Date: 201509
Local time of day: 1201-1800
Location: LSZH.Airport, FO
Weather elements / visibility: 5
Light: Daylight
Aircraft: Gulfstream Jet Undifferentiated or Other Model
Operator: Corporate
Operating under: Part 91
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground LSZH
Reporter organization: Corporate
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Human factors: Situational Awareness; Confusion; Distraction
Second reporter function: Pilot Flying; Captain
Anomaly: Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Incursion Taxiway
Detector: Person Air Traffic Control
When detected: Taxi
Result: Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Human Factors; Procedure
Primary problem: Human Factors

Narrative: Taxiing to Runway 32; our aircraft crossed taxiway red light bar on taxiway K located after crossing Runway 28 en-route to Runway 32 (for departure). Red light bar is utilized for sequencing aircraft order for departure (de-ice pads). We were taxiing from parking area 7; (and as per ground instructions following another aircraft). Through 3 previous ground frequency changes; we were instructed to continue to follow an aircraft ahead. At final ground frequency change (4th); I did not immediately tune to next frequency and 'possibly' missed instruction from ground controller to hold and the aircraft continued to taxi across the red bars. My mistake (Pilot Not Flying); by not switching to ground immediately. (There were no other aircraft in the immediate area or any incident potential). At this time; I was heads down at that particular moment; as we had stopped the checklist prior to event (to cross active runway 28); and now continuing with the checklist; I had not noticed the red light bar. As I looked up the controller notified us that we were over the red light bar. Upon switching to the 4th ground control frequency; the controller advised we had crossed the red light bar and he would be required to file a report. The red light bar in this instance is utilized for sequencing purposes only (prior to the runway holding point) and the intent of the controllers was to put another aircraft (to our left down taxiway K) between us and the aircraft ahead (the controller informed us of that). The point where this occurred has 3 de-icing pads (to our left) which merge into one single lane to stage to the runway hold point for departure. The red light bar was on our taxiway (K); just clearing the runway (28). Never was 'safety' impacted as this red light bar is utilized for sequencing; as 4 entries merge into one (deicing area) into the runway hold point (staging area) and are utilized to stagger aircraft for departure. There was no incursion onto a runway or beyond any runway hold points. Lastly; I the Pilot Not Flying; should have switched to ground control immediately after crossing the runway and not have been heads down at that point. I believe this would have prevented the crossing of the red bar by having two pilots' heads up and alert to these visual lighted markings.


Second narrative: Taxiing to Runway 32; our aircraft crossed taxiway red light bar on taxiway K located after crossing Runway 28 en-route to Runway 32 (for departure). Red light bar is utilized for sequencing aircraft order for departure (de-ice pads). We were taxiing from parking area 7; (and as per ground instructions following another aircraft). Through 3 previous ground frequency changes; we were instructed to continue follow aircraft ahead. At final ground frequency change (4th); we did not immediately tune to next frequency and 'possibly' missed instruction from ground controller to hold; notwithstanding this pilot; (the Pilot In Command and Pilot Flying) saw red hold light bar; but contrary to my training and understanding of the requirements; I continued to taxi over the red light bar (when at a minimum; I should have stopped and queried for further instructions). My mistake (solely mine) was being previously instructed to follow the aircraft ahead and not noticing any other aircraft in the immediate area (continued following aircraft ahead). Note: other pilot was heads down at that particular moment; as we had stopped the checklist prior to event (to cross active runway 28); and he was now continuing with the checklist at my request and had not noticed the red light bar. In fact; he never saw it; as he looked up as the controller notified us and we were over the red light bar. Upon switching to the 4th ground control frequency; the controller advised we had crossed the red light bar and he would be required to file a report. The red light bar in this instance is utilized for sequencing purposes only (prior to the runway holding point) and the intent of the controllers was to put another aircraft (approximately '' mile away to our left down taxiway K) between us and the aircraft ahead (the controller informed us of that). The point where this occurred has 3 de-icing pads (to our left) which merge into one single lane to stage to the runway hold point for departure; The red light bar was on our taxiway (K); just clearing the runway (28). Never was 'safety' impacted as this red light bar is utilized for sequencing; as 4 entries merge into one (deicing area) into the runway hold point (staging area) and are utilized to stagger aircraft for departure. There was no incursion onto a runway or beyond any runway hold points. The only recommendation would be for this pilot (me) to follow protocol; regulatory requirements; best practices and company Policy and Procedures; which is to always hold at any red light bar whether cleared across or not. It was incumbent upon me to; at a minimum stop; ask the Pilot Not Flying to query the controller and confirm whether we should have continued (or not) and not to assume or get lulled into previous instructions prior to the event. This error was solely that of the Pilot In Command/Pilot Flying (me).


Synopsis: While taxiing for takeoff; Gulfstream crew had to switch to four different ground controllers. During the final frequency switch the crew crossed a hold line marked with a red light bar. New Controller notified of the error and redirected the crew.