# Service difficulty reports: JASC 3433 A list on [JASC 3433](https://openairdocs.org/jasc/3433.md). Reports filed under 3433 · Microwave Landing System, newest first. - [SDR AALA202505159407](https://openairdocs.org/sdr/AALA202505159407.md): Transceiver · faulted · May 13, 2025 · N933AN · Boeing 737823 > AIRCRAFT WAS GROUNDED: AT 10.000FT RED LANDING GEAR WARNING LIGHTS AND HORN CAME UP. **SUPPLEMENTAL REPORT FOR (AALA202505149407): REMOVE AND REPLACED RADIO ALTIMETER TRANSCEIVER (AALA202505149407), PER AMM 34-33-21. REMOVE AND REPLACED ALL 4 RADIO ANTENNAS (A - [SDR AALA202505156359](https://openairdocs.org/sdr/AALA202505156359.md): Antenna · faulty · May 13, 2025 · N933AN · Boeing 737823 > AIRCRAFT WAS GROUNDED: AT 10.000FT RED LANDING GEAR WARNING LIGHTS AND HORN CAME UP. **SUPPLEMENTAL REPORT FOR (AALA202505149407): REMOVE AND REPLACED RADIO ALTIMETER TRANSCEIVER (AALA202505149407), PER AMM 34-33-21. REMOVE AND REPLACED ALL 4 RADIO ANTENNAS (A - [SDR AALA202505154554](https://openairdocs.org/sdr/AALA202505154554.md): Antenna · faulty · May 13, 2025 · N933AN · Boeing 737823 > AIRCRAFT WAS GROUNDED: AT 10.000FT RED LANDING GEAR WARNING LIGHTS AND HORN CAME UP. **SUPPLEMENTAL REPORT FOR (AALA202505149407): REMOVE AND REPLACED RADIO ALTIMETER TRANSCEIVER (AALA202505149407), PER AMM 34-33-21. REMOVE AND REPLACED ALL 4 RADIO ANTENNAS (A - [SDR AALA202505150214](https://openairdocs.org/sdr/AALA202505150214.md): Antenna · faulty · May 13, 2025 · N933AN · Boeing 737823 > AIRCRAFT WAS GROUNDED: AT 10.000FT RED LANDING GEAR WARNING LIGHTS AND HORN CAME UP. **SUPPLEMENTAL REPORT FOR (AALA202505149407): REMOVE AND REPLACED RADIO ALTIMETER TRANSCEIVER (AALA202505149407), PER AMM 34-33-21. REMOVE AND REPLACED ALL 4 RADIO ANTENNAS (A - [SDR AALA202505154106](https://openairdocs.org/sdr/AALA202505154106.md): Antenna · faulty · May 13, 2025 · N933AN · Boeing 737823 > AIRCRAFT WAS GROUNDED: AT 10.000FT RED LANDING GEAR WARNING LIGHTS AND HORN CAME UP. REMOVE AND REPLACED RADIO ALTIMETER TRANSCEIVER (AALA202505149407), PER AMM 34-33-21. REMOVE AND REPLACED ALL 4 RADIO ANTENNAS (AALA202505156359, AALA202505154554, AALA202505 - [SDR SWAA2025050768358](https://openairdocs.org/sdr/SWAA2025050768358.md): Receiver · faulted · May 6, 2025 · N8943Q · Boeing 7378 > SPOILERS LIGHT ILLUMINATED ON APPROACH AFTER SELECTING FLAPS 30.<[01] R&R #1 & #2 LRRA R/T PER AMM 34-33-21

AIRCRAFT RECTIFIED TO CAT III STATUS PER 834-PDR-01-01 VERIFICATION# 47585 - [SDR SWAA2025050768375](https://openairdocs.org/sdr/SWAA2025050768375.md): Receiver · faulted · May 6, 2025 · N8943Q · Boeing 7378 > SPOILERS LIGHT ILLUMINATED ON APPROACH AFTER SELECTING FLAPS 30.<[01] R&R #1 & #2 LRRA R/T PER AMM 34-33-21

AIRCRAFT RECTIFIED TO CAT III STATUS PER 834-PDR-01-01 VERIFICATION# 47585 - [SDR AALA202504087941](https://openairdocs.org/sdr/AALA202504087941.md): Altimeter · false indication · Apr 7, 2025 · N300UB · Boeing 7378 > AIRCRAFT WAS GROUNDED: LANDING GEAR WARNING HORN AND GEAR UNSAFE LIGHTS ILLUMINATED MULTIPLE TIMES DURING DESCENT. REPLACED NUMBER 2 RADIO ALTIMETER. - [SDR AALA202504081451](https://openairdocs.org/sdr/AALA202504081451.md): Antenna · undertorqued · Apr 6, 2025 · N300UB · Boeing 7378 > AIRCRAFT WAS GROUNDED: GEAR WARNING HORN AND RED LIGHTS ON INTERMITTENTLY ON DESCENT FROM FL230 TO ABOUT 15000. PERFORMED BITE TEST ON BOTH LRRA TRANSCEIVERS, PER AMM 34-33-00 BITE TEST PASS. FOUND ALL SCREWS ON ALL 4 LRRA ANTENNAS LESS THAN 30 INCH LBS. HALF - [SDR AALA202410044170](https://openairdocs.org/sdr/AALA202410044170.md): Transmitter · inoperative · Oct 2, 2024 · N806NN · Boeing 737823 > AIRCRAFT WAS GROUNDED: SELECTED APPROACH MODE FOR THE ILS 25L AT LAX. LOC STARTED TO CAPTURE WHEN WE LOST BOTH FLIGHT DIRECTORS AND AUTO THROTTLES. AS WELL AT AUTO PILOT. COMMAND A SELECTED. TRIED THE APPROACH AGAIN WITH THE SAME RESULT. DIVERTED TO ONT FOR A - [SDR AALA202402226510](https://openairdocs.org/sdr/AALA202402226510.md): Antenna · faulty · Feb 20, 2024 · N897NN · Boeing 737823 > AIRCRAFT WAS NOT GROUNDED: AN EMERGENCY WAS DECLARED AND LANDED SAFELY AT LAX DUE TO: DURING CAPTURE OF ILS, LEFT SIDE FLIGHT DIRECTOR FAILED AND LOST GUIDANCE CUES, ON SUBSEQUENT APPROACH IT FAILED AGAIN. REMOVED AND REPLACED (LRRA) LOW RANGE RADIO ALTIMETER - [SDR ASAA2021080435621](https://openairdocs.org/sdr/ASAA2021080435621.md): Autoland Sys · faulted · Aug 4, 2021 · N587AS · Boeing 737890 > ATTEMPTED AUTOLAND & HGS AIII, DEVELOPED A HIGH SINK RATE AND DID NOT FLARE. THEN APP/WARN IN THE HUD. DISCONNECTED A/P A/T AND LANDED MANUALLY. GROUNDED - YES. CHECKED FOUND HGS APCH WARN FOR LEG 6 AIRSPEED EXCEEDANCE. HGS SYSTEM TEST PASSED REF HGS 4000 SSM - [SDR UIEA2021042801014](https://openairdocs.org/sdr/UIEA2021042801014.md): Transceiver · intermittent · Apr 28, 2021 · N649GT · Boeing 767300 > FO RA INTERMITTENT (NO LAND 3) REMOVED AND REPLACED RT RA XCEIVER, OPS CK OK. THIS CLEARS MDDR 146046.

) - [SDR AALA201909059004](https://openairdocs.org/sdr/AALA201909059004.md): Transceiver · unreliable · Sep 2, 2019 · N816NN · Boeing 737823 > AIRCRAFT WAS GROUNDED: PILOT REPORTS DESCENDING THROUGH 8000 (LVL CHG, POWER IDLE). ALL RED LIGHTS ON GEAR INDICATORS AND WARNING HORN ON. FLAPS 5 AIRSPEED 210 KIAS. MAINTENANCE REPLACED #1 & #2 R/A R/TS IAW AMM 34-33-21. REPLACED ALL R/A ANTENNA IAW AMM 34-33 - [SDR AALA201909059016](https://openairdocs.org/sdr/AALA201909059016.md): Transceiver · unreliable · Sep 2, 2019 · N816NN · Boeing 737823 > AIRCRAFT WAS GROUNDED: PILOT REPORTS DESCENDING THROUGH 8000 (LVL CHG, POWER IDLE). ALL RED LIGHTS ON GEAR INDICATORS AND WARNING HORN ON. FLAPS 5 AIRSPEED 210 KIAS. MAINTENANCE REPLACED #1 & #2 R/A R/TS IAW AMM 34-33-21. REPLACED ALL R/A ANTENNA IAW AMM 34-33 - [SDR AALA201909059017](https://openairdocs.org/sdr/AALA201909059017.md): Antenna · unreliable · Sep 2, 2019 · N816NN · Boeing 737823 > AIRCRAFT WAS GROUNDED: PILOT REPORTS DESCENDING THROUGH 8000 (LVL CHG, POWER IDLE). ALL RED LIGHTS ON GEAR INDICATORS AND WARNING HORN ON. FLAPS 5 AIRSPEED 210 KIAS. MAINTENANCE REPLACED #1 & #2 R/A R/TS IAW AMM 34-33-21. REPLACED ALL R/A ANTENNAS IAW AMM 34-3 - [SDR AALA201908319010](https://openairdocs.org/sdr/AALA201908319010.md): Antenna · faulty · Aug 29, 2019 · N877NN · Boeing 737823 > AIRCRAFT WAS GROUNDED: PILOT REPORTS ON FINAL APPROACH WITH COUPLED ILS IN COMMAND B, CAPTAINS FO BARS DISAPPEARED AND BOTH FD MASTER LIGHTS CAME ON. MAINTENANCE TROUBLESHOT IAW FIM TASK 22-11-00-810-801; FOUND MULTIPLE INSTANCES OF FAULT CODE 22-11051, NO RA - [SDR AALA2019060429002](https://openairdocs.org/sdr/AALA2019060429002.md): Radio Altimeter · malfunctioned · Jun 1, 2019 · N194AA · Boeing 757223 > AIRCRAFT NOT GROUNDED: PILOT REPORTS ON APPROACH 1800 RADIO ALTITUDE FLAPS 20 THROTTLES IDLE, GOT CONFIG WARNING, MASTER CAUTION GEAR NOT DOWN MSG EXTENDED GEAR, FLAPS 25 ALL WARNINGS STOPPED WITH THROTTLES NOT AT IDLE 1800 RA FLAPS 20. MAINTENANCE ACCOMPL - [SDR FDEA201902150416](https://openairdocs.org/sdr/FDEA201902150416.md): Autoland Sys · malfunctioned · Feb 15, 2019 · N968FD · Boeing 75728A > PDIS 968 22-20 4737 14FEB19 TLV FACT U LOGPAGES:3011346 3011350 REPEAT EVENT: IN VNAV PATH @ 350, DECENDING TO 210, ACT WENT FROM VNAV PATH TO VNAV SPEED AND PITCHED DOWN AGRESSIVLEY TO 10 DEG NOSE LOW AND OVER 7000FPM DESCENT. DURING DESCEN - [SDR ASAA2018042624418](https://openairdocs.org/sdr/ASAA2018042624418.md): Autoland Sys · malfunctioned · Apr 26, 2018 · N486AS · Boeing 737990ER > AUTOLAND NOT SUCCESSFUL, AIRCRAFT LANDED 50FT LEFT OF CENTERLINE. ACFT GROUNDED. ACCOMPLISHED FIM 22-11 TASK 825. PERFORMED LAND VERIFY TEST IAW AMM 22-11-00. ALL TESTS PASSED. NO FAULTS FOUND. ACCOMPLISHED AUTOPILOT CURRENT STATUS IAW AMM 22-11-00-740-801 - [SDR ASAA2018041724281](https://openairdocs.org/sdr/ASAA2018041724281.md): Autoland Sys · malfunctioned · Apr 17, 2018 · N577AS · Boeing 737890 > WHILE ACCOMPLISHING AUTOLAND, LAND VERIFY TEST, FOUND A FAILURE OF THE ELEVATOR PRESSURE SWITCH 1. ACFT GROUNDED. PERFORMED LLM TESTS OF AUTOLAND, 30 DAY IN USE IAW AMM 22-00-01-730-809 AND LLM TESTS FOR HGS 30 DAY IN USE IAW AMM 22-00-010730-810. NO FAULT - [SDR AALA201712089032](https://openairdocs.org/sdr/AALA201712089032.md): Antenna · faulty · Dec 4, 2017 · N901NN · Boeing 737823 > AIRCRAFT WAS GROUNDED: AFTER TAKEOFF AT 1000 FEET UNABLE TO ENGAGE NAVIGATION AUTO THROTTLE STAYED IN TOGA AT 5000 FT WHEN THROTTLES RETARD, LANDING GEAR WARNING HORN ON STEADY. HORN STAYED ON UNTIL GEAR WAS EXTENDED. LANDING WAS BELOW MAX LANDING. WEIGHT CONT - [SDR AALA20171204014](https://openairdocs.org/sdr/AALA20171204014.md): Antenna · faulty · Dec 4, 2017 · N901NN · Boeing 737823 > AIRCRAFT WAS GROUNDED: AFTER TAKEOFF AT 1000 FEET UNABLE TO ENGAGE NAVIGATION AUTO THROTTLE STAYED IN TOGA AT 5000 FT WHEN THROTTLES RETARD, LANDING GEAR WARNING HORN ON STEADY. HORN STAYED ON UNTIL GEAR WAS EXTENDED. LANDING WAS BELOW MAX LANDING. WEIGHT CONT - [SDR UALA2010100403661](https://openairdocs.org/sdr/UALA2010100403661.md): Transceiver · faulty · Oct 3, 2010 · N206UA · Boeing 777222 > A-T DISCONNECTED. NO LAND, 3 IND EICAS MSG AND STATUS MSGS. PERFORMED LT & RT F AUTO THROTTLE SERVO LOOP GROUND TEST, CONDITION NORMAL. PRESENT LEG FAULTS SHOWED RADIO ALT MSG 22-11920, 22-11940. CONCURED WITH S FOLM THAT ISSUE IS WITH LT & RT RADIO ALT AND N - [SDR P5CA0300961](https://openairdocs.org/sdr/P5CA0300961.md): Autoland Sys · malfunctioned · Oct 7, 2003 · N924FT · Boeing 747236B > LOUD SIDE TONE IN F/O INTERPHONE. RERACKED NR 2 LRRA - TRANSCEIVER IAW MM 34-42-00, OPS CHECK OK. NOISE DISAPPEARED. - [SDR CA961118014](https://openairdocs.org/sdr/CA961118014.md): Couplers · failed · Nov 11, 1996 · Cndair CL6002B19 > (CAN) BOTH CAPTAINS AND FIRST OFFICERS INSTRUMENT LANDING SYSTEM INOPERATIVE. ANTENNA COUPLERS REPLACED. ## The whole list in SQL Runs in DuckDB 1.2 or later on the release's Parquet files over HTTPS: ```sql SELECT sdr_id, difficulty_date, n_number, aircraft_make, aircraft_model, part_name, part_condition, jasc_code, discrepancy FROM 'https://openairdocs.org/data/latest/faa_service_difficulty_report.parquet' WHERE jasc_code = '3433' ORDER BY difficulty_date DESC ``` This list as a web page: https://openairdocs.org/jasc/3433/reports --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.