Flying a Manual Go-around
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Flying a Go-Around places special demands on the pilots, especially when the Go-Around is unexpected.
This article deals with the underlying technique for flying a manual Go-Around.
The following general points are aimed at Multi Crew operation but they also serve as good reminders of the self-discipline required if operating single pilot.
- Briefing – The key building block for flying a successful Go-Around is a good briefing. This should cover normal Go-Around and how a Go-Around above Decision Altitude and/ or Acceleration Altitude might be handled. This could usefully be revised at a quiet moment during the approach so that actions are clear in everyone’s mind, should they be needed.
- Complacency – It is tempting in good weather, particularly on last sector into home base not to bother with detailed thinking about a Go-Around. There have been several potentially serious incidents caused by such complacency. A Go-Around can be triggered at any time. The more unexpected and more unprepared crew members are, the more likely that serious error will occur. Research indicates that those who make use of mental rehearsals of possible actions make fewer errors than those who don’t.
- Priorities – It is important in a Go-Around that crew members deal with the primary flight task first and secondary tasks afterwards. The priority is to get the aircraft climbing away from the ground at an appropriate attitude, in the right configuration, at the right speed with appropriate power set. It is always surprising to watch crews carrying out a Go-Around make an R/T call during the manoeuvre and arrive at Acceleration Altitude with the wrong configuration/ speed/ power.
- Standard Procedures – using Standard Operating Procedures and Call-Outs can help trigger all the appropriate actions. It is easy to use non-standard calls and discover later that some important triggers for flap and gear retraction have been missed. It also needs careful thought when carrying out a Go-Around from an unfamiliar position such as above D. Alt or Acceleration Altitude that Standard Calls such as 'Go-Around - Flap xx' do not trigger an inappropriate flap movement if the flaps are not in the landing setting.
- Missed Approach Altitude - It is important to consider the Missed Approach Altitude when discussing how to handle a Go-Around. A low Missed Approach Altitude will require careful and thoughtful handling of power, acceleration and clean up to avoid an altitude bust.
Go-Around from above Decision Altitude
In training, most Go-Arounds are commenced at or near Decision Altitude. A G/A flown due to bad wx has usually been anticipated & briefed. It is the G/A flown in ‘good’ wx (perhaps due to ATC) or the G/A is commenced from a point other than DA, which usually presents the greatest problems. Pilots should be mentally prepared to be told to Go-Around from any point on the Approach, even from above the Go-Around Altitude. Practice in flying a Go-Around is normally included in routine refresher training and analysis of Flight Data Monitoring data indicates a need for practice in flying Go-Arounds flown from above Decision Altitude/Height as well as the more commonly practiced Go-Around from DA/H.
Transition to Instrument Flying
If the Go-Around is conducted because of weather conditions, the transition to instruments will require particular attention. The Go-Around procedure may be further complicated if airspeed and/or thrust setting are low. See the separate article "Go-Around - Transition to Instrument Flying". Many airlines use a procedure (particularly in poor weather conditions) where the non-landing pilot will fly the approach down to Decision Altitude with the specific intention of going around at Decision Altitude unless they have a clear call of the decision to continue the approach and take control from the Landing Pilot. This can make both acquisition of the required visual reference easier and obviate the necessity of the pilot flying the Go-Around from making the transition from instruments to visual and then back to instruments if a Go-Around is flown.
All Engines Go-around
Many modern aircraft have an automatic facility whereby the aircraft automatic systems accomplish the transition from approach to Go-Around by power and attitude adjustment. However, not all aircraft have this facility; moreover, there is a need for pilots of aircraft which do have automatic Go-Around capability to maintain proficiency in this procedure in case manually reversion should be necessary.
An All Engines Go Around will typically be executed when the aircraft is relatively light, at least below Maximum Landing Weight, and so when Go Around thrust is applied performance may well be brisk - if you are not careful, not only will you climb with a very high v/s, you will accelerate rapidly through all the flap limiting speeds. One major manufacturer limits the rate of climb to 2,000 feet per minute because of this (Even so, this assumes that pitch & speed are correct; if pitch is low, thrust will increase up to full GA thrust and the a/c will rapidly accelerate, but a ROC of 2000fpm will not be achieved.). Aircraft SOPs must take precedence but it is worth remembering that the aircraft will be much more manageable when reducing to Climb Thrust (but will still accelerate faster than on a normal take-off due to reduced weight). Furthermore, careful consideration needs to be given to how this can be handled as, if Go Around Thrust (TOGA) is never selected, the FMS Flight Plan and electronic checklist (ECL) may not sequence as expected or correctly.
PF must be ready for any pitch up effect that is much more marked with all engines operating than on the Engine Out Go-Arounds practised in the simulator. FBW a/c may automatically trim out any pitch/power couple, so it is necessary for the PF to make a positive rotation manoeuvre (pull-up) to place the a/c in the correct G/A attitude. In all cases, pilots should recognise (and resist) the pitch-up illusion created by rapid acceleration.
The most important element of handling a Manual Go-Around is selecting the correct power and pitch attitude to enable the Go-Around to be flown at the correct speed. Knowing the appropriate figures will help in flying an accurate profile. Because of the high power settings involved in a Go-Around it is interesting to see how often when the speed starts to run away how many pilots, at this time of very high workload, intuitively try to control the speed by reducing power rather than with pitch attitude. This often reduces power to a level that can seriously degrade climb performance causing potential Obstacle Clearance problems.
Go-Around from Non-standard Speed or Configuration
The regulator mandates that crews demonstrate, in the simulator, competence at go–round from Decision Minima, when the aircraft is close to Vref and has drag flap deployed. This is fine but in real life many go-rounds are flown much earlier in the approach, prior to full flap selection and potentially close to flap limit speed to maintain separation from the following aircraft. These are rarely practiced in the sim – there is barely enough time to do the mandated items, never mind gain some handling experience - and invariably they lead to speed limits being exceeded or level busts. Crews should give some thought to how they would manage a Go-Around at all stages of an approach, including the following:
- It may be appropriate to consider continuing down the approach path, if legally permitted, for a few moments whilst the handling of the Go-Around and the configuration is discussed before being actioned.
- Going around from above the missed approach altitude may require the pilot to level off and maintain their current altitude or a modified altitude as instructed by ATC.
- In congested airspace the missed approach altitude, track and speed is usually mandated. This can be a complicated affair if the Go-Around instruction or decision is made above the mandated missed approach altitude.
- To ensure correct sequencing and compliance with the Go-Around procedure in FMS equipped aircraft it is often advisable (if conditions allow) to continue on the approach until the aircraft descends below the missed approach altitude before selecting TOGA.
- Relying on LNAV for the lateral part of the Go-round guidance can create a significant problem if the FMS flight plan legs have not sequenced correctly prior to initiating the G/A, then the lateral path of the G/A is likely to flown incorrectly.
"The pilot flying (PF) is responsible for controlling vertical navigation and lateral navigation, and for energy management, by ... Flying manually, with flight director (FD) guidance and an adapted (e.g., horizontal situation indicator (HSI) - type) navigation display (ND) mode.
"The PNF is responsible for monitoring tasks and for conducting actions requested by the PF, including:
- Conducting the standard PM tasks; ...
- Monitoring the thrust setting;
- Monitoring vertical speed and radio-altimeter altitude; and,
- Monitoring pitch attitude, bank angle, airspeed and airspeed trend, and calling out any excessive deviation."
The briefing note then provides a thorough explanation of the flight dynamics of a go-around, which is important for understanding the interaction between changes to engine power and flight control settings.
If a Go-Around is flown using F/D crews should be aware of exactly what is being commanded in roll and pitch. For example some F/D will command a heading that maintains aircraft track as at the moment Go Around was initiated (which, particularly if correcting localiser deviation at the time, may be very different from the required track during the Go Around manoeuvre). Adherence to SOPs will help ensure that appropriate modes are selected to command appropriate track and vertical profiles. Particularly after a Non Precision Approach in poor weather, the landing pilot can experience very high workload in trying to manoeuvre the aircraft for landing. The PM plays a vital role in monitoring this phase of the approach and calling for a Go-Around if stabilised approach criteria are not met or if unhappy with the manoeuvre. A good briefing can be very helpful in setting expectations/ bottom lines to inform these decisions.
There is often strong emphasis on flying a go-round manually. Nonetheless, the maximum use of the autopilot will reduce pilot workload, aid monitoring capacity and go a long way to ensuring a successful outcome to any Go-Around.
Flying a Manual Go-Around
This is a very demanding manoeuvre and in real life is often accompanied by extra stress due to the bad weather or traffic problems that caused it. Crews should take any opportunity in the simulator to practice it with all engines operating as well as mandated engine-failed training.
"For a safe go-around," the FSF briefing note continues, "the following “three Ps” constitute a golden rule:
- Set and maintain the pitch-attitude target;
- Set and check the go-around thrust; and,
- Check aircraft performance: positive rate of climb, airspeed at or above Vref (reference landing speed), speed brakes retracted, radio-altimeter indications and barometric-altimeter indications increasing, wings level, gear up, flaps as required.
Go-rounds should never be met with any kind of negative feedback. Previous accidents have revealed pilots being reluctant to Go-round because they had been criticised for doing so earlier. In a large fleet, there will always be some pilots who have done more Go-rounds than others, as explained by the ‘Law of Large Numbers’ (which shows that some lottery numbers occur more than 4 times as often as others and, when plotted, fit under a normal distribution curve.
Go-Around Safety Forum
- Go-Around Safety Forum (GASF), Brussels 2013: Findings and Conclusions
- "Do you really understand how your trim works?" - Captain Alex Fisher
Flight Safety Foundation
- ALAR Briefing Note 6.2 — Manual Go-around contains a thorough discussion of the manual go-around.
Airbus Descent Management Briefing Notes