Date: 201907
Flight conditions: IMC
Weather elements / visibility: Thunderstorm; Turbulence
Light: Night
Aircraft: B767-200
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Human factors: Other / Unknown; Communication Breakdown
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence; Inflight Event / Encounter Unstabilized Approach
Detector: Person Flight Crew
When detected: In-flight
Result: General None Reported / Taken
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: Our aircraft descended 200' below ATC assigned altitude. This altitude deviation occurred after Captain announced to me that he was taking over the controls and hence I then assumed the PM (Pilot Monitoring) role. I was listening to the weather for possible changes due to the surrounding thunderstorm when ATC had us descend from FL370 to FL350. I made the 1000 ft to level off call and turned to adjust the volume on the radio. When I turned back; I saw that the aircraft had flew through the assigned altitude and was 200 ft below our assigned altitude. I responded by telling the Capt that we were not assigned anything lower and were assigned FL350. He then turned off the autopilot and by hand; returned us to FL350. Many things transpired leading up to this deviation.The day before; on Saturday; The Capt and I were in ZZZ1. When we got to the aircraft; we found it had several MELs and several people were coming in and out of the cockpit asking questions; (nothing unusual) but it made the Capt become very angry/frustrated to a point where he closed his eyes and clinched both his fist for several seconds. I could see he was very bothered by something (the surroundings). I asked to see some of the paperwork so I could start putting things into the computer and asked if he needed me to help with anything else hoping to help relieve some of his stress. He told me to go do my walk around and I'll give you the paperwork afterward. When I returned I did get paperwork but later I found out that some of the reason for Capt getting enraged was due to me asking for the paperwork in the first place. We had a good flight for the most part till towards the end. In the end there was a lull in the conversation between us so I asked him his opinion on about [the company's scheduling practices]. The Capt once immediately started getting very loud and upset when answering. I tried to talk to him and explain I was simply just chatting but he seemed to get very mad. After talking with him and explaining that the subject had no personal meaning and that it was simply chit chat he did seem to calm down and the flight ended uneventful.The next day (the day of the altitude deviation) we got to the aircraft a little early and everything was uneventful (other than it being extremely hot) we pushed back and taxied to rwy. I was PF (Pilot Flying) and the Capt gave me the controls. I held the brakes; advanced the throttles to 70% N1; waited for them to stabilize and called for N1. The throttles did not evenly advance and I mentioned this to the Capt as he was making hand motions for me to advance the throttles by hand (which made the Capt aggrevated) because an aircraft had been cleared to land on [the parallel runway] but for some reason he thought it was landing [on our runway]. We are rolling down the runway and we rotate and on climb out at around 300-400 ft. I lay my hand on top of the throttles. The Capt reaches over and physically moves my hand and tells me not to do that during that phase of flight. I did not say anything at that point because we were below 1000 ft. AGL. After we above 10;000 ft. I made mention (in a non-aggressive tone) of why I put my hand on the throttles; which is from past experiences; it allows me to feel what the auto-throttles are doing in that phase of flight and I haven't seen in any manual where this isn't allowed but once again the Capt became very riled up. He then told me that he was the Capt and I was just not to do it. After leveling off at cruise I opened my iPad and started to look through the Boeing FCTM and we started some light chit chat about little things in the book. When items were discussed that I didn't 110% agree with him; it would once again set him off and he would start getting loud. These items were centered around technique; not procedure and I was discussing the difference. I then simply stopped talking to him other than work issues related to the flight. During the flight the Capt would make airspeed changes and altitude change request while he was PM and never tell me about them. I would have not been aware of it if I'd not see him do it.At one point the fuel config light came on. I saw there was 1200lbs in the center tanks so I turned them on. The Capt watched me and then he the also turned on the center cross feed and turned off the left pumps because of a 700lbs difference. Once the center tanks got to 400lbs; he turned the pumps off on the center. I kept watching the other pumps that were still running and when the tanks became even; I was going to turn the pumps back on and the cross feed off. The Capt told me that I was the PF and nothing else and then he proceeded then to turn it on. I noticed he was starting to stare at me and I briefly looked over at him and he pointed his finger at me and said 'you and I are going to have a problem.' I took this as a form of intimidation and personal threat. I turned and looked away trying to deescalate the situation and where a conversation may lead if I had asked why. I thought he was now in a strict PF/PM mode so there after ATC radioed and requested we descend from FL390 to FL370 I dialed 390 into the MCP and looked at him to put it into the FMC. He looked at me and I stated this and he then got extremely furious and yelled 'My Control's'. At this time I did not understand what was happening and relieved the controls to the Capt. After the altitude deviation and telling him what the weather was in ZZZ; I tried watching the Capt to figure out where he was at in the descent. Thunderstorms were everywhere and as the lighting flashed I tried to let the Capt know how close we were (on my side to them). When the time came for the landing brief; the Capt never informed of the landing brief. He simply started reading from his iPad. There was no flight control swap and I rushed to pull up the approach plate on my iPad. After he was finished reading; he called for the descent check list. I looked to make a check that everything was complete and noticed that the landing speeds had not been put in and told the Capt of this discrepancy. Soon after we contacted ZZZ approach and was vector to the final. Once pass the FAF; things started to get extremely bumpy and at the 1000 ft; I made the stabilized call but by the 500 ft we were +/- 10-20 kts and a sink rate of 1000 ft. I felt then I should have made a go-around call due to being unstabilized and unsafe. I believe that the Capt would not have acted on my go around call due to how he responded during flight. I assessed that landing at that point would be safer than a go around that would give the Capt another chance to potentially not adhere to my calls.




Synopsis: B767 First Officer reported cockpit communications breakdown between Captain and First Officer which eroded CRM and compromised the safe operation of the aircraft.