Date: 202006
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Aircraft: Medium Transport; Low Wing; 2 Turbojet Eng
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Climb
Airspace: Class C ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Elevator Trim System
Component problem: Improperly Operated
Reporter organization: Air Carrier
Reporter function: Captain
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Human factors: Human-Machine Interface; Situational Awareness
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Deviation - Altitude Excursion From Assigned Altitude; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew FLC Overrode Automation; Flight Crew Returned To Clearance
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: We were assigned to level off at 14;000 feet. When the 1;000 foot chime sounded; my First Officer stated 'one thousand to go; altitude select.' I verified that ALT SEL was displayed on the FMA. At about 13;400 feet; still in PITCH HOLD; I moved the UP/DN thumbwheel to shallow the climb rate. My guess is that the aircraft went to ALT* while I was adjusting the pitch; which then deselected ALT SEL and reverted to PITCH HOLD; and it went unnoticed. At 14;200 feet we realized that the aircraft had climbed through the selected altitude of 14;000 feet. I quickly pressed ALT; pushed VS with a 700 FPM descent and re selected ALT SEL. The aircraft successfully leveled off at 14;000 feet. In total we deviated from our assigned altitude by 300-400 feet for no more than about 10 seconds. ATC was busy talking to other aircraft and did not mention anything to us; nor did we have a chance to tell them that we had deviated. Adjusting PITCH HOLD within 1;000 feet of level off could result in what happened to us. The lesson I learned is to not do this as it could go unnoticed; resulting in an altitude deviation.


Second narrative: On ZZZ Departure to ZZZ1; climbing to our filed alt of 14;000 with A/P engaged.Passing through 13;000 Pilot Monitoring (First Officer) called 'a thousand to go' at which time the Pilot Flying (Captain) responded appropriately. Pilot Flying then initiated a pitch reduction via the FD adjustment wheel inside of 1;000 [feet] of level off; but did not notice 'ALT SEL' being deselected.Both pilots realized at the same time that the aircraft had not leveled off and was still climbing through 14;200. Pilot Flying immediately called out and pressed 'ALT' to stop the climb; reduced the power slightly to initiate a level off; and then initiated a 700 FPM descent towards 14;000 [feet] using VSI mode. The alt alerter was reverified set at '14;000' and that 'ALT SEL' was displayed. Pilot Flying and Pilot Monitoring noted that the aircraft apexed at 14;400 feet MSL. Aircraft captured the selected altitude (14;000 feet) as expected after the correction was made.Neither the crew nor ATC communicated the altitude overshoot. Sterile flight deck was adhered to in accordance with regulations and policy. TCAS display showed no traffic near the aircraft. No abrupt maneuvers were initiated; and neither passenger safety nor comfort became at risk.Bottom line; like we learned in ground school and the simulator; don't touch nothin' (!!) when you're inside 1;000 feet of capturing an altitude. Plain and simple.Causes/Contributors to deviation: (not excuses - but these are the other things at play)- Both pilots have not flown much since CV-19 crisis begun. The threat of low proficiency was briefed and we agree to take it slow and watch each other's back.- Flight was briefed by First Officer as the Pilot Flying. Captain took the runway when we were CFTO but kept it on the roll. I didn't ask for it back because we didn't need to do a control change on the take off roll.- After the a right turn and continuing the climb to 6;000; ZZZ Departure then directed us to climb to 15;000 feet. Pilot Monitoring (First Officer) responded to ATC and rolled in 15;000' into the alt alerter. Pilot Monitoring noted the difference from the filed altitude and mentioned to Pilot Flying that he/I would confirm with ATC. Prior to calling ZZZ Departure; ATC called us to correct the altitude back to 14;000. Pilot Monitoring immediately reset the alerter to 14;000; and confirmed 'ALT SEL' with Pilot Flying (Captain).- Somewhere in the midst of this correction; the Captain realized he had kept control for the First Officer's (briefed) leg. We decided to leave the Captain as Pilot Flying for the leg at which time the Captain followed the correct procedure for swapping the HSI carat from right (First Officer) to left (Captain).- We were also given a freq change to ZZZ ATC and Pilot Monitoring checked us in. Next came the Pilot Flying reducing the pitch attitude inside 1;000 feet from level off.Slow it down. Confirm changes. No fast hands. Remember [aircraft] gotchas. Prioritize issues and; when able; handle them sequentially versus overlapping and simultaneously.


Synopsis: Air carrier flight crew reported an altitude overshoot which resulted from manually adjusting the pitch during climb.