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Regulations: Notices to Airmen

Today, we’ll take a look at NOTAM’s with an excerpt from Bob Gardner’s textbook The Complete Private Pilot (PPT-12). For all of the regulations pertaining to aviation, check out our annual FAR/AIM series.

Information that might affect the safety of a flight, such as a runway closure, Temporary Flight Restriction (TFR), NAVAID outage, lighting system change, etc., is available from your flight service station briefer.

Your briefer has access to NOTAMs. So do you, at PilotWeb. If you use one of the computer flight planning products such as DUATS or the AOPA flight planner, you will also receive current NOTAMS—but be aware that TFRs can pop up without warning. Always check for them with flight service before takeoff to avoid being intercepted by F-16s or Coast Guard helicopters and forced to land.

If you want to know about VOR outages, runway closures, men and equipment on the runway, etc., look for or ask for D NOTAMs. For long cross-countries it is always valuable to call one of the fixed-base operators at the destination airport for last-minute information, such as “the power is out and we can’t pump gas!”

To make it easier for pilots to scan through a list of NOTAMs for information specific to their flight, the FAA uses “key words” in the first line of text. See the figure below—although this FAA document does not include recent additions: ODP, SID, STAR, CHART, DATA, IAP, VFP, ROUTE, SPECIAL, or (O); also, the keyword RAMP will no longer be used. As a VFR pilot, you are definitely interested in Visual Flight Procedure (VFP) and Obstacle Departure Procedure (ODP) NOTAMs which, although intended for instrument pilots, might contain information useful to you.

Every 28 days the FAA releases the Notices to Airmen publication that contains all current NOTAM (D)s and FDC NOTAMs, except for Temporary Flight Restrictions. When a NOTAM is published here (or in the Chart Supplements U.S.) it no longer shows up on the briefer’s screen; if you don’t ask the briefer for any published NOTAMs that will affect your flight, you will never find out about them. You can get this publication online at


Example of FAA NOTAM “key words” (see AIM Table 5-1-1 for more keywords and definitions). (Click to expand)

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Human Factors: Optical Illusions

Of the senses, vision is the most important for safe flight. However, various terrain features and atmospheric conditions can create optical illusions. These illusions are primarily associated with landing. Since pilots must transition from reliance on instruments to visual cues outside the flight deck for landing at the end of an instrument approach, it is imperative that they be aware of the potential problems associated with these illusions and take appropriate corrective action. Today, we’ll take a look at the major illusions leading to landing errors with an excerpt from the Pilot’s Handbook of Aeronautical Knowledge.

Runway Width Illusion
A narrower-than-usual runway can create an illusion that the aircraft is at a higher altitude than it actually is, especially when runway length-to-width relationships are comparable. The pilot who does not recognize this illusion will fly a lower approach, with the risk of striking objects along the approach path or landing short. A wider-thanusual runway can have the opposite effect with the risk of the pilot leveling out the aircraft high and landing hard or overshooting the runway.

Runway and Terrain Slopes Illusion
An upsloping runway, upsloping terrain, or both can create an illusion that the aircraft is at a higher altitude than it actually is. The pilot who does not recognize this illusion will fly a lower approach. Downsloping runways and downsloping approach terrain can have the opposite effect.


(Click to expand)

Featureless Terrain Illusion
An absence of surrounding ground features, as in an overwater approach over darkened areas or terrain made featureless by snow, can create an illusion that the aircraft is at a higher altitude than it actually is. This illusion, sometimes referred to as the “black hole approach,” causes pilots to fly a lower approach than is desired.

Water Refraction
Rain on the windscreen can create an illusion of being at a higher altitude due to the horizon appearing lower than it is. This can result in the pilot flying a lower approach.

Atmospheric haze can create an illusion of being at a greater distance and height from the runway. As a result, the pilot has a tendency to be low on the approach. Conversely, extremely clear air (clear bright conditions of a high attitude airport) can give the pilot the illusion of being closer than he or she actually is, resulting in a high approach that may result in an overshoot or go around. The diffusion of light due to water particles on the windshield can adversely affect depth perception. The lights and terrain features normally used to gauge height during landing become less effective for the pilot.

Flying into fog can create an illusion of pitching up. Pilots who do not recognize this illusion often steepen the approach abruptly.

Ground Lighting Illusions
Lights along a straight path, such as a road or lights on moving trains, can be mistaken for runway and approach lights. Bright runway and approach lighting systems, especially where few lights illuminate the surrounding terrain, may create the illusion of less distance to the runway. The pilot who does not recognize this illusion will often fly a higher approach.

How To Prevent Landing Errors Due to Optical Illusions
To prevent these illusions and their potentially hazardous consequences, pilots can:

  1. Anticipate the possibility of visual illusions during approaches to unfamiliar airports, particularly at night or in adverse weather conditions. Consult airport diagrams and the Chart Supplement U.S. (formerly Airport/Facility Directory) for information on runway slope, terrain, and lighting.
  2. Make frequent reference to the altimeter, especially during all approaches, day and night.
  3. If possible, conduct an aerial visual inspection of unfamiliar airports before landing.
  4. Use Visual Approach Slope Indicator (VASI) or Precision Approach Path Indicator (PAPI) systems for a visual reference, or an electronic glideslope, whenever they are available.
  5. Utilize the visual descent point (VDP) found on many nonprecision instrument approach procedure charts.
  6. Recognize that the chances of being involved in an approach accident increase when an emergency or other activity distracts from usual procedures.
  7. Maintain optimum proficiency in landing procedures.

In addition to the sensory illusions due to misleading inputs to the vestibular system, a pilot may also encounter various visual illusions during flight. Illusions rank among the most common factors cited as contributing to fatal aviation accidents. Sloping cloud formations, an obscured horizon, a dark scene spread with ground lights and stars, and certain geometric patterns of ground light can create illusions of not being aligned correctly with the actual horizon. Various surface features and atmospheric conditions encountered in landing can create illusions of being on the wrong approach path. Landing errors due to these illusions can be prevented by anticipating them during approaches, inspecting unfamiliar airports before landing, using electronic glideslope or VASI systems when available, and maintaining proficiency in landing procedures.

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We’re here at EAA Airventure Oshkosh 2017!

We’re here! Come find us at our booth (2075-2079) in Hangar B, showcasing our current line of training products and pilot supplies along with some new products. Come say hello and get your flight training questions answered by ASA staff.


On Monday, July 24th (tonight!), ASA will be hosting the Collegiate Tailgate Party in Aviation Gateway Park from 5:00-6:30 PM. We had a great time hanging out last year and are looking forward to doing it again. There will be food, music, games, and prizes, so come on out and join us!


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Procedures and Airport Operations: Crosswind Takeoff

Since The Pilot’s Manual: Flight School (PM-1C) is now available in eBook format (from ASA and iTunes), this week we’ll feature another maneuver from the textbook. The fifth edition of Flight School covers everything you need to know in order to fly your airplane through the maneuvers required for certification.

Not all airports have a runway that faces upwind on a given day. For this reason, takeoffs and landings on runways where there is a crosswind component are frequent events. Every airplane type (from the smallest trainer up to the Airbus A340 and Boeing 747) has a maximum crosswind component specified in the flight manual and pilot’s operating handbook. If the actual crosswind component on the runway exceeds the limit for the airplane or what you feel is your own personal limit, then use a different runway (which may even mean proceeding to a different airport).

Takeoff Run
A crosswind blowing under the upwind wing will tend to lift it. Counteract this effect and keep the wings level with aileron; that is, move the control column upwind. While full deflection might be required early in the takeoff run, this can be reduced as the faster airflow increases control effectiveness. You do not have to consciously think of aileron movement; just concentrate on keeping the wings level.

A right crosswind, for example, requires right control column and left rudder (crossed controls). A glance at the wind sock before you open the throttle for the takeoff run will allow you to anticipate this and position the controls correctly.

As speed increases, the amount of aileron and rudder required will reduce until, at liftoff, there will probably be some rudder still applied, but little or no aileron. There is no need to consciously think about this; just:

  • keep straight with rudder; and
  • keep the wings level with the ailerons.

Allow the aircraft to accelerate. Use as much rudder as necessary but avoid braking. In a crosswind takeoff, hold the airplane on the ground during the ground run (with slight forward pressure on the control column) and then lift off cleanly and positively. It may be advisable to delay liftoff until 5 knots or so past the normal rotation speed to achieve a clean (no skip) liftoff.

Drift After Takeoff
As the airplane enters the air mass after liftoff, it will tend to move sideways with it. Any tendency to sink back onto the ground should be resisted to avoid the strong sideways forces that would occur on the landing gear.

Once well clear of the ground, the aircraft will naturally yaw upwind (weathervane) to counteract the drift. Keep the wings level. Any remaining crossed controls are removed once airborne by centralizing the balance ball and keeping the wings level. Climb out normally on the extended centerline of the runway.


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Aircraft Systems: Types of Electricity

Today, we’re featuring an excerpt from our new textbook Practical Electricity for Aviation Maintenance Technicians. As you can tell from the title, this book is geared for new AMT candidates, but it does feature a wealth of information on aircraft electrical systems useful to anyone flying or fixing airplanes.

There are two basic types of electricity: static and current. In static electricity, electrons accumulate on a surface and remain here until they build up a pressure high enough to force their way to another surface or device which has fewer electrons. Static electricity is generally a bother, and steps must be taken to prevent its formation and/or to get rid of it.

Current electricity, on the other hand, is the type most often used. There are two types of current electricity, Direct Current (DC), in which the electrons always flow in the same direction, and Alternating Current (AC), in which the electrons periodically reverse their direction of flow.

Static Electricity
When you slide across the plastic seat covers of an automobile, the friction between your clothing and the seat covers causes your clothes to pick up an excess of electrons from the seat. This is exactly the same thing described earlier when a piece of amber was rubbed with sheep’s wool.

If there is no conductor between your body and the car to make a path for these electrons to leak off, your body holds the extra electrons and is said to be charged because there is an electrically unbalanced condition between it and the car. But as soon as you touch or even come close to a bare metal part of the car, the extra electrons leave and jump to the metal in the form of a spark. This accumulation and holding of electrical charges is called static electricity.

Lightning is just a big spark. Friction of the air moving up and down inside the clouds causes water droplets in the clouds to become charged, and when enough electrons have concentrated in a cloud, the electrical pressure they produce forces them to move through the air. These electrons jump between clouds having different charges or from a cloud to the ground. This is the gigantic spark we call lightning.

As mentioned earlier, an object with an excess of electrons is negatively charged, and an object which has lost its electrons and wants to get them back is positively charged. Two positively charged or two negatively charged objects repel each other, while objects having opposite charges attract. When oppositely charged objects touch, the extra electrons travel from the negative object to the one with the positive charge and they become discharged, or electrically neutral. While static electricity has some uses, it is most often thought of as a nuisance. So a path must be provided to allow the electrons to pass harmlessly from one charged object to another before the charges can build up enough pressure to cause a spark to jump.

In addition to producing a mild shock when you touch the metal part of your car, static electricity can cause radio interference and can damage sensitive electronic components. It is possible, on a dry day, that just taking a few steps on a nylon carpet can build up more than 10,000 volts of static electricity on your body. When you have accumulated this much charge and touch some electronic components, they can be destroyed. When working with sensitive electronic equipment, always wear a grounded wrist strap to bleed off any charge on your body before handling the equipment.

Many airplanes have static discharge points or wicks installed on the trailing edges of the control surfaces. These devices allow the static charges that build up on the control surfaces as air flows over them to discharge harmlessly into the air and not cause static interference in the radio equipment.

Static discharge points are installed on the trailing edge of control surfaces to bleed off the static charges that build up as air flows over the surfaces.

Static discharge points are installed on the trailing edge of control surfaces to bleed off the static charges that build up as air flows over the surfaces.

Static electricity causes a serious fire hazard when aircraft are being fueled or defueled. The flow of gasoline or turbine fuel in the hose produces enough static electricity to cause a spark to jump and ignite explosive fumes.

Current Electricity
Current electricity is the form of electricity that has the most practical applications. A source of electrical energy such as a battery or alternator acts as a pump that forces electrons to flow through conductors. In this study of practical electricity, this flow is called current and because we are considering it to flow from positive to negative, it is positive current.

Aircraft must be electrically grounded before they are fueled. Bonding wires connect the aircraft and the fueling truck or pit together, and both of them are connected to the earth ground so that static charges that build up during fueling can pass harmlessly to ground.

Aircraft must be electrically grounded before they are fueled. Bonding wires connect the aircraft and the fueling truck or pit together, and both of them are connected to the earth ground so that static charges that build up during fueling can pass harmlessly to ground.

For current to flow, there must be a complete path from one terminal of the source back to the other terminal. The figure below shows a complete electrical circuit. The battery is the component in which chemical energy is changed into electrical energy, and current is forced out of the positive terminal, through the switch, the control device, to the lamp. The lamp acts as the load, which changes electrical energy into heat and light. The current then returns to the negative terminal of the battery. Current flows as long as the switch is closed, forming a complete path.

The electrical pressure that forces current through the circuit is measured in volts, with the basic unit of electrical pressure being one volt. Electrical current is measured in amperes or, as we more commonly call it, in amps. One amp is the flow of one coulomb per second, and one coulomb is 6.28 billion billion (6.28 x 1018) electrons. All conductors have some resistance which opposes the flow of electrons in much the same way that friction opposes mechanical movement. The basic unit of electrical resistance is the ohm. One volt of electrical pressure will force 1 amp of current to flow through 1 ohm of resistance.

This is a complete electrical circuit. When the switch is closed, current flows from the positive terminal of the battery through the lamp, where there is enough opposition that the filament gets white hot. After all of the pressure from the battery is dissipated by the lamp, the current returns to the negative terminal of the battery.

This is a complete electrical circuit. When the switch is closed, current flows from the positive terminal of the battery through the lamp, where there is enough opposition that the filament gets white hot. After all of the pressure from the battery is dissipated by the lamp, the current returns to the negative terminal of the battery.

When current flows through a resistor, power is dissipated and voltage is dropped. The voltage across a resistor can be measured with a voltmeter in the same way as the voltage produced by a battery. This voltage is caused by current (I) flowing through the resistor (R), and it is called an IR drop, or a voltage drop. The end of the resistor where the positive current enters is the positive end, and the end where it leaves is the negative end.

A battery is a source of electrical pressure that is also called an EMF, electromotive force, potential, or potential difference. All are measured in volts, and all mean essentially the same thing.

A battery is a source of electrical pressure that is also called an EMF, electromotive force, potential, or potential difference. All are measured in volts, and all mean essentially the same thing.

When current flows through a resistance, power is used, or dissipated, and voltage is dropped. The voltage dropped across a resistor can be measured with a voltmeter in the same way as the voltage produced across the terminals of a battery.

Electrical pressure caused by changing some other form of energy into electrical energy may be called an electromotive force (EMF) a potential difference, or just a potential. Electrical pressure caused by current flowing through a resistance is not a source of electrical energy; it is a drop in the electrical pressure. This voltage is usually called a voltage drop or an IR drop because the amount of drop may be found by multiplying the current (I) by the resistance (R) through which it flows. These terms for voltage are often used interchangeably, and all of them use the volt as the basic unit of measurement.

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Ground School: Preflight Inspection

The success of a flight depends largely on thorough preparation. In the course of your training, a pattern of regular preflight actions should be developed to ensure that this is the case. This includes planning the flight, and checking the airplane. These preflight actions must be based on the checks found in the pilot’s operating handbook (POH), manufacturer’s information manual or the FAA-approved airplane flight manual (AFM) for your airplane. Today we’ll share an excerpt from The Pilot’s Manual: Flight School (PM-1C) regarding the preflight inspection of your airplane.

Preparing the Airplane
The information manual for your airplane will contain a list of items that must be checked during:

  • the preflight inspection (external and internal);
  • the preflight cockpit checks;
  • the engine power check; and
  • the before-takeoff check.

At first, these checks may seem long and complicated, but as you repeat them thoroughly prior to each flight, a pattern will soon form. It is vital that the checks are carried out thoroughly, systematically and strictly in accordance with the manufacturer’s recommended procedure. Use of written checklists, if performed correctly, will ensure that no vital item has been missed, but some pilots prefer to memorize checks. The comments that follow are only general comments that will apply to most airplanes.

The External Inspection
Always perform a thorough external inspection. This can begin as you walk up to the airplane and should include:

  • the position of the airplane being safe for start-up and taxi (note also the wind direction and the likely path to the takeoff point); and
  • the availability of fire extinguishers and emergency equipment in case of fire on start-up (a rare event, but it does happen).

Some of the vital items are:

  • all switches off (master switch for electronics, magneto switch for engine) as a protection against the engine inadvertently starting when the propeller is moved;
  • fuel check for quantity and quality (drain into a clear cup);
  • oil check; and
  • structural check.

A list of typical walkaround items is shown below. Each item must be inspected individually, but do not neglect a general overview of the airplane. Be vigilant for things such as buckling of the fuselage skin or popped rivets since these could indicate internal structural damage from a previous flight. Leaking oil, fuel forming puddles on the ground, or hydraulic fluid leaks from around the brake lines also deserve further investigation. With experience, you will develop a feel for what looks right and what does not. The walkaround inspection starts at the cockpit door and follows the pattern specified in the checklist provided by the aircraft manufacturer.

  • Parking brake on.
  • Magneto switches off.
  • Landing gear lever (if retractable) locked down.
  • Control locks removed.
  • Master switch on (to supply electrical power).
  • Fuel quantity gauges checked for sufficient fuel for the planned flight.
  • Fuel selector valves on.
  • Flaps checked for operation; leave them extended for external inspection.
  • Stall warning (if electrical) checked for proper operation.
  • Rotating beacon (and other lights) checked, then off.
  • Master switch off.
  • Primary flight controls checked for proper operation.
  • Required documents on board: MAROW plus airman certificate and medical certificate for the pilot. (Note: under some circumstances a medical certificate may not be required.)
  • Cabin door securely attached, and latches working correctly.
  • Windshield clean (use correct cloth and cleanser).


  • All surfaces, the wing tip, leading and trailing edge checked for no damage or contamination; remove any frost, snow, ice or insects (on upper leading edge especially, since contamination here can significantly reduce lift, even to the point where the airplane may not become airborne).
  • Wing tip position light checked for no damage.
  • Flaps firmly in position and actuating mechanism firmly connected and safety-wired.
  • Aileron locks removed, hinges checked, correct movement (one up, the other down) and linkages safety-wired, mass balance weight secure.
  • Pitot tube cover removed and no damage or obstructions to tube (otherwise airspeed indicator will not respond).
  • Fuel contents checked in tanks and matching fuel quantity gauge indications; fuel caps replaced firmly and with a good seal (to avoid fuel siphoning away in flight into the low-pressure area above the wing).
  • Fuel sample drained from wing tanks and from fuel strainer into a clear container. Check for correct color (blue for 100LL, green for 100-octane), correct fuel grade, correct smell (aviation gasoline and not jet fuel or kerosene), no water (being denser, water sinks to bottom), sediment, dirt or other contaminant (condensation may occur in the tanks overnight causing water to collect in the bottom of the tanks, or the fuel taken on board may be contaminated).
  • Fuel port, or fuel vent (which may be separate or incorporated into the fuel cap) clear (to allow pressure equalization inside and outside the tanks when fuel is used or altitude is changed, otherwise the fuel tanks could collapse or fuel supply to the engine could stop as fuel is used).
  • Stall warning checked (if possible).
  • Inspection plates in place.
  • Wing strut checked secure at both ends.


  • All surfaces, including underneath checked for skin damage, corrosion, buckling or other damage (corrosion appears as surface pitting and etching, often with a gray powdery deposit); advise a mechanic if you suspect any of these.
  • No fuel, oil or hydraulic fluid leaking onto the ground beneath the aircraft.
  • Inspection plates in place.
  • Static ports (also called static vents)—no obstructions (needed for correct operation of airspeed indicator, altimeter and vertical speed indicator).
  • Antennas checked for security and no loose wires.
  • Baggage lockers—check baggage, cargo and equipment secure, and baggage compartments locked.

Main Landing Gear

  • Tires checked for wear, cuts, condition of tread, proper inflation, and security of wheel and brake disk.
  • Wheel oleo strut checked for damage, proper inflation, and cleanliness.
  • Hydraulic lines to brakes checked for damage, leaks and attachment.
  • Gear attachment to the fuselage—check attachment, and be sure there is no damage to the fuselage (buckling of skin, popped rivets).

Nose Section

  • Fuselage checked for skin buckling or popped rivets.
  • Windshield clean.
  • Propeller checked for damage, especially nicks along its leading edge, cracks and security (and for leaks in the hub area if it is a constantspeed propeller).
  • Propeller spinner checked for damage, cracks and security.
  • Engine air intake and filter checked for damage and cleanliness (no bird nests or oily rags).
  • Nose wheel tire checked for wear, cuts, condition of tread, proper inflation, and security of nose wheel.
  • Nose wheel oleo strut checked for damage, proper inflation (four to six inches is typical), security of shimmy damper and other mechanisms.
  • Open engine inspection panel; check engine mounts, engine, and exhaust manifold for cracks and security (to ensure that no lethal carbon monoxide in the exhaust gases can enter the cockpit—exhaust leaks may be indicated by white stains near the cylinder head, the exhaust shroud or exhaust pipes).
  • Check battery, wiring and electrical cables for security (firmly attached at both ends).
  • Check the oil level; top up if necessary (know the correct type and grade of oil to order); ensure that the dipstick is replaced properly and the oil cap is firmly closed to avoid loss of oil in flight.
  • Close the inspection panel and check its security.

Other Side of Airplane
Repeat as appropriate.


  • Remove control locks if fitted.
  • All surfaces checked for skin damage (vertical stabilizer and rudder, horizontal stabilizer, elevator and trim tab); remove any contamination such as ice, frost or snow.
  • Control surface hinges checked for cracks, firmness of attachment, safety-wiring and correct movement.

Chocks and Tiedown Ropes
Chocks and tiedowns removed and stowed (after checking the parking brake is on).

Overall View
Stand back and check the overall appearance of the airplane. It cannot be emphasized too greatly just how important this preflight inspection by the pilot is. Even if you have no experience in mechanical things, you must train yourself to look at the airplane and notice things that do not seem right. Bring any items that you are unsure of to the attention of your flight instructor or a mechanic. At this stage, you are now ready to seat yourself in the airplane and begin the internal cockpit inspection.

The Cockpit Inspection
Always perform a thorough cockpit inspection. The cockpit inspection involves preparing the cockpit and your personal equipment for flight. It should include:

  • Parking brake set (on).
  • Required documents on board (MAROW items).
  • Flight equipment organized and arranged in an efficient manner so they are readily available in flight (flight bag, charts prefolded to show your route, computer, pencils, flashlight, and so on).
  • Fuel on.
  • Seat position and harness comfortable and secure, with the seat definitely locked in position and rudder pedals (if adjustable) adjusted and locked into position so that full movement is possible.
  • Ignition switch (magnetos) off (so that the engine is not live).
  • Master switch on (for electrical services such as fuel gauges).
  • Flight controls checked for full and free movement (elevator, ailerons, rudder and trim wheel or handle). Trim set to takeoff position.
  • Engine controls checked for full and free movement (throttle, mixture control and carburetor heat).
  • Scan the instruments systematically from one side of the panel to the other for serviceability and correct readings.
  • No circuit breakers should be popped nor fuses blown (for electrical services to operate).
  • Microphone and/or headsets plugged in (if you are to use the radio) and test intercom if used.
  • Safety equipment (fire extinguisher, first aid kit, supplemental oxygen if planning to fly high, flotation equipment for overwater flights) on board and securely stowed.
  • Loose articles stowed.
  • Checklists on board and available.
  • Read the preflight checklist, if appropriate.

Normal checklists are found in Section 4 of the typical pilot’s operating handbook, and emergency checklists are found in Section 3. Written checklists are used to confirm that appropriate procedures have been carried out, for example, the before-takeoff checklist or the engine fire checklist. In earlier days, when airplanes were simpler, checks were usually memorized. Nowadays, in more complex airplanes and in a much busier operating environment, many checks are performed with the use of standard written checklists for that airplane. Checklists are usually compiled in a concise and abbreviated form as item and condition (for example, fuel—on), where the item to be checked is listed, followed by a statement of its desired condition. Explanations for actions are usually not included in the concise checklist, but may generally be found in the pilot’s operating handbook if required.

Vital checklists are best committed to memory so that they may be done quickly and efficiently, followed by confirmation using the printed checklist if required. Emergency checklists, such as the engine fire checklist, often have some items that should be memorized, since they may have to be actioned immediately, before there is time to locate the appropriate checklist and read it. These items are often referred to as memory items or phase-one items, and are often distinguished on checklists by bold type or by being surrounded with a box. The method of using checklists may be one of:

  • carrying out the items as the checklist is read; or
  • carrying out the items in full, followed by confirmation using the checklist.

Be sure to check back Thursday for more on preflight from our CFI as well as something interesting from SunState Aviation!

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Procedures and Airport Operations: Runway Incursions

Learn to reduce your risk of a runway incursion by following these simple FAA recommendations outlined in the Instrument Procedures Handbook (FAA-8083-16A).

On any given day, the NAS may handle almost 200,000 takeoffs and landings. Due to the complex nature of the airport environment and the intricacies of the network of people that make it operate efficiently, the FAA is constantly looking to maintain the high standard of safety that exists at airports today. Runway safety is one of its top priorities.

The FAA defines a runway incursion as:
“Any occurrence at an aerodrome involving the incorrect presence of an aircraft, vehicle, or person on the protected area of a surface designated for the landing and takeoff of aircraft.”

The four categories of runway incursions are listed below:
Category A—a serious incident in which a collision was narrowly avoided.
Category B—an incident in which separation decreases and there is a significant potential for collision that may result in a time critical corrective/evasive response to avoid a collision.
Category C—an incident characterized by ample time and/or distance to avoid a collision.
Category D—an incident that meets the definition of runway incursion, such as incorrect presence of a single vehicle/person/aircraft on the protected area of a surface designated for the landing and takeoff of aircraft but with no immediate safety consequences.

The below figure highlights several steps that reduce the chances of being involved in a runway incursion.

Fig 1-5


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Aerodynamics: Power

Today’s post is excerpted from the second edition of our textbook Aerodynamics for Aviators. This book features extensive illustrations and covers everything from the fundamentals of flight to high-speed flight, and includes an excellent compendium of formulae and equations used at all levels of aviation.

Aircraft aerodynamics involves the interaction of the four forces: lift, weight, thrust, and drag. The first basic issue to understand is the difference between propeller-driven aircraft power and jet engine thrust. Power is what a propeller-driven engine produces; thrust is what a jet engine produces. In a propeller-driven aircraft, the propeller—not the engine—is said to produce thrust. The thrust on a propeller-driven aircraft decreases with an increase in velocity; in a jet aircraft, thrust remains relatively constant with an increase in aircraft velocity.

(A) Thrust vs. velocity, jet engine; (B) Thrust vs. velocity, propeller-driven engine.

(A) Thrust vs. velocity, jet engine; (B) Thrust vs. velocity, propeller-driven engine.

Therefore, the power required curve versus the power available curve for a propeller driven aircraft and a jet aircraft will look different.

Power required versus power available (A) for a jet engine and (B) for a propeller-driven aircraft.

Power required versus power available (A) for a
jet engine and (B) for a propeller-driven aircraft.

Propeller Efficiency
Propeller efficiency is a measure of how much power is absorbed (transmitted) by the propeller and turned into thrust. In order to understand propeller efficiency, it’s helpful to start with a basic review of propeller principles. Propellers on aircraft consist of two or more blades and a hub. The blades are attached to the hub, and the hub is attached to the crankshaft on a piston-powered aircraft and to a gear reduction box on most turbo-prop aircraft. The propeller is simply a rotating wing that produces lift along the vertical axis. We call this lift force thrust.

Forces in flight.

Forces in flight.

Looking at a cross section of the propeller blade, we can see that it is similar to a cross section of an aircraft wing. The top portion of the blade is cambered like the top surface of a wing. The bottom portion is flat like the bottom surface of a wing.

Propeller cross section.

Propeller cross section.

The chord line is an imaginary line drawn from the leading edge of the propeller blade to the trailing edge of the propeller blade. Blade angle, measured in degrees, is the angle between the chord of the blade and the plane of rotation. The pitch of the propeller is usually designated in inches. A “78-52” propeller is 78 inches in length with an effective pitch of 52 inches. The effective pitch is the distance a propeller would move through the air in one revolution if there were no slippage. On a “78-52” propeller this distance would be 52 inches.

Propeller blade angle.

Propeller blade angle.

There are two types of propellers that can be installed on most general aviation aircraft: a fixed-pitch propeller or a controllable-pitch propeller. The fixed-pitch propeller is at the blade angle that will give it the best overall efficiency for the type of operation being conducted and for which the aircraft was designed. For most aircraft this would be a cruise setting. A controllable-pitch propeller allows the pilot to adjust the blade angle for the different phases of flight. On takeoff and climb out, a low pitch/high RPM setting is used. During cruise flight a high pitch/low RPM setting is generally used.

On the ground with the aircraft in a static condition, the propeller efficiency is very low because each blade is moving through the air at an angle of attack that produces a very low thrust to power ratio. This means that a lot of power is being used to sustain the engine and rotate the propeller while very little thrust is being produced. The propeller, unlike the wing, moves both rotationally and forward (dynamically). The angle at which the relative wind strikes the propeller blade is the AOA. This produces a higher dynamic pressure on the engine side, which in turn is called thrust. Thus thrust is the relationship of propeller AOA and blade angle.

Propeller blade angle with forward velocity.

Propeller blade angle with forward velocity.

Since an aircraft moves forward through the air, it is important that the pilot understands how forward velocity affects the AOA of the propeller. The figure above shows the propeller in a static condition on the ground. At this point the relative wind is opposing propeller rotation. As forward velocity increases, the relative wind moves closer to the chord line, decreasing the propeller AOA. This can easily be demonstrated in an aircraft with a fixed-pitch propeller by pitching up or down without changing power. When the aircraft is pitched down, RPM will increase as the relative wind moves closer to the chord line and the AOA is decreased. When the aircraft is pitched up, the RPM will decrease as the relative wind moves farther from the chord line and the AOA is increased.

Propeller efficiency is a ratio between thrust horsepower and brake horsepower. Brake horsepower (BHP) is the horsepower actually delivered to the output shaft. Brake horsepower is the actual usable horsepower. Thrust horsepower (THP) is the power that is imparted by the propeller to the air. Propeller efficiency is the relationship between brake horsepower and thrust horsepower. If the BHP of the engine is 200, the THP is less (20–40%). Some power is lost to turn the engine and propeller. Propeller efficiency usually varies between 50 and 80% on light general aviation aircraft.

The measure of efficiency is how much a propeller slips in the air. This is measured by the geometric pitch (theoretical) which shows a propeller with no slippage. Effective pitch is the distance that the propeller actually travels.

Propeller efficiency.

Propeller efficiency.

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Procedures and Airport Operations: Normal Landing

A good landing is most likely following a good approach, so aim to be well established in a stabilized approach with the airplane nicely trimmed by the time you reach short final, the last part of the approach. Short final for a training airplane may be thought of as the last 200 feet.

The landing starts with a flare commencing when the pilot’s eyes are about 15 feet above the runway. The pilot uses texture, height of peripheral objects, width of the runway and the perceived height of the horizon as cues to commence the flare and to judge the rate of rotation to achieve an almost level path over the runway. The landing is not complete until the end of the landing roll.

Once you reach the flaring height, forget the aim point because you will fly over and well past it before the wheels actually touch down. It has served its purpose and you should now look well ahead. Pick a point at the center of the far end of the runway. Transfer your visual attention to this point and slowly retard the throttle.

A normal landing is similar to the approach to the stall, with attitude being increased to keep the aircraft flying at the reducing airspeed. Touchdown will occur just prior to the moment of stall. Do not rush and try not to be tense. The aircraft will land when it is ready. This method of landing allows the lowest possible touchdown speed (significantly less than the approach speed), with the pilot still having full control.

The landing consists of four phases:

  • flare (or round-out);
  • hold-off;
  • touchdown; and
  • landing roll.

During the flare (round-out) the power is reduced and the nose is gradually raised to reduce the rate of descent. A small rate of sink is checked by a slight attitude change, a high rate of sink requiring a greater and quicker backward movement. A greater descent rate may require the pilot to add power momentarily to arrest the descent.

The hold-off should occur with the airplane close to the ground (with the wheels within a foot or so). The throttle is closed and the control column progressively brought back to keep the airplane flying a level path with the wheels just off the ground. If sinking, apply more back pressure; if moving away from the ground, relax the back pressure. The airspeed will be decreasing to a very low figure, but this is of no concern to you. You should be looking well ahead from the beginning of round-out until touchdown. Any sideways drift caused by a slight crosswind can be counteracted by lowering the upwind wing a few degrees and keeping straight with rudder.

On touchdown, the main wheels should make first contact with the ground (which will be the case following a correct hold-off ). The nose wheel will want to drop immediately but should be kept off the ground using the control column while the speed decreases. This may require a significant rearward pressure to allow it to touch gently.

Landing Roll
During the landing roll the airplane is kept straight down the centerline using rudder and the wings kept level with aileron. Look at the far end of the runway. The nose wheel is gently lowered to the ground before elevator control is lost. Brakes (if required) may be used once the nose wheel is on the ground. Remember that the landing is not complete until the end of the landing roll when the airplane is stationary or has exited the runway at taxiing speed.

For more on landing technique, and every maneuver required for certification, check out the brand new fifth edition of ThePilot’s Manual: Flight School (PM-1C).

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Regulations: First Solo Flight

You are able to fly solo when the instructor believes, with some confidence, that you can fly safely with a degree of consistency and you have mastered the presolo maneuvers defined in the regulations. Most important is evidence that you are taking control and responsibility for your own actions—that you are walking on your own two feet. Today’s post comes from the new fifth edition of The Pilot’s Manual: Flight School (PM-1C).

The instructor is looking to see you make corrections for inaccuracies without waiting to be told and without asking for instructions, responding to radio calls without question and saying what you intend to do rather than asking what is next. These are the signs of aviation maturity, of being in command. They are no different from other life skills, just applied at a higher altitude.

First solo is an unforgettable experience that you will remember and treasure all your life. When your instructor tells you to stop after turning off the runway, steps out of the airplane, secures the harness and then leaves you to your first solo flight, you are being paid a big compliment. Your instructor is confident that you can safely complete a solo traffic pattern. You have demonstrated sufficient awareness, skill and consistency to be trusted to take the aircraft up by yourself.

You may feel a little apprehensive (or very confident), but remember that the instructor is trained to judge the right moment to send you solo. Your instructor has a better appreciation of your flying ability than anybody (including you—especially you).

Your instructor will have observed your progress and have assessed your consistency, safety and predictability. It is not the occasional brilliant landing that is looked for, but a series of consistently safe ones. Your instructor will choose the conditions and the traffic so that they are not more demanding than you are used to.

You know instinctively when you are ready to fly solo. In some cases, you may feel you are ready before time. Your instructor knows when the time is right. Trust in that.

Your instructor will also advise the control tower that this is a first solo and the controller will keep a watchful eye open for this new fledgling. The controller will anticipate wind changes and try not to change the active runway while you are flying your first solo traffic pattern.

Presolo Written Exam
Before going solo, you must have passed a written examination administered and graded by the flight instructor who endorses your logbook for solo flight. The written examination will include questions on the applicable Federal Aviation Regulations, and the flight characteristics and operational limits of your airplane. By answering the review questions of each exercise during your training, you will be well prepared for the questions on the flight characteristics and operational limits of your airplane.

These next review questions prepare you for the regulations questions. They direct you into your current copy of the regulations to indicate the level of knowledge you require prior to going solo. Since regulation numbering changes from time to time, the part has been identified—for example, Part 91 and Part 61—but not the individual section, which you can easily find using the table of contents page in your book of regulations.

Fly your first solo traffic pattern in the same manner as you flew the pattern before the instructor stepped out. The usual standards apply to the takeoff, pattern and landing. Follow exactly the same pattern and procedures. Maintain a good lookout, fly a neat pattern, establish a stabilized approach and carry out a normal landing. Be prepared for better performance of the airplane without the weight of your instructor on board. If at any stage you feel uncomfortable, go around. Many students comment on how much better the airplane flies without an instructor and how much quieter it is!

Be in control. Do not be blown with the wind. The tower will try to avoid any interruptions or runway changes while you are airborne but, if there is a need for you to hold overhead the field or to change runway, then take your time, think through the best plan of action, ask for instructions if you are in doubt and then complete a normal pattern and landing.

If an emergency occurs, such as engine failure (and this is an extremely unlikely event), carry out the appropriate emergency procedure that you have been taught. If your radio fails simply complete the pattern and land normally. Be aware of other traffic. You have been taught to go around and it may happen even on your first solo. Simply complete another pattern.

Your flight instructor, when sending you solo, not only considers you competent to fly a pattern with a normal takeoff and landing, but also considers you competent to handle an abnormal situation. One takeoff, one pattern and one landing are the rites of passage to the international community of pilots.

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