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Charts, Airports and Procedures
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Contents:

VFR Charts; ...Runway lights; ...All Available Information; ...Aviation Charts; ...Reading the Sectional;
...VOR box; ...World Aeronautical Charts (WAC); ...Class Bravo Airspace; ...Phonetic Alphabet and Time Zones;
...Its about Miles and How they came to be; ...It's about time; ...Way to Go; …Controlled Airports;. ...Towered Procedures; ...Class D Airport Departures; …At runway you can request; …Class-D airport arrivals; …Two-mile reports; …Air Traffic Control; …A Pattern to Patterns; …

Item
Planning the flight should take twice as long as the flying of your plan.

VFR Charts
NOAA Aeronautical Chart User's Guide is a source of chart terms and symbols with charting symbols organized by chart type. Available from the Government printing office Golden Gate Ave in downtown S. F. at 1-800/638-8972. State charts are obtained from the Aviation Dept. from each state. Years ago I wrote to all the states on a route across the country and back. I received 37 pounds of charts, guides, and information. Do it.

VFR area charts (TAC) are scaled 1:250,000 or 3.5 nm per inch. Sectional charts are 1:500,000 or 7 nm per inch. WAC charts are 1:1,000,000 or 14 nm per inch. Sectionals are replaced every 6 -months as are area charts. Where TACs occur in sectionals they are outlined in white. WACs do not carry airport communications information or Classes D or E airspace. MTRs are not shown either. TACs are used to clarify the separation of Classes B, C, and D airspaces.

To fly without a chart or an out-of-date chart is an FAR violation since you do not have all available information. Even IFR pilots should have VFR charts available. Every color, number and mark on a sectional is significant. I do not believe it is possible to know all the ramifications that exist on a sectional. Even keeping up with the changes is daunting. The more complex the area the more likely it is that there will be errors. Your flying proficiency is directly related to knowing your charts.

AIM 2-3-3 presents threshold stripes for IFR runways such that 4 stripes = 50', 6 = 75', 8 = 100', 12 = 150'16 = 200'. Touchdown zone marks are 500' from beginning of threshold lights. I50' long aiming point marks are 1000' from beginning of threshold lights. Edge lights are usually white but on IFR runway yellow exists on last 2000'. IFR centerline lights are red and white for the last 2000' and red for the last 1000'. Taxiway turnoff lights are now called taxiway leadoff lights and are alternating green and yellow from the runway centerline to the runway hold bar. The new obstruction lighting system is in the AIM 2-2-3

Land and hold short lights have pulsating white lights at the LAHSO point. The runway end lights are red toward the runway and green from the approach side. During low visibility stop-bar lights extend across the taxiway to warn of the hold short position they are called runway guard lights. Yellow clearance bar lights are at the holding position of some taxiways. An airport beacon with a green and two quick white flashes indicates a military airport. A beacon operating at a controlled airport during the daytime indicates that the airport is below VFR minimums either of visibility (3 miles) or a ceiling less than 1000'.

FAR 91.103 says, "Each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight. This includes weather, fuel, alternates, plane performance, runway/airport information, and possible delays. Radio frequencies, ATC services, terrain, airspace, and local services are not in the FARs but belong in your "All Available Information" kit. Materials such as the AIM require that you have a subscription to remain current. The FBO AIM will not satisfy the AAI requirement. Materials are available for on site use at all ATC facilities.

First get your charts, a World Aeronautical Chart is good for planning long trips, a sectional set is required but not mentioned specifically in the FARs, a VFR Area chart is required by FAR if you plan to fly in, under, or over Class B airspace. The first planning step is to draw a course line on the WAC and then transfer it over to your Sectionals and Area Charts.

Using these course lines you are ready to locate any Special Use airspace along the route to note minimum altitudes, hours of operation, and areas where extra precautions may be advisable. Use the Airport/Facility Directory and any available airport guide to get enroute airport information to elaborate on the rather limited chart data. You could use 'Post-it's' but I prefer a black marker to give pattern altitudes and frequencies. This is a good time to get any special frequencies that are not normally available such as Center. You may need access to IFR charts for these as well as IFR approach/departure courses and altitudes. In low visibility conditions you must plan to avoid IFR routes.

All information from charts and publications may be out of date anywhere from thirteen days to six months. The accuracy of your information must be verified by getting all local and distant NOTAMs along the route. Local NOTAMS-L may not be available until you approach an area while airborne. NOTAMs are the latest valid information and may extend, cancel or replace any prior information that is printed.

While enroute listen to Flight Watch on 122.0 or even on the following frequencies that are intended for high altitude aircraft but are available as an option to a pilot who is flying in isolated areas such as behind the Sierras; 135.7 Oakland, 135.92 Seattle, 133.02 Salt Lake, and 135.9 Los Angeles. Many VORs have weather broadcasts where the VOR information box has a small black square in the corner. TWEBs and HIWAS may be broadcast over navaids.

It is not against the FARs to fly while having out-of-date charts in the aircraft. You may even used them but if such use should cause an accident or an FAR violation. An additional action can be brought against you for
not having current charts.

The first charts were published in 1926 of the principle airways. They were long and narrow and extended only 40 miles to
each side of the airway. 1 inch equaled 8 miles. (A sectional has 1 inch to 7.8914 miles). Water was colored blue, cities
yellow, railroad black and highways white. Airports were red circles. Sea level land was dark green, at 1000' it became
|light green, at 2000' light brown, above 3000' darker brown. The charts were useful but so narrow that any diversion for
weather could fly you off the map.

A chart will not tell you where you are unless you know where you are. Not knowing where you are is the one of most
stressful things that can happen in flying. Reading a chart under stress is not likely to be a successful situation.

Open the San Francisco Sectional and locate the lower left corner that has 36-degrees with 125-degrees below and to the right. Now fold the chart so that only ocean is visible except at the upper right corner which shows Point Reyes. Leave the Legend to the right out flat as you not that the vertical line is not straight but has a slight curve. The bottom line is also curved, as you should note by the width of the white margins. Note the caution box below the 125-degrees, related to uncharted hazards below 200 feet.

The 36-degree line is the degrees of Northern Latitude it is parallel to the 37-degree; line about 9 inches above. The top of the sectional goes slightly beyond the 40-degree; line of latitude or 40th parallel. The space between every degree on the sectional is divided into 60 divisions and each division is a nautical mile. This is true only on the vertical lines. There are sixty divisions between the vertical lines but they vary in distance from 48 to 45 nautical miles due to the tapering of the distance toward to pole. You never measure distance on the horizontal lines of latitude.

Vertically between 36-degree; and 37-degree; there are divisions and subdivisions. Half way between every degree either vertically or horizontally there is a full line marking the thirty-minute (30')or halfway point between degrees. It is very easy to confuse a 30' line with a degree line. Degree lines will have their numbers to the lower left at every interior intersection. Horizontally each nautical mile is one-minute. There are sixty minutes in every degree. From the degree line every five degrees has a marking that extends farther to the left; every ten degrees has a marking extending farther both left and right. Use of these subdivision markings makes it easier to count degrees.

Go back to the lower left corner of the sectional. Count up the 125-degree; line of west longitude or meridian five spaces. Mark this line and then repeat the process on the 124-degree; meridian. Use a straight edge to connect the two points with a line. This Line is knows as the 36-degrees 05' N. Go back to the left corner and count over on the 36-degree; parallel for 15 spaces and mark the crosshatch. Go up to the 37-degree; parallel and repeat the count and mark. Draw a vertical line between the two marks. This line is known as the 125-degree; 15' W line of longitude or is it the 124-degree; 45' W meridian. Which?

We have created a problem for ourselves. 36-degree; 05' N worked because we were counting toward 37-degree;. By counting from 125-degree; to the right we may tend to use the 15 count when it is actually the 45' point from 124-degree;. I deliberately tried to expose you to one of the most common errors in locating coordinates. You must always start your count for latitude from the bottom and the count for longitude from the right. The next most common error is in not using a long ruler to draw your lines. It is very easy to draw a line between two points that are not going to give a parallel line.

Where these two lines cross is a point that is unique in the world. 36-degrees 05' N-124-degrees; 45' W. Every place on the earth can be so identified and located. Locate Mt. Whitney near Death Valley and see what coordinates you get. Check with the coordinates given on the chart legend. Practice at least ten different locations by giving yourself coordinates that would be located on the San Francisco Sectional. Next mark at least ten airports on both sides of the sectional and determine the coordinates.

To locate a particular airport for which you do not have a designator. You can put the geographical coordinates into your Loran or GPS and the navaids will work just as well. Fifteen years ago I did this while going to Medford, Oregon from the Nut Tree. Crossing the threshold the Loran indicated 1/2 mile to airport center. (I taught LORAN in WWII)

The quadrangles bounded by the ticked lines are but 1/4 of the area in a degree square. It isn't a square or a rectangle but it does measure 60' to a side. Every quadrangle is 30 nautical miles high but the width is quite variable. Call them wreckedangles? Each figure that has land has a highest known obstruction elevation. The given figure is rounded upward to the next hundred and then an additional hundred is added. Maximum elevation figures on a sectional have a fudge factor to account for possible errors. After rounding any elevation to the next highest hundred, another hundred is added. In mountains an additional 300' is added. These margins may only partially correct for altimeter setting errors. You are required by FAR to have an altimeter setting from within 100 miles. The closer the setting location the better.

The sectional aeronautical chart is essential to all forms of visual navigation. Your eyes use a comparison of land features to chart features to determine how relationships compare. When comparisons match, you know where you are.

A sectional is aligned to true north. The Lambert Conical Projection of the chart makes all straight lines very nearly the direction you fly before figuring in isogonic variation and deviation. This works very well when you know that the winds given by the FSS and Weather Bureau are also measured by direction from true north.

The lines of longitude and latitude on the sectional divide it into a series of wrecked-angles (sic) with 30 ticks marked on each side. Only the north-south ticks can be used for distance measuring since the lines of latitude are parallel. Each wrecked-angle has a Maximum Elevation Figure, which, within 100', tells the MSL altitude required to overfly all obstacles.

Within many wrecked-angles the topography is shown in eight colors which shade from green to dark brown to indicate altitude. Most chart symbols resemble earth features. Small roads are shown only when deemed useful for navigation. Fly with the chart open and pointed in the direction you are going. In each quarter of a degree depicted there is a maximum elevation figure. In most areas this figure is rounded to the next higher 100' but in mountainous areas it is rounded to the next higher 100' plus an additional 300'.

Airports are either magenta (uncontrolled) or blue (controlled). It is important that the pilot become totally familiar with the chart legend as it applies to information available at the airports and through the use of radios. Airspace depiction is shown by types of line/color combinations to cover Classes B, C, D, E, and G. It is illegal to fly without a current chart for the area.

The Hazardous In-flight Weather Advisory Service is broadcast over VORs that have a Small solid square in the lower right corner of the VOR information box.

Arcata, California VOR gives TWEBs or Transcribed Weather Broadcasts about route information, NOTAMs and special information. A solid circle around a white T in the upper left corner of the VOR box shows this ability.

The altitude of your transponder mated encoder is always based on 29.92 and computer adjusted for the ATC read-out. Nothing you do to your altimeter will make a difference in what ATC sees. Every new radar controller is required to confirm your cockpit altimeter setting to compare with his read-out.

WACs have half the scale of Sectional Charts so the price is cheaper for the area depicted. Class B and C airspace is only outlined without altitudes. Class D and Class E surface (CZ of non-tower) is not shown at all. Space limits have eliminated many obstacles, towns, and frequencies. Maximum elevation figures (MEF) cover 60 nautical mile wrecked angles (sic). WACs are best for fast airplanes or for long flight planning. (Required Practical Test Knowledge-frequent oral test question) WAC charts show MOAs but do not show MTRs. The width of a MTR can vary up to ten miles to each side. See AIM 3-41 +.

Expect to pay a landing fee if landing at a Class B airport. Wake turbulence and extensive taxiing to expensive parking is to be expected. If you do not have the rating and equipment for flying into Class B you can expect to hear from the FAA. FAR 91.129 gives the operational requirements. Most of the large Class B airports do not allow student operations. A student endorsement is required in those Class Bs that allow student operations. You cannot enter Class b unless your are given a clearance.

FAR 91.131 requires you to have an encoding transponder. Your transponder will warn TCAS equipped aircraft of your location and proximity. VFR aircraft are not required to have a VOR but you will be expected to abide by any headings and altitudes assigned regardless of your altitude and location. You are usually free to select your own route and altitude below Class B but you should advise ATC of any changes you Class C or D field that will give the same amenities at far less cost. At any unfamiliar airport you should request progressive taxi instructions. Prior to departures in underlying Class B airspace you will be given specific instructions as to direction and altitude restrictions. Readback all such restrictions as they occur. FAR 91.117 limits speeds below Class B to 200 knots or slower. Speed in Class B has an upper limit of 250 knots.

I have yet to find a reason to fly into a Class B airport. There is always an underlying information and make sure that you understand what is expected.

In 1914 the U.S. Army adopted a phonetic alphabet but Spanish pronunciations created problem In 1927 a worldwide agreement of words and spelling was reached but some words were uncommon. In 1952 an International Civil Aviation Organization (ICAO) alphabet was made using Able, Baker, Charlie, Dog but it too had problems. The current alphabet was adopted in 1956.

Related to this 1996 version are the names of the time zones around the globe. Alpha time zone begins 7.5 degrees west of Greenwich, England and extends to 22.5 longitude westward. Each successive 15-degrees of longitude is given a alphabetic name. Eastern time is named Echo and Pacific time s Hotel. Even during daylight savings time the names remain the same. All aviation time is referenced to Zulu.

Zulu time is relative to the sun, the exact same moment all over the world is recorded by clock time in Greenwich. Why Greenwich? In 1735 John Harrison, a carpenter designed an accurate chronometer. By knowing just when noon occurred in Greenwich with the chronometer, a navigator could use an astronomical table to determine his longitude.

Under the Roman Empire, Rome became the center of the western world. All roads led to Rome and all distances were measured from Rome. The distances were based upon one thousand Roman paces of the Roman soldier. A Roman pace is equal to two of our steps and very near 64 inches. The Latin for a thousand paces is 'mille passus' from which we derived the word mile.

Many different miles of differing length.have existed from the old London mile of eight furlongs. This was measured by German 'feet' but at the time of Queen Elizabeth a shorter foot was used giving a distance of 5280 feet. which is now the statute mile.

The first paths for ships were called Porotan Charts. These were lines drawn across the Mediterranean between the coastal ports. Where many of these lines crossed the mapmakers would draw wind roses. The wind rose initially varied but settled on the eight points. The predecessor to the compass rose and our eight-wind direction terms.

Thales of Miletus (640-546BC) made a gnomonic projection (use of shadows) of the region where he lived. Hipparchus in the 2nd century BC had used sterographic (showing heights) and orthographic projections (perspective). Eratosthenes in 3rd century BC calculated the size of the earth circumference to be 24,000 miles. He developed a 16 point wind rose and use of 'degree". He also wrote a description of known world.

Ptolemy, a 2nd century Greek, made a world map and made a world size error when he calculated size of world's circumference to be only 18,000 miles. Jean Picard did not correct this until 1669, 200 years after Columbus. Eratosthenes' calculations had been lost to the western world. Ptolemy used the first conic projection plane map with the top as north. This made possible drawing of rhumb (one direction) lines from point to point on the globe. He devised the 60 minute and 60 second divisions of the 360 degrees in a circle. A mile at sea, on this world of Ptolemy, was essentially equal to a mile on the land. The length of a statute mile was 1000 (mille, from the Latin) Roman paces. A Roman pace is two of our steps. Each Roman road had occasional small obelisk statues placed to indicate the distance from Rome much as Mexico today does from Mexico City. Hence, statute miles.

A 1466 Chart of Nicolaus Germanus divided the degree into 60 equal spaces called miles. This was based upon an earth of 18,000 mile circumference and gave us a nautical mile the same length as a Roman statute mile. Other cartographers including Hipparchus and Mercator gave us a world with an overlying grid with numerical markings of longitude and latitude. Gerardus Mercator (Gerhard Kremer), Flemish, in 1569 drew world globe map with 180 degrees E/W longitude 0 to 90 N/S latitude. He made errors which were corrected by Edward Wright who published the computations required as "Meridional Parts" and made this knowledge universal. In combination, we now had a world, which could be mapped in degrees of longitude and latitude. Each degree of longitude had divisions of 60 miles equal to a statute mile and each mile was again divided into 60 units called minutes and each minute was again divided into 60 units called seconds.

This was the kind of map and scale used by Columbus. The navigators of his time had not the timing device to make possible the exact determination of longitude. The best 15th Century data available to Columbus came from Ptolemy. The error by Ptolemy directly resulted in Columbus' declaring that he had reached and was exploring India. Columbus thought he had sailed through enough degrees of longitude to reach India. He may well have, had the world been 18,000 statute miles in circumference.

When the world was computed to be 24,000 statute miles in circumference all the degrees and their divisions were longer and did not conform. More accurate computation of the world's circumference kept changing and finally came to 24,902 statute miles. The circumference of the earth has always been measured as 21,600 nautical miles (360 degrees X 60 nautical miles per degree). However, the individual nautical mile has ballooned by nearly a third through this recalculation of the earth's size. The Nautical or Sea Mile is the length of a minute of latitude. The U.S. Nautical Mile at one time was 6,080.27 feet. This figure was revised to 6,076.i feet/ This came to be know as the International Nautical Mile. The British use the Admiralty Mile of 6,080 feet. Some countries still use the 1929 International Hydrographic Bureau mile of 6,076.097 feet. The Geographical Mile uses the Equator as a great circle and a minute mile is 6,087.1 feet long. For many of the same reasons the U. S. has failed to convert to metric, later cartographers decided to use statute miles for land and the expanded nautical mile at sea.

Now we can see the background for the difference between nautical and statute miles and Columbus' reasoning. We have Columbus sailing around an earth at least 1/3 larger than he was led to believe. Based on available knowledge Columbus was quite justified to assume that he had actually reached and explored India.

For the navigator, it is very important that distance only be measured along the lines of longitude, which has evenly spaced tick marks throughout. The elongated orange peel appearance of the region between lines of longitude means that various latitude lines will have tick marks at differing intervals although always 60 ticks per degree. Only at the Equator do the tick marks correspond to the size of those along the lines of longitude.

Johann Henrich Lambert from Alsace devised the Lambert conformal conic projection in which the line you draw is the way you go. This is the charting used on aircraft. As with any flat map of a round surface it has areas of inaccuracy. Sectionals are most inaccurate (stretched) in the six inches at the top and bottom. The center ten inches of the sectional for 5 inches up to five inches down from center is somewhat contracted in size.

A sailing ship's speed over a nautical a mile was, historically, measured by means of a knotted (knots) rope tied to a log. A sand filled timing glass would be used to measure the time from leaving the log dead (much as a dead man might appear) in the water (dead reckoning) and the number of evenly spaced knots passed along the rope. All of this would be recorded in the logbook. Since the chronometer was yet to be invented, sailors had no way to determine longitude except by this dead reckoning. Within crude limits, speed and compass indications could be used to determine estimated distance and estimated longitude. Magellan in 1519 had access to charts, globe, theodolites, quadrants, compasses, magnetic needles, hourglasses, and timepieces. He was unable to determine exact longitude.

An 18th Century a chronometer (weighed over 36 pounds) was first used to get longitude. A chronometer differs from a clock or watch because it has a temperature adjustment for greater accuracy. Captain Cook in 1768 had three different clocks for his voyage. In 1779 he sailed with 4 chronometers and a nautical almanac which enabled him to determine longitude. The very first effort to make a calculator was financed by the British to make the making of the nautical almanac easier. The effort was stopped when the mechanical calculator was only a year from being completed. The original design was completed in 1991 and found to work accurately.

Interesting to speculate where the world would be had it been completed in the 1700s. 30 years ago I knew a pharmacist who spent his evenings at an all-night pharmacy working out prime numbers on rolls of butcher paper with a pencil. Did we miss a 300-year head start on computers by so little?
_______________________________________________________________________
Revolutions per minute - rpm
First counted by paddle wheel ship captains._____________________

The ancients recognized the pole star as being a constant reference for determining direction. The Norsemen in the 11th century used a needle of magnetic iron inserted in a straw and floated on water to point to the pole star. Petrus Peregrinus de Maricourt invented the pivoted floating compass with lubberline and sight for bearing. The modern compass is little more than one hundred years old.

The compass card, due to wind rose origins is older than the magnetic needle. Names of the cardinal compass points are from the ancient terms for wind direction.

Variation was understood by 1800 as a problem. Edmond Halley at end of 17th century mapped lines of variation and drew isogonic lines (lines of variation) on his maps. George Graham showed that variation was subject to diurnal (seasonal) changes with variation being less in winter.

John Smith wrote about deviation in 1627 by John Smith. He saw it as a problem encountered through use of metal nails in his compass box. Captain. Mathew Flinders in 1801-2 found way to correct by use of "Flinder's Bars as did Lord Kelvin through use of Kelvin spheres. Placement of soft iron spheres at sides of compass could be used to correct deviation.

The development of the gyro compass began in 1851 when Leon Foucault used suspended cannon shot on a long wire pendulum to show the rotation of the earth as well as the inertia of the free swinging ball. By 1852 he had created the gyroscope but had trouble applying continuous power. By 1900 the electric gyroscope was invented by both Elmer A. Sperry and Anschutz-Kampfe of Germany. By 1911 gyro compasses were in use soon to be followed by gyro repeaters (selysn(sp) units) and gyro pilots.

I like to think that avoiding airports where you lack competence is a sign of good judgment. I have never flown into SFO. I've never had a reason and haven't looked for one. I have been into Boston's Logan but I did not feel welcome. Meigs field in Chicago was an unhappy experience because of the management. They had me park in a jet tiedown at $60 per night in a C-150 after they delayed giving me fuel until after closing time. All, very deliberate.

The basic rule is that you should not fly into a situation for which you are neither knowledgeable nor trained. Training would teach you to study the airport diagrams, checkpoints for call-up, arrival routes, and post-landing procedures. Frequencies including those of clearance delivery, the most likely unfamiliar procedure, are organized in anticipated order. You may want to rehearse or even write down what you expect to say. Expect to copy some sort of arrival and departure clearance procedure with a read-back for an accuracy check. Your ability to listen is going to be just as important as your talking. Small aircraft are an endangered species around large aircraft.

A week ago, 10-10-98, I flew into Santa Ana's John Wayne Airport in the L.A. Basin. Cloud altitudes and poor visibility and unfamiliarity made the use of ATC assistance very necessary. We found that one one runway
At Santa Ana was in use. The G. A. runway was under repair. IFR would have meant extensive delays and routing.

By opting for a VFR arrival we had more pilot control of our options. Our First choice was to remain on top of the clouds at 4,500 as long as we could. The limiting factor of this decision was the need for an area large enough for a VFR descent below the clouds. We found and used such a hole some 15 miles from the airport. In addition to vectors we used GPS to retain our situational awareness.

As we neared the airport we were told to circle some four miles to the north while awaiting instructions. After two or three turns we were Given a heading and told to fly directly over the airport and tower to make a left downwind to the runway. We were filtered in between two airliners for our landing.

Two days later our departure was arranged quite contrary to our VFR requests. We were told to climb to 8500 and proceed VFR through the Class B airspace on a 310-degree heading. We had requested VFR through the
corridor at 4500. The higher altitude made us fly into stronger headwinds but avoided much heavy traffic both in weight and numbers.

As we departed Class B we descended and turned to get more favorable winds. Several years previously we had been forced to fly completely around the Class B airspace on an IFR flight to the same destination.
Interesting how choices can make such a large difference.

Don't expect a welcome mat if you're flying a C-150. An arrival at a major airport of a C-150 could back up traffic for miles. Coming into Class B airspace requires a clearance, an encoding altimeter and communications equipment. Be sure you know the procedure for making transponder code changes as well as the proper terminology. You are probably VFR so you must remain clear of clouds and have three mile flight visibility. Your greatest aircraft hazard is from behind.

Follow all instructions as precisely as you can. If in doubt, get clarification. When you need help ask for it. Don't loiter. Such instructions as 'hold short' must be read back. As a stranger, it might be wiser to read back everything every time. Expect
to hear changes in your instructions. Keep ATC advised of your flight conditions. Allow plenty of room so ATC will have
time to make adjustments. Course changes are usually easier for ATC to make than altitude changes.

Towered Procedures
As a local or unfamiliar pilot you must be aware of what is changing, different, and unfamiliar. Local NOTAMS are required reading. Airports are like the weather, always changing. Airports with precision approaches have approach lighting systems of 2,400 to 3,000 feet with red lights to each side of the threshold outside of the white lights. The extended white lights hare a single line of sequenced flashing white lights. (ALSF or SSALR) Non-precision approaches may have
MALSR systems with white lights and flashing red centered on the runway. Most lights have variable intensities that are
controlled by the tower or by the pilot when the tower closes.

VASI and PAPI lights are guides to the visual approach slope. The more red showing, the lower the aircraft is on the
approach slope. Any flight below the slope is intruding on obstacles and is contrary to FARs. REIL lights are white
strobe lights that show each side of the threshold. Runway edge lights on instrument runways are white, yellow or red
depending on the amount of runway remaining. Blue lights show the edges of taxiways while green show the middle of
taxiways. Red stop bar lights across a taxiway centerline are runway holdshort indicators. Never cross stop bar lights
until they are turned off and an ATC clearance says to proceed.

When taxiing in an unfamiliar situation you should read back all taxi instructions and get directions if any part of an
instruction is unclear. Night taxiing should keep strobes and landing lights off for the benefit of other aircraft until cleared
for takeoff. ATC is required to get a 'hold-short clearance readback from you but good practice is to read back every
taxi clearance.

Class D Airport Patterns and Procedures
Except for traffic conditions where ATC (Air Traffic Control) has override powers, airport pattern directions, and altitudes are decided by local jurisdictions.

Class-D airport departures
From a single runway there are nine standard departures that may be requested if there are no special considerations. If departures can be made from both ends then we have a total of eighteen. If left traffic is standard there are two of these eighteen that need not be requested. They are the two left standard (45 degree) departures, one from each end.

1. If no request is made you are expected to make a left standard departure. The tower may ask for confirmation of as standard departure just to make sure.

At runway you can request...
1. straight out
2. left crosswind
3. left downwind
4. left 270
5. right standard
6. right crosswind
7. right downwind
8. right 270

...on course (destination) may be appended to any of these. You can optionally just say request left/right turn on course (destination) The advantage of naming a destination is that other aircraft are given a more specific idea of the flight line you will be flying. A low visibility or weather related departure would be to request a climb in the pattern.

Typical call would be..."Podunk tower Cessna 1234X ready 32 request right 270 on course Lost Hills" No punctuation should be used in talking or writing airplane.

Class-D airport arrivals
To a single runway there are seven standard arrivals. There are two non-standard arrivals that are relatively hazardous. If no special considerations interfere any of the seven may be requested. If the pattern direction is known a 45 degree entry into the pattern need not be requested. However, the tower must be advised that you will report right or left downwind. As a standard procedure, except for the downwind entries, all other arrivals require a two-mile report unless otherwise advised. The purpose of the report is to allow the tower time to locate you and plan a safe sequence for
your arrival.

--straight in
--right base
--right downwind
--right standard (45)
--left base
--left downwind
--left standard (45)
--direct entry to left downwind (not recommended)
--direct entry to right downwind (not recommended)

All of these can be modified by pilot request or ATC suggestion. A modified entry may be at other than a precise number of degrees relative to the runway. I recently heard an aircraft over the airport request and be approved for an overhead arrival. Ask and you may receive.

A typical call might be..."Podunk tower Cessna 1234X the dump at 2100 with Alpha request right base 32 will report two-mile base" Again, no punctuation should be used when writing or talking airplane.

The standard 45 entry has some dimensions that can be used to standardize a landing approach. The ideal towered runway is about 5000', close to a mile. Entering on a 45 and aiming at the runway threshold and turning downwind at mid field would place the aircraft a half-mile from the runway and a half-mile from abeam the numbers. Flying from the numbers to the 'key position would be another half-mile. Base would be a half-mile as would the final. This gives the aircraft a two-mile landing procedure with the first half-mile for pre-landing procedures, the downwind extension for slowing, trimming and configuring the aircraft, the base leg for descent and setting the length of the final approach.

The two-mile reports for the straight in and base arrivals can be segmented much as the standard arrival and used to organize your landing procedures.

Two-mile reports
The two mile report should be 'measured' from the runway threshold. the 'measuring can be done for the straight-in by using a known site directly in line with the runway or by using a call that says abeam (beside) a known site. The last recourse is to visualize the runway flipped toward you two times. If you use GPS, you should know the point on the airport used as its position and adjust your GPS reading accordingly.

The two-mile base reports can be done much the same as the straight in except for the use of the runway flips. Your entry line should be aimed at a point anywhere from a quarter to a half-mile before the threshold.

There is an instance where the 45 entry and two-mile reports can and do present pilots with illusions that can affect their airport arrivals and landings. A pilot using the 45 entry at a runway of 3000' or less should plan to turn downwind abeam the departure end. Flying to midfield before turning will reduce all the flight segments to 1/4 mile. The best way to see this effect is to compare the pattern of a 5" drawing and a 3 inch drawing of a 45 entry. The best advice I have for flying a pattern at a small or unfamiliar small airport is to keep the downwind twice as far as you think you should and you will be about right.

Where parallel runways exist, any requested departure may be restricted by ATC until they authorize a turn for reasons of conflicting traffic. At any airport, a particular departure may by limited because of terrain, noise abatements, or local considerations where turns are only allowed after reaching a particular point or altitude. Every airport will usually have a place where the preferred or prohibited flight procedures are explained and/or illustrated.

Intersecting runways make possible restricted clearances to land. The restriction most often requires the pilot to land and hold short of the intersecting runway. A pilot should not accept such a clearance unless able to comply.

Air Traffic Control
Control is force-backed illusion. The force of the FAA is politely applied by the controller and by pilots at non-towered
airports. The pilot has an average of 75 hours to learn the control factors at airports. A controller takes two years to be
turned loose. If taxiing is the last flight skill fully acquired by pilots, then radio procedures are the last talking skill awaiting
mastery.

The proper use of the radio allows a pilot to prevent trouble from raising its ugly head and avoids trouble when it affects
your flight path. Proper use of the radio requires both flight and ground awareness of airspace and ground-space. You
can't see the airspace but need to acquire knowledge of it by reference to charts. You can see ground-space by knowing
the signage and line color symbolism painted on the airport. One of the more recent changes is the solid/broken line used
to show movement areas (required communications) and non-movements areas (no required communications).

As a proficient pilot you must be able to use the traffic pattern indicators at an airport to determine the landing runway
indicators as well as the direction to make your turns. This information is available both on charts and by airport overflights. Correct interpretation of the available information is essential to safety. The system is supposed to allow aircraft to arrive
at the airport and enter the pattern in such a way as to avoid conflict with other aircraft. A pilot by using the FAA preferred
arrival and pattern system has no assurance that other pilots are doing the same and therein lies the problem. Not all pilots
follow the suggested pattern and make many 'legal' variations including straight-in arrivals.

The 'legal' though not 'preferred' airport arrivals cause problems for those who fly both the legal and preferred arrival and
pattern. Use of the radio is a preventive but not a 'cure' for such situations. Those who make non-standard arrivals and
patterns are quite likely not to use the radio as well. It is rather contradictory that the FAA should fail to exercise its
control authority over this focal point of aircraft accidents while asserting itself in less contentious places. The conformists
can only be watchful and accept the probable existence of the non-conformists in aviation and at this airport.

You should never accept as gospel what a pilot says about where he is, what he doing and what he is going to do. Leave margins to allow for the unexpected. Standardize your own pattern and approach procedures to the point that you can adjust for the non-preferred activities of another aircraft.

A Pattern to Patterns
The greatest single flying feat that combines all the skills of flying is the airport pattern. Every action is part of a greater plan to avoid and minimize potential difficulties. When an FAA preferred pattern is flown with appropriate radio communication the probabilities of a conflict problem are reduced. The pilot is presumed to have the greatest visual spread toward avoidance of other aircraft as well as physical avoidance.

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Continued on Uncontrolled Airports