Basic airplane components; fuselage, wings, empennage, landing gear, powerplant
Flight controls;
3 primary flight controls; ailerons, elevator, rudder
ailerons; located on the back end of the wings towards the tiptoe control the roll or bank
elevator; attached to the back end of the horizontal stabilizer to control the pitch to climb or descend
rudder; attached to the back end of the vertical stabilizer to create yaw
2 secondary flight controls; flaps, trim
Powerplant and Propeller;
reciprocating engines with cylinders; fuel and air are mixed, compressed, and ignited. As it ignites, the piston moves inward. When these pistons move in and out, the crankshaft that they are connected to begins to rotate. As it begins to rotate, it is connected to the propeller and it also begins to rotate. This creates a four stroke cycle; intake, compression, power, exhaust.
throttle controls-amount of fuel and air that go into the cylinders
mixture controls-how much fuel is mixed with the air
Major components of ignition system; magnetos, spark plugs, wires, and ignition switch.
As combustion is occurring in the cylinder, the pistons are rotating the crankshaft, directly driving the propeller. Equal thrust is created along the propeller blade from being twisted.
Landing gear: provides ground support to airplane for taxi, takeoff, and landing
With a tricycle landing gear system, when the pilot pushes the rudder petals, the nose wheel rotates alowing the pilot to steer. Differential breaking can be used on a plane with a tricycle system for sharper turns.
Landing gear category classifications:
fixed - where the landing gear is permanently extended
retractable - when landing gear can fold into the bottom of the plane, benefit being that it can increase performance by streamlining the airplane
Fuel system sub-groups:
gravity fed - high wing airplanes
fuel pump - low wing airplanes (required to send fuel from the tanks to the engine since fuel is located below the engine and needs to be sent upward
If a fuel tank did not have a vent, fuel could initially flow from the tank, but as the level decreases, there would be nothing replenish it, creating a vacuum that would stop fuel flowing to the engine.
Most general aviation planes use 100-LowLead fuel, that is blue.
As the oil is cooling the engine, it lubricates the moving parts, providing a protective coating to prevent corrosion and remove dirt and other particles from the engine.
Two types of systems:
wet-sump: oil is located in a tank at the base of the engine
dry-sump: has a separate oil tank that separates the oil system from the engine.
With smaller planes, the hydraulic system powers the breaks to stop the plane, extend or terrace the landing gear, or change the blade angle on a constant speed propeller.
If the breaks are pressed on, a piston drives fluid from the break actuator on the pedal, through hydraulic lines, then to the actuator near the wheels. The fluid then pushes a piston that mechanically squeezes the break pads against the break disk, causing the plane to slow down.
The Electrical System -
The electrical system is usually a 14 or 28 volt DC (direct current) system comprised of basic components. This is made up of: an alternator, battery, switches, circuit breakers/fuses, relays, voltage regulator, ammeter/loadmeter, electrical wiring to connect it all.
The alternator is driven from the engine by an alternator belt that generates electricity for the system. A circuit breaker will pop when there is excessive voltage, causing high heat in the electrical wiring. An ammeter shows the performance of the electrical system. If the alternator is providing sufficient power to the electrical system and charging the battery, the ammeter will show a charge. A load meter will show the load that is being placed on the alternator.
The Environmental System -
The environmental system provides fresh air and heat to the cabin. The cabin heat valve allows outside air to pass over the exhaust muffler shroud, that heats the air. The heated air then is ducted into the cabin.
Four forces acting on airplane while it is in flight: lift, drag, thrust, and weight.
According to Newtons 3rd law, for every action, there is an equal and opposite reaction. In regular flight, as the air flows around the wing, the air is deflected downward as it flows around it, the wind lifts the wing up.
Bernoullis Principle also states that as the velocity of a fluid (the air) increases, its internal pressure decreases.
The lift will continue to increase until a certain angle of attack, the critical angle of attack. IE: A stall will always occur at the same angle of attack. To recover from a stall is to reduce the angle of attack below the critical angle. Power should be added to minimize the amount of altitude lost in the recovery and increase the planes speed as quickly as possible.
High lift devices, such as flaps, are designed to increase the lift and drag that are generated by the wings at low airspeeds.
Four types of flaps: each with own set of characteristics to suit their airplane
plain
split
slotted
Fowler
Weight is the force of gravity that is pulling the aircraft back to the ground. This force always acts vertically downward towards the center of the earth, regardless of the aircrafts attitude.
Thrust is the forward-acting force, opposing drag, that propels the aircraft.
A propeller is an airfoil, as such, as it rotates, its blades accelerate the surrounding air towards the aft end of the aircraft.
Parasite drag is a direct result of the air resistance as the aircraft flies through the air.
Three types of parasite drag:
form drag
interference drag
skin friction drag
The amount of parasite drag varies with the speed of the aircraft.
Induced drag comes from the wing creating lift and behind the wing being a downward wash of air. A pilot can experience reduced induced drag is by flying in ground effect. With flying with a wingspan of the ground, the ground itself changes the downwash of the air flowing over the wings. This shifts the left vector forward and reduced the amount of induced drag.
Straight-and-level when a constant heading and altitude are are maintained.
The pilots primary focus should be looking outside on the horizon. The FAA recommends that pilots keep their focus outside 90% of the time.
In normal cruise flight, when an aircraft is maintaining constant airspeed, thrust and drag are equal.
To get a plane to climb, more lift needs to be created than weight.
3 different types of climb:
best rate of climb - VY
best angle of climb - VX
type of climb used most often - cruise climb
Descents occur when the amount of lift produced is less than the weight of the aircraft.
partial power descents
descents at minimum safe airspeeds
glide - basic maneuver at which the airplane loses altitude in a controlled descent with little or no engine power.
When an airplane is in a straight-and-level attitude, 100% of the lift is used to counteract weight. When an airplane is in a bank, the lift produced follows the direction of the bank, and no longer is directed straight up. With the new attitude, there is still vertical lift that opposes weight, but the added component of horizontal lift.
The wing producing more lift also produces more drag.
Adverse yaw - If you are tying to make a left turn, the added right drag will pull the nose to the right.
To counteract adverse yaw, the pilot should press the rudder pedal in the direction of the turn to help force the nose.
The Pitot-Static System -
The pitot-system is connected to the aircrafts altimeter, airspeed indicator, and vertical speed indicator. These instruments tell the pilot how high they are, how fast they are going, and how fast they climb or descend.
The pitot-static system gathers its pressure information from the pitot tube and static port.
Altimeter -
Most basic of all pitot-static instruments is altimeter, that displays the aircraft altitude.
Types of altitude:
indicated
MSL (mean sea level)
AGL (above ground level) - the vertical distance between the aircraft and ground below [MSL minus the terrain elevation]
pressure altitude
density altitude
true altitude - similar to pressure and density altitudes, takes both pressure and temperature of the air to give a more accurate reading
Pressure and density altitudes - are theoretical altitudes used to calculate the performance of the aircraft. It's the altitude that the plane performs like it's flying at. (based on atmosphere temperature and pressure)
Vertical speed indicator: uses only information from the static port that measures the vertical speed of the aircraft in terms of feet per minute
Airspeed Indicator -
Airspeed indicator - only pitot-static instrument that uses both input from the static port and pitot tube. The face of the instrument displays various color-coded speed ranges that the pilot should be aware of why flying to avoid exceeding any limitations of the aircraft.
The green arc is for normal operations.
The white arc is when you're allowed to extend the flaps.
The yellow arc is limited to flight in smooth air only.
The red line indicates the maximum allowed speed.
Indicated airspeed: most commonly used airspeed, read directly off of the instrument
Calibrated airspeed: takes the indicated airspeed and corrects for any known installation or instrument errors
Equivalent airspeed: takes the calibrated airspeed and corrects for any potential compressibility
True airspeed: actual airspeed that you are traveling at, after all corrections are made
Mach: ratio of true airspeed to the speed of the sound.
Blockages -
The pitot-static system is subject to suffer from blockages of the pitot tube or static port from anything from ice to insects or other debris. If the pitot tube opening gets blocked, but the drain hole remains open, the airspeed indicator would read zero. If both the pitot tube and drain hole become blocked, the pressure in the pitot tube is trapped and the airspeed indicator will not change, as long as the aircraft altitude remains the same. If the static port becomes blocked, it will affect all three of the pitot static instruments, first being the airspeed indicator. If the static port gets blocked, the airspeed indicator loses its static reference so it will not be able to correctly show airspeed. When the static port is blocked, the altimeter will freeze at the altitude the blockage occurred at, and the VSI will return to 0.
Gyroscopic instruments include the attitude indicator, heading indicator, and turn coordinator.
Rigidity in space refers to a gyros ability to remain in a fixed position in the aircraft in which it is spinning.
Precession is the tilting or turning of a gyro in response to a force. A small force is applied to the gyro whenever the aircraft changes direction. Instead of the gyro responding at the source of the force, the result will occur 90 degrees ahead of that point in the direction of rotation.
Attitude indicator: instrument used to inform the pilot of the orientation or attitude of the aircraft relative to the earth. It indicates pitch, which is the force and aft tilt, and bank or roll, which is the side-to-side tilt.
Heading indicator: senses the aircrafts movement and displays heading based on a 360 degree azimuth in 5 degree increments.
Turn coordinator: a supporting instrument used while banking, to indicate both the rate and quality of turns. It can also be used as a backup source of bank information in the event that the attitude indicator fails.
Compass: self-contained instrument that doesn't require electricity or other mechanisms.
G1000 -
The G1000 setup typically consists of two display units, the Primary Flight Display, or PFD, and the Multi-Function Display, or MFD.
The PFD displays the basic flight instruments.
The MFD, on the right, is used to display a wide array of menus and features. Its main purpose is to display a navigational map of the area surrounding the plane.
Line Replaceable Units provide information and display it digitally.
Airport Layout -
When an airport is built, the runways are laid out so that the approaches to the runways avoid higher terrain and obstructions, and the primary runway is aligned as much as possible with the commonly prevailing winds; any secondary runways are for when winds are from other directions.
At towered airports, ATC and pilots communicate over a series of distinct frequencies. At non-towered airports, pilots communicate over a Common Traffic Advisory Frequency, or CTAF.
Traffic Patterns -
The basic traffic pattern is similar at all airports whether it is controlled by a control tower, or a non-towered airport. The traffic pattern consists of a rectangular shape made up of 5 different legs: departure, crosswind, downwind, base, and final. The standard traffic pattern is referred to as left traffic.
At most airports, the traffic pattern is typically flown 1000 feet above the elevation of the airport. The pilot should enter the pattern on a 45 degree angle to the downwind leg, flying towards the approach end of the runway.
Wind Indicators and Nose Abatement Procedures -
A pilot can get wind information by radio, from observers on the ground, or from automated systems, such as ASOS, or AWOS, that broadcast the information. A pilot can also use wind socks, wind tees or tetrahedrons to judge the wind direction and speed.
At some airports, the pattern procedures may be amended to minimize the over-flight of the more-noise-sensitive areas. To find if noise abatement procedures exist at an airport you can consult the A/FD or similar publications.
Runway Markings -
Each runway is identified with large white numbers painted on each end. These numbers may seem arbitrary, but in fact, they correspond with the magnetic direction they face, and if there are multiple runways with the same direction they are differentiated by the suffixes "Left", "Center", and "Right."
To mark runways that are undergoing maintenance, are currently unsafe or have been permanently closed, yellow Xs are placed on the ends.
If part of the approach end of a runway is usable for taxi and take-off, it will be marked with white arrows, signifying a displaced threshold. Runway pavement that cannot be used for taxi, take-off, or landing is marked with yellow chevrons.
Taxiways are given letter designators and taxiway markings are yellow. When a taxiway comes in contact with a runway, Runway Holding Position Markings are used. They consist of four yellow lines, two solid, and two dashed, extending across the width of the taxiway.
Airport Signage -
Mandatory Instruction Signs have a red background with white text. They are used to identify: an entrance to a runway or critical area, or an area where an aircraft is prohibited from entering.
The runway numbers on the sign are arranged to indicate which direction the beginning of each runway is. Example: "15-33" indicates that the beginning of Runway 15 is to the left, and the beginning of Runway 33 is to the right.
Location Signs are used to identify either a taxiway or runway on which the aircraft is located. This sign consists of a black background with yellow text, and a yellow border. To go along with location signs, there are direction signs. Unlike location signs, these signs have a yellow background with black text, and are accompanied with an arrow.
Similar to direction signs, destination signs look identical to direction signs, but instead instruct a pilot how to get to a certain location. These signs can indicate directions to FBOs, terminals, customs, fueling areas, and other locations.
Information signs are used to provide pilots with information on such things as applicable radio frequencies, and noise abatement procedures.
Runway Distance Remaining signs consist of white text on a black background, and are located on one or both sides of the runway to indicate the distance of runway remaining, in thousands of feet.
Airport Lighting -
Lighted civilian land airports have a rotating or flashing beacon that flashes alternately white and green. Military airports flash two whites between each green, while seaplane airports flash alternating yellow and white. Heliports flash green-yellow-white.
Runway edge lighting consists of white lights; on more sophisticated runways, yellow lights are instead used on the last 2,000 feet of the runway or half the runway length, whichever is less.
Taxiway lights are used to outline the edges of the taxiways and are blue in color. Some airports may also install taxiway centerline lights, which are green in color.
Runway Incursion Avoidance, LAHSO, and NOTAMS -
A constant look-out is first priority. Read back all taxi instructions from ground control, especially all hold-short instructions, so that ATC can confirm you understood your taxi instructions. Know where you are and where you are going. Finally, familiarize yourself with any "Hot Spots" on the airport.
To be able to use both runways simultaneously the tower may issue the light plane a "Land and Hold Short" clearance. With Land and Hold Short Operations the pilot has the right to accept or refuse the clearance (except for solo student pilots, who are prohibited from accepting Land and Hold Short clearances.
This new information is published in NOTAMs, or NOTices to AirMen. NOTAMs may include changes and temporary closures of runways and taxiways, lighting and navigation equipment outages, airport maintenance and construction and other hazards.
Categories and Types of Airspace -
There are two categories of airspace or airspace areas: Regulatory (Classes A, B, C, D, E, G, Restricted areas, and Prohibited areas) and Non-Regulatory( Military operations areas, Warning areas, Alert areas, and Controlled firing areas).
The two categories are broken into 4 types: controlled, uncontrolled, special use, and other.
Prohibited Areas exist for security or other reasons associated with national welfare, where aircraft are not permitted to fly. On Sectional Charts, this airspace is depicted with a blue hashed shape.
Restricted Areas contain the existence of unusual, often invisible, hazards to aircraft, such as artillery firing, aerial gunnery, or guided missiles. Sectional Charts depict this airspace in the same manner as prohibited areas, using a blue hashed shape However, the identifier starts with the letter R instead of P.
Warning Areas contain activity that may be hazardous to nonparticipating aircraft. They exist to warn nonparticipating pilots of potential danger, but do not prevent or limit other aircraft from operating within that area.
Military Operating Areas, or MOAs, contain activities such as air combat tactics, air intercepts, aerobatics, formation flying, and low-altitude tactics. Whether or not an MOA is in use, VFR traffic may still fly through the area. However, extreme caution should be used when flying through an active MOA. Sectional Charts depict these areas using magenta hashed lines.
Alert Areas are used to inform pilots of areas that may contain a high volume of pilot training, or an unusual type of aerial activity. Nonparticipating aircraft should use extra caution when operating within these areas. These areas are depicted on Sectional Charts using magenta hashed lines.
Controlled Firing Areas, or CFAs, contain activities that are in a controlled environment, could be hazardous to aircraft and do not get charted.
Temporary Flight Restrictions are short-term blocks of airspace used to temporarily prevent/limit nonparticipating aircraft from entering that area.
Air Defense Identification Zones, or ADIZs, serve as the boundary between domestic US airspace and international airspace. Sectional Charts depict these with a magenta line and dots. Generally, aircraft must file an IFR or Defense VFR flight plan for any operations that enter or exit an ADIZ.
Military Training Routes, or MTRs, are routes around the country where military aircraft practice maneuvers and high speed operations sometimes at very low levels. On Sectional Charts, MTRs are depicted by gray shaded lines.
A VFR Flyway is defined as a general flight path, for use by pilots into, out of, through or near complex terminal airspace. These routes do not require an ATC clearance and are not a specific course that is flown, but merely a route that will keep the aircraft clear of the Class Bravo airspace.
A VFR Corridor is defined as airspace through Class B airspace, with defined vertical and lateral boundaries, in which aircraft may operate without an ATC clearance or communication with air traffic control. Essentially a corridor is like a hole through the class B airspace.
A VFR Transition Route is a published route through Class B airspace for VFR traffic flying through the area. Before flying a VFR transition route and entering class B airspace, a pilot must receive clearance from ATC to do so.
A Terminal radar service area, or TRSA, is essentially a class D airport surround by optional or voluntary class C-type radar service. TRSAs are depicted by black lines on a sectional chart.
National Security Areas are established at locations where there is a requirement for increased security and safety of ground facilities.
The areas above U.S. Wildlife Refuges, Parks, and Forest Service Areas are depicted by a blue line and dotted border and are usually labeled with name of the area. Pilots are requested to maintain a minimum altitude of 2,000 feet above the surface of these areas.
Radio Operation and Phraseology
The backbone of airborne communications is the Very High Frequency radio (VHF).
If two people try to transmit on the same frequency at the same time, the radio waves will overlap with each other and create an unpleasant and unintelligible warbling noise. The n-number is generally 6 characters long, and starts with an N in the United States, followed by a series of letters and numbers.
To help make transmissions more understandable, or "readable", pilots use a standardized set of pronunciations for each letter of the alphabet, called the phonetic alphabet. Instead of just saying "A,B,C" over the radio, a pilot or controller would say "alpha, bravo, charlie." Even some numbers have to be pronounced differently over the radio. The most famous is the number 9, which is pronounced "niner."
Respiration -
The air we breathe is roughly 21% oxygen, 78% nitrogen and 1% other gasses.
Hypoxia -
When the body, or part of the body, is deprived of adequate oxygen.
Hypoxic hypoxia -
The most common type of hypoxia experienced by pilots is "Hypoxic Hypoxia" where there is not enough oxygen available to the brain.
Pilots compensate for this in one of two ways; either by pressurizing the air inside the cockpit and cabin of the airplane, or by breathing 100% oxygen through a mask. This is why they also recommend going on oxygen at 10,000 feet in the daytime, but at 5,000 feet at night, as your eyes need extra oxygen to function at night.
Stagnant hypoxia -
Occurs when there is a decrease in blood flow to the cells in your body. Fighter pilots and aerobatic pilots experience stagnant hypoxia when the "G" forces created by quick changes of acceleration prevent the blood from flowing normally.
Hypemic hypoxia -
Occurs when the blood is unable to accept and transport oxygen. For pilots this may occur if carbon monoxide is entering the cockpit, perhaps from a leaking cabin heater.
Histotoxic hypoxia -
Occurs when there is enough oxygen in the blood, but the body's cells are unable to make use of it. This form of hypoxia can occur when the body has been poisoned by drugs or alcohol.
Symptoms of hypoxia -
The lack of oxygen creates visual and mental impairment. Symptoms are light-headedness, feeling of euphoria, dizziness, blue fingernails and lips (also known as cyanosis), tingling in the extremities, and headache. If you notice any of these symptoms it is important to increase your intake of oxygen.
Hyperventilation -
When under stress or experiencing anxiety, some people will breathe too rapidly. The resulting symptoms of dizziness, weakness, fainting, and tingling sensations of the lips, hands and feet are very similar to the symptoms of hypoxia.
Treatment for hyperventilation is accomplished by deliberately slowing your breathing down to a normal rate. If necessary, you can breathe into a paper bag.
Decompression Sickness -
For general aviation pilots and passengers, the encounter of decompression sickness is often due to scuba diving before a flight.
Symptoms of decompression sickness are joint pain, called "the bends", tingling sensations, seizures and unconsciousness. Treatment is accomplished by quickly descending to a lower altitude and administering 100% oxygen, if available.
Ear and Sinus Pressure -
Some people have voluntary control of the muscles that "flex" the Eustachian tubes and can equalize the pressure with little difficulty. Others must swallow, yawn, or chew to flex the Eustachian tubes. If these methods fail, you can try something called the Val Salva Maneuver. Hold your nose closed with your fingers and blow through your nose gently to clear your ears.
Stress and Fatigue -
Symptoms of fatigue include: reduced speed and accuracy of performance, lapses of attention, delayed reactions, impaired reasoning and decision-making, poor risk evaluation, reduced situational awareness, and low motivation to perform optional activities.
Motion Sickness -
This conflict between what you feel and what you see can lead to symptoms of motion sickness like nausea, sweating, feeling hot and faint, and finally vomiting. There are also some tricks you can use to prevent or reduce the symptoms: focusing your gaze on the horizon will minimize the disagreement between your eyes and your inner ears, or keep plenty of fresh air flowing into the cockpit, especially against your face. Consider even opening up the windows.
Night Vision -
The rods of your eyes are 10,000 times more sensitive to light than your cones and are responsible for your night vision. They also do not detect color, which is why colors are hard to see in the dark.
Alcohol and Drugs -
Federal Aviation Regulations prohibit flying within 8 hours of consuming any alcohol. Regulations also prohibit flying if you are under the influence of any drugs, legal or illegal. Some over-the-counter drugs, especially those for colds and allergies can impair your physical and mental performance.
Layers of the Atmosphere -
The lowest layer of the atmosphere is called the troposphere. This is where almost all weather occurs. In the troposphere, the temperature decreases and the air becomes thinner.
The stratosphere extends from the tropopause up to around 31 miles from the Earth's surface. In this layer, temperature increases with height, making it very stable and give anvil clouds their famous flat tops.
The next layer of the atmosphere is called the mesosphere.
The thermosphere is next and extends from 53 miles up to 375 miles above the Earth. Being one of the outermost layers, the air here gets bombarded with ultraviolet and x-ray radiation from the sun.
The last layer of the atmosphere is called the exosphere and is the outermost layer, and atoms and molecules of the atmosphere escape into space.
Basic weather circulation -
The Coriolis force, a force created by the rotation of the Earth, causes the circulation of air to flow and break up into three distinct cells.
The Earth circulation patterns always try to maintain a balance. This means that air flows from areas of high to low pressure. In the northern hemisphere, a low-pressure system will circulate counter-clockwise as it flows into the center. A high pressure system will circulate clockwise as it flows away from the center.
Air masses and fronts -
Air masses are large regions of air that have similar characteristics from the surrounding area. The boundaries between these two air masses are referred to as fronts.
A warm front occurs when a warm air mass overtakes an air mass of a colder temperature. Warm fronts usually contain high humidity and have more "stratoform", or layered, clouds along the frontal boundary.
A cold front occurs when cold, dense air overtakes warmer air. The rapid upward motion will cool the air and form cumulus clouds, which could eventually develop into thunderstorms or even form a squall line.
A stationary front occurs when two air masses meet, but neither one moves the other out of the way. The last type of front is called an occluded front. Occluded fronts form when a fast-moving cold front catches up to a warm front.
A stable atmosphere is one where, when the air is lifted, that air will return to its original position.
Hazards -
Thunderstorms need three main ingredients to form: sufficient moisture, an unstable atmosphere, and a lifting mechanism (like a front) to start it all.
Wind shear is any change in wind direction or speed over a short distance.
Icing is a very dangerous condition that can drastically affect the performance of the aircraft.
Icing detail -
Rime ice forms when small water droplets impact and freeze on the airplane.
Clear ice is formed when larger water droplets impact and freeze on the airplane.
The third kind of icing is called mixed icing. Areas with mixed icing are simply areas that have a combination of both rime and clear icing.
Weather Products -
The 2 approved preflight methods include: calling 1‐800-WX-BRIEF and DUAT
A METAR is an hourly weather report that includes the airport identifier, time of observation, wind, visibility, runway visual range, present weather phenomena, sky conditions, temperature, dew point, and altimeter setting.
A PIREP, or pilot report, is a type of weather report made by pilots, recording actual weather conditions that he or she is experiencing.
There are three types of imagery commonly used by pilots: visible, infrared, and water vapor. Each image is updated about every 15 minutes. Visible satellite images display reflected sunlight from the Earth's surface, clouds, and particulate matter in the atmosphere. Infrared (IR) images display temperatures of the Earth's surface, clouds, and particulate matter. The water vapor imagery displays the quantity of water vapor in the air.
Radar images are graphical displays of precipitation and non‐precipitation targets detected by weather radar.
Airmen's meteorological information, or AIRMET, is a concise description of the occurrence or expected occurrence of specified en route weather phenomena, which may affect the safety of aircraft operations.
SIGMETS are issued for conditions of severe or greater turbulence, severe icing, a widespread dust storm, or a widespread sandstorm.
Convective SIGMETs are issued for: thunderstorms, lines of thunderstorms, embedded thunderstorms, tornados, hail greater than or equal to ¾ of an inch, or when wind gusts of greater than or equal to 50 knots (at the surface) are reported.
A Terminal Aerodrome Forecast, or TAF, is a forecast of the expected weather conditions within five statute miles of the center of the airport.
The Area Forecast, abbreviated by the letters FA, is a weather forecast for a large area, the size of several states.
Wind and Temperature Aloft Forecasts are computer prepared forecasts of wind direction, wind speed, and temperature at specified times, altitudes, and locations.
Short‐Range Surface Prognostic Charts, or Prog charts, provide a forecast of surface pressure systems, fronts and precipitation locations in the future.
Factors -
Aircraft manufactures publish performance charts to allow pilots to calculate the aircraft's performance numbers, including such things as takeoff and landing distances, climb rates, true airspeed, and fuel consumption.
If we consider an airplane in level flight, the wings are producing the same amount of lift as the weight of the airplane. If the plane weighs more, the amount of lift the wings have to produce increases as well
Air density is a measure of how far air molecules are spaced apart.
The higher the temperature of the air, the more space the molecules take up as they move around. This means that higher temperatures result in a decrease in air density.
Density Altitude -
A better way for pilots to make sense of how density affects airplane performance is to use something called Density Altitude.
The standard conditions for 0 feet elevation, or sea level, consist of a temperature of 15 degrees Celsius and a pressure of 29.92 inches of mercury.
Takeoff Performance -
The manual has performance charts for the different phases of flight including: takeoff, climb, cruise, and landing.
The aircraft's airspeed indicator reads off what we call "Indicated Airspeed".
On days where the air density is low, aircraft will have to actually travel faster to get the same indicated airspeed. This results in increased takeoff distances.
Another factor to consider in the performance of the airplane is its weight. Heavier airplanes require more power and thrust. Simply put, the heaver the airplane is, the lower its performance would be. For takeoff distances, a heavier airplane would use up more distance in their roll. This is because it would take more power to get the airplane rolling and accelerate to rotation speed.
Climb Performance -
Temperature will also affect these numbers too. Weight changes will also affect these performance values.
Cruise -
If we also look at the "range" and "endurance" charts, we can see how changing the RPM of the engine can greatly affect both how far we can travel, and how long we can stay in the air. By simply going slower, we can actually travel over 100 miles farther on that one tank of gas. If your destination is about as far away as your current maximum range, it may be wise to slow down to a lower power setting. You'd be able to make it all the way there, without needing to stop for fuel.
Landing -
Lighter airplanes will be able to fly a slower approach speed for landing, and will have less momentum and less energy to dissipate once on the runway, resulting in a shorter rollout.
Wind will also affect the landing roll, just like with takeoffs.
Pilotage and Dead Reckoning -
The most basic form of navigation is Pilotage. Pilotage is the use of fixed visual references and landmarks along the ground to guide yourself to your destination.
All checkpoints should consist of prominent features that are easily identifiable from the air during the flight. Things like roads, intersections, rivers, lakes, railroad tracks, power line, and even other airports make for sufficient checkpoints.
Dead Reckoning is the process of navigation solely through the use of mathematical computations, based on time, speed, distance, and heading. If you know how fast you are going, and how long you are flying, you can calculate the distance you've traveled. This is done through the formula: Rate X Time = Distance.
Radio Waves -
Ground Waves are lower-frequency waves that travel close to the surface of the earth, and will follow the curvature of the earth.
Sky Waves are higher-frequency waves that can also travel for long distances; but instead of following the curvature of the earth, the waves are refracted, or "bent", by the ionosphere, and sent back down to earth.
Space Waves consist of Very-High-Frequency waves, or higher, that neither bend nor refract. These waves travel in a straight line, passing through the ionosphere, and allow navigation from space. Most major navigation systems these days operate with signals broadcasting as space waves.
NDB -
One of the oldest types of navaids still in use today is called the Non-directional Radio Beacon, or NDB.
An NDB is simply just a ground-based AM radio transmitter that transmits radio waves in all directions.
To navigate via NDBs, pilots need have installed in their aircraft an Automatic Direction Finder, or ADF. The face of an ADF contains a needle that points to the relative bearing of the NDB. The relative bearing is the number of degrees measured clockwise between the aircraft's heading and the direction from which the bearing is taken from.
VOR -
VORs are oriented to magnetic north and transmit radial information outward in every direction.
Since a VOR's radials emit out like spokes on a bicycle, the closer the pilot flies to the VOR, the more sensitive the instrument gets.
There are three service volumes that a VOR can have Terminal, Low, and High.
Distance Measuring Equipment (DME) -
To obtain distance from a station, your aircraft's DME receiver first transmits a signal to the station. The station then replies back. The aircraft's receiver then measures the time it took to complete the trip, and converts that into distance.
Because of that, DME gives the pilot something called a slant range distance. This means that the distance shown is actually going to be the exact distance to the DME station, not the distance across the ground.
Global Positioning System (GPS) -
The Space Element consists of a minimum of 24 satellites in 6 orbital planes around the Earth.
The control element consists of ground-based monitoring stations, a master control station, and ground antennas around the world. The goal of the control element is to ensure the accuracy of the GPS satellite positions and the accuracy of the atomic clocks on board.
The user element consists of the combination of the antennas, receivers, and processors in the airplane, that receives the signal and calculates your GPS position.
The idea of how the GPS works is based on a principle called Pseudo-ranging. This is the name for the process that allows us to calculate our distance, not by actually measuring distance but calculating it with a time calculation.
GPS receiver calculates something called Receiver Autonomous Integrity Monitoring, or RAIM. This is the system the receiver uses to verify the usability of the received GPS signals, which warns the pilot of malfunctions in the navigation system.
To improve the accuracy, integrity, and availability of GPS signals, something called Wide Area Augmentation System, or WAAS was designed.
As the GPS signal reaches Earth, it is received and monitored by ground-based wide-area reference stations. These stations monitor the GPS signal and relay the data to a wide-area master station. At the master station, a correction to the GPS signal is computed. A correction message is prepared and uplinked to one of the geostationary WAAS satellites. Any GPS receiver that is also WAAS capable will be able to receive the correction message. The receiver will then apply this correction into its GPS position calculation and display to pilots an even more accurate position.