Contents:
Air Traffic Control (ATC); ...The System; ...Tower Operations; ...Class C and B Airspace; ...Terminal Area;
...Air Route traffic Control Centers; ...Radar Identification; ...FSS Procedures; ...Flight Watch;
...Pilot Arrival Operations; ...Pilot Departure Operatons; ...Travis Airspace;
Air Traffic Control (ATC)
The primary purpose of ATC is the give safe separation between aircraft. This includes airports, enroute, and flight information. The secondary interest is the movement of aircraft. When no other aircraft is in conflict the pilot is in charge. When aircraft conflict in controlled airspace then the conflict and movement becomes a shared responsibility that can be shifted between ATC and the pilot. for example, when ATC points out traffic, the traffic is an ATC responsibility until the pilot acknowledges having the traffic in sight. At that point and until the pilot tells ATC that the traffic is no longer in sight, the traffic remains a pilot responsibility. There may be times when it is to the pilot's advantage "not to see' traffic and to report losing traffic that was once acknowledged as being seen.
In the moving of aircraft, the limiting factor has become not airspace but runway. Airports are two-ended funnels with arriving and departing aircraft focused at each end of the runway. There are limits to what ATC can see and do. It, behooves the pilot to be sensitive to these limits and fly his arrivals and departures to give maximum assistance to ATC while retaining his PIC responsibility to avoid conflicts while expediting movement. The pilot must retain situational awareness of other aircraft both as to position and movement.
All aircraft movements cannot maintain maximum efficiency. There will be delays and waits that are 'safety margins' built into the system. Plan for and expect that your arrival or departure will not be ideal. Do not try to change things that cannot be changed. If your situation becomes critical, declare an emergency sooner rather than later. You are far more likely to hear from the FAA for a failure to declare than you are for declaring.
As with other situations aircraft communications exchanges information through symbols, signs, words and behavior. Very often this communication is imperfect, resulting in erroneous information transfer. there are many causes for error but the most common is incorrect reference. The sender and receiver must be on the same channel to exchange message and feedback.
The student should make a point to visit a local ATC facility such as a tower to learn to put faces with the voices. Some pilots buy radios to listen to at home or in the car. This would be very good, if it were not for the fact that 80% of the General Aviation radio procedures leave much to be desired. Most pilots are not aware of the extent to which the ATC controller patiently compensates for pilot incompetence. Very often the delay in an ATC response is because the controller finds it necessary to sort out what was said and put it into understandable form. The radio identification of a pilot as a student pilot is essential since it allows the controller to be aware and anticipate problems caused by inexperience. On the other hand, the certified pilot is expected to be both competent on the radio and in the air.
Tower controllers, air and ground, are on constant listening watch for relatively long periods of time. Up to two hours. Their brains are turned on when the tower name is said. If you keep saying the tower name after the first contact it only causes confusion. They may write the aircraft call number and expected entry while they issue a clearance. This is a three dimensional chess game with different types of aircraft coming from different directions to different runways at differing speeds. They are good at what they do but the pilot must be knowledgeable as well. Tower controllers will usually clear you for the most economical arrival traffic conditions permitting. Tower communications should always be a concise expression of required information. By including your altitude you provide other aircraft with additional collusion avoidance information.
Professional pilots use the specifically appropriate procedure. It is difficult to accept that over 90% of all ATC radio communications is "canned". There is a standard format of what the pilot should say, a preferred place to say it, a standardized sequence, and a required ATC response. Most ATC communications are "canned" instructions delivered in a predicable highly formatted manner. Once understood these instructions are easy to prepare an answer or possible answers ahead of time. By including ATC requirements in your callup you can anticipate your instructions and get the golden ring as, "Approved as requested".
A 'clearance' is a kind of verbal contract between sender (ATC) and receiver (pilot). The feedback must be accurate so the 'hearback' can be assured of reception. Any error is a potential disaster.
The use of correct 'standard' communications procedure with ATC makes for cleaner more professional operations with less chance of misunderstanding. Think of what you expect the controller to say and incorporate it as a 'request' or advisory. ALL radar facility communications to you are repeated back again in your response in as complete a format as you are able. With experience some abbreviation is permissible. Safety in today's airspace requires mutual understanding and trust. More often than not the operation of the ATC system (not the controllers) is done for the convenience of the system rather than for the convenience of the pilots or their aircraft.
Listen to ATC communications to improve your situational awareness and minimize unnecessary communications. With experience you will be able to anticipate how you can help ATC such as by requesting a different runway or departure. Become sensitive to how busy the controller is and adjust your procedure accordingly. If the controller is obviously busy don't bother with making a request...do that later. If the controller does not give you time to acknowledge...don't. If you are given a command EXECUTE and then use the radio. If you don't understand all or any part of what is said, have them "say again" or "say again all after...".
As a driver, you are familiar with defensive driving. You must fly defensively as well. Never assume that another aircraft is going to maneuver in a given direction or follow a particular ATC directive. On the other hand, you should follow ATC directions. If you don't understand the directions, say so. Don't taxi from your tie-down without knowing where you are going and how you are going to get there. If any doubt exists, get ATC assistance.
Flying in controlled airspace is a partnership, really a limited partnership, where responsibility, control, and liability is constantly shifting back and forth. Your position as a pilot in command depends on your understanding of how, when and where any shifting occurs. ATC is primarily concerned in aircraft separation. Regardless of the congestion, a controller cannot reduce separation unless a pilot declars an emergency. An emergency allows a pilot or controller to deviate from minimum separation rules or any other rules.
ATC will shift full separation responsibility to the pilot at every opportunity. A recent FAA interpretation says that a pilot is responsible for any clearance given by ATC whether or not it is heard, misunderstood, misinterpreted, readback, or mis-readback.
One of the ways that ATC can shift the entire load to the pilot is by prompting him to acknowledge having an aircraft in sight. ATC can 'point-out' traffic and prompt you to 'report traffic in sight'. Once you have reported the traffic as being in sight you are responsible for separation. However, you can shift responsibility back to ATC just by saying you have lost sight of the traffic.
Crowded Skies
By the mid 1970 the word was:
--The ATC system is subject to frequent flight delay
--Numerous disturbing aircraft to aircraft incidents.
--We are running out of sky room.
--Inability to maintain a high standard of safety.
Solutions
--1978 a comprehensive plan for modernizing and improving ATC and airway facilities by 2000.
--Reduce radio transmissions.
--Electronic assistance
--Shared responsibility
The New ATC
Open architecture of both hardware and software is the plan to ensure that never again will total obsolescence occur in the
ATC system. The ideal is to have 12-year procurement and 25-year life in an age where the life expectancy of a top level
device and system is measured in months. The upgrades are planed around Commercial Off The Shelf (COTS) computers
and software. 1/7 of the total cost of STARS is in hardware of a billion-dollar investment. The problem is that by the time
the hardware installation is completed the equipment is already out of date. By having a standard operating system it is
hoped that a mix of old and new can be achieved in an ongoing manner. There will be no unique interfaces incorporated in
any of the new upgrades.
One aspect of STARS is the passive final approach spacing tool (pFAST). This integrates surveillance data, flight plan data,
aircraft performance characteristics and airway procedures into a central database. This will allow the ATC controller to
use real time information to refine spacing and sequence. It is expected that this along with a similar program for enroute
aircraft will increase both airway and runway capacity.
An additional radio program is designed around the VHF Digital Link (VDL) Mode 3 which will allow four voice and
simultaneous data channels where only one voice channel exists at the present. The ADS-B system will give pilots the
same situational awareness as enjoyed by ATC. This change has been traditionally fought by the FAA/ATC bureaucracy
that is now overwhelmed by the sheer numbers of aircraft trying to occupy ever smaller space.
The System:
The FAA-ATC radio system has several types of facilities that require subtle differences in use of the radio. Radio procedures are different for tower controlled airports than for other ATC facilities. There are even selective differences between similar airports due to historic preferences or operational requirements. The better you understand why they do what they do the better you will understand the importance of correct radio procedures.
Tower Operations:
The tower controller is known as local control. He is responsible for the active runways, inbound and outbound traffic inside the airport airspace. Ground control is responsible for all airport movement area traffic. This includes cars, trucks, and airplanes on taxiways, some ramps, and inactive runways. Ground coordinates the crossing of active runways with the local controller. The flight data position does such things as getting IFR clearances, making the ATIS, and coordination with approach control. At some airports in very light traffic conditions one person may work all positions.
A supervisor is in watchful command of the total shift operation. He has great flexibility in rotating the positions to maintain efficiency. Each controller goes though initial training in Oklahoma City. He then works in the facility at each position until certified in that position. The local controller (tower) is playing three-dimensional chess with aircraft of different categories and types. These planes are arriving from different direction, at different speeds, with varying levels of pilot competence. The ATC mandate is to provide safe, orderly, and expeditious movement of traffic. Pilot competence is vital if ATC is to do its job well. The first clue the controller has of pilot competence is the way the radio is used by the pilot. The best way to learn how the system works is to make a practice of visiting towers at every opportunity. When you know what the controllers are doing and why, you can use both the radio and the flight path to make things work better.
Class C and B Airspace
Over 100 U. S cities have a magenta area designated as Class C airspace. Radar service is available but not mandatory. You must establish contact and maintain a listening watch but you can refuse the service. (not smart). Major cities have Class B airspace. Students are not allowed into Class B airspace without an instructors endorsement as to training and proficiency.
An flight entering a radar service area requires that the pilot plan for the communications involved. Get any required ATIS before making contact with approach. Know exactly where you are going to be before making contact. You can be violated by the FAA for an accidental entry into both Class C and B airspace. The pilot is responsible for the 'see and avoid' mandate and should not place undue reliance on radar advisories.
A radar target not in ATC contact has altitude that is only 'indicated' not confirmed. Traffic advisories are a part of radar services which includes weather advisories, terrain, obstruction, and low altitude alerts. Should you ask for flight following instead of traffic advisories you may not get the rest of the services. It is better and wiser to get all the help you can. Advisory service is available to VFR pilots only when the workload permits.
Terminal Area (TRACON)
Basic separation within 40 miles of single antenna is three miles in airport/terminal airspace. IFR/VFR separation is 1.5-miles in Class B. Beyond 40 miles of antenna it is 5 miles.
The pilot should know that under VFR conditions once you have told ATC that you have visual contact with traffic you may not receive any further radar advisories on that traffic. They may not advise you again of altitude or direction. It is up to you to evade any possible wake turbulence. ATC will let you fly right under a DC-10' wake turbulence and not issue a warning. You must be aware of this lack of protection and be assertive enough to make a 360 or whatever it takes for avoidance. It may be best not to 'see' traffic
Air Route Traffic Control Centers (ARTCC)
5 miles is the minimum for IFR. Several antenna returns are displayed as one. Center antennae are connected by land line radio systems and parabolic relays spaced about 17 miles apart. ZOA, which is Oakland center, covers an area from the middle of Nevada down to Bakersfield, along the coastal waters of California up to the Oregon Border.
Center operations are separated from TRACON services by distance and altitude. Center services will not be made available unless you have sufficient altitude to give both a radar return and radio communications.
Radar Identification
--Contact and identity established by 1-mile or runway is 'contact".
--Radar return at specific reported position is 'contact'.
--Radar vectors may be used to identify and establish 'contact'
--Transponder codes are used. Mode C gives altitude that must be validated by each successive controller.
Data Block
The computerized radar is capable of showing the aircraft route, a conflict with another aircraft, range and bearing from any fix, and a minimum safe altitude warning.
FSS Procedures
The FSS may have up to 12 radios operating from one switch panel. It is necessary for the pilot to know the differing dedicated frequencies and how to obtain them. The emergency 121.5 and FSS universal 122.2 frequencies do not usually appear on charts or other sources. You, the pilot, are expected to know that these are common to Flight Service Stations. If a frequency for an FSS is followed by an R, it means that the FSS can only receive; if a frequency is followed by a T, it means that the FSS can only transmit on that frequency. Since some of the frequencies may be far beyond the line of sight requirement it is important to be careful in making your frequency selection.
Failure to mention the frequency you are listening on may require an additional callup. You always save time in communications by doing it right the first time. Your initial communication should include the words, "………listening on (Frequency)". You can improve your FSS communications comfort level by making PIREPS when making local flights. The FSS can offer complete weather service, frequencies, airport information, navigational assistance and emergency assistance. Except for the callup, other communications can be conversational.
Some FSS operations are now only part-time. Do not try to stretch radio range. Use nearest available frequency. Know how to select the appropriate FSS frequency, how to use it correctly and when to use it. Some FSS operation is only part-time. The FAA is in the process of making most FSS operations via remote facilities. Oakland and Rancho will service most of Northern California as the smaller stations are phased out. Reference the AIM Chapter 4-92, 5-81, 70-50/58.
Flight Watch
Sitting very near the FSS radio specialists is the Flight Watch radio specialist. His duties extend from 6 a.m. to 10 p.m. local times. This is a nationwide weather information service operating on 122.0. The first Flight Watch station was activated at Oakland about twenty years ago. Since this is the only frequency he may have up to eight remote locations. Oakland has one at Reno, Red Bluff, Oakland, Big Sur, Sacramento, Fresno, and Ferndale near Eureka. There are three HiWAS frequencies for the airlines. Any aircraft over 5000' should be able to contact Flight Watch.
Pilot Arrival Operations
If you are a passive pilot who lets ATC make all your arrival decisions you can just follow orders. This works best if you are quite familiar with the airport and its procedures. At unfamiliar fields you need to work out an arrival with ATC. The easiest, but less efficient way is to request to overfly the field and let them work you into the pattern. Passive radio operations usually require multiple transmissions involving questions and answers. One incompetent pilot with poor radios can tie up the system.
Every light aircraft pilot should be wearing a headset. He should know that microphones are noise canceling. The closer to the mouth the mike the less extraneous noise will intrude. As a pilot you will speak at a measured pace without punctuation. Make no pauses for periods, commas, or thinking. As a student you always let ATC know that you are a student as part of your full aircraft identification so that they can keep an eye on you. ATC communications are practically the same in similar situations. With experience you can recognize the 'canned' aspects and include them in your call-up. The more assertive pilot will take charge of the situation as suggested below. Do all your planning and thinking before you key the mike.
Several planning steps should precede the call-up to a tower-controlled airport. You should get the ATIS well away from the airport. This means you will know the direction of the preferred runway. You will know if a substantial crosswind is involved. You will listen and orient other traffic with reference to your arrival. You will plan your arrival so as to make your initial call-up at a selected reference point and altitude. Reference points are best when they are specific identifiable spot locations. Altitudes below 3000 feet AGL are safest when not at even thousands or five hundreds.
As a student you would be well advised to write your expected arrival out without any shortcuts. Have it so you can read it off. After doing this a few times the writing will no longer be required. Where multiple runways exist some variations are to be expected. With the planning taken care of, you take a deep breath and practice getting everything out in one smoothly paced flow. While you are practicing you will be listening to the radio for ATC references to both inbound and outbound traffic.
Ready begin:
"Podunk tower (Cessna 1234X)(reference point)(at altitude)(with ATIS)(arrival path)(will report) (looking for traffic)". You win if the tower says, "34X approved as requested."
Properly presented and arranged radio work by the pilot helps the controller sort out the factors of aircraft type, position altitude, intentions, and expected report. Making it easy for ATC lets them make it easy for you.
Pilot Departure Operations:
The tower airport departure is a multi step procedure. First you get the ATIS and talk to clearance delivery if radar is involved. This will involve a transponder squawk, departure route, approach frequency and a read back. Plan your call-up to ground just as you would to tower. If you are uncertain or become uncertain don't hesitate to advise ATC and get assistance as you taxi. ATC can see the airport much better from the tower than you can from the ground. On completion of your runup you will contact the local control (tower).
You have looked in the direction you expect to depart before getting into the aircraft. On getting the ATIS you have planned your runway request for the most efficient departure. If you do not get the most efficient departure runway then you must plan your flight departure to establish the easiest interception of the planned route. All too few pilots request the 270 departure that crosses them over the airport on a course that corresponds to the line drew on the sectional. Why begin a flight two miles off course if you don't need to? To help ATC you have named a specific destination rather than a general direction or departure. This provides safer traffic avoidance. A good departure call would be:
"Podunk tower Cessna 1234X student pilot ready (runway number)(right 270 on course Xandu)(have any reported traffic)"
ATC is required to 'point out' any known traffic that may affect your arrival or departure. You should acknowledge that you are looking and when seen you are expected to report 'traffic in sight'. Any time you report having reported traffic you make a friend of ATC since you then assume traffic avoidance responsibility. If after thirty seconds or so you have no visual contact be sure to advise ATC.
Travis Airspace
Travis Approach facility has given two seminars in the last two weeks about the operations, hazards, limitations, use and misuse of its services as offered to General Aviation.
Using a San Francisco Sectional, the Travis radar area is uncharted on the but extends along a line extending northward from four nautical miles west of SABLO intersection through the middle of Lake Berryessa. This is a line that parallels V-195 but four nautical miles to the west. It starts near where V-195 intersects the northern line of the S.F. Class B and extends to the compass rose of the Williams VOR. The northern top extends below the Williams VOR compass rose at right angle across I-5 to intersect a line extending from COUPS intersection on V-6 south of Sacramento Executive northwestward though Davis and Woodland From COUPS the area zigs and zags down to OAKEY intersection on V-108 and covers an area parallel to but four south of V-108 over to reach V-195. A dip in the line extends in a two mile arc below CCR.
The area southeast of Travis radar area is controlled by Stockton Approach. To the south lies Bay Approach, To the west and north Oakland Center reigns. The eastern side borders on Sacramento Approach. Travis radar where not affected by terrain interference controls from the surface to 10,000.
Inside of the radar area is the Alert Area that is charted as Alert Area A-682. Travis has several different patterns for its dual runways. There are IFR, VFR, Radar, and Overhead approaches. Altitudes vary from 2000 to 4000 and very often extend beyond the published A-682 boundaries. This is a radar vector approach that goes directly over Rio Vista at 2000 at all hours. There are MARSA departures in which KC-10s depart at one minute intervals to fly a formation flight at staggered 1000 foot altitudes. Such a departure at speeds up to 250 knots does not give civil aircraft much safe space to operate. Avoid a flight path that conflicts with a MARSA formation.
Military aircraft use a climb to avoid collision. Since any flight below a heavy military aircraft will have wake turbulence below of sufficient power to disintegrate a G.A. plane, it would seem that a turn to avoid under-flying would be the advisable avoidance procedure.
Travis has two basic frequencies, 126.6 to the North and 119.9 to the South. During low traffic periods only 119.9 will be used for the whole area. Military flights that overfly Rio Vista will make their presence known on 122.8. I would suggest users of Rio Vista to use alternative arrival procedures that preclude the use of 2000'.
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