Narrative:

[Aircraft] had right bleed sov (shut off valve) deferred for repeated envir fail in flight; reference 21 in MEL. I reviewed [maintenance logbook]; saw writeup; saw corrective action. [Maintenance logbook] had second MEL sticker (text of 'right bleed sov') taped to front to place in aircraft to match the MEL notification sticker on the [maintenance logbook]. In aircraft I reviewed procedure; which required placing both bleed air valve switches in the off position before engine start and testing for airflow. After reviewing procedure with my trainee; I placed the MEL sticker ('right bleed sov') over the operative bleed valve; the left valve; and did not catch my error. In flight; when we selected the bleed valve that did not have the MEL sticker over it; we were selecting the inoperative valve; and when a right envir fail annunciator on the master warning panel; my trainee followed the proper memory items and backed it up with the checklist. We did not review the [maintenance logbook] or look at the sticker because the failure happened in the terminal area and I immediately became concerned about whether maintenance to correct the problem would be available in ZZZ1. I called ops and requested maintenance and specifically asked whether we should continue or return to ZZZ for corrective action.at no time did I declare an emergency; since there was no indication that we had a failure more extensive than a faulty bleed air system. We were below 10;000 feet; in VFR conditions; and had two crew. At several points I emphasized to ATC that we were not in an emergency situation; that it was a precautionary return for a bleed air failure.once we had run the checklist; I believed we had performed the correct actions to deal with the immediate problem and was seeking a solution that minimized the chance of a complete service failure. I discovered my error after landing; when I examined the logbook while filling out a squawk. At that time; I realized I had placed the sticker over the wrong bleed valve and the incident was not caused by a mechanical failure on the aircraft.maintenance did a quick check of the eva lines in the aircraft; signed off the squawk I had placed in the logbook; and we launched for ZZZ1 with all possible speed. Due to a delayed jet; the delay caused by my error was reduced. I offered several suggestions to dispatch to reduce the impact of my error; including possible duty time effects for the other 1900 crew in the evening. Cargo was delivered and both crews were able to land before running out of duty time and causing follow-on effects for the evening return leg.this was pilot error; there was no real systemic; procedural; or policy issues- I placed the sticker in the wrong place and once in flight; allowed my trainee to exercise his skills in responding to the master warning. The best corrective action I can suggest is that I will carefully review affected systems and sticker placement in the future; as well as taking time to review [maintenance logbook] entries in-flight if conditions allow it to be done safely. In this case; with a second pilot on board to handle flying duties; that would have been a safe course of action.I jumped to seeking corrective action without a careful review of all available information in a situation where doing so would not have compromised safety. In the future I will perform such a review once the immediate problem has been dealt with and the aircraft is properly configured.

Google
 

Original NASA ASRS Text

Title: B1900 Captain reported mistakenly placing an MEL sticker over the operative bleed valve switch resulting in an inability to pressurize the aircraft.

Narrative: [Aircraft] had right bleed SOV (shut off valve) deferred for repeated ENVIR FAIL in flight; reference 21 in MEL. I reviewed [maintenance logbook]; saw writeup; saw corrective action. [Maintenance logbook] had second MEL sticker (text of 'R Bleed SOV') taped to front to place in aircraft to match the MEL notification sticker on the [maintenance logbook]. In aircraft I reviewed procedure; which required placing both bleed air valve switches in the OFF position before engine start and testing for airflow. After reviewing procedure with my trainee; I placed the MEL sticker ('R Bleed SOV') over the OPERATIVE bleed valve; the LEFT valve; and did not catch my error. In flight; when we selected the bleed valve that did NOT have the MEL sticker over it; we were selecting the INOPERATIVE valve; and when a R ENVIR FAIL annunciator on the Master Warning panel; my trainee followed the proper memory items and backed it up with the checklist. We did not review the [maintenance logbook] or look at the sticker because the failure happened in the terminal area and I immediately became concerned about whether maintenance to correct the problem would be available in ZZZ1. I called Ops and requested Maintenance and specifically asked whether we should continue or return to ZZZ for corrective action.At no time did I declare an emergency; since there was no indication that we had a failure more extensive than a faulty bleed air system. We were below 10;000 feet; in VFR conditions; and had two crew. At several points I emphasized to ATC that we were not in an emergency situation; that it was a precautionary return for a bleed air failure.Once we had run the checklist; I believed we had performed the correct actions to deal with the immediate problem and was seeking a solution that minimized the chance of a complete service failure. I discovered my error after landing; when I examined the logbook while filling out a squawk. At that time; I realized I had placed the sticker over the wrong bleed valve and the incident was not caused by a mechanical failure on the aircraft.Maintenance did a quick check of the EVA lines in the aircraft; signed off the squawk I had placed in the logbook; and we launched for ZZZ1 with all possible speed. Due to a delayed jet; the delay caused by my error was reduced. I offered several suggestions to Dispatch to reduce the impact of my error; including possible duty time effects for the other 1900 crew in the evening. Cargo was delivered and both crews were able to land before running out of duty time and causing follow-on effects for the evening return leg.This was pilot error; there was no real systemic; procedural; or policy issues- I placed the sticker in the wrong place and once in flight; allowed my trainee to exercise his skills in responding to the Master Warning. The best corrective action I can suggest is that I will carefully review affected systems and sticker placement in the future; as well as taking time to review [maintenance logbook] entries in-flight IF conditions allow it to be done safely. In this case; with a second pilot on board to handle flying duties; that would have been a safe course of action.I jumped to seeking corrective action without a careful review of all available information in a situation where doing so would not have compromised safety. In the future I will perform such a review once the immediate problem has been dealt with and the aircraft is properly configured.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.