U.S. Department

of Transportation

 

Federal Aviation

Administration

 

Air Traffic
Bulletin

 

      
A Communication from the  Director of Air Traffic                        

 

 

Issue # 2003-6

December 2003                                                                                             

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In this Issue:

ADS-B

Phantom TCAS Targets

Aeronautical Information Cutoff Schedule 2004

Terminal Procedures Publication Changes

Bird Activity

Anticipating Separation

Night Emergencies

Radio Communications

Pilot Procedures during Taxi Operations

INCIDENT'LY

Automation, Ergonomics and You

     VFR Judgments

Automatic Dependent  Surveillance-Broadcast (ADS-B)

/F*RTE/ Automatic Dependent Surveillance-Broadcast is a new concept in surveillance technology that is based on Global Positioning System (GPS) data rather than radar-computed positions. Approximately once per second, an   ADS-B equipped aircraft transmits its GPS position and other information such as altitude, velocity, identification, and aircraft category via an approved data link. ADS-B transmitters may also be mounted on vehicles to transmit their GPS position, vehicle identification, speed, etc., or mounted to mark obstructions. 

ADS-B information may be received and used by a wide variety of applications including:

         Aircraft-to-aircraft display of ADS-B equipped aircraft using a new technology referred to as cockpit display of traffic information (CDTI). 

         Airport vehicle displays similar to CDTI that provide equipped vehicles with real time aircraft and vehicle location information.

         Integration into air traffic control (ATC) automation systems, e.g., ASDE-X, Common ARTS, STARS, and Micro EARTS as an additional surveillance source providing improved system accuracy and reliability and also providing surveillance coverage in non-radar areas.

          Airlines can receive real time positional information for their flights and integrate this into a surface management system for improved gate control procedures.

 

 

 

 

Overview of ADS-B Concept

 

The FAA's Safe Flight 21 (SF-21) Program is a cooperative effort between government and industry to develop enhanced air/ground capabilities and improve safety and efficiency based on evolving communications, navigation, and surveillance technologies.

Controllers in the Bethel, Alaska, area of the Anchorage Air Route Traffic Control Center (ARTCC) have been using ADS-B as an approved source of ATC surveillance outside radar coverage since January 1, 2001. The SF-21 Capstone Program has equipped over 200 commercial aircraft in southwest Alaska with ADS-B avionics. Plans are underway to expand the area of ADS-B surveillance coverage to other portions of Alaska and further examine the benefits of this new technology.

Another SF-21 initiative is taking place in the Ohio River Valley. In partnership with United Parcel Service, Inc. (UPS), SF-21 has begun to conduct an evaluation of new ADS-B/CDTI concepts involving the entire fleet of UPS Boeing 757 and 767 aircraft. Because of the higher concentration of ADS-B/ CDTI equipped UPS aircraft, Louisville Standiford Airport was chosen for the in-service evaluation of ADS-B/CDTI.

One of the potential benefits for aircrews having a cockpit traffic display is the shared situational awareness with ATC. The impact to controllers and pilots, along with proposed procedures and phraseology, will be analyzed during the evaluations of this technology. Expanded use of ADS-B/CDTI equipment by the aviation community will be influenced by the safety, capacity, and efficiency benefits that result from the use of the equipment.

Plans are underway for the FAA to expand its ground infrastructure to support the use of ADS-B/ CDTI in other regions, including the east coast and the area around Prescott, Arizona. In addition, Boeing and Airbus are equipping all new aircraft with ADS-B transmit capability increasing the opportunity for ADS-B/CDTI equipped aircraft to see other ADS-B aircraft worldwide.  (ATP-430)

Phantom TCAS Targets

/*TE/ The Los Angeles ARTCC has been experiencing a phenomenon in the Southern California area where aircraft in the high altitude structure report receiving TCAS resolution advisories (RA) when no other traffic is present that would explain the occurrence. The Accident Investigation Division, AAI-100, is leading the effort along with experts from headquarters, region, field offices and civilian and military agencies, who are working on discovering what is causing the phenomenon and thereby how to mitigate its affects.

Controllers and pilots are reminded to remain vigilant and comply with the requirements of the

TCAS RA program. It is all too easy to be complacent and respond slowly or not at all to a situation that may seem to be a false alarm, but bottom line, no one can say quickly whether or not the RA is a bona fide response to a possible conflict or merely a phantom. Please treat all TCAS RA with respect. Do not issue control instructions that are contrary to an RA the pilot has reported. You may provide traffic information as appropriate. Additional guidance is included in FAAO 7110.65, paragraph 2-1-27, TCAS Resolution Advisories. (AAT-200)

Aeronautical Information Cutoff Schedule for the Year 2004 (Leap Year)

/*TEFR/ Strict adherence to specified cutoff dates will ensure that aeronautical information is published on the desired effective date. (ATA-100)

EFFECTIVE DATE

TEXTUAL DP'S INST APPROACH PROC

EN ROUTE MTR PREF RTS ARTCC BND

GRAPHIC DPs STARS

SIAP TRANSMITTAL LETTER

CUTOFF FOR SUBMISSION

.26 MSG (PROP IAP)

NUMBER

DATE

25 Dec 03

16 Oct 03

 24 Nov 03

23 Oct 03

 16 Oct 03

03-25

7 Nov 03

* 22 Jan 04

 13 Nov 03

 22 Dec 03

N/A

N/A

 04-01

 5 Dec 03

 19 Feb 04

 11 Dec 03

 16 Jan 04

 18 Dec 03

 11 Dec 03

 04-03

 2 Jan 04

* 18 Mar 04

 8 Jan 04

 13 Feb 04

N/A

N/A

 04-05

 30 Jan 04

 15 Apr 04

 5 Feb 04

 15 Mar 04

 12 Feb 04

 5 Feb 04

 04-07

 27 Feb 04

* 13 May 04

 4 Mar 04

 12 Apr 04

N/A

N/A

 04-09

 26 Mar 04

 10 Jun 04

 1 Apr 04

 10 May 04

 8 Apr 04

 1 Apr 04

 04-11

 23 Apr 04

* 8 Jul 04

 29 Apr 04

 7 Jun 04

N/A

N/A

 04-13

 21 May 04

 5 Aug 04

 27 May 04

 2 Jul 04

 3 Jun 04

 27 May 04

 04-15

 18 Jun 04

* 2 Sep 04

 24 Jun 04

 2 Aug 04

N/A

N/A

 04-17

 16 Jul 04

 30 Sep 04

 22 Jul 04

 30 Aug 04

 29 Jul 04

 22 Jul 04

 04-19

 13 Aug 04

* 28 Oct 04

 19 Aug 04

 27 Sep 04

N/A

N/A

 04-21

 10 Sep 04

 25 Nov 04

 16 Sep 04

 25 Oct 04

 23 Sep 04

 16 Sep 04

 04-23

 8 Oct 04

* 23 Dec 04

 14 Oct 04

 22 Nov 04

N/A

N/A

 04-25

 5 Nov 04

* Denotes Change Notice (CN). NOTE: There is no CN for Alaskan procedures.

Terminal Procedures Publication Changes

/F*TER/ Effective with the October 30 aeronautical charting cycle, military instrument procedures will be published in the FAA U.S. Terminal Procedures Publication (TPP). This change should present no operational impact unless both military and civil procedures are published for the same airport; e.g. Yuma MCAS/Yuma International, Sheppard AFB/Wichita Falls Muni, etc. Except when a pilot requests it, civil aircraft operating into civil airports should not normally be cleared for military approach procedures. However, civil aircraft may be authorized military procedures at civil airports for training (practice approaches).

When an instrument approach is required, 14 CFR Part 91,175(a) requires, "Unless otherwise authorized by the Administrator, when an instrument letdown to a civil airport is necessary, each person operating an aircraft, except a military aircraft of the United States, shall use a standard instrument approach procedure prescribed for the airport in Part 97 of this chapter." Part 91.175(g) states, "Unless otherwise prescribed by the Administrator, each person operating a civil aircraft under IFR into or out of a military airport shall comply with the instrument approach procedures and the takeoff and landing minimum prescribed by the military authority having jurisdiction of that airport."

Only FAA procedures are Part 97 and the source of instrument procedures is identified in parenthesis at the top center of the procedure chart. Civil procedures that meet Part 97 requirements are identified by "(FAA)". Military procedures do not meet Part 97 requirements and are identified by the applicable military service; e.g. "(USAF)", "(USN)", "(USA)". This does not mean in any way that military instrument procedures are inferior or "less safe" than FAA procedures. Military procedures are developed using FAAO 8260.3, United States Standard for Terminal Instrument Procedures, however, they are not regulated under the 14 CFR Part 97 process (e.g., they are not published in the Federal Register, etc.). (ATP-120)

Bird Activity

/*TER/ In our continuing efforts to reduce aviation accidents and incidents all air traffic personnel must remain diligent in the area of issuing bird advisories to pilots. With our yearly refresher training that addresses the hazards and preventative measures, we want to ensure that all personnel clearly understand their responsibilities in this area.

FAAO 7110.65, paragraph 2-22, Bird Activity Information, directs air traffic personnel to issue advisory information on pilot-reported, tower-observed, or radar-observed and pilot-verified bird activity. Include position, species or size of birds if known, course of flight, and altitude. Do this for at least 15 minutes after receipt of such information from pilots or from adjacent facilities unless visual observation or subsequent reports reveal the activity is no longer a factor. Personnel are also directed to relay bird activity information to adjacent facilities and to flight service stations whenever it appears it will become a factor in their areas.

FAAO 7210.3, Facility Operation and Administration, paragraph 2-1-15, Bird Hazards, directs facility managers to establish procedures that will ensure any bird strikes or trend toward an increase in bird activity on or around the airport served by the airport traffic control tower are reported to airport management. Airport management is responsible for the issuance of NOTAMs when flocks of birds roost on the runways.

Industry receives information on bird hazards through the Aeronautical Information Manual,  Chapter 7, Section 4, Bird Hazards and Flight Over National Refuges, Parks, and Forests, and through the Aeronautical Information Publication, Section ENR 5.6, Bird Migration and Areas With Sensitive Fauna. Air traffic controllers are encouraged to review this information.

Keeping all parties involved and informed will help facilitate safer aerodromes, timely reporting, and less structural damage. (ATP-100)

Anticipating Separation 

(This article first appeared in the Fall 2000 issue of the Air Traffic Bulletin)

/*T/ FAAO 7110.65, paragraphs 3-9-5 and 3-10-6, provide for the application of anticipated separation for departures and arrivals. A takeoff or landing clearance need not be withheld if the prescribed runway separation will exist when a departing aircraft starts its takeoff roll or when an arriving aircraft crosses the landing threshold. The determination that prescribed runway separation will exist is based on positive control through the issuance of specific instructions to ensure that crossing traffic or other aircraft will not be factors for the landing or departing aircraft.

In correctly applying anticipated separation, a controller must recognize that pilots are listening on the frequency and may try to second-guess the controller's intentions if the intentions are not clearly specified. In a recent incident, a controller had assumed that an arriving aircraft landing on a crossing runway would roll through the intersection prior to the time that the departing aircraft on the crossing runway began its takeoff roll. No instruct-ions were issued to the landing aircraft to proceed through the intersection or to turn off the runway at any particular exit. As a result, the pilot of the landing aircraft, upon hearing the issuance of the takeoff clearance to the departing aircraft, applied heavy braking and tried, unsuccessfully, to stop short of the intersection.

It must be emphasized that the above example constitutes an inappropriate and incorrect application of anticipated separation. Action was not taken to ensure that the aircraft would roll through the intersection prior to the time that the departing aircraft began its takeoff roll or exited the runway at a specified point prior to reaching the intersection. A correct application of anticipated separation is predicated on the issuance of specific instructions with acknowledgements, if appropriate, so that the controller can ensure that all potential conflicts will be resolved and that all pilots understand and have acknowledged their instructions.

As the example highlights, basing separation on assumed actions of pilots may lead to undesirable results. In conclusion, anticipating separation is not assuming that separation will exist; anticipating separation is exercising positive control actions to ensure that the prescribed separation will exist. (ATP-120)

Night Emergencies

/*TER/ One of a pilot's greatest concerns about flying a single-engine airplane at night is the possibility of a complete engine failure and the subsequent emergency landing. Even though flight into adverse weather and poor pilot judgment account for most serious accidents, night emergencies are always very serious events. Controllers should be aware of important pilot procedures and considerations for dealing with night engine failure and other similar emergencies.

When advised of a night engine failure, controllers should be aware that pilots must maintain positive control of the airplane. Pilots should establish the best glide configuration and airspeed. Controllers can sometimes assist the pilot in turning toward an airport, away from congested areas or away from mountainous terrain. Surface wind direction and speed information is important to a power-off aircraft landing at night since a downwind landing should be avoided.

Controllers should obtain enough information to handle the emergency while the aircraft is still in radio and radar contact. Remember, the pilot is authorized by 14 CFR Part 91 to determine a course of action but controllers can get help on the way before the landing is completed. Sometimes pilots will communicate with ATC after an emergency landing, however the Airplane Flying Handbook recommends that the pilot turn off all switches and evacuate the aircraft as quickly as possible.

Finally, FAAO 7110.65 reminds controllers, "because of the infinite variety of possible emergency situations, specific procedures cannot be prescribed. However, when you believe an emergency exists or is imminent, select and pursue a course of action which appears to be most appropriate under the circumstances and which most nearly conforms to the instructions in this manual." (ATP-120)

Radio Communications

/*TER/ Radio communications are a critical link in the ATC system. The link can be a strong bond between pilot and controller or it can be broken with disastrous results. FAAO 7110.65 provides standard ATC phraseology for providing ATC services. Good communications or phraseology enhances safety. Therefore, we encourage controllers to speak at a reasonable rate and to use standard phraseology when communicating with all flight crews, especially those whose primary language is not English. (ATP-120)

Pilot Procedures During Taxi Operations

/*T/ FAA Flight Standards Service (AFS) recently revised two Advisory Circulars (AC) pertaining to pilot procedures during taxi operations. The AC numbers are AC 91-73A, Part 91 and Part 135, entitled Single-Pilot Procedures During Taxi Operations and AC 120-74A, Parts 91, 121, 125, and 135 entitled Flightcrew Procedures During Taxi Operations. Both ACs are dated 9/26/03 and are located at:  http://www.faa.gov/regulations/guidance.cfm"

The purpose of the ACs is to provide guidelines for the development and implementation of standard operating procedures for conducting safe operations during taxiing. The ACs are intended for use by pilots. However, controllers are encouraged to review these ACs to enhance awareness and to strengthen the controller-pilot communications link. Below are just a few of the revisions to AC 120-74A. Similar revisions are also contained in AC 91-73A.

Paragraph 6c (2) (c), pages 5-6.

Flightcrews should be especially vigilant when instructed to taxi into "position and hold," particularly at night or during periods of reduced visibility. They should scan the full length of the runway and scan for aircraft on final approach or landing roll out when taxiing onto a runway either at the end of the runway or at an intersection. ATC should be contacted any time there is a concern about a potential conflict.

In instances where flightcrews have been instructed to taxi into "position and hold" and have been advised of a reason/condition (wake turbulence, traffic on an intersecting runway, etc.) or the reason/condition is clearly visible (another aircraft that has landed on or is taking off on the same runway), and the reason/condition is satisfied, they should expect an imminent takeoff clearance, unless advised of a delay.

If landing traffic is a factor, the tower is required to inform flightcrews when clearing them to taxi into "position and hold" of the closest traffic that is cleared to land, touch-and-go, stop-and-go, or unrestricted low approach on the same runway. Flightcrews should take care to note the position of that traffic and be especially aware of the elapsed time from the "position and hold" clearance while waiting for the takeoff clearance.

ATC should advise flightcrews of any delay in receiving their takeoff clearance (e.g., "expect delay for wake turbulence") while holding in position. If a takeoff clearance is not received within a reasonable time after clearance to "position and hold," ATC should be contacted. Suggested phraseology: (call sign) holding in position (runway designator or intersection). Example, "American 234 holding in position runway 24L," or "American 234 holding in position runway24L at Bravo."

Paragraph 6f (5) (a) (b), page 9.

Flightcrews should read back all clearances/ instructions to enter a specific runway, hold short of a runway, and taxi into "position and hold," including the runway designator. Pilots should not merely acknowledge the ATC instruct-ions or clearances to enter a specific runway, hold short of a runway, and taxi into "position and hold" by using their call sign and saying "Roger" or "Wilco." Instead they should read back the entire instruction/clearance including the runway desig-nator. Air traffic controllers are required to obtain from the pilot a readback of all runway hold short instructions. (FAAO 7110.65 paragraph 3-7-2d.)

Paragraph 8b (4) (5), pages 14 15.

When entering a runway either for takeoff or when taxiing into "position and hold," flightcrews should make their aircraft more conspicuous to aircraft on final behind them and to ATC by turning on lights (except for landing lights) that highlight the aircraft's silhouette. Strobe lights should not be illuminated if they will adversely affect the vision of other pilots.

Additionally pilots are advised to turn on landing lights when takeoff clearance is received, or when commencing takeoff roll at an airport without an operating control tower. (ATP-120)

INCIDENT'LY

Automation, Ergonomics and You

         Automation: Automatically controlled operation of an apparatus, process, or system by mechanical or electronic devices that take the place of human organs of observation, effort, and decision.

         Ergonomics: An applied science concerned with the characteristics of people that need to be considered in designing and arranging things that they use in order that people and things will interact most effectively and safely.

In the past 10 years or so, controllers have seen an increase in new equipment introduced into their facilities. The equipment provides more information to controllers, automates some functions, and presumably, overall makes the controller's job easier. When new equipment arrives, the old equipment and ways of operation are often discarded as "antiquated" or no longer necessary. In many cases this is true, however, in some cases the total replacement of an old, hallowed way of doing business or piece of equipment may not help everyone as much as the designers or the facility had expected.

As is the case with clothing styles, cars and the like, one size does not always fit all.

For example, DSR and STARS equipment have many automated functions. Information can be acquired by a single or series of key strokes or the use of the mouse/slewball. For some people, this method of access works like a charm and seems quite natural, but for others, it could be a distraction when compared to the "old way" of accessing the information. For example, a single glance at a paper flight progress strip, or "cheat sheet" posted at the position as compared to accessing a computer
pull-down box to display the wanted information might seem easier to some people, yet annoying to others.

If you have a choice, obviously, you will use the method that is most beneficial to your style of work. Matching styles of work with the equipment can help to avoid mistakes. An example of such ergonomics might be the simple design where an aircraft's mixture control knob is knurled and red in color and the throttle is smooth, somewhat larger and black in color. This helps the pilot identify the correct knob by both the sense of touch and sight.

You can probably come up with other better examples where equipment has been designed to better fit the person using it so that no injury results in using it, it is intuitive or natural to use, or again, its use is better protected against inadvertent application. Another example might be whether a work station can be set up for right- or left-handed persons. It is to your advantage to recognize and use the tools and methods that best suit you.

Of course, when new systems replace old ones, the option of continuing to use what worked well for you in the past may be severely limited. So, what can you do? Probably, the best option may be to become as proficient as possible using the new system. Now you might think, "Oh, that's so obvious it's stupid of the writer to mention it!"

You have to wonder though, could the reason some individuals are surprised by an aircraft's "sudden" turn at a point on its route be because the individual doesn't know that the aircraft will change direction at that point? Could the reason that the individual does not know this will happen be due to a reluctance to use the equipment options because of a lack of comfort, knowledge, or expertise in using the equipment? If this is the case, then the individual will prefer to work "in the dark," banking on his/her ability to keep track of the traffic by solely scanning the scope. By choosing this method, the individual may feel that he/she will not incur the stress or worry of getting behind or disrupting his/her concentration by trying to make various fancy computer entries. The "in the dark" methodology is probably more prevalent than you may think. Bottom line, it doesn't always work well.

Here we might take a lesson from our piloting friends. Pilots learn to deal with certain emergencies and procedures by employing a learning technique called, "over learning." That is, they practice the sequence of movements in the cockpit so frequently that they become totally automatic. This means that when a certain situation occurs, the subsequent actions are accomplished quickly and accurately without conscious thought. The concept of over learning can easily be demonstrated by learning to drive a stick shift automobile. When first attempted, the driver has to concentrate to get the sequence of clutch, shift, and power worked out. Once learned, however, the driver no longer needs to give the action any more thought than I want to go, or slow, or stop. Period. Once the over learning process has been completed, the driver may be asked to give directions to the post office or name the moons of Jupiter, and although much thought may go into naming the moons, no thought will be wasted on shifting the car's gears . . . that will happen effortlessly.

Many of the controller errors that seem inexplicable may be due, in part, to too much conscious thought having to be devoted to certain actions. For example, a very experienced controller climbs or descends an aircraft right through another that is within 10 miles on converging courses, having completely overlooked that aircraft, or failed to realize that it will change its course at the next intersection or NAVAID and it will become a threat to another aircraft. If your short-term memory is full of bits of information or actions/thoughts that could be relegated to the over learning process, you are likely experiencing a temporary short-term memory overload, and yes, you forget stuff. The more actions that you can commit to long-term memory where the over learning is maintained, the better off you will be in heading off short-term memory overload. This is where your ability to quickly access information through your position's automation without a lot of conscious thought is to your advantage.

Aside from over learning, there may be additional ways to enhance your ability to keep track of your position's demands. For some, it could be as simple as a pad of paper and a pen or pencil for short, cryptic notes that help you avoid silly mistakes due to faulty recall or inadvertent forgetfulness. It should go without saying that any visual memory joggers or tools that you employ must be scanned (glanced at and read) frequently to refresh your short-term memory. That is what such tools are designed to do. Other techniques are the particular physical placement of a flight progress strip holder. Think about it and see if there might be ways to enhance your ability to do your job and make the most of the equipment you have to help you do it. Think about your own ergonomic design needs and how you can best enhance your working relation-ship with the automation in your life.

Visual Flight Rules (VFR) Judgments

The VFR tower controller's area of major responsibility is generally defined by whether or not standard separation is maintained on the runway surface environment. Obviously, if the standard is not maintained, an incident or accident will be the result. The FAAO 7110.65 states that the "primary purpose of the ATC system is to prevent a collision between aircraft operating in the system and to organize and expedite the flow of traffic." To that end, numerous tools and procedures have been developed and controllers trained to use them to provide good, safe service.

Each facility has its responsibilities defined as to what and where separation must be assured. Except in certain circumstances, most airborne aircraft will be provided some form of separation services in the form of a separation standard that the controller is required to provide. However, the VFR tower controller is taxed with providing separation primarily in and around the runway environment. Since the primary purpose of ATC is to prevent collisions in the system, how does the lack of a "standard separation" in the traffic pattern square with the primary purpose?

The term, VFR tower, helps explain this. Pilots are required to use visual flight rules when flying in the Class D airspace and subsequently, in the airport traffic pattern. Those large windows in the VFR tower building give the control specialist a good viewing platform from which to oversee the pilots. Traffic advisories, safety alerts, and some control instructions are all methods that the controller can use to help the pilot maintain safe operations and thereby prevent collisions. The following are a few tips and techniques that can help a controller be more effective in achieving both goals. Please note that a BRITE radar is not necessary to be successful. It is a tool that is helpful for telling a controller what direction and range to expect when beginning the visual search for the aircraft through the tower windows.

Rule of Thumb:

         Locate the aircraft visually (out the window) as soon as possible and as far away from the airport as possible. This is always to your advantage.

         If available, use the BRITE to show you in what direction to look and what range, then . . .  

         Locate the aircraft by looking out the window using . . . the naked eye AND the binoculars.

 

Techniques for visually sighting aircraft:

         Based upon the pilot's position report, consciously look long range, mid range, or short range. Do not just look out of the window. Your eyes will not focus to a long range without conscious effort but more to a medium-short range, which will not be effective.

         If the aircraft is 5 miles or more away, start at the horizon and work your way from left to right or vice versa, including an upward scan block by block in a grid pattern, slowly. Be sure to stop your eye movement and peer straight ahead momentarily before continuing your scan at frequent intervals. This is very useful for detecting movement. What you are looking for is a speck moving across your field of vision. When you sense movement, focus on it to determine whether or not it is your aircraft. If a bird has caught your attention due to its movement, then you know that you have been focusing in too close. If the squashed fly on the window shade catches your attention, you are really focusing too close! In both cases, adjust your focus accordingly.

         If the aircraft is closer than 5 miles you should begin your search slightly higher above the horizon. NOTE: If the aircraft is closer than 5 miles, begin your search much more above the horizon. If the aircraft is 3 miles or closer, begin your search at the runway threshold and work your way outward. Always think about searching the area nearest the threat area. The threat area could be another aircraft's flight path or the runway. The closer an aircraft is to you, the higher in the sky it will appear EXCEPT for aircraft on short final, flying a low, flat approach. A good technique to help train your eye is to search for aircraft that report at a known distance. For example, the final approach fix for an instrument approach will have the aircraft at a specific altitude and range, which is ideal for practice. If an aircraft has distance measuring equipment (DME) and so does your localizer or VHF omni-directional radio range (VOR), you can ask the pilot to report the aircraft's DME position and then remark to yourself what the aircraft looks like at that distance and altitude. Practice finding it with the binoculars and then your naked eye.

         Once the skill of accurately adjusting your vision to near, medium, and far is mastered, you will be able to adjust it rapidly as you scan. You should be able to do this with the binoculars alone as well as only your naked eye.

         When the aircraft is sighted through binoculars, find it with the naked eye by moving the glasses downward from the aircraft to the horizon. Remove the glasses and, using the horizon or object on the horizon (water tank, building, tree, etc.) as a guide, move upward to attempt sighting the aircraft. Take care that you maintain the same focus for the distance to find the aircraft. If you cannot see the aircraft with your naked eye, come back with the binoculars a little later and repeat the exercise.

         Sighting aircraft may be enhanced if you know ahead of time what to expect it will look like. An aircraft's appearance will depend upon the lighting conditions and sky background. Sometimes aircraft will appear white, silver, black, or grey at a distance. Learn which color should be expected with each meteorological condition. This will help you find aircraft at a further distance from the airport.

         The longer you have to observe an aircraft, the better you will be able to judge its speed and how and where it will enter your pattern. This information will assist you in judging its sequence with other aircraft as well as determining what traffic information will be useful to the pilot for collision avoidance.

         A busy local controller will often work aircraft with the binoculars and pencil in one hand and the mike switch in the other, or frequently pick up the binoculars throughout the session.

         Be careful not to use the binoculars exclusively, because they narrow your line of sight and do not have the greater peripheral vision that your naked eye has. Use them a lot, but you will need your unencumbered eyes to keep track of aircraft on the runway and taxiways and in the traffic pattern.

Note: The distances of 5- and 3-mile guidelines are approximate. Generally, the further away an aircraft is, the lower is will appear on the horizon. Conversely, the closer it is, the higher it will appear. (AAT-200)

 

 

 

 


Questions/comments about content should be addressed to ATP-100