This is the fifth in a series of articles dealing with learning to fly a Technically Advanced Aircraft (TAA).  By definition, TAA does not imply a glass cockpit, but a glass cockpit does imply a TAA since almost 90% of production aircraft rolling off the assembly lines of the 5 largest general aviation manufacturers have glass cockpits that meet the TAA definition.  FT decided to devote a series to helping you learn most efficiently and most effectively in the TAA trainers that you are likely to encounter at your local airport.  Ed

 

In part 4, we discussed learning the Technically Advanced Aircraft (TAA) autopilot systems and how the pilot must stay proficient in understanding the various modes of the models installed in their aircraft.  We found that there are two classes of autopilots used in TAA aircraft; analog and digital, and that each were considered capable but the digital units achieved a far more robust level of integration with the glass panel.  Modern TAA aircraft are loaded with systems which are intended to keep the pilot alert and aware of their surroundings and ready to meet conditions of an emergency.  Unfortunately, this robustness also implies a responsibility of the pilot to know and understand all of these systems so that they are properly utilized in the event of an emergency.  This installment will describe a sampling of systems provided for pilot safety and offer some practical advice for pilots so they are prepared to use these systems at the right time and in a way that will really help them deal with the emergencies.

 

 

One of the realities of aviation is that it is an activity that involves risk.  There are a number of types of risk that we have to deal with; unforeseen weather, tricky winds, unexpected mechanical issues of the aircraft, and destination airports that have challenging logistics all rate high on the list of things the pilot must consider prior to any flight.  A “good pilot is a prepared pilot” is my motto and you should consider it as yours, too.  In other words, we must anticipate that things could go wrong and we should prepare for these as best we can.  Face it, nobody starts out on a flight wanting something to go wrong, but that does not stop it from becoming your reality when you least expect it.  System failures can be classified into a number of categories: abnormal conditions and emergency conditions are the two most common categories used and there is usually a checklist for each type of anticipated failure within each category.  Just because the manufacturer of the aircraft constitutes an occurrence as an abnormal situation does not mean that it is not an emergency when it occurs to you.  You are the pilot in command and it is up to you as to how you will handle it.  Time is normally a critical factor in emergency response.  The longer a pilot waits after first discovering a problem, the higher the likelihood that it will get worse rather than better.  Pilots have been known to become so distracted addressing a failure that they have lost control of the aircraft.  Don’t be one of these statistics.  You should not handle it alone.  Remember Apollo 13.  You should be like them.  Involve others.  Confess your predicament to ATC.  Pull out the manual.  Do what ever you have to but don’t wait and hope the situation gets better on its own.  It won’t.

 

 

There are a number of things that the pilot can do to prepare for the unexpected so that their ability to react appropriately is bolstered by experience.  One of the things that really can help is a thorough knowledge of emergency responses to challenges which can arise in the TAA cockpit.  Since the nature of these systems is that they are computers running software and this software depends upon a whole host of sensors and signals from other devices to provide a fully operational experience, it stands to reason that there is risk of failure in more ways than might be expected from a conventionally equipped aircraft.   Manufacturers of these aircraft have spent considerable time and money convincing the FAA that their systems are dependable, but the FAA has been watching “dependable systems” fail for unexpected reasons for many years.

 

One of the most common problems that a pilot can experience is a failure of an alternator or loss of electrical power.  Since just about every TAA aircraft comes equipped with 2 batteries and may come with a backup alternator, one would imagine that the risk has been mitigated by the manufacturer.  This is only partially true because many of these systems are designed to only provide an electrical backup for a portion of the electrical system, not all of it.  Let me explain.  The electrical system is divided into what are referred to as electrical “busses”.  These busses are literally a subdivision of electrical components or appliances that are powered from a common set of circuit breakers.  An example is an “avionics bus”.  With the push of an avionics master switch, power is applied to a set of circuit breakers allowing power to flow to all of the appliances attached to that bus.  Aircraft typically have at least two busses in the electrical system: Main and Avionics.  TAA aircraft are typically divided into three: Essential Bus, a Main bus, and an Avionics bus.  Pilots need to understand how these components function and interrelate in order to be able to respond to a failure or degradation.  A TAA aircraft will typically send power to all the Busses when the battery and the Alternator are functioning properly.  Should a failure occur such as the loss of an alternator, the aircraft will need to be reconfigured so that the main battery is not being used to power the entire aircraft.  In a TAA aircraft such as a Cessna, they use a smaller 24 volt battery to serve as a backup for the Essential Bus in the event of an alternator failure.  This is great, but the pilot must know that if all other power was exhausted from the remaining main battery, the standby battery can ONLY power the Essential bus and cannot provide any power to the main bus.  What this means is that if a pilot exhausts the main battery first after an alternator failure, the backup battery cannot power any lights, flaps, boost pumps, pitot heat, landing gear or any avionics that is not connected to the Essential bus.  Oops.  This information would be helpful to know on a night flight.  It would be better to exhaust the backup battery first and then reengage the primary battery for the landing so flaps and lights could be used at the end of the flight.  This information is hidden in the manual.

 

Another emergency that the pilot needs to be prepared for is the loss of Primary Flight Display (PFD).  On an Avidyne Entegra or a G1000, the loss of a PFD will manifest itself to the pilot in the same way (black screen) but must be handled in different ways.  Why?  In both cases, the PFD contains all primary heading and pitot-static related information such as airspeed and altitude.  It also contains the primary information on the horizontal situation indicator (HSI) that the autopilot uses for following the flightplan.  A G1000 has a failover mode that automatically sends the PFD information to the MFD in the event of a sensed PFD failure and it has a red reversionary button which allows the pilot to do this on purpose.  This is great for the pilot because they simply have to look over to the MFD and continue to fly the aircraft.  A total failure of the PFD on an Avidyne equipped aircraft such as the Cirrus or a Piper results in the pilot being forced immediately to refer to the standby instruments, especially if flying at night or in IFR.  There is no red button.  In this case, the pilot may use the GNS 430 to control the autopilot and continue to fly the flightplan for the trip, but has lost the PFD display information, perhaps for the rest of the flight.  Make sure that you put the autopilot in GPSS (GPS Steering mode) by pressing NAV twice.  If the PFD on the Avidyne has failed and cannot be brought back to life by a quick restart (pulling the circuit breakers (yes, there are two not one) and resetting within 10 seconds) it is recommended that the pilot pull both circuit breakers to the PFD and isolate it completely.  Remember the autopilot is chasing the CDI needle on the HSI and in this case, the pilot does not know what the HSI is saying because it can’t be seen.  Follow the checklist.  It contains the tested procedures for most kinds of failures that the pilot could encounter.

 

 

Another failure that can occur on these aircraft is a failure of the autopilot or the trim system.  In installment 4, we talked about the autopilot and the fact that it consists of a control box and a number of different interfaces to servos and the TAA PFD screen itself.  This constitutes a wide variety of potential for the system to misbehave.  Pilots should monitor the autopilot for potential problems.  Typically, small red lights of P, R, or PT illuminated in red, or any kind of flashing indication on the control head or along the top of the PFD is an indication to the pilot that “George” is in trouble.  Sometimes the pilot can restore the system by turning it off and then reinitializing it.  Sometimes turbulence can throw the pitch channel into a tizzy and a circuit breaker pull may be the only remedy to restore the system.  The pilot should know the autopilot systems down cold and should practice overpowering the system by manually exerting force on the controls to wrestle control of the aircraft back in the event of a runaway servo.  Instructors should practice autopilot stall recoveries with students to make sure they can recognize and recover from an autopilot induced stall. 

 

One thing that pilots need to know is that when a failure like this occurs, there are things they can do to help themselves.  One thing a pilot can do is to try to reset the component.  Sometimes this can be done by resetting a circuit breaker and sometimes there is another way to reset the component through a software switch.  The important thing to do is to be methodical and stay calm.  When a failure strikes, reach for the checklist, control the aircraft, and start a logical troubleshooting process.  Try to figure out exactly what happened.  Find out if it is something simple first.  Failed screens could be caused by a bumped cabin lighting knob or it could be something more.  Eliminate the simple explanations first.  Don’t become involved trying to troubleshoot something that is unimportant to your flight.  If a circuit breaker pops, smell for burning or any visible smoke.  If so, then the game is over, forget the component until you are on the ground.  Don’t try to reset a component that could start a fire.  Breakers don’t pop for no reason, but I have seen breakers pop caused by a failure in the breaker itself.  Either way, you are allowed a single attempt to reset a breaker of a needed component.  If it pops right back out again, then forget it.  Fly the aircraft.  Devise an alternative plan.  Start looking for options.  If you just departed on your trip, consider returning to your home base.  If you are almost to your destination, consider your risks of continuing to that destination with the degraded systems.  If the odds are in your favor, then so be it.  If the odds are against you, then immediately consider your closest alternative by pressing the NEAREST button on your GPS.  When selecting an alternative airport, consider whether that airport has sufficient services to service your TAA aircraft.  In a real emergency such as an engine failure, low fuel warnings, or warnings related to oil temperature and pressure or fuel pressure, then consider that the nearest airport may be your only option.  Don’t pass up a perfectly good airport only to make a landing on a highway 6 miles later.

 

Conclusion

 

You should now have a better understanding of the emergencies a pilot needs to be prepared for in a glass cockpit aircraft such as the Garmin G1000 and the Avidyne Entegra.  The pilot must learn the procedures for addressing a variety of system failures and must become completely skilled at emergency operation modes.  Flight instructors must test pilots’ ability to respond quickly to a variety of issues that can arise.  A good instructor should always be asking questions of the student regarding potential failure scenarios.  A good scenario always starts with the word “suppose”.  The pilot will find that the skillful response to potential failure conditions will be predicated on their continual review of the POH and the checklist.   A lucky pilot may spend their entire flying career without suffering a catastrophic failure, but a skillful pilot will spend their entire flying career preparing for the day when luck runs out.  I would rather be skillful than lucky any day.   Q