# JASC 3445: Air Collision Avoidance System

- Type: JASC system/component code (FAA)
- ATA chapter: 34 Navigation
- Title in the code table: AIR COLLISION AVOIDANCE SYSTEM (TCAS)
- Service difficulty reports: 214
- FAA code table: https://www.faa.gov/sites/faa.gov/files/JASC_Code.pdf#page=40
- Page: https://openairdocs.org/jasc/3445

## What it covers

The system which provides information to determine aircraft position and is primarily independent of ground installations (i.e., traffic alert and collision avoidance system - TCAS). Use this code only if the specific system creating the problem cannot be established. Typical parts are collision avoidance monitoring units, etc.

## Service difficulty reports (214, newest 50)

- [SDR AALA202609082369](https://openairdocs.org/sdr/AALA202609082369), Sep 6, 2026: Boeing 7378. TCAS SYSTEM. INOPERATIVE. AIRCRAFT WAS GROUNDED: RETURNED TO MIA ACCOUNT MAINTENANCE TCAS FAIL. EMERGENCY WAS NOT DECLARED AND AIRCRAFT WAS NOT OV (N341TR)
- [SDR CALA2026090719298](https://openairdocs.org/sdr/CALA2026090719298), Sep 4, 2026: Boeing 777224. COMPUTER. FAULTED. STATUS MESSAGE, TCAS & NO AUTOLAND. R & R THE TCAS COMPUTER DUE TO PREVIOUS HISTORY IAW AMM 34-45-01-400-801. OPS CHKD G (N77014)
- [SDR CALA2026073118134](https://openairdocs.org/sdr/CALA2026073118134), Jul 29, 2026: Boeing 737824. COMPUTER. FAULTY. TCAS FAIL FLAG ON NAVIGATION DISPLAY SHOWS WITH ATC TRANSPONDER SELECTOR AT TA AND SHOWS WITH SELECTOR AT TA/RA FAULT NO (N34222)
- [SDR CALA2026071417789](https://openairdocs.org/sdr/CALA2026071417789), Jul 12, 2026: Boeing 757224. COMPUTER. FAULTY. TCAS RA CLIMBING THRU 5000..CLIMB FOR 2000 FOLLOWED BY DESCEND WITH NO VISIBLE TRAFFIC, WORK WITH FIM 34-45 TASK 801. MT (N19141)
- [SDR CALA2026042815794](https://openairdocs.org/sdr/CALA2026042815794), Apr 28, 2026: Boeing 737724. ADIRU. FAILED. FLIGHT CREW REPORTED TCAS FAILED INFLIGHT FLAGGED FOR SDR REF FIM 34-45 TASK 801 BITE TEST OF TCAS FOUND HDNG FAULT. REM (N12754)
- [SDR IPXA2026020652253](https://openairdocs.org/sdr/IPXA2026020652253), Jan 30, 2026: Boeing 74744AF. ANTENNA. FAULTED. AIR TURN BACK, TCAS SYSTEM ADVISORY MESSAGE CHECK CMC PRESENT LEG FAULT.FND TCAS LOWER ANTENNA FAIL. REPLACED LOWER TACA (N570UP)
- [SDR CALA2026012113127](https://openairdocs.org/sdr/CALA2026012113127), Jan 18, 2026: Boeing 7379. COMPUTER. FAULTY. TCAS FAIL FLAG SHOWS ON ND CAPTAIN'S. PERFORMED WIRING CHECK FOR TCAS TOP & BOTTOM ANTENNA & CHECKED TCAS COMPUTER UNIT  (N37542)
- [SDR P5CA2026011500001](https://openairdocs.org/sdr/P5CA2026011500001), Jan 15, 2026: Boeing 777FZB. CONTROL PANEL. FAULTED. EICAS TRANSPONDER R STATUS MSG, EICAS TRANSPONDER L STATUS MSG, EICAS TCAS STATUS MSG. R & R TCAS CONTROL PANEL IAW B777 (N714SA)
- [SDR AALA202507246550](https://openairdocs.org/sdr/AALA202507246550), Jul 22, 2025: Boeing 7378. COMPUTER. FAILED. AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED DUE TO: TACAS FAILED ON TAKEOFF AND CLIMB WOULD NOT RESET. AIRCRAFT AIR (N339SU)
- [SDR CALA2025072306860](https://openairdocs.org/sdr/CALA2025072306860), Jul 21, 2025: Boeing 757224. COMPUTER. UNKNOWN. TCAS INOP, TCAS INOPERATIVE. TCAS FAIL BOTH TRANSPONDER COMPUTER, T/S IAW FIM 34-45 FAULT TREE 802. PERFORMED TCAS BITE  (N17128)
- [SDR CALA2025043004353](https://openairdocs.org/sdr/CALA2025043004353), Apr 28, 2025: Boeing 777222. COMPUTER. FAULTED. TCAS FAIL BOTH SIDES REMOVED AND INSTALLED TCAS COMPUTER. REF AMM 34-45-01. TCAS SYS TEST PASSED. REF AMM 34-45-01. (N786UA)
- [SDR ABXA20250410074](https://openairdocs.org/sdr/ABXA20250410074), Apr 11, 2025: Boeing 76737D. TCAS SYSTEM. FAULTED. DURING PUSHBACK GOT TCAS EICAS MSG. A/C RETURNED TO GATE (BTB) AND MTX GROUNDED A/C, MTX DEFERRED TCAS FOR DEPARTURE IAW (N1327A)
- [SDR UIEA2025030190216](https://openairdocs.org/sdr/UIEA2025030190216), Mar 15, 2025: Boeing 76731K. ANTENNA. CORRODED. CORROSION ON BOTTOM TCAS ANTENNA.(<P>TCAS ANTENNA BOTTOM WAS REPLACED, ON P/N 071-50001-8102 S/N 582-34534, OFF P/N 071- (N1373A)
- [SDR DALA2025021901270](https://openairdocs.org/sdr/DALA2025021901270), Feb 14, 2025: Boeing 757232. COAX. DAMAGED. SHIP 6715 -DIV- TO SLC DUE TO ERRONEOUS TCAS ADVISORIES. CORRECTIVE ACTION: DEFERRED TO MEL. (SUBSEQUENTLY WIRING AND CO (N6715C)
- [SDR UIEA2024120101139](https://openairdocs.org/sdr/UIEA2024120101139), Jan 15, 2025: Boeing 76738E. ANTENNA. CORRODED. CORROSION ON BASE ANTENNA TCAS UPPER FUSELAGE(<P>TCAS ANTENNA WAS REPLACED WITH SATISFACTORY TEST IAW AMM 34-45-02-344-1 (N641GT)
- [SDR UIEA2025010900009](https://openairdocs.org/sdr/UIEA2025010900009), Jan 14, 2025: Boeing 76731B. ANTENNA. CORRODED. UPPER TCAS ANTENNA WITH CORROSION ON THE BASE.(<P>6734A112/002 UPPER TCAS ANTENNA WITH CORROSION ON THE BASE. UPPER TCAS (N664GT)
- [SDR AALA202409302327](https://openairdocs.org/sdr/AALA202409302327), Sep 27, 2024: Boeing 737823. COMPUTER. INOPERATIVE. AIRCRAFT WAS GROUNDED: TCAS INOP BOTH TRANSPONDERS. RETURNED TO FIELD EMERGENCY DECLARED LANDED WITHOUT INCIDENT. REMOVE (N954AN)
- [SDR 2024FA0000830](https://openairdocs.org/sdr/2024FA0000830), Aug 26, 2024: LIDAR. BROKEN. THE OBSTACLE AVOIDANCE SYSTEM DID NOT ACTIVATE WHEN IT CAME TO A TREE. (UAS) 
- [SDR AALA202405076496](https://openairdocs.org/sdr/AALA202405076496), May 5, 2024: Boeing 777323ER. COMPUTER. FAULTED. AIRCRAFT WAS GROUNDED: TCAS FAIL ILLUMINATED ON DEPARTURE AFTER A POSSIBLE STATIC DISCHARGE. FAIL LIGHT EXTINGUISHED ON  (N736AT)
- [SDR ABXA2024042886](https://openairdocs.org/sdr/ABXA2024042886), Apr 28, 2024: Boeing 767383. WARNING SYSTEM. UNKNOWN. ON FIRST APPROACH TO MIA GPS WWARNING TERRAIN. A/C HAD GEAR/FLAPS DOWN AND WAS ON GLIDE SLOPE FOR RWY 9. SECOND APPROACH (N226CY)
- [SDR DALA2024020901781](https://openairdocs.org/sdr/DALA2024020901781), Feb 8, 2024: Boeing 757232. COMPUTER. INOPERATIVE. SHIP 6704 -ATB- DUE TO TCAS INOP. UNABLE TO CONTINUE DUE TO THEATER RESTRICTIONS. CORRECTIVE ACTION: REPLACED TCAS COMPU (N6704Z)
- [SDR AALA202310025988](https://openairdocs.org/sdr/AALA202310025988), Sep 30, 2023: Airbus A319112. CONTROL PANEL. WARNING MESSAGE. AIRCRAFT WAS GROUNDED: TCAS AURAL ALERT "TCAS SYSTEM TEST OK" CONTINUES IN FLIGHT EVERY 15-30 SECONDS, BURNING ELECTRICA (N753US)
- [SDR DALA2023090807358](https://openairdocs.org/sdr/DALA2023090807358), Sep 8, 2023: Airbus A320212. UNKNOWN. UNKNOWN. SHIP 3255 NAV TCAS ECAM MSG ON TAXI IN. CORRECTIVE ACTION: PERFORMED NAV TCAS BITE TEST PER A320 AMM 34-43 TEST PASSED.  (N355NW)
- [SDR UIEA2023080800774](https://openairdocs.org/sdr/UIEA2023080800774), Aug 8, 2023: Boeing 747443. UNKNOWN. UNKNOWN. TCAS INOP(<P>PERFORMED TCAS OPS CHECK. OPC CHECK GOOD. PERFORMED TCAS GROUND TEST, TEST PASSED. PERFORMED LRU ATC LT &AM (N482MC)
- [SDR UIEA2023061400639](https://openairdocs.org/sdr/UIEA2023061400639), Jun 13, 2023: Boeing 747443. COMPUTER. UNKNOWN. AT 2000 FT AFTER TAKEOFF, EICAS MSG "TCAS OFF" WHILE TRANSPONDER PROPERLY SET. ATC REPORTED BEING UNABLE TO SEE US ON TH (N482MC)
- [SDR CALA2023051101453](https://openairdocs.org/sdr/CALA2023051101453), May 10, 2023: Boeing 777224. COMPUTER. FAILED. TCAS FAIL AFTER TAKEOFF INTERROGATED MAT AND PERFORMED TCAS SYSTEM TEST, FOUND MX MESAGE FAULTS PRESENT AT THIS TIME, OP (N78005)
- [SDR 2023F00083](https://openairdocs.org/sdr/2023F00083), Mar 16, 2023: Boeing 7378Q8. UNKNOWN. UNKNOWN. TCAS FAIL ON GROUND. FLIGHT CANCELLED. CORRECTIVE ACTION: FAULT ISOLATION PERFORMED TH THE TCAS TOP ANTENNA IAW FIM 34-4
- [SDR 7C7A2023011730002](https://openairdocs.org/sdr/7C7A2023011730002), Jan 13, 2023: Dhav DHC8106. RELAY. FAILED. TCAS INOP DURING CRUISE, DEFERRED TCAS SYSTEM. REPLACED RELAY 3452-K6 FOR FIX (N893EA)
- [SDR UIEA2023011200016](https://openairdocs.org/sdr/UIEA2023011200016), Jan 11, 2023: Boeing 7478F. TCAS SYSTEM. FAILED. DUAL TCAS SYSTEM FAILURE AT CRUISE. CAN'T ENTER CHINESE AIRSPACE WITHOUT TCAS. AIR RETURN TO ICN. R & R RT CMC & OPS & S (N860GT)
- [SDR 7C7A2022121300038](https://openairdocs.org/sdr/7C7A2022121300038), Dec 7, 2022: Dhav DHC8106. CONTROLLER. FAILED. TCAS FAIL. TCAS CONTROLLER WAS CHANGED (N893EA)
- [SDR 7C7A2022120700034](https://openairdocs.org/sdr/7C7A2022120700034), Dec 7, 2022: Dhav DHC8106. PROCESSING UNIT. FAILED. TCAS FAILED. (N893EA)
- [SDR 9JLA2022091530493](https://openairdocs.org/sdr/9JLA2022091530493), Sep 6, 2022: Cessna 560XL. TCAS SYSTEM. FAILED. THE FLIGHT CREW REPORTED THAT DURING PREFLIGHT CHECKS FINDING THE TCAS SYSTEM FAILED. THE SYSTEM WOULD NOT EVEN TEST. TH (N561MT)
- [SDR CALA2022083102231](https://openairdocs.org/sdr/CALA2022083102231), Aug 30, 2022: Boeing 757. SKIN. NONE. SUPPORT TASK - LOWER TCAS ANTENNA 4 EACH DOME NUTS FAIL BOND CHE CK. TRANSCRIBED FROM HAECO GSO NR 9284527. ALL WORK COM (N14120)
- [SDR UIEA2022071500765](https://openairdocs.org/sdr/UIEA2022071500765), Jul 14, 2022: Boeing 74747UF. ANTENNA. FAULT MESSAGE. TCAS STATUS MESSAGE (REMOVED AND REPLACED TCAS COMPUTER AND TCAS LOWER ANTENNA IAW AMM 34-45-01 AND 34-45-02 BOTH OPS CH (N409MC)
- [SDR 9JLA2022031524161](https://openairdocs.org/sdr/9JLA2022031524161), Mar 6, 2022: Lear 45LEAR. TCAS SYSTEM. FAILED. THE FLIGHT CREW REPORTED THAT THE TCAS SYSTEM FAILED PREFLIGHT CHECKS. OPERATIONS WERE CONTINUED PER MEL 34-45-02 CAT C. (N546DH)
- [SDR VNAA202201289992](https://openairdocs.org/sdr/VNAA202201289992), Jan 28, 2022: Cndair CL6002C10. DOUBLER. CORRODED. LOWER TCAS ANTENNA INTERNAL DOUBLER IS CORRODED. (N537EA)
- [SDR 9JLA2021120612616](https://openairdocs.org/sdr/9JLA2021120612616), Dec 1, 2021: Raythn HAWKER900XP. TCAS SYSTEM. DEFECTIVE. THE FLIGHT CREW REPORTED ON FLIGHT LEG #2 THE TCAS FAIL INTERMITTENT ON PRIMARY FLIGHT DISPLAY. THE MAINTENANCE TEAM TRO (N887PC)
- [SDR UIEA2021071601576](https://openairdocs.org/sdr/UIEA2021071601576), Jul 15, 2021: Boeing 767306. CONTROL PANEL. FAILED. TCAS/ ATC CONTROL PANEL FAILED, RELEASED SMOKE FROM DISPLAY. REF L/P 1390638/ M8 SMOKE OR FUMES IN THE CABIN, INSP. REQU (N1409A)
- [SDR 9JLA2021080425522](https://openairdocs.org/sdr/9JLA2021080425522), Jul 8, 2021: Lear 45LEAR. COMMS UNIT. FAILED. THE FLIGHT CREW REPORTED AN "ADS-B FAIL" MESSAGE ON BOTH RTU UNITS AND "TCAS FAIL" MESSAGES ON MFD. WHEN USING BOTH RTS' (N445N)
- [SDR 9JLA2022042624561](https://openairdocs.org/sdr/9JLA2022042624561), Apr 30, 2021: Cessna 560CESSNA. TCAS SYSTEM. FAILED. THE FLIGHT CREW REPORTED THAT UPON POWER UP THE TCAS FAILED INITIALIZATION. THE BASE MAINTENANCE TEAM DETERMINED THE TCA (N64LV)
- [SDR SWIA2021072259681](https://openairdocs.org/sdr/SWIA2021072259681), Apr 20, 2021: Cndair CL6002C10. ANTENNA. CORRODED. * TCAS ANTENNA HAS CORROSION INTERNALLY AROUND CANNON PLUG CUTOUT AT APROX. FS295.00 STR.27 (C-CHECK RO 7/20/2021) REMOV (N790SK)
- [SDR CALA2021033000399](https://openairdocs.org/sdr/CALA2021033000399), Mar 30, 2021: Airbus A320232. TRANSCEIVER. FAILED. BOTH XPDR SYS FAILED AIR RETURN TO DENDUE TO INTL FLT TCAS FAULT DISPLAYED AT ENGINE START. REF TSM TASKS 34-43-00-810-8 (N465UA)
- [SDR A6WA202103227722](https://openairdocs.org/sdr/A6WA202103227722), Mar 21, 2021: Cndair CL6002B19. ANTENNA. DETACHED. 3819 - THOUGHT AT FLIGHT LEVEL 330 MAIN CABIN DOOR SEAL FAILED, INITIALLY HELD PRESSURE THEN CABIN STARTED TO CLIMB, DES (N431AW)
- [SDR HNAA2021030200066](https://openairdocs.org/sdr/HNAA2021030200066), Mar 1, 2021: Emb EMB145LR. RELAY. FAILED. DURING T/O ROLL AT ABOUT 30KTS, GPWS, TCAS, TERRAIN INOP EICAS MESSAGES WITH T/O CONFIG WARN WITH NO RELATED ORAL WARNIN (N652RS)
- [SDR FDEA202102260478](https://openairdocs.org/sdr/FDEA202102260478), Feb 26, 2021: Airbus A300B4622R. IRU. MALFUNCTIONED. PDIS 745 34-45 3202 26FEB21 MEM OPEN U LOGPAGES:366120 AT APPROXIMATELY 40 KNOTS ON TAKEOFF ROLL @ KMEM, F/O LOST ADI PR (N745FD)
- [SDR ASMF20200122001](https://openairdocs.org/sdr/ASMF20200122001), Nov 19, 2019: Boeing 7879. ANTENNA. FAILED. AIRCRAFT RETURNED TO PLATFORM DUE TO DURING TAXING BEFORE START THE TAKEOFF, THE TCAS LT AND TCAS RT MESSAGES WERE SHOWN (N128AM)
- [SDR AALA201910049006](https://openairdocs.org/sdr/AALA201910049006), Oct 3, 2019: Boeing 737823. TCAS SYSTEM. MALFUNCTIONED. AIRCRAFT WAS GROUNDED: PILOT REPORTS DURING CLIMB OUT TCAS FAIL ON ND. STARTED WORKING JUST PRIOR TO DESCENT. OPS NORMAL (N342PM)
- [SDR CALA2019092301626](https://openairdocs.org/sdr/CALA2019092301626), Sep 23, 2019: Boeing 737824. COMPUTER. INOPERATIVE. TCAS FAIL FLAG ON NAVIGATION DISPLAY SHOWS WITH ATC TRANSPONDER SELECTOR AT TA AND SHOWS WITH SELECTOR AT TA/RA FLAG DIS (N77535)
- [SDR DALA2019090905207](https://openairdocs.org/sdr/DALA2019090905207), Sep 6, 2019: Airbus A319114. COMPUTER. MALFUNCTIONED. SHIP 3162 - DIV - TO MIA DUE TO TCAS FAULT AT CRUISE. ECAM WARNING: NAV TCAS FAULT / CREW DECISION TO DIVERT. CORRECTIVE (N362NB)
- [SDR IPXA2019072544878](https://openairdocs.org/sdr/IPXA2019072544878), Jul 23, 2019: Boeing 74744AF. COMPUTER. MALFUNCTIONED. INSPECTION TYPE:N/A ATB- XPNDR 1 IN TA/RA SHOWED TCAS OFF, SWITCHED TO XPNDR 2 IN TA/RA SHOWED TCAS OFF. ATC COULD NOT S (N577UP)

All 214: https://openairdocs.org/jasc/3445/reports.md

## Other codes in chapter 34

- [JASC 3400](https://openairdocs.org/jasc/3400): Navigation System (692 reports)
- [JASC 3410](https://openairdocs.org/jasc/3410): Flight Environment Data (218 reports)
- [JASC 3411](https://openairdocs.org/jasc/3411): Pitot/Static System (1,586 reports)
- [JASC 3412](https://openairdocs.org/jasc/3412): Outside Air Temperature Indicator/Sensor (254 reports)
- [JASC 3413](https://openairdocs.org/jasc/3413): Rate of Climb Indicator (157 reports)
- [JASC 3414](https://openairdocs.org/jasc/3414): Airspeed/Mach Indicator (860 reports)
- [JASC 3415](https://openairdocs.org/jasc/3415): High Speed Warning (39 reports)
- [JASC 3416](https://openairdocs.org/jasc/3416): Altimeter, Barometric/Encoder (1,256 reports)
- [JASC 3417](https://openairdocs.org/jasc/3417): Air Data Computer (1,210 reports)
- [JASC 3418](https://openairdocs.org/jasc/3418): Stall Warning System (1,641 reports)
- [JASC 3420](https://openairdocs.org/jasc/3420): Attitude and Direction Data System (772 reports)
- [JASC 3421](https://openairdocs.org/jasc/3421): Attitude Gyro and Indicating System (1,142 reports)
- [JASC 3422](https://openairdocs.org/jasc/3422): Directional Gyro and Indicating System (649 reports)
- [JASC 3423](https://openairdocs.org/jasc/3423): Magnetic Compass (101 reports)
- [JASC 3424](https://openairdocs.org/jasc/3424): Turn and Bank/Rate of Turn Indicator (153 reports)
- [JASC 3425](https://openairdocs.org/jasc/3425): Integrated Flight System (1,148 reports)
- [JASC 3430](https://openairdocs.org/jasc/3430): Landing and Taxi Aids (56 reports)
- [JASC 3431](https://openairdocs.org/jasc/3431): Localizer/VOR System (129 reports)
- [JASC 3432](https://openairdocs.org/jasc/3432): Glide Slope System (66 reports)
- [JASC 3433](https://openairdocs.org/jasc/3433): Microwave Landing System (26 reports)
- [JASC 3434](https://openairdocs.org/jasc/3434): Marker Beacon System (27 reports)
- [JASC 3435](https://openairdocs.org/jasc/3435): Heads Up Display System (10 reports)
- [JASC 3436](https://openairdocs.org/jasc/3436): Wind Shear Detection System (70 reports)
- [JASC 3440](https://openairdocs.org/jasc/3440): Independent Position Determining System (261 reports)
- [JASC 3441](https://openairdocs.org/jasc/3441): Inertial Guidance System (289 reports)
- [JASC 3442](https://openairdocs.org/jasc/3442): Weather Radar System (3,442 reports)
- [JASC 3443](https://openairdocs.org/jasc/3443): Doppler System (110 reports)
- [JASC 3444](https://openairdocs.org/jasc/3444): Ground Proximity System (552 reports)
- [JASC 3446](https://openairdocs.org/jasc/3446): Non Radar Weather System (23 reports)
- [JASC 3450](https://openairdocs.org/jasc/3450): Dependent Position Determining System (106 reports)
- [JASC 3451](https://openairdocs.org/jasc/3451): DME/TACAN System (197 reports)
- [JASC 3452](https://openairdocs.org/jasc/3452): ATC Transponder System (624 reports)
- [JASC 3453](https://openairdocs.org/jasc/3453): Long-Range Navigation (LORAN) System (175 reports)
- [JASC 3454](https://openairdocs.org/jasc/3454): Visual Omnirange (VOR) System (317 reports)
- [JASC 3455](https://openairdocs.org/jasc/3455): Automatic Direction Finder (ADF) System (164 reports)
- [JASC 3456](https://openairdocs.org/jasc/3456): Omega Navigation System (9 reports)
- [JASC 3457](https://openairdocs.org/jasc/3457): Global Positioning System (635 reports)
- [JASC 3460](https://openairdocs.org/jasc/3460): Flight Management Computing Hardware System (4,690 reports)
- [JASC 3461](https://openairdocs.org/jasc/3461): Flight Management Computing Software System (68 reports)
- [JASC 3497](https://openairdocs.org/jasc/3497): Navigation System Wiring (269 reports)

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