Date: 201706
Location: ZZZ.Airport, US
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Parked
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; First Officer
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness
Second reporter function: Pilot Flying; Captain
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Other Person
When detected: Aircraft In Service At Gate
Result: Flight Crew Became Reoriented
Contributing factors: Human Factors; Manuals
Primary problem: Manuals

Narrative: Approximately 15 minutes after the completion of our flight; the FAA Safety Inspector who had been riding in the cabin; barged into the cockpit unannounced; uninvited; and blurted out in a stern voice; 'This flight is in violation of FAR 121.xxx.xx.xx...!' Meanwhile; my Captain was on the phone with Maintenance and was doing his best to hear what the Mechanic was telling him to do with the two Maintenance write-ups which had occurred during the cruise portion of the flight. The Captain asked him to kindly wait until he finished speaking with Maintenance and so he waited until he had finished; obviously not realizing he was on the phone. Oops!The Inspector proceeded to explain that neither the Pilots nor the Flight Attendants had made a PA upon turning off the seatbelt sign. The Captain informed him that we had been dealing with two separate mechanical issues at the time and had elected not to make the PA; but rather focus on the more important maintenance issues. The inspector informed us that truly it is at our DISCRETION; however; one of the Flight Attendants was then responsible for making the PA and that they had not done so. He continued by stating that he was aware of the LACK of this requirement in the Flight Attendant manual and that he intended on getting that changed. I will refrain from making comments about the Inspectors lack of professionalism in handling this matter and just say it should have been handled differently.As far as the possible violation of an FAR goes; if the FAA Inspector is correct then YES; there needs to be an amendment made to the Flight Attendant Manual. As far as the Inspectors handling of the situation; I will have to bite my tongue.


Second narrative: After arriving at the gate I was met by the Crew and an FAA Cabin Inspector. He introduced himself and informed me he was doing an inspection in the cabin. I briefed the FAs and continued with our preflight. During our short flight we were in the climb and it was light chop; seatbelt sight on. During this time we get an R2 window overheat. We ran the checklist and it wouldn't go away. We leveled at cruise and the FO started to send Dispatch a message about the R2 window. When he hit send his MCDU went blank. It stopped working. We were getting busy looking for frequencies to contact Dispatch to let Maintenance Control know. At about that time the flight smoothed out. We were busy talking with Dispatch and Maintenance Control that I just reached up and turned the seatbelt sign off for a few minutes before we began our descent as we are getting close to the TOD. When we arrived at the gate I was on the phone with Maintenance Control deferring the two maintenance issues when the FAA Inspector stepped in the cockpit and started telling me I was in violation of FAR 121. I had to tell him to hang on until I got done with Maintenance. He stated that I didn't make an announcement when I turned the seatbelt sign off. I told him I was dealing with the Maintenance issues. He then began to tell me that there's a discrepancy between our Flight Operations Manaual and Flight Attendants Manual. He then took down my information from my license and medical and told me I needed to fill out a report.


Synopsis: B737 flight crew reported being chastised by an FAA inspector post-flight for not making a standard announcement when the seat belt sign was turned off in cruise.