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CFI Brief: NextGEN Modernization

On Tuesday the FAA published a new video to FAA TV, NextGEN: See, Navigate, Communicate. If you are not familiar with NextGEN, it is simply the modernization of the National Airspace System (NAS). The short 6 minute video discusses the current challenges to the NAS and how NextGEN is overcoming these challenges with a total revamping of the system. Check out the video, what are your thoughts about NextGEN?

NextGen is the modernizing of the National Airspace System. We are creating a system that will change how we see, navigate, and communicate with aircraft and manage our skies. Find out why these changes are critical in enabling us to accomplish our mission.

NextGen is the modernizing of the National Airspace System. We are creating a system that will change how we see, navigate, and communicate with aircraft and manage our skies. Find out why these changes are critical in enabling us to accomplish our mission.

 

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Communication Procedures: Communication at Airports with Operating Towers

We’ve talked a lot about communications so far on the Learn to Fly Blog. Today we’ll get into communications at towered airports. This post comes from the latest edition (twelfth!) of Bob Gardner’s essential flying textbook The Complete Private Pilot.

Airspace around an airport with an operating control tower is Class D airspace (unless it is within Class B airspace); it will usually extend vertically to 2,500 feet above airport elevation and horizontally a nominal 4.4 nautical miles (the boundaries may vary, but will be charted). If you need to enter Class D airspace, you must first communicate with the tower. If you are departing, you must first receive taxi instructions (not a “taxi clearance”) from the ground controller, who directs all activity on the ramps and taxiways. With few exceptions, ground control operates on 121.6, 121.7, 121.8, or 121.9 MHz. Controllers will frequently shorten this by eliminating the 121: “Contact ground point seven leaving the runway.”

The ground controller will authorize you to taxi to the runway in use, but you must stop before crossing any taxiways or runways (active or not) and receive permission to cross. Think of it as a stoplight at every intersection that glows red until the controller turns it to green. The figure below illustrates a situation where a pilot taxiing from the ramp to the runup area for runway 9 would receive authorization for the whole route, but would be told to hold short of runway 27. With permission to cross, he or she would proceed to the unmarked intersection with the closed runway, stop, call for permission, and the procedure would be repeated at the hold lines for runways 36R and 36L. It is the controller’s responsibility to issue precise instructions, but if you are getting close to any kind of intersection without having heard from the tower, stop and ask.

Taxiing to the active runway.

Taxiing to the active runway.

Note: Ground controllers do not use the word “cleared,” because it might be misconstrued as a takeoff clearance…they say “taxi to” or “taxi across.” If you are directed to “hold short” of a runway you must read that instruction back to the controller verbatim…nothing else will suffice. To avoid a runway incursion, always stop and ask for clarification of any instruction you do not understand. “What do you want me to do?” works just fine.

If you are at an unfamiliar airport, do not hesitate to ask for “progressive taxi instructions” and the controller will guide you to your destination on the field. “Student pilot” is a useful phrase to include in your transmissions.

When you are ready for takeoff, contact the tower controller for takeoff clearance. The tower (or “local”) controller is responsible for all aircraft in Class D airspace and on the active runway—don’t taxi onto the runway without a clearance. You must maintain communication with the tower controllers while you are in their airspace (Class D), but remember that separation from other airplanes is your responsibility; don’t expect the controller to keep you from swapping paint. When you have departed Class D airspace you are on your own (or you may request radar services). You do not have to ask the tower for permission to change frequencies after you have crossed the Class D airspace boundary.

On arrival, before you enter Class D airspace you should listen to the ATIS (if there is one) and advise the tower controller on initial contact that you have the ATIS information. Where there is no ATIS, listen on the tower frequency and note the instructions given to other pilots. Once you are sure of the runway in use, wind, and altimeter setting, you can say: “Miami Tower, Baron 2345X ten miles west with the numbers.” After landing, do not change to ground control until advised to do so by the tower. Some tower-controlled airports have UNICOM, but because you will get all of your weather information and clearances from the tower, your use of UNICOM at that tower-controlled airport will be limited to such things as calling for fuel, ordering rental cars, etc. Note: Towers report wind direction relative to magnetic north. In fact, any wind direction you receive by radio is referenced to magnetic north; winds in written form, such as forecasts, are referenced to true north.

If you have any questions about how your flight was handled by the tower, call as soon as practicable and talk to a quality assurance person before the tapes are erased—don’t expect an answer if you wait more than 15 days.

If an airport does not have an ATIS and does not use the primary control tower frequency as the CTAF, its data block will include “VFR Advisory—125.0”; if, of course, 125.0 is the frequency to use.

We’ll be back on Thursday with more from our CFI. If you’d like to receive new posts by email, subscribe using the form at the top of the sidebar to the right!

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CFI Brief: Pilot’s Role in Collision Avoidance

With all the talk this week on instrument flying and scanning techniques I wanted to take this opportunity to remind you to get your head out of the cockpit. See and Avoid! Did you know that the See and Avoid concept is an actual regulation outlined in CFR 91.113? Don’t believe me check it out. The reg basically states that when weather conditions permit, regardless of IFR or VFR, it is each pilot’s responsibility to see and avoid other aircraft.

This is the perfect time to review a pilot’s role in collision avoidance. On Tuesday, the FAA released an update to Advisory Circular 90-48. I encourage you to spend some time reviewing it. AC 90-48D provides a wealth of information alerting pilots to the hazards of midair collisions and potential midair collisions. Topics covered include: human casual factors, improvements in pilot education, operating practices, procedures, and improved scanning techniques to reduce midair conflicts.

The FAA reports that over a five year span from 2009 – 2013 49 midair collisions and 461 near midair collision occurred within the United States. Statistical analysis has always pointed toward the fact that the majority of all midair collisions occur in good weather (VFR) during daylight hours. Reading through this AC will help provide you with the knowledge and information so as not to become a statistic. Click the image below to view the full NTSB report on this August 8th, 2009 midair collision between a Piper and Eurocopter.

Midair Collision over the Hudson River, New York.

Midair Collision over the Hudson River, New York.

One piece of information that I find particularly insightful from the AC is the table below, which shows the average person’s reaction time to traffic movement.

Table 1 Reaction Time

12.5 seconds may seem like a very quick reaction time but in reality it’s an eternity when aircraft are closing in on one another at a combined 300 knots. This is why it is so important to use proper visual scanning techniques and identify a potential traffic conflict as early as possible.

AC-90-48D PDF

AC

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IFR: Attitude Flying and Applied Instrument Flying

This week we’re back on the topic of IFR flight. If you’ve missed our previous posts touching on IFR, check out these posts:

We’ve also written extensively on the flight instruments themselves too, all of which you can find here. Today’s post comes from The Pilot’s Manual: Instrument Flying (Volume 3).

The first step in becoming an instrument pilot is to become competent at attitude flying on the full panel containing the six basic flight instruments. The term attitude flying means using a combination of engine power and airplane attitude to achieve the required performance in terms of flight path and airspeed.

Attitude flying on instruments is an extension of visual flying, with your attention gradually shifting from external visual cues to the instrument indications in the cockpit, until you are able to fly accurately on instruments alone.

Partial panel attitude instrument flying, also known as limited panel, will be introduced fairly early in your training. For this exercise, the main control instrument, the attitude indicator, is assumed to have malfunctioned and is not available for use. The heading indicator, often powered from the same source as the AI, may also be unavailable.

Partial panel training will probably be practiced concurrently with full panel training, so that the exercise does not assume an importance out of proportion to its difficulty. You will perform the same basic flight maneuvers, but on a reduced number of instruments. The partial panel exercise will increase your instrument flying competence, as well as your confidence.

An excessively high or low nose attitude, or an extreme bank angle, is known as an unusual attitude. Unusual attitudes should never occur inadvertently but can result from distractions or a visual illusion. Practice in recovering from them, however, will increase both your confidence and your overall proficiency. This exercise will be practiced on both a full panel and a partial panel.

After you have achieved a satisfactory standard in attitude flying, on both a full panel and a partial panel, your instrument flying skills will be applied to en route flights using navigation aids (NAVAIDs) and radar.

The full panel (left) and the partial panel (right).

The full panel (left) and the partial panel (right) in a glass cockpit.

Procedural instrument flying (which means getting from one place to another) is based mainly on knowing where the airplane is in relation to a particular ground transmitter (known as orientation), and then accurately tracking to or from the ground station. Tracking is simply attitude flying, plus a wind correction angle to allow for drift.

Typical NAVAIDs used are the ADF, VOR, DME and ILS, as well as ground-based radar. In many ways, en route navigation is easier using the navigation instruments than it is by visual means. It is also more precise.

Having navigated the airplane on instruments to a destination, you must consider your approach. If instrument conditions exist, an instrument approach must be made. If you encounter visual conditions, you may continue with the instrument approach or, with ATC authorization, shorten the flight path by flying a visual approach or a contact approach. This allows you to proceed visually to a sighted runway.

En route tracking on instruments.

En route tracking on instruments.

Only published instrument approach procedures may be followed, with charts commonly used in the United States available from the FAA or Jeppesen. An instrument approach usually involves positioning the airplane over (or near) a ground station or a radio fix, and then using precise attitude flying to descend along the published flight path at a suitable airspeed.

Left: plan and profile views of a precision instrument approach (NACO chart). Right: plan and profile views of a nonprecision approach (Jeppesen chart).

Left: plan and profile views of a precision instrument approach (NACO chart). Right: plan and profile views of a nonprecision approach (Jeppesen chart).

If visual conditions are encountered on the instrument approach at or before a predetermined minimum altitude is reached, then the airplane may be maneuvered for a landing. If visual conditions are not met at or before this minimum altitude, perform a missed approach. The options are to climb away and position yourself for another approach, or to divert elsewhere.

It is important psychologically to feel confident about your instrument flying ability in an actual airplane, so in-flight training is important. There will be more noise, more distractions, more duties and differing body sensations in the airplane. G-forces resulting from maneuvering will be experienced, as will turbulence, and these may serve to upset the inner senses. Despite the differences, however, the ground trainer can be used very successfully to prepare you for the real thing. Practice in it often to improve your instrument skills. Time in the real airplane can then be used more efficiently.

Editor’s note: We will continue to expand on these principles in Thursday’s post and in later ground school posts. If you’re starting to think about getting your instrument rating, or are already flying with one, check out ASA’s selection of books on airmanship. For private pilots I would recommend IFR for VFR Pilots by Richard Taylor, Instrument Flying Refresher by Richard Collins and Patrick Bradley, and A Pilot’s Accident Review by John Lowery. Instrument rated pilots should check out Flying IFR and ATC & Weather: Mastering the Systems by Richard Collins, and Severe Weather Flying by Dennis Newton. We’ll see you Thursday.

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CFI Brief: It’s sunny and 80°F, why do I need a weather brief?

I did the majority of my flight training in San Diego, CA. Yes, lucky me. Not only did I get to fly in such a beautiful area but I always had a killer tan. After my first week of ground school, my instructor had me get my first over-the-phone weather briefing. That day in class we had just gone over how to obtain a weather briefing, so logically I figured he was testing me to see how much of the information I absorbed and retained. Over the next couple of days before each flight he had me do the same. I began to wonder…does this guy not look outside? It’s still 80°F and sunny, not a cloud in the sky, just like yesterday, and the day before that. It wasn’t until our discussion on regulations that I realized, this was an actual requirement for flying. The FAA requires you to obtain weather information if you plan on flying outside the vicinity of the airport. As training continued, I began to realize the importance and responsibility of obtaining accurate weather information no matter how sunny and clear it appears to be and not just because it’s a regulation.

7_Day_Beach_640x480

I bring this personal story up because today I want to discuss 14 CFR §91.103, “Preflight action”, which reads:

“Each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight.”

Basically as pilot-in-command (PIC) you cannot just hop in the plane and go. It doesn’t matter if you’ve conducted the same flight 100 times in the past; you still need to familiarize yourself with all available information for this particular flight. The regulation goes on to further break down exactly what information you must obtain:

(a) For a flight under IFR or a flight not in the vicinity of an airport, weather reports and forecasts, fuel requirements, alternatives available if the planned flight cannot be completed, and any known traffic delays of which the pilot in command has been advised by ATC;

(b) For any flight, runway lengths at airports of intended use, and the following takeoff and landing distance information:

(1) For civil aircraft for which an approved Airplane or Rotorcraft Flight Manual containing takeoff and landing distance data is required, the takeoff and landing distance data contained therein; and

(2) For civil aircraft other than those specified in paragraph (b)(1) of this section, other reliable information appropriate to the aircraft, relating to aircraft performance under expected values of airport elevation and runway slope, aircraft gross weight, and wind and temperature.

This is essentially the regulation in its entirety. To make this regulation little easier to understand let’s map it out in a more logical way.

Today I plan on conducting a flight as PIC from Bellingham Airport (BLI) in Northern Washington state to Seattle’s Boeing Field (BFI). Based solely off 14 CFR §91.103, I would need to obtain and determine the following (and from the following sources):

  • Weather reports and forecasts (800-WX-BRIEF or www.1800wxbrief.com)
  • Fuel requirements (POH/AFM for the aircraft I’m flying)
  • Alternate airports (Sectionals, TAC, and/or Airport/Facility Directory)
  • Known traffic delays (NOTAMs, TFRs, ATIS)
  • Runway length at airports of intended use (Airport/Facility Directory)
  • Takeoff distance (POH/AFM + weather briefing)
  • Landing distance (POH/AFM + weather briefing)

My first order of business is to obtain weather reports and forecasts. The regulation does not specifically state, but this should include information for arrival and departure points as well as en route. Next I need to determine fuel requirements. How much fuel is needed to get to BFI? I want to account for possible weather, known traffic delays and be sure to meet VFR day or night fuel reserve regulations. With fuel in mind, I want to determine availability of alternate airports. You always want to have a backup plan if for some reason you can no longer land at your planned destination. Just like you would for you destination airport, become familiar with any alternate airports you may choose. This leads us into runway lengths at airports of intended use. We want to gather this data for both BLI and BFI. It’s also a good idea to have this information on hand for the alternate airport(s) we have chosen. Lastly, we need to determine performance for takeoff and landing distances. This is to ensure we have selected airports that have sufficient runway lengths. Remember, performance data can change due to environmental conditions, so an airport that might have sufficient runway length one day may not the following day (think wind, density altitude, runway surface conditions, etc).

As you can see there is a lot of information you need to gather before each flight. One way to keep track of all this information is to use an ASA Flight Planner form. In addition to the actual flight plan, you have a note section to jot down performance data and a terminal information section to list runway lengths and other airport information such as communication frequencies. On the backside is where you have a dedicated section for Preflight Pilot Checklist, Weight and Balance, and the ICAO Flight Plan form.

Now, by no means am I saying this is all that needs to be accomplished prior to taking flight, this is just the minimum as outlined in 14 CFR §91.103.

So when your instructor tells you to do something, there’s usually a pretty good reason behind it.

 

 

 

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Regulations: 14 CFR 91.13 and 91.15

Today we have more regulations that every pilot needs to know. Bob Gardner provides an excellent list of summarized federal regulations for student pilots in his textbook The Complete Private Pilot. If you’re looking for the compendium of aviation regulations, check out our annually-relased FAR/AIM. These summaries are taken from the latest edition of The Complete Private Pilot.

14 CFR 91.13 Careless or reckless operation. This is a catch-all regulation. If you have any type of accident or incident, the assumption is that you must have been either careless or reckless. Your responsibility is to leave nothing to chance: use written checklists rather than rely on memory. As pilot-in-command, do not let anyone interfere with your control of the airplane.

14 CFR 91.15 Dropping objects. You may not drop or allow to be dropped from your aircraft any object that creates a hazard to persons or property. If reasonable precautions to avoid injury or damage are taken, dropping objects is authorized. Make sure that your proposed drop does not violate any state or local laws…strewing the ashes of a decedent is unlawful in many jurisdictions.

cfrcomics

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CFI Brief: Parasite and Induced Drag

Monday’s post touched on the topic of aerodynamics, specifically drag. As you can imagine, drag is an extremely crucial part of flying and also one of the four forces acting on an aircraft in flight (Thrust, Drag, Weight, Lift). Today I want to briefly cover and test your knowledge on the two types of drag: parasite and induced. If you have not yet read Monday’s post I would suggest you do so prior to continuing with today’s CFI Brief, all the answers to these question can be found within that post.

Let me start off by posing the question, what is parasite drag?

Parasite drag is the resistance of the air produced by any part of an airplane that does not produce lift (antennae, landing gear, etc.). Parasite drag will increase as airspeed increases.
For example, if you were to throw both a coffee cup and baseball through the air, the baseball would create less parasite drag because it’s shape is more aerodynamic then a coffee cup. The faster you throw each of those objects the more parasite drag they would produce.

What is induced drag?

Induced drag is a by-product of lift. In other words, drag is induced as the wing develops lift. The high-pressure air beneath the wing, which is trying to flow around and over the wing tips into the area of low pressure, causes a vortex behind the wing tip. This vortex induces a spanwise flow and creates vortices all along the trailing edge of the wing. As the angle of attack is increased (up to the critical angle), lift will increase and so will the vortices and downwash. This downwash redirects the lift vector rearward, causing a rearward component of lift (induced drag). Induced drag will increase as airspeed decreases.

The figure below is a common one in which you will see throughout your pilot training. It will help you visualize the relationship of airspeed to both parasite and induced drag, resulting in total drag from the two.

Drag vs Speed

1. What are the three types of parasite drag?
a. Induced, Form, and Skin Friction
b. Form, Interference, Skin Friction
c. Interference, Induced, and Form

2. What is an example of interference drag?
a. The intersection of the wing root to the fuselage.
b. The wing creating lift.
c. The rough surface of the wings.

3. As airspeed decreases induced drag
a. remains the same.
b. will decrease.
c. will increase.

ANSWERS

  1. Answer choice B is correct; form, interference, and skin friction are the three types of parasite drag.
  2. Answer choice A is correct. If you choose answer B this would be an example of Induced Drag. Answer choice C while it is parasite drag would better fall under the category of skin friction.
  3. Answer choice C is correct. Remember induced drag is a byproduct of lift, as the aircraft slows the wings will need to produce more lift to maintain altitude.
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Aerodynamics: Drag

This week on the Learn to Fly Blog we’re talking about drag. One of the four forces of flight, drag opposes thrust and at rearward parallel to the relative wind. We’ll get more into the practical application of your understanding of drag on Thursday with our CFI, but today we will define the two types of aerodynamic drag: parasite drag and induced drag. Today’s post features excerpts from the Pilot’s Handbook of Aeronautical Knowledge (8083-25).

Parasite Drag
Parasite drag is comprised of all the forces that work to slow an aircraft’s movement. As the term parasite implies, it is the drag that is not associated with the production of lift. This includes the displacement of the air by the aircraft, turbulence generated in the airstream, or a hindrance of air
moving over the surface of the aircraft and airfoil. There are three types of parasite drag: form drag, interference drag, and skin friction.

Form Drag
Form drag is the portion of parasite drag generated by the aircraft due to its shape and airflow around it. Examples include the engine cowlings, antennas, and the aerodynamic shape of other components. When the air has to separate to move around a moving aircraft and its components, it eventually rejoins after passing the body. How quickly and smoothly it rejoins is representative of the resistance that it creates which requires additional force to overcome.

Form drag.

Form drag.

Notice how the flat plate in Figure 4-5 causes the air to swirl around the edges until it eventually rejoins downstream. Form drag is the easiest to reduce when designing an aircraft. The solution is to streamline as many of the parts as possible.

Interference Drag
Interference drag comes from the intersection of airstreams that creates eddy currents, turbulence, or restricts smooth airflow. For example, the intersection of the wing and the fuselage at the wing root has significant interference drag. Air flowing around the fuselage collides with air flowing over the wing, merging into a current of air different from the two original currents. The most interference drag is observed when two surfaces meet at perpendicular angles. Fairings are used to reduce this tendency. If a jet fighter carries two identical wing tanks, the overall drag is greater than the sum of the individual tanks because both of these create and generate interference drag. Fairings and distance between lifting surfaces and external components (such as radar antennas hung from wings) reduce interference drag.

A wing root can cause interference drag.

A wing root can cause interference drag.

Skin Friction Drag
Skin friction drag is the aerodynamic resistance due to the contact of moving air with the surface of an aircraft. Every surface, no matter how apparently smooth, has a rough, ragged surface when viewed under a microscope. The air molecules, which come in direct contact with the surface of the wing, are virtually motionless. Each layer of molecules above the surface moves slightly faster until the molecules are moving at the velocity of the air moving around the aircraft. This speed is called the free-stream velocity. The area between the wing and the free-stream velocity level is about as wide as a playing card and is called the boundary layer. At the top of the boundary layer, the molecules increase velocity and move at the same speed as the molecules outside the boundary layer. The actual speed at which the molecules move depends upon the shape of the wing, the viscosity (stickiness) of the air through which the wing or airfoil is moving, and its compressibility (how much it can be compacted).

The airflow outside of the boundary layer reacts to the shape of the edge of the boundary layer just as it would to the physical surface of an object. The boundary layer gives any object an “effective” shape that is usually slightly different from the physical shape. The boundary layer may also separate from the body, thus creating an effective shape much different from the physical shape of the object. This change in the physical shape of the boundary layer causes a dramatic decrease in lift and an increase in drag. When this happens, the airfoil has stalled.

In order to reduce the effect of skin friction drag, aircraft designers utilize flush mount rivets and remove any irregularities which may protrude above the wing surface. In addition, a smooth and glossy finish aids in transition of air across the surface of the wing. Since dirt on an aircraft disrupts the free flow of air and increases drag, keep the surfaces of an aircraft clean and waxed.

Induced Drag
The second basic type of drag is induced drag. It is an established physical fact that no system that does work in the mechanical sense can be 100 percent efficient. This means that whatever the nature of the system, the required work is obtained at the expense of certain additional work that is dissipated or lost in the system. The more efficient the system, the smaller this loss.

In level flight the aerodynamic properties of a wing or rotor produce a required lift, but this can be obtained only at the expense of a certain penalty. The name given to this penalty is induced drag. Induced drag is inherent whenever an airfoil is producing lift and, in fact, this type of drag is inseparable from the production of lift. Consequently, it is always present if lift is produced.

An airfoil (wing or rotor blade) produces the lift force by making use of the energy of the free airstream. Whenever an airfoil is producing lift, the pressure on the lower surface of it is greater than that on the upper surface (Bernoulli’s Principle). As a result, the air tends to fl ow from the high pressure area below the tip upward to the low pressure area on the upper surface. In the vicinity of the tips, there is a tendency for these pressures to equalize, resulting in a lateral flow outward from the underside to the upper surface. This lateral flow imparts a rotational velocity to the air at the tips, creating vortices, which trail behind the airfoil.

When the aircraft is viewed from the tail, these vortices circulate counterclockwise about the right tip and clockwise about the left tip. Bearing in mind the direction of rotation of these vortices, it can be seen that they induce an upward flow of air beyond the tip, and a downwash flow behind the wing’s trailing edge. This induced downwash has nothing in common with the downwash that is necessary to produce lift. It is, in fact, the source of induced drag. The greater the size and strength of the vortices and consequent downwash component on the net airflow over the airfoil, the greater the induced drag effect becomes. This downwash over the top of the airfoil at the tip has the same effect as bending the lift vector rearward; therefore, the lift is slightly aft of perpendicular to the relative wind, creating a rearward lift component. This is induced drag.

A wingtip vortex from a crop duster.

A wingtip vortex from a crop duster.

In order to create a greater negative pressure on the top of an airfoil, the airfoil can be inclined to a higher AOA. If the AOA of a symmetrical airfoil were zero, there would be no pressure differential, and consequently, no downwash component and no induced drag. In any case, as AOA increases, induced drag increases proportionally. To state this another way—the lower the airspeed the greater the AOA required to produce lift equal to the aircraft’s weight and, therefore, the greater induced drag. The amount of induced drag varies inversely with the square of the airspeed.

Conversely, parasite drag increases as the square of the airspeed. Thus, as airspeed decreases to near the stalling speed, the total drag becomes greater, due mainly to the sharp rise in induced drag. Similarly, as the airspeed reaches the terminal velocity of the aircraft, the total drag again increases rapidly, due to the sharp increase of parasite drag. As seen in the chart below, at some given airspeed, total drag is at its minimum amount. In figuring the maximum endurance and range of aircraft, the power required to overcome drag is at a minimum if drag is at a minimum.

Drag versus speed.

Drag versus speed.

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CFI Brief: Heading to a Fly-In this year?

This week kicks off airshow and fly-in season with SUN ‘n FUN International Fly-In and Expo being held in Lakeland, FL. The event began on Tuesday and will conclude on Sunday with the mass exodus of hundreds of general-aviation aircraft. In advance of this year’s fly-in season the National Transportation Safety Board has issued a safety alert (SA-053). The NTSB occasional issues these Aviation Safety alerts as well as videos in an effort to improve safety while providing safety related suggestions to the aviation community. If you plan on attending any fly-in’s this season I would highly recommend you take the time to read through SA-053, aptly titled “Arriving at a Major Fly-In Event? Keep your focus on safety”.

Also, if you are not already aware most fly-in’s will issue both Arrival and Departure procedures for aircraft in an effort to increase safety and decrease air traffic congestion. These procedures can usually be found on the fly-in’s website. Along with reviewing fly-in procedures it is also imperative that you check NOTAM’s.

Below is an excerpt of SA-053, the full Safety Alert can be viewed by following this link.
SA-053
The problem

  • Arrivals at major fly-in events, such as SUN ‘n FUN and Experimental Aircraft Association (EAA) AirVenture, pose unique challenges for pilots (and air traffic controllers), including extremely high-density traffic, special flight and communication procedures, a rapidly changing environment, and changes to air traffic control (ATC) separation standards.
  • ATC standards for such events allow reduced runway separation between aircraft, minimized radio communications between pilots and ATC, and shared control of arrival and departure aircraft on the same runway between different teams of controllers. Thus, pilots can be as little as 1,500 ft behind another aircraft landing on the same runway (typical separation standards require 3,000 ft between aircraft), and ATC may be communicating with arrival and departure aircraft on different frequencies, reducing their ability to assess the traffic situation. Pilots may focus so much on complying with ATC instructions in this challenging environment that they lose control of the aircraft, which can lead to a stall.
  • Accidents have occurred when pilots were too slow and stalled, used an excessive bank angle (resulting in an accelerated stall), or overshot the runway (resulting in a cross-control stall) when turning from downwind to base leg or from base leg to final.
  • Pilots may not adequately review Federal Aviation Administration (FAA) notices to airmen (NOTAMs) published for the events. These NOTAMs are critical to ensuring flight safety because they contain special operational procedures, including arrival and departure routes, communication procedures, and other crucial safety information.
  • The major fly-in event environment, with hundreds or thousands of people watching, may create pressure for pilots to continue an approach that they are uncomfortable with rather than go around. Several preventable loss-of-control accidents have occurred on arrival to such events because pilots have inadvertently exceeded their own performance limitations or those of their aircraft while operating in these unique environments.
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The Top 10 Mistakes Students Make on Their Practical Test

Today we’re pleased to feature a guest post from CFI and DPE Jason Blair. Check out his previous contributions to the LTFB here. He writes his own blog at JasonBlair.net

As an examiner who gives a significant number of practical tests every year, I see some of the same errors over and over. Being prepared for a test takes a lot of work, but some extra focus on a few of these areas can reduce the chances a student’s test will end the bad way.

The following are a few very common things I see that result in notices of disapproval on multiple practical tests every year.

Getting lost. It seems improbable, but many times a year I see people get lost during their practical tests. A pilot should remain cognizant at all times of their position and able to navigate back to the airport they started at without incurring any other airspaces along the way using charts not GPS to get home).

Short-field landings. Test standards require a pilot be able to perform short-field landings to a point without being short and within a specified distance beyond the point for each test. Landing short of or excessively beyond the point is something that causes pilots to regularly fail tests. Know the standard, be able to perform to the standard, and be willing to go-around if you aren’t going to land within the standard.

Soft-field takeoffs. Even though many pilots have never landed on grass or other soft-field conditions, pilots must demonstrate the maneuver on multiple tests. Many pilots are unable to demonstrate a soft-field takeoff, in many cases they’ll even accidentally strike the tail in the process. This will always result in an automatic failure.

Busting airspace. This relates to getting lost, but it also stretches to knowing airspace implications and limitations. While I say busting airspace commonly is a failure point, it is probably best described as “almost busting” airspace. An examiner won’t let you actually break the airspace, but will typically stop you just prior to the violation. I have to do this multiple times a year and it is an automatic failure. Know what airspace is in effect where you are flying, and be aware of horizontal and vertical limitations of that airspace. Knowing where you are at all times will add to the ability to avoid incurring airspace unintentionally.

Incorrectly following ATC instructions. If flying at an airport or in airspace that requires coordination with ATC, failure to follow ATC instructions or coordinate with them can lead to a fast end to a test. It is equally important on the ground as it is in the air. More than a few tests have ended because an applicant could not follow or did not understand taxi instructions. Pattern and vectoring instructions are also critical. If you don’t understand or are unclear what ATC wants, ask for clarification or for them to repeat the clearance. Being humble and admitting you didn’t understand is always better than ending up where you aren’t supposed to be or incurring other traffic. The best advice I can always give is to write it down. Even the best of us forget what ATC said, but having it written down on our kneeboard can be a quick memory refresh.

Not going around. No pilot flies the perfect approach every time. No, an examiner won’t allow you to go-around all day, but making a good decision on an approach and going around when landing isn’t going to be within standards shows good decision-making. Be the pilot-in-command and go around if it isn’t right.

Weight and balance calculations. It is amazing how many applicants tell me, and I am not joking here, that it is OK to fly over gross weight or out of CG limitations as depicted by the manufacturer. Even more applicants do not know how to calculate weight and balance for the aircraft they bring to the test. This is a basic function that every pilot needs to have down cold to pass a practical test. Flying outside of the weight and balance limitations of the aircraft is downright unsafe in addition to being a breach of regulations.

Not knowing airspace. Being able to identify airspace graphical depictions on VFR charts is required for all pilot levels. If an applicant can’t tell the difference between Class B, C, D, E, G airspaces, MOAs and restricted areas, and other depicted airspaces, an examiner cannot be confident they will be able to operate within the prescribed requirements of the airspaces. If you are unclear of what each airspace looks like, spend some more time with a chart legend and get it into your mind before you take your test.

Lacking knowledge of aircraft systems. Tests will cover how systems on the aircraft operate. An examiner doesn’t expect you to be an aeronautical engineer or a mechanic who can fix the aircraft when it breaks, but they will expect you to know how the fuel system operates and how you will manage it, the effects of failures of alternator or battery systems, what to do in the event of a flaps system failure, and other systems considerations.

Not being able to determine if the aircraft is airworthy. Many applicants cannot demonstrate an ability to find all required inspections have been completed. In many cases, they have never looked at the aircraft logbooks before the day of the test. Beyond this, even more applicants have difficulty when questioned about AD’s, how to find AD’s, and which ones might be applicable to the aircraft they brought, or what to do if something in the aircraft is not working properly. Further required on some tests is an understanding of what would be required to obtain a special flight permit.


Jason Blair is an active single and multi-engine instructor and FAA Designated Pilot Examiner with 4,800 hours total time and 2,700 hours instruction given. He has served on several FAA/Industry aviation committees and has and continues to work with aviation associations on flight training issues. He also consults on aviation training and regulatory efforts for the general aviation industry.

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