Large Transport; Low Wing; 2 Turbojet Eng
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 4.0
Situational Awareness; Distraction; Human-Machine Interface
ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Provided Assistance; Air Traffic Control Separated Traffic
Human Factors; ATC Equipment / Nav Facility / Buildings
During a period of heightened volume and complexity Flight Data removed strips on Aircraft X and neither myself; my Radar Assist; or the adjacent sector realized the aircraft full data block and flight plan were missing for nearly 50 miles.When I arrived at the sector I realized that I had parallel arrivals that needed sequencing. I needed a Radar Assist almost right away and told him the only thing I was really working on at the moment was our two arrivals. I looked back at the scope and only had one aircraft landing. I told him I guessed that I was wrong and only had one arrival. I would have never expected someone else in the building who is not an air traffic controller to remove strips on an active flight that I owned in the middle of my sector. Aircraft X called and said that if we needed him to make his restriction (that is in the next sector) he would need to start down right away. We did not know who Aircraft X was and asked him to say the call sign again. We advised him to standby while we tried to figure out who it was. There were no data blocks for Aircraft X and no flight plans. We asked for his position at which point he indicated he was inside the boundaries of the next sector who did not previously know he was there.This was an extremely unsafe situation that needs to be addressed. An air carrier flew for approximately 50 miles without receiving radar services; at best this an airspace violation; at worst it could have been an IFR to IFR collision. It is absolutely terrifying to think about what could have happened in this situation. We need to be accountable to all of our shareholders; pilots; airlines; and the flying public. The pilot deserves an explanation of why he was forgotten. Flight data apparently said they inadvertently removed strips on the Aircraft X when attempting to remove strips on a duplicate general aviation flight plan. Flight data should not have the ability to edit active flight plans even with logic override. The recovery from this situation would have been smoother if; as part of our recurrent and/or refresher training; controllers who seldom have the opportunity to enter VFR flight plans received training on both starting tracks and entering flight plans.
A flight plan for an active enroute flight was removed from the ATC system. The aircraft's 'full' data block dropped off the Controller's scope and only a partial data block remained on the radar display. The controllers did not notice for approximately 50 miles and did not realize an aircraft was flying through their airspace.