to terrain is dealt with—when the propeller has been feathered and you are establishing the aircraft in a blue-line climb. If a fire is indicated, proceed accordingly.
Note that if vital-actions flow breaks down for students, it typically occurs when the right hand moves from the throttles—after applying maximum power—to the flaps—to begin the drag recovery. This is, incidentally, the time at which the Examiner closes one of the throttles to simulate an engine failure. A second likely breakdown of the flow occurs after the drag actions—flaps and gear—are completed. Too often, students then say “control . . power . . drag . .” and this, of course, is wasted dialogue—appropriate enough, however, if there is any confusion (as it makes you cover all vital action). The students who are successful at maintaining flow move automatically from the gear handle to the knee-slap.
It may be worthwhile to emphasis that you shouldn’t let your language slow you down in this sequence—so often students’ hands know what to do, but the hands are waiting for the brain and mouth to spit out the word.
Advance knowledge of how this exercise is set up in training and during the ride is important. The Examiner will likely set up a scenario for you to work through. Commonly, for example, the Examiner may ask you to set up an approach on to a field—acting as the simulated runway. Once you have established the aircraft in the final approach configuration—including the speed reduction to Vref—you will be asked to “pull up and go around.” After your hand is removed from the throttle, the simulation will occur. Examiners (and Instructors) like to assign an altitude as the factitious runway elevation, so that you can gauge how effective the overshoot is—the overshoot is typically initiated only 200’ above the imagined runway surface.
You will see that it is sometimes more effective for you to set up “zero-thrust” which simulates the engine failure (rather than the Instructor or Examiner). To do this—undertaken after you say “feather right (or left) engine”—simply retard the throttle smoothly to just above the gear horn, and reduce the appropriate propeller control by approximately ½ its travel. The Examiner or Instructor will then fine-tune the settings.
This exercise entails a prolonged descent, so be sure a carefully clearing turn is conducted before commencing.
You will be very close to Vmc in this exercise, and with the non-failed engine developing full power. Throughout the overshoot manoeuvre, guard Vmc—should Vmc symptoms appear, be ready with the counter-Vmc responses discussed earlier.
Just a reminder—be sure to only simulate vital actions.
It is extremely productive to conduct this exercise in the circuit at Langley Airport, with the overshoot initiated approximately 500’ AAE on final approach. This is usually done under intense scrutiny by the Instructor, and only after you have been familiarized with the exercise at altitude in the practice area. In the circuit at Langley
Airport, it is common for helicopters to be training on the non-circuit side of the runway centreline—be sure not to let the aircraft drift. If you have any doubt, simply abort the exercise.
1 Just in case a fire is associated with the engine failure.
2 In training, your Instructor will retard one of the throttles to idle, simulating the failed engine.
3 This will require some pitch-up inputs, obviously—but the pitch-up required is far less than required to produce a climb.
4 Just as the altimeter is the primary reference for pitch when levelling at the top of a climb, or the bottom of a descent.