Date: 201704
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Light: Daylight
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Parked
Aircraft component: ACARS
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: Pre-flight
Result: General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: This is a general safety report to cover the multitude of ACARS reliability issues I have experienced; especially this last week or so. Most recently was our flight to PHX. Beginning at the gate; we had an ACARS NO COMM message. This did not get corrected until close to departure time requiring a significantly higher workload to accomplish routine items and less time to focus on more critical aspects of our flight. These problems continued off and on throughout our flight to PHX with the last ACARS NO COMM scenario happening within 20 miles of PHX.With our increasing dependence on ACARS for performance and communication; I feel that this issue is becoming more and more of a safety concern. We have no official or approved way to 'reset' ACARS; although Mechanics will sometimes pull circuit breakers or use maintenance functions in the ACARS menu that may sometimes successfully reset ACARS; there is essentially nothing we as pilots can do. Even if we did have a way to effectively reset the system; our ACARS reliability is horrible. Resetting the system takes time and effort when many times that time and effort should be focused on other more pertinent and safety critical tasks. If I am in Central America somewhere and I need ACARS capability for a myriad of possible reasons such as weather/runway change; diversion; passenger issue; fuel issue; customs issue; etc.; the last thing I want to be concerned about is whether or not ACARS will work. If we are moving forward with an ACARS centered philosophy we need an ACARS system that works better than ours currently does. I feel like we are trying to race the Indy 500 in our mom's old Toyota Corolla. It seems like until someone diverts to an airport in Central America without being able to tell anyone and ends up on the ramp with armed law enforcement surrounding our aircraft; followed shortly by a flood of social media posts tagging our company and the incident; nothing is going to be done to fix the problem.Bottom line: ACARS NEEDS TO BE IMPROVED!!! First; ACARS reliability needs significant improvement. We also need an approved way to reset ACARS when required. I feel like; with many other technological aspects; we have been limping this along; band-aiding a much less than adequate system instead of fixing/upgrading it to where it needs to be to support our operation.

Callback: The reporter stated that during flight they often receive a message on the FMC stating 'No Comm' referring to ACARS. When this occurs the flight crews are unable to reset the ACARS by any means. The reporter stated when it's reported to Maintenance that the ACARS is inoperative; a technician comes out and resets a circuit breaker and this often fixes the system; but the flight crews are not allowed to do this in flight. The reporter also stated that very often after they land they receive about a half a dozen messages that they should have received in flight. The reporter stated that flying in areas where radio communication may be a problem (i.e. South America) and perhaps a runway is shut down due to a disabled aircraft or severe weather in the area and they need to divert; an unreliable ACARS not receiving information can be a problem. The reporter stated now that companies are relying more and more on technology that these systems need to be more reliable or at least give the flight crews some sort of method of resetting or rebooting the system without jeopardizing safety.



Synopsis: B737 First Officer reported that he has witnessed a multitude of ACARS reliability issues.