Category: AOPA

FIKI

Basics of the aircraft deice and anti-ice systems

Icing is one of the mostly daily occurrences of line flying. Since it’s often unavoidable, aircraft are equipped for flight into known icing conditions. That is to say, the aircraft has been tested and certified for flight into areas where icing conditions are known to exist. Since the day that mail began flying instead of riding the rails, the business goal has been to have a consistent and reliable schedule. The ability to fly into known icing is a critical component of scheduled service.

With most turbine aircraft, hot compressed air is drawn from the engine into an elaborate ducting system that leads the hot air to wing leading edges as well as engine nacelle lips and the horizontal stabilizer. This air is dubbed “bleed” air as it is “bled” from the engine core. Turbine aircraft often have many uses for this bleed air: pressurization, air conditioning, engine starting, and anti-icing.

When required, this extremely hot air can be tapped from the engine core and led to critical flight surfaces for anti-icing and deicing requirements. This can generally be done either manually or via automatic activation. Ice detector probes are designed in such a way that icing will form first on the probe. This probe is designed to vibrate at a specific frequency and when ice has accreted on its surface, that frequency of vibration changes. The system recognizes the ice buildup and, depending on the configuration of the system, it activates the anti-icing system. You can manually activate the system without the use of the detector probes.

During winter operations it’s often required that aircraft be deiced before takeoff. Remember you should never attempt to take off with snow, frost, or ice crystals adhering to the aircraft. The entire aircraft should be clean of contamination prior to takeoff—not just the control surfaces, or the wings and tail. This protects the aircraft during takeoff and initial climb. It can often be a two-part process: deicing the aircraft to remove contaminants, then a coating of anti-icing fluid. The latter is almost always required when freezing conditions are present and there is precipitation.

Combining the ice protection systems and the deicing and anti-icing technologies, we are able to provide safe and comfortable transport through the most inhospitable conditions.

Transitioning from simulator to real world

The first time I flew a Transport-category aircraft, there were 50 people sitting comfortably in the back. I tried hard to not really think about it, but it’s hard to ignore. It was my first day of initial operating experience, or IOE. I had spent nearly two months training in a classroom and simulator, but this was the beginning of my actual aircraft training.

Much like almost any training program, there was a ground school, a written test, an oral exam, and a practical test in a simulator. Ground school covered all the aircraft systems, basic regulations, and company operations specifications. Simulator training consisted of basic instrument flying skills, emergency drills, and normal line flying. The checkride itself included items straight from the Airline Transport Pilot Practical Test Standards.

After completing the training program, I was scheduled for IOE with a company line instructor for two four-day trip sequences. It was his job to help consolidate my training and ensure that after all that training in the simulator, I could actually fly the aircraft. He would mentor and instruct me on the procedures.

At first the workload seems immense, and you wonder how you will ever get everything done on time—then it slowly eases. Everything you learned in ground school and in the simulator still applies, but now the time crunch is on. After day two or three I was starting to get my preflight preparations completed with time to spare.

It was during these first few days that the differences between flying the simulator and flying in the real world became dramatically apparent. Nuances of the airplane that couldn’t be duplicated, delays inherent to the system that required quick surmounting, dealing with passenger issues, baggage-handling delays—and most of all, weather.

Once I had completed a second four-day trip, my instructor signed me off for line flying. Unlike most certificates or ratings that only require the written, oral, and practical test, becoming a line-qualified FAR Part 121 pilot also requires this signoff. It’s like the final endorsement and seal of approval. It was like being given that first signoff for solo flight. I felt as though I was taking that first step alone. It’s an experience that I keep reliving in my flying career.

Visual Approach clearances

Of all the approach clearances you will hear as a line pilot, "Cleared for the visual" is likely to be the most often received.

How many visual approaches did you do during your primary flight training? Sure, everyone has done traffic patterns, and perhaps a few straight-in landings. What about a visual approach to a runway 10 miles away from 8,000 to 10,000 feet? Not straight-in, either, but from a base leg or downwind?

A simple technique I employ uses aiming points, descent planning, and energy management. Everyone has used aiming points on runways to gauge and manage glide and flight path while on final approach. Simply use this same technique to landmarks along your flight path toward a runway.

A desirable glidepath angle of 3 degrees yields 300 feet of descent per nautical mile (actually 333 feet, yet we will use 300). Imagine then you are on a 5-mile base leg to the runway at 3,000 feet. Visually follow where you expect your flight path to carry you on final, and trace it backwards to your current position. Identify significant landmarks such as a lake, large building, road crossing. Using this technique, select an aiming point around a 3-mile final at approximately 900 feet agl. This is the point where you should plan to be on final, configured for landing, on glidepath and approach speed. Each mile hence, backwards from this point, add 300 feet.

Aim not at the runway, but at the specified aiming points along the path to the runway. Knowing that at each specific point you plan on arriving at 1,500 feet, 1,200 feet, 900 feet, etc. By selecting more points, it is easier to identify and correct any deviations from the desired path. I use the glideslope intercept altitude, or the altitude at which the flight path angle begins. This will be around 5 miles from the approach end of the runway and commences a 3-degree descent to the runway. Exact accuracy isn‘t required; however, being within a few hundred feet of an on-glide indication is still attainable.

To add energy management and configuration to the technique, simply add a target to each aiming point. For example, on a 6-mile base, plan on being configured at 200 knots and approach flaps. On a 4-mile base, gear down, landing flaps, 150 knots. Joining final, approach speed and any final configuration changes.

The practical test standards outline all of the required and recommended items for every check ride you will take in the span of your flying career. Each contain specific tasks and elements that cater to whatever certificate or rating your being tested for, however they all contain essentially the same special emphasis areas. The special emphasis areas are the catch all for general practices and techniques not specifically called for in the tasks and area of operation. Often they are overlooked in check ride preparation, yet can be just as devastating to a successful check ride as a failed task.

Often times applicants don’t even know that the special emphasis areas exist until pointed out by the examiner. It’s often an excellent idea to begin a students new phase of training with a thorough discussion of the elements of the PTS. Included in this discussion should be a review of the special emphasis areas common to all practical tests, as well as any new or different ones the student may not be familiar with.

Collision avoidance is a popular complaint among examiners for many different reasons. Students failing to properly clear the training area prior to beginning maneuvers can create collision hazards. Unreasonable focus inside the aircraft at primary instruments or other cockpit distractions lead to loss of positive aircraft control, and sometimes unusual attitudes.

Spin awareness has always been an area of focus for flight instructors to teach and examiners to test. It’s imperative to teach the student to the correlation level of learning in regards to spin awareness. Often times students are able to define what a spin is and how it occurs, yet they can’t connect the concepts they’ve learned to scenarios in which they could encounter a spin. The fated base to final turn over shoot is the most common and should be an easy connection for any student. Ensure they have the knowledge of the aerodynamics, yet emphasize the stick and rudder of a spin. It’s always best for a student to experience the incipient and even fully developed spin if you have an aircraft and equipment for it.

Runway incursion avoidance has statistically been the leading cause of pilot deviations for years. The FAA has put intense emphasis on this subject in an effort to decrease this, however, it remains to be an issue with pilots of all experience levels. The easiest way to decrease your susceptibility to runway incursions is to practice sterile cockpit below 10,000 feet for turbine aircraft, and anytime the aircraft is below the planned cruise altitude for light airplanes. Recently the FAA changed the way you will get taxi clearance to cross runways. You will no longer receive a taxi clearance to cross more than one runway, active or not. Hopefully this will help decrease confusion over a crossing clearance.

Remember that each rating or certificate contains specific and sometimes different items on the special emphasis area. It’s important to review them for each practical exam you’re preparing a student for. Examiners are impressed upon to test these special emphasis areas throughout the practical exam, and often times they will use distractions of some sort to incite them. It’s imperative to create scenarios that adequately test and train these skills. It is almost guaranteed that a student will get a scenario as described on a practical exam.

Why are you getting your instrument rating? Probably because it's a stepping stone to a commercial or maybe even a CFI certificate. Maybe because you own your own airplane and are looking to gain some extra flexibility when it comes to cross country flying. Whatever the reason, gaining an instrument rating will increase your confidence and accuracy of flight by reference to the instruments. One of the largest benefits being the ability to conduct instrument approaches.

Now instead of canceling your flight because of low visibility or low ceilings, you will be able to utilize an instrument approach and land hassle free. What comes from your training with a flight instructor in preparation for this rating will be basic attitude instrument flying, tracking and intercepting of navigation aids, holding, and instrument approaches. Along with the flying portion of your new rating, there are a lot of new applicable regulations to be familiar with.

Of the regulations, one in particular stands out as a common misunderstanding and is one often misinterpreted. 91.175(c) talks about operating an aircraft below the published minimums for an instrument approach. In order to continue flight below these minimums there are several conditions you have to meet.

First and foremost is keeping the aircraft in a position that will allow a normal landing using normal maneuvers and normal rates of descent. The FAA doesn't want you to arrive at the missed approach point, directly over the runway threshold at 800 feet, and attempt to land the aircraft on the 3500 foot runway. Consider that you will be in low visibility conditions, making a rapid descent to a runway that could potentially 'disappear' at any time in the low visibility or cloud layers.

Next they require that the visibility is not less than the prescribed minimums on the approach procedure. It's important to also keep in mind what they don't mention here. Ceiling. There is no mention of a ceiling requirement. Often times students believe that the minimums include visibility and the ceiling. If the MDA or DA is 200' and the ceiling is at 100', there is no legal restriction as long as you have at least the minimum visibility required being reported.

Now we get into the tricky part of this easily confused regulation. I often posed this question in oral exams to students. “What can I do if I arrive at DA on an ILS and I have the approach lights in sight, but I can't yet see the runway?” Often times I heard a recital of all the items listed that are required to be visible and distinctly identifiable. Threshold, threshold markings, threshold lights, runway end identifier lights, etc. They recited this list from rote memory because they were taught that if they don't see one of those items from the list, they have to execute a missed approach.

The truth is, if you arrive at DA or MDA with the approach lights in sight, you are legally allowed to continue a descent to 100 feet above the published touchdown zone elevation using the approach light system as a reference. Now if you begin your descent below the DA or MDA and begin to identify the runway, or any listed item, you can continue to land. Think of the approach light system as an aid in the transition from instrument flight to visual flight. They are the link between the two, and should be used as such.

Now a caveat to that is also mentioned in the regulation. It says you may descend to 100 feet above the touchdown zone UNLESS the red terminating bars or red side row bars are also distinctly visible and identifiable. What does that even mean?

What it should say is: If the runway the approach is serving has an ALSF-I or ALSF-II approach light system, visual contact with the red side row bar or red terminating bar authorizes you to continue the descent to land. You do not have to stop at 100 feet above the touchdown zone. Currently the only two approach light systems in the US that include the red side row and red terminating bars are the ALSF-I and the ALSF-II. Keep that in mind when you brief the approach, look at the approach light system so you know what to look for, and so you know what you will do when you get to DA or MDA.

You are getting your instrument rating to increase your ability to complete flights in lower than VFR weather conditions, complete understanding and application of this regulation will help you meet that goal.