Date: 202003
Local time of day: 0601-1200
Location: ZZZ.TRACON, US
Flight conditions: VMC
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Flight plan: IFR
Flight phase: Climb
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness; Confusion; Distraction
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Overcame Equipment Problem
Contributing factors: Environment - Non Weather Related; Human Factors; Procedure
Primary problem: Human Factors

Narrative: On climbout from ZZZ; at approximately 13;300 feet the Cabin Altitude Warning horn sounded and the Cabin Warning light illuminated. As the PF; I immediately disengaged the autothrottles; began to level off and informed the FO that 'I had the radios.' I then called ATC and told them I needed to level off and requested a slight descent back to 13;000 feet and that 'I would get back with them.' The descent to 13;000 was granted and I had the FO set 13;000 feet in the MCP (it had been set to 30;000 feet as this was our last clearance). FO immediately identified the issue that the packs were both in the OFF position. He turned them on. ATC asked if we needed assistance and I said no. We flew at 13;000 feet for approximately 2 or 3 minutes while the packs pressurized the cabin and the cabin began to descend. FO had previously silenced the warning horn. When the cabin descended below 10;000 feet the Cabin Warning light extinguished. I asked FO to call back to the cabin and ask if any O2 masks had deployed. None had. When the cabin was descended; I communicated with ATC that we were ready to accept a climb. ATC asked if I could tell them what the issue had been. I replied (paraphrasing) that; 'We had a configuration issue with the cabin pressurization; and that we had fixed it and were good to go.' For this issue to occur there were basically four [causes] - 1. On my (CA) preflight; I failed to notice that the packs were off. 2. On taxi out during the Before Takeoff Checklist; I always look over and verify the pressurization switches. I did this here as well; but again; failed to notice the packs were off. 3. FO failed to notice the packs in the off position and position them correctly on the Before Takeoff Checklist. 4. PM (FO) failed to notice the packs were in the off position on the After Takeoff Checklist.After we had corrected everything and were climbing out again; we discussed what happened briefly (we needed to compartmentalize as this was a short flight to ZZZ1 and we had 'bigger fish to fry' than to get caught up about what happened). However; the FO mentioned something like 'I must have looked up there like 5 times'.This was a case on both our parts of LOOKING but not SEEING. And THAT is a classic tell-tale sign of fatigue. Yes; it was a short taxi to Runway XL in ZZZ but I felt (and FO agreed after) that we were not too rushed and were ready to go. The fatigue was a factor of: a) a longish day coming out of ZZZZ and then having to run through customs hall (came into Gate X); get on bus over to Terminal X; both get 'random' going through KCM; [Known Crew Member] and then finally getting to our Gate (X; I think). We actually got to our gate with plenty of time; but all that I guessed contributed a bit to feeling 'stressed.' B) It is hard to say what impact all of the ongoing Coronavirus 'stresses'; are doing. We did a great job all trip of compartmentalizing these issues (my FO is not even off probation; so definitely feeling stressed). There was no direct stress from all this COVID-19 stuff; but I believe there is a 'cumulative' day-after-day buildup of stress (almost like water torture...drip; drip; drip). How much of it adds up and causes one to feel anxious or stressed is hard to say but I believe it does contribute to a feeling of feeling a little tired and exhausted no matter how much sleep we got the previous night.On the upside; we both know that that will never happen to us again but it is disappointing how many 'misses' there were that led to this. We also handled it well when it happened. I immediately arrested our climb and ensured there wasn't going to be a 'rubber jungle.' My FO dealt with the packs issue and kept his composure. We exercised good CRM and a division of duties and then both quickly got back to the flight which was short where many things are happening quickly.


Second narrative: On the second day of our pairing; during the second leg from ZZZ to ZZZ1; both the CA and FO completed normal preflight duties; to include all checklists from Pre-flight through Before Takeoff per SOP. We received a short taxi between the gate and runway; although we completed all checklists as normal prior to accepting takeoff clearance. CA was Pilot Flying; I was Pilot Monitoring. The Control Tower asked if we needed more time prior to takeoff due to a short taxi; but as we completed all checklists; we both agreed that we were ready for departure. Takeoff and initial climb out was uneventful. The PF was hand-flying; and called for configuration clean-up and After Takeoff checklists per SOP. As PM; I completed each per SOP. After checking into Departure ATC; and receiving climb clearance to Flight level 300; the Cabin Altitude warning light illuminated along with the aural horn at approximately 13;300 feet. The PF immediately verbalized and executed a level-off; said 'I have the radios'; as I scanned the pressurization panel to diagnose the malfunction. The PF immediately notified ATC that we were leveling-off; requested to descend and temporarily maintain 13;000 feet; and engaged Autopilot A while verbalizing it. ATC approved that request. Simultaneously; I recognized that both Engine Bleed Air Valve switches were in the 'off' position. I verbalized that both were off; and immediately switched both Engine Bleed Air Valves to 'on'. I also verified that both Pack Switches were currently in the 'on' position; with the Shut-off Valve in the 'Auto' position. (Only the Bleed Air Valve Switches were in the wrong position for the phase of flight.) I then silenced the Cabin Altitude Warning Horn. The PF asked; 'What is the cabin altitude and was the cabin pressurizing?'...I responded that the cabin indicated approx. 10;500 feet ...and after approximately one minute; that the cabin altitude gauge displayed a descent of approx. 1;000 FT/min. Once the cabin was below 10;000 feet PA; the Cabin Altitude Warning light extinguished; and the cabin continued to pressurize to the appropriate altitude. I reported all of this to the PF.After confirming with the PF that our Bleed/Pack configuration was correct; the PF notified ATC that our configuration issue was fixed; and that we could continue our climb. The PF directed me to confirm with our FAs that the cabin oxygen masks did not deploy. I then used the Cabin call button and spoke to the FM; confirming that no masks deployed and the cabin was properly configured. I notified the PF that the cabin was 'Ok; with no masks.' The Cabin Crew was unaware of the event. (Due to the short 1 hour flight; the CA debriefed the Cabin Crew of the event after we landed and de-planed). The CA and myself did a quick de-brief upon reaching cruise. Although we had completed all checklists per SOP; neither of us noticed that both Bleed Valve switches were off. As neither of us believed we moved the Bleed Air switches; we determined that they must have been in the 'off' position since before we entered the aircraft; quite possibly from the prior crew completing a Termination Checklist. Although I read all the checklists; I missed that these switches were in the 'off' position. The entire event occurred in only 2-3 minutes; from Cabin Altitude Warning to proper configuration and cabin pressurization. As a crew; we were in the 9th hour of our crew day; it was late in the evening; and we both felt that fatigue could have been a cause of our missing of the switch positions. Additionally; during routine operations; the Bleed Air switches are normally left in the 'on' position; as the aircraft are normally turning into another pairing. I have not personally experienced many flights where I had to turn on the Engine Bleed Valves. A long crew day; and my greater focus on the pack switch positions during pre-flight; resulted; surprisingly; in my missing the position of the Bleeds.


Synopsis: Air carrier flight crew reported having an aircraft pressurization problem thinking it was an equipment problem but the Packs were not turned on.