Flight Details
Aircraft Type: Boeing 737-76N Operator: Aerolíneas Argentinas Registration: LV-CBF Flight Number: AR1360 Route: Buenos Aires Jorge Newbery Aeroparque (AEP), Argentina to El Dorado International Airport (BOG), Bogotá, Colombia Date of Incident: 19 April 2025 Total Occupants: Not specified; typical seating for B737-700 approx. 128–144 passengers, 5–6 crew Weather Conditions: Enroute at FL350 in stable cruise; no weather-related factors reported
Introduction
On 19 April 2025, a Boeing 737-700 operated by Aerolíneas Argentinas diverted back to Buenos Aires shortly after entering cruise when the first officer’s flight instruments went blank. The aircraft had reached FL350 and was approximately 220 nautical miles north of its departure airport when the anomaly occurred. The flight crew elected to return to Buenos Aires Aeroparque and entered a holding pattern at FL100 to reduce landing weight before executing a safe landing on runway 13 approximately four hours after initial departure. There were no reported injuries, and a replacement aircraft completed the flight to Bogotá later that day.
Sequence of Events
Flight AR1360 departed Buenos Aires Jorge Newbery Aeroparque on a scheduled international service to Bogotá. After an uneventful climb, the aircraft levelled off at FL350 and continued on course. Approximately 220 nautical miles north of Buenos Aires, the first officer’s primary flight display (PFD) and navigation display (ND) went blank, indicating a loss of electrical power or data to their instrumentation suite.
Despite the captain’s displays functioning normally, and the aircraft maintaining full controllability, the crew elected to return to Buenos Aires as a precaution. While modern aircraft are certified to operate with one set of functional instruments, the failure of one pilot’s display systems during an international ETOPS segment presents elevated operational risk.
The flight crew initiated a turnback, descended to FL100, and entered a fuel hold to reduce landing weight below maximum structural limits. A safe landing was completed on Aeroparque’s runway 13. The aircraft taxied to the gate under its own power.
Crew & Communication
The crew’s decision to return was consistent with Boeing’s flight crew operations manual (FCOM) guidance, which emphasises redundancy and procedural caution in the event of partial cockpit display loss.
Key crew actions included:
Cross-verification of flight path and navigation using captain’s instrumentation Checklist execution for DU failure (Display Unit) or electrical fault Communications with ATC to declare intention and request holding Monitoring of secondary systems for associated failures (e.g. IRS, FMC sync, standby instruments)
The return was executed under standard ATC coordination without a formal emergency declaration. The flight remained in controlled airspace and maintained continuous communication throughout.
Aircraft Systems & Technical Analysis
The Boeing 737-700 flight deck uses six cathode-ray tube (CRT) or LCD display units (depending on avionics version): two PFDs, two NDs, and two centralised EICAS/MFD displays. Each pilot’s side receives data from independent sources but shares multiple buses for redundancy.
Loss of the first officer’s instruments could be attributed to:
Display unit failure (DU dark) Loss of electrical bus (e.g. right AC or DC bus) Fault in the symbol generator or data transfer module Wiring or connector fault at the rear avionics bay Air Data Inertial Reference Unit (ADIRU) channel fault
It is not yet known whether the failure was abrupt or progressive, or whether attempts to cycle breakers or reconfigure power were successful in restoring functionality.
The fact that the aircraft returned to service approximately 20 hours later suggests a line-replaceable unit (LRU) was swapped, and no extensive structural or wiring repair was needed.
Passenger Experience & Cabin Conditions
There are no reports of turbulence, smoke, or abnormal cabin conditions. Passengers were likely unaware of the specific nature of the fault, as the aircraft continued to fly smoothly and without apparent systems degradation.
Cabin crew would have been informed of the return and communicated with passengers accordingly. There were no emergency declarations, oxygen deployment, or diversions outside the planned airports.
A replacement Boeing 737-700 (registration LV-BZO) was dispatched and departed several hours later, completing the flight to Bogotá with a delay of approximately six hours and fifteen minutes.
Emergency Response & Aftermath
No emergency response activation was necessary, as the return was managed under standard operating conditions. Ground engineers met the aircraft upon arrival to begin diagnostics.
Post-landing maintenance involved:
Fault isolation of first officer’s display stack Circuit continuity checks Swap of failed display unit or reconfiguration of symbol generator Possible data logging review from the flight data acquisition unit (FDAU)
The aircraft returned to service the following day, indicating that the issue was contained and resolved without deeper airframe or power distribution implications.
Investigation Status
This event did not trigger a formal investigation but will be recorded under operational reliability monitoring. Aerolíneas Argentinas will have logged the defect under its reliability programme and reported to the Argentine civil aviation authority (ANAC) per standard protocol.
Any recurrence of display or electrical faults in LV-CBF would prompt escalation to Airbus/Boeing engineering support or further manufacturer intervention.
Root Cause & Contributing Factors
Preliminary technical hypotheses include:
Single display unit failure due to internal electronics degradation Symbol generator malfunction, affecting multiple screens on one side Power bus or circuit breaker fault in the right-side display supply ADIRU or display controller fault affecting data supply to the PFD/ND
Environmental or operational stress factors—such as high humidity, recent maintenance activity, or vibrations—could have contributed to intermittent electrical contacts.
Safety Recommendations & Industry Impact
While no urgent recommendations are anticipated, the incident highlights the continued need for:
Rigorous LRU tracking and proactive component replacement nearing time limits Emphasis on crew proficiency with monitored flying using single pilot instrumentation Updating maintenance protocols for older 737NG avionics, particularly in high-use fleets
As aircraft age, cockpit electronics—particularly CRT or early LCD units—are more susceptible to electrical failure, requiring vigilance in predictive maintenance planning.
Conclusion
The diversion of Aerolíneas Argentinas flight AR1360 due to a first officer instrumentation failure was handled professionally and without incident. The crew’s decision to return reflects prudent risk management when faced with cockpit redundancy degradation on an international segment.
With no injuries, damage, or extended disruption, the incident remains a textbook case of systems-level alertness, redundancy awareness, and procedural adherence.
Disclaimer
This article is based on publicly available information and reports at the time of writing. While every effort has been made to ensure accuracy, we cannot guarantee the completeness of the information provided.
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