Autopilot Mismanagement & Meet The “Snitch”

by Michael J. “Mick” Kaufman
Published in Midwest Flyer – February/March 2017 issue

After finishing my column for each issue of Midwest Flyer Magazine, I often wonder what I should write about in the next issue. A few days after finishing the last issue, I received a phone call about a recent accident, and my investigation began with a new hot topic. A few days after that, I received another phone call from a reader, which started topic #2: “Meet the Snitch.”

Autopilot Mismanagement

I call the first topic “Autopilot Mismanagement,” because it was pilot induced and was the cause of three fatal accidents killing six people within a very short period of time. Two of those accidents were in Bonanzas and one involved a Cessna 182, and they all had different autopilots. The latest accident occurred in Concord, Calif., involving a Bonanza, and my company (BPT, Inc.) had just held a pilot recurrent training program there several weeks prior. The pilot of this fatal accident was not one of our program participants. The common denominator of all of these accidents involved “electric trim” with the pilot trying to override the trim.

The first accident occurred in the Orlando, Fla. area as a pilot with one passenger took off from a satellite airport and unknowingly climbed into the overlying Class B airspace. Air traffic control contacted the pilot on the radio to advise him of his altitude deviation, and the pilot began to push forward on the yolk to correct the deviation and get below the airspace. The autopilot was on, and you may be able to guess what happened next. Before we continue with this sad story, let’s review some autopilot theory.

Most autopilots have two servos – one to control pitch and one to control roll – and some autopilots also have a yaw servo if the aircraft needs a little help to smooth out the ride in turbulence as my V-tailed Bonanza does. For this topic, we will be concentrating on that pitch servo and assume that the autopilot has electric trim. We need to mention that electric trim is not necessarily part of the autopilot as many aircraft have electric trim and no autopilot.

When electric trim is installed and integrated into the autopilot system, its purpose is to help the pitch servo overcome excessive force on the controls when needed. If we are trying to hold an altitude and the aircraft flies into some sinking air (sink happens, a glider pilot term), the pitch servo applies up elevator pressure to keep from losing altitude. If too much up elevator travel is needed, or if it should be needed for an extended period of time, such as reducing airspeed with the throttle by the pilot, the pitch servo then calls for help. The help comes from the electric trim as you can visually see the trim wheel move as it relieves the force on the pitch servo.

This is a good spot in the article to make a short topic change to teach a basic instrument skill. We can learn this trim concept from the autopilot when hand flying on instruments. Many times I see pilots, when hand flying the airplane, constantly re-trim the aircraft every time it feels slightly out of trim due to turbulence. Take note that the autopilot electric trim only comes into play when there is a great need to do so. The pilot should act much as the pitch servo does by pushing or pulling on the yoke to maintain altitude and trim only as the last resort.

In the accidents that we are talking about, the autopilot would need to be in a pitch or altitude hold mode. If the pilot were to push forward on the yoke to descend below the Class B airspace, the autopilot pitch servo would call for help and trim the aircraft nose up. This is what happened and, eventually, we have full-up trim and the pilot can no longer overpower the trim. We now have what is called a “trim tab stall,” which in this case, most likely ended up in a spin, followed by a crash in the lake.

All three of these accidents mentioned here occurred because of the trim control being all the way against the stop due to autopilot/electric trim mismanagement where the pilot could not override this condition. Each accident claimed two lives and could have been prevented.

A pilot needs to know the aircraft he/she is flying and the different ways to disconnect the autopilot or electric trim in case of a runaway. Most aircraft have a double safety feature on the electric trim when using it manually. This can be a split switch that requires the pilot to apply thumb pressure on both halves of the switch to activate the desired electric trim. Other manual electric trim switches require a push in the direction and a push downward simultaneously to activate. Another option not seen very often is a single button that has no up or down button, but trims to relieve pressure on the yoke. Using this system, the pilot simply pushes or pulls on the yoke and then pushes the single button and the trim relieves the pressure similar to the autopilot calling for help.

We must learn not to manually try to fight the autopilot as the electric trim will fight back and in the cases we just mentioned, the pilot lost. On some autopilots, if the autopilot is on and we manually touch the electric trim, the autopilot comes off line. On others, there is a separate button on the yoke, many times in red, that disconnects the autopilot. Sometimes that disconnect button is on the instrument panel, which hopefully is in a good viewing position for the pilot.

If you have a “go-around button” as part of a flight director, it should also disconnect the autopilot (servos only). A circuit breaker for the autopilot or electric trim is another means of disconnecting, but I think it is a poor one, as finding it in an emergency situation is difficult, unless it is well marked. A good choice if you are not having good results would be to shut off the master switch. You will lose everything electric, but the engine will still run…at least on all of the airplanes I fly.

Learn your autopilot well and the test and disconnect methods. The FAA has set up guidelines for avionics shops, but they do not always follow them and sometimes they don’t make sense, or there are installation mistakes.

Meet The Snitch

The second topic, “Meet the Snitch,” leads us into a third topic that will follow about airspace and altitudes. I remember from grade school that a snitch was someone who told the teacher on you when you did something wrong or naughty. Sometimes, the snitch remains anonymous, as I never found out who snitched on me in my fifth grade class.

I received a phone call from a reader in mid-November wanting some advice. The pilot received a phone call from a local FAA inspector a few days earlier claiming he violated airspace during an approach to Hagerstown, Md., six (6) months earlier. The pilot was flying his own personal twin-engine aircraft at the time, and the only thing he could recall after that much time had past, was that the approach was down to weather approach minimums.

The pilot was an AOPA member and had bought the legal protection plan through AOPA, so he called them for legal advice. AOPA legal protection told him he was the victim of the “snitch.”

The snitch, they explained, is a computer that analyzes the ADS-B data from the aircraft, and computer data on airspace, looking for errors. There was never a deviation reported by air traffic control of a violation. Upon receiving the initial call from the inspector, the pilot refused any comment until he got legal advice from an attorney. After receiving advice, the pilot called the inspector and asked if he was the victim of the snitch. The inspector’s response was that he believed that is what the FAA is calling it.

What we know about the snitch, as of this writing, is that it has only been installed in Potomac Approach’s airspace and targets aircraft with ADS-B equipment. The pilot had installed this new ADS-B equipment less than a year prior to the incident to comply with FAA’s 2020 mandate. Any of our readers who have also been the target of the “snitch,” are encouraged to contact me so we might have more information to pass on to our readers.

It is a sad scenario when an aircraft owner goes to the expense of installing ADS-B equipment to comply with FAA’s 2020 mandate with the intent to improve airspace safety, only to become a victim of the equipment when there is clearly no intent to violate an airspace restriction. Let’s hope the FAA rethinks their “snitch” tactics and enforcement policies.

FIG 1 - For Illustration Only! Chart Not To Be Used For Navigation

Many times pilots asked me about the altitudes they should be flying on a particular instrument approach, and there is a lot to be said about this subject. For the purpose of this article, we are going to be using the ILS 27 approach to Hagerstown, Md. (FIG 1), as this was the approach referenced when discussing the “snitch.”

There are some magical, and sometimes confusing, words when the controller’s voice comes through the radio with “cleared for the approach.” These words may be in conjunction with other words or restrictions which we need to take into consideration with this approach clearance, mainly being at which point does this clearance take effect.

Let’s take vectoring into consideration and use the clearance example “Cessna 2852 Foxtrot, you are 3 miles from PODUK. Turn left heading 030. Maintain 3,400 till established. You are cleared for the ILS 18 approach to Happy Town.”

Other than reading back the clearance, this is an easy one. After turning to 030 degrees, we wait for the localizer needle to move, intercept the course, fly the needle and wait for the glide-slope needle, assuming it is above us and follow it down to the decision altitude published on the chart.

The next scenario we will use will be on the approach chart for Hagerstown (FIG 1), and we are approaching the airport IFR from the northwest and receive the following clearance from Potomac approach:

“Cessna 22 Hotel Bravo, you are cleared for the ILS 27 approach to Hagerstown via the St. Thomas transition. Proceed direct St. Thomas. Maintain 7,000 till established on a segment of the approach.”

You look at the approach chart and find St. Thomas (THS), a VOR northwest of the airport, and turn to your VOR (NO GPS) to the proper frequency and head toward it. You are a bit confused as you study the approach chart, but see an arrow pointing in the direction of the initial approach fix with a direction of 118 degrees, and you think this is what the controller meant.

If you have one of those nice GPS boxes, things are much easier. On the Garmin 430/530, you have the airport (KHGR) loaded as your destination, you select approach and pick the ILS 27, and then select the transition, which is THS. You are done with your route except for altitudes.

Thinking about altitude, you remember two things from your clearance: 1) “Cleared for the approach,” and 2) “Maintain 7,000.” As you cross the St. Thomas VOR (THS), you are now established on a segment of the approach because there is an altitude published.

So, you begin a descent to 4,200 feet, as that was published on the chart. You look down at the approach chart and in the lower right-hand corner of the top view of the approach, you see a circle that is divided into segments labeled “MSA” and there are several altitudes shown. You also notice that the circle shows a 25NM distance from MRB, and there is a VOR symbol. That must mean these altitudes pertain to distance from the Martinsburg VOR, but you do not see it depicted on the approach chart. Now you remember your old flight instructor telling you that the MSA circle altitudes are not to be used, and are a reference only for an emergency.

You are now on your way to the HAIGS intersection at the altitude of 4,200 feet and see a holding pattern course reversal there. You are a bit confused again as the HAIGS intersection has an IF/IAF printed above it, and you are wondering what that means and what should be done next. The IAF means the first time you cross the intersection, it is considered the initial approach fix (IAF). The second time you cross it would make it the intermediate fix (IF), followed by the final approach fix (FAF) at NOLIN. The chart shows that once you have crossed the HAIGS fix the first time and in the course reversal, you may descend another 200 feet to 4,000.

At this point if I were flying this approach and were receiving the localizer/glide-slope, I would wait for the glide-slope to center and follow it down to my decision altitude (DA). This would eliminate making a step-down to 2,900 to cross the final approach fix and give me more time to get stabilized on the glide-slope.

I am always saddened to read that so many accident reports are the result of controlled flight into terrain (CFIT) because the pilot did not understand the clearance or the approach chart. The scenario I created for this approach is just one of many we could explore, and it is highly impractical getting such a clearance so far out on the approach to an airport like Hagerstown, unless it was 3:00 a.m. on Christmas Eve, but it would be quite common in Cut Bank, Montana. I see the need for me to write more on altitudes that need to be understood, and flown on approaches, in future issues of Midwest Flyer Magazine, and I will do so.

It is “icing season” again. Stay away from icing conditions unless you have the proper de-icing equipment, and always plan an out to get clear of the ice.

EDITOR’S NOTE: Michael J. “Mick” Kaufman is a Certified Instrument Flight Instructor (CFII) and the program manager of flight operations with the “Bonanza/Baron Pilot Training” organization. Kaufman conducts pilot clinics and specialized instruction throughout the U.S. in a variety of aircraft, which are equipped with a variety of avionics, although he is based in Lone Rock (KLNR) and Eagle River (KEGV), Wisconsin. Kaufman was named “FAA’s Safety Team Representative of the Year” for Wisconsin in 2008. Email questions to captmick@me.com or call 817-988-0174.

DISCLAIMER:
The information contained in this column is the author’s opinion only, and readers are advised to seek the opinion of their personal flight instructor and others before attempting any procedures discussed herein.

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