Appendix A A-4 Figure A-1. TCAS II/Transponder Control Panel (Example)
Table A- 1. TCAS II/Transponder Function Selector TEST Holding the TCAS II/Transponder function selector in TEST for 2 to 3 seconds will activate the system test sequence. In the TEST position, read maintenance messages on the display. Use discretion when selecting TEST in flight, since this inhibits both TCAS II and the transponder for approximately 20 seconds. The function selector is spring loaded to STBY.
STBY Activates TCAS II and XPDR warmup cycles.
XPDR Transponder is on. TCAS II is in warmup cycle.
TA Transponder is on. Only the “Traffic Advisory”, or “TA” function of the TCAS II is on. You will not receive any “Resolution Advisories” in this position. The written warning “TA ONLY” will appear on the display, and the yellow “RA OFF” flag will be in view on both IVSIs.
TA/RA Transponder is on. All TCAS II functions are on. No TCAS II flags should be present on either IVSI.
XPDR Fail Light (Amber) Indicates a transponder system failure when the transponder is on.
Comes on during “TEST”, but goes off after approximately 3 seconds if the transponder is OK.
Code Indicator Indicates code selected with the code selectors.
IDENT Causes the word IDENT to flash in the aircraft data block on the ATC display.
ALT RPTG Provides automatic altitude reporting to ATC.
Appendix A A-5 TEST Holding the TCAS II/Transponder function selector in TEST for 2 to 3 seconds will activate the system test sequence. In the TEST position, read maintenance messages on the display. Use discretion when selecting TEST in flight, since this inhibits both TCAS II and the transponder for approximately 20 seconds. The function selector is spring loaded to STBY.
Code Selectors Select the transponder code. Left and right selectors consist of a large knob and a small knob. Each knob controls one digit of the code.
Figure A-2. TCAS II – Traffic Display (Example)
Table A- 2. Displayed Aircraft Symbols (Examples) Arrow indicates that the target is climbing ↑ or descending ↓ at a rate of at least 500 fpm.
Relative altitude is displayed in the proximity of the aircraft symbol in hundreds of feet. A “+” preceding the relative altitude indicates the target is above you and a “-“ indicates it is below you.
Unfilled white diamond. Non-threatening traffic without altitude reporting. If altitude reporting, the altitude data will be displayed.
Appendix A A-6 Arrow indicates that the target is climbing ↑ or descending ↓ at a rate of at least 500 fpm.
+07
Solid White diamond. Proximity traffic 700 feet above. Nonthreatening, altitude reporting traffic within 1200 feet vertically and 6nm horizontally. Aircraft without altitude reporting will be assumed to be co-altitude and will be displayed as a solid diamond when within 6nm even though they may not be within 1200 feet vertically.
↓ -03 Solid yellow circle. “TA”, 300 feet below, descending with a rate of at least 500 fpm.
+00 Solid red square. “RA”, level at your altitude.
Ownship. Airplane symbol in white just below the center of CRT.
On a dedicated display or when in the TFC Mode on a combination TCAS II/RADAR Display.
(Compass Arc) This arc is a repeater of the Captain’s compass. (Not required for TCAS II Display) (Range Rings) 3nm – Small ring with ticks at clock positions 5 NM – Large ring made of dots.
Figure A-3. TCAS II Traffic Display (Example)
Appendix A A-7 Table A- 3. REL ALT/FL Switch REL ALT Paddle switch is spring loaded to the center position. Display shows relative altitude “REL ALT” in hundreds of feet above (+) or below (- ) your aircraft.
FL Allows display of traffic flight levels, referenced to 29.92, for 15 seconds. Your FL is displayed in lower left corner. Display shows three digits, except for negative flight levels that are shown as – xxx.
When the current barometric pressure is not available and the TCAS II aircraft is below FL 180, the system automatically inhibits display of FL.
RANGE Sets the maximum forward range on the traffic display. Ranges of 3, 5, 10, 20 NM are available and the traffic display shows the selected range in the upper right corner of the display.
BRT Knob Controls brightness of the display.
Appendix A A-8 Table A- 4. Above/Norm/Below Switch ABOVE Displays altitude-reporting traffic from 2700 feet below to 9900 feet above the TCAS II aircraft. In this mode, ABOVE shows on the traffic display. This selection has no effect on the functioning of the collision avoidance logic.
NORM Displays altitude reporting traffic from 2700 feet below to 2700 feet above the TCAS II aircraft.
BELOW Displays altitude-reporting traffic from 2700 feet above to 9900 feet below the TCAS II aircraft. In this mode, BELOW shows on the traffic display. This selection has no effect on the functioning of the collision avoidance logic.
OFF-SCALE TRAFFIC ADVISORY - If TCAS II tracks an intruder that is outside the selected range of the display but that has entered the Caution or Warning areas, one-half of the appropriate symbol will appear at the appropriate bearing at the edge of the display area. The symbol will appear in its proper color and its data tag will show, if there is room. For example, a TA intruder with a high closure rate, and which is directly ahead and 300 feet below your airplane will appear as an amber-filled half circle at the 12 o’clock position on the edge of the display area. The data tag “-03” will appear below the half symbol. If this intruder is above your altitude, the data tag is not visible. An off-scale RA intruder will appear as a red-filled half square, with data tag if room permits.
NO BEARING ADVISORIES - When TCAS II cannot track the bearing of an intruder, the traffic advisory will appear in the lower center of the display just below the own-airplane symbol. The advisory will present appropriate color-coded traffic information. This phenomenon usually is a result of either temporary antenna shielding (due to steep bank angles) or a failure in the TCAS II bearing antenna. The display can show up to two lines of information. “TA 5.2 -06↑” for example means an intruder is creating a Traffic Advisory 5.2 nautical miles away, 600 feet below, and climbing in excess of 500 FPM. This advisory is displayed in amber or yellow. “RA 0.6 00” means resolution advisory traffic is 0.6 nautical miles away at the same altitude. This advisory is displayed in red. Lack of bearing information does not degrade TCAS II’s ability to compute a traffic or resolution advisory.
Appendix A A-9
Figure A-4. TCAS II Instantaneous Vertical Speed Indicator (Example)
Table A- 5. Instantaneous Vertical Speed Indicator Indicates vertical speed in feet per minute. The IVSI is a normal instantaneous vertical speed indicator, and the presence of the lights or the flags will not interfere with the ability of the needle to indicate vertical speeds.
RED/GREEN EYEBROW LIGHTS. Eyebrow lights are invisible until they illuminate as part of a TCAS II “RESOLUTION ADVISORY”, or system “TEST”. These lights indicate a vertical speed regime which will provide safe traffic separation. The green lights form a wider band than red lights.
IVSI Status Window Flags T C A S BLACK. Normal operation.
T C A S AMBER FLAG. Indicates Unusable TCAS II information.
Red Arc Green Arc Key to Colors in Figures
Appendix A A-10 T C A S WHITE “RA OFF” FLAG. Always displayed when TCAS II/TRANSPONDER function selector is in STBY, XPDR, or TA. Will also be displayed with selector in RA/TA if RAs are not available.
R A O F F
Appendix A A-11 Figure A-5. TCAS II Examples – Preventive RAs
Appendix A A-12 Figure A-6. TCAS II Examples – Initial Corrective RAs
Appendix A A-13 Figure A-7. TCAS II Examples – Modifications to Initial Corrective RAs
Appendix A A-14 SECTION I – LIMITATIONS.
(1) Pilots are authorized to deviate from their current ATC clearance to comply with a TCAS II resolution advisory (RA).
(2) Maneuvers based solely on a traffic advisory (TA) or on information displayed on the traffic display are not authorized.
SECTION II - EMERGENCY PROCEDURES.
No change from basic airplane flight manual.
SECION III – PROCEDURES.
(1) TCAS II Flight Procedures:
Compliance with a TCAS II resolution advisory (RA) is necessary unless the pilot considers it unsafe to do so, or unless the pilot has information about the cause of the RA and can maintain safe separation for example visual acquisition of, and safe separation from, a nearby aircraft on a parallel approach.
WARNING: Once you get a non-crossing RA, you could compromise safe separation if you change the current vertical speed, except as necessary to comply with the RA. This is because TCAS II-to-TCAS II coordination may be in progress with the intruder airplane, and any change in vertical speed that does not comply with the RA may negate the effectiveness of the other airplane’s compliance with its RA.
WARNING: Noncompliance with a crossing RA by one airplane may result in reduced vertical separation; therefore, you must also ensure safe horizontal separation by visual means.
Because of the limited number of inputs to TCAS II for airplane performance inhibits, in some instances where inhibiting RAs may be appropriate it is not possible to do so. In these cases, TCAS II may command maneuvers that may significantly reduce stall margins or result in stall warning. Therefore, you must respect the stall warning stick shaker when following an RA.
Conditions where this may occur include:
(a) Bank angle in excess of 15 degrees.
(b) One engine inoperative.
(c) Abnormal configurations such as landing gear not retractable, etc.
(d) Leaving airplane in inappropriate configurations when climb RA occurs.
(e) Operation at airports outside of 0 to 5,300 feet MSL or temperatures outside of ISA ±50°F.
(f) Speeds below normal operating speeds.
(g) Buffet margin less than 0.3 g.
Appendix A A-15 The TCAS II RA algorithms assume that the pilot initiates an initial 0.25 g acceleration maneuver within approximately 5 seconds. The pilot must respond within approximately 2.5 seconds if the system issues an additional RA. (You should fly any increase rate and rate reversal RAs using a 0.35 g acceleration maneuver.) Because of these requirements and the rate limits of the autopilots, you must disengage the autopilot and autothrottles and hand-fly all RA responses.
Note: You should limit evasive maneuvering to the minimum required to comply with the RA. Excessive responses to RAs are not desirable or appropriate because of other potential traffic and ATC consequences. From level flight, proper response to an RA typically results in an overall altitude deviation of 300 to 500 feet in order to successfully resolve a traffic conflict.
After the crew has completed its response to an initial advisory and the TCAS II system projects that the airplane will have adequate altitude separation from the intruder, the system will post modified advisories if necessary. The initial RA will “weaken”, indicating that the crew may return towards the original flight path or clearance. When the initial advisory weakens, the green arc repositions to indicate level flight, the magnitude of the red arc decreases, and the system announces “LEVEL OFF, LEVEL OFF”. The modified RA indicates a return to level flight so that the flight crew can minimize altitude deviation in response to the initial RA. This RA will remain displayed until the TCAS II issues a “CLEAR OF CONFLICT” aural annunciation. Following the weakening advisory will greatly reduce the ultimate altitude deviation caused by the original corrective resolution advisory.
If the system issues a “CLIMB” RA while the aircraft is in the landing configuration, initiate normal go-around procedures.
Note: Initiating go-around procedure for a “CLIMB” RA does not mandate a missed approach. The purpose of initiating the go-around procedure in this case is to ensure proper airplane configuration for the TCAS II maneuver. In most cases, the aircraft will be clear of conflict with only minor deviation to the intended flight path, and sufficient time and altitude may exist to recover safely to the desired flight path.
The pilot should not initiate evasive maneuvers using information from the traffic display only or on a traffic advisory (TA) only without visually sighting the traffic. These displays and advisories are intended only for assistance in visually locating the traffic. They lack the flight path trends necessary for use in evasive maneuvering.
TCAS II can issue unnecessary resolution advisories when other aircraft are operating at an altitude adjacent to the one assigned to the climbing or descending TCAS aircraft. When climbing or descending in an environment where these unnecessary advisories are considered likely to occur (based on either airspace design, air traffic communications, visual acquisition or utilization of traffic displays), the flight crew should reduce vertical velocity until reaching the assigned altitude. As appropriate, the flight crew should reduce vertical velocity to a rate between 500 and 1,500 ft/min, when approaching an altitude between 1,000 and 2,000 ft. above or below the altitude assigned in the ATC instruction or clearance.
After deviating from an ATC clearance or instruction in response to a TCAS II RA, notify ATC of the deviation as soon as possible.