Flight crew reported passengers boarded the aircraft with alcohol. The crew reported confusion with ramp control during push back about potential conflicting push back traffic. The crew reported difficulty completing pre takeoff checklists due to several Ramp Control and ATC taxi instructions during a busy departure period at the airport. The crew reported another taxiing aircraft had its landing lights on making it difficult to see the taxiway markings. The crew utilized the wrong Tower frequency causing them to miss their clearance to taxi onto the runway.

Reporter 1

[Date], Aircraft X CLT/ZZZ, Scheduled XA:30 UTC. At the Gate 1) During passenger boarding. a. Lead F/A (Flight Attendant) was given a safety brief. Included with the brief was a request to maintain good communication with the flight crew on any matters. Further, instruction was given to the Lead F/A to step back from any passenger problems while at the gate and engage the Gate Agent to handle the passenger problem. b. Near the completion of boarding the Lead F/A came to the flight deck to inform the crew that two passengers boarded the aircraft with alcohol. Passengers were engaged by another flight attendant, not the Lead, and denied that they had alcohol. Lead F/A advised that the alcohol beverages had spilled. Flight crew and Lead F/A agreed to a plan to resolve the matter. Passengers complied with instructions and remained onboard. 2) During Push Back from Gate X a. Flight crew worked through preflight preparations, including a review of performance data for [Runways] 18C and 18L. During FMC programming flight crew determined that a new [set of performance data] had been generated removing data for 18L, the most probable runway for departure. New performance data was updated via ACARS for 18L and was reviewed by the flight crew and programmed into the FMC. MEL XX-XX was reviewed. All other preflight preparations were completed per company policies, procedures and flows. Load close-out was received at the gate b. Flight crew called Ramp [name] for a clearance from Gate X and received clearance to push back. Ground crew declined to push the aircraft from Gate X due to conflict with aircraft in the ramp alley. First Officer discussed the push clearance with Ramp [name] and was assured the clearance to push was valid and that aircraft were not in conflict as the other aircraft were from the adjacent concourse. Ground crew was advised and still refused to push the aircraft. Another inquiry was made to Ramp [name] and push clearance was rescinded. c. Conflict aircraft from adjacent concourse departed the ramp. Ramp [name] re-cleared the aircraft to push from [Gate] X. Ground crew complied with the push back clearance. Two engines were started in the ramp alley. Ground crew received a wave off/salute. After start flows and checklist were accomplished. Out time XB:31 local/XA:31 UTC. d. Captain and First Officer used headsets and discussed abnormally high side tone volume on the INT function with MIC selected. Various adjustments were made to set appropriate communication volume 3) Taxi from Gate X to Runway 18L a. First Officer issued a request to taxi. Ramp [name] issued a multiple part clearance. (Taxi south line, Spot XXS, caution for pushback on [neighboring gate], contact Ramp East 129.225 at Spot XXS). The clearance from Ramp [name] clearance was given rapidly and muffled. A second request was made for a taxi clearance/confirmation. Clearance was heard and understood by both crew members. Aircraft proceeded to XXS. b. Approaching XXS, First Officer contacted Ramp [name2]. Ramp [name 2] responded with a clearance to taxi to [Spot] XXS and contact Ground at [spot] XXS. Captain verbally reviewed triggers with First Officer for Before Take Off Flow and advised that a flight control check would commence on Taxiway C. Approaching [spot] XXS Ground Control issued a clearance to taxi [Taxiways] Mike, Charlie, hold short C10 for [Runway] 18L. First Officer replied to Ground Control and Captain responded to the First Officer repeating the clearance with emphasis to Hold Short of C10. The taxi route was continuous without stops or delays. Numerous aircraft were on Taxiway C and positioned at various ramp location spots adjacent and parallel too Taxiway C. Two aircraft were positioned facing south at Spot XYE. The aft positioned aircraft at XYE had its landing/taxi lights illuminated while stationary. c. Flight control checks were initiated on Taxiway C prior to C10. During the initiation of the elevator check as the First Officer was verbalizing elevator position, Ground Control re-issued the taxi clearance to hold short of [Taxiway] C11. Flight control checks were discontinued, the taxi clearance was accepted and responded too by the First Officer. The Captain repeated and verbalized the clearance to the First Officer with emphasis to hold short of C11. Flight Control checks were re-initiated by the Captain. At full aft elevator the First Officer verbalized the elevator position simultaneously as Ground Control re-issued a clearance to continue to [Runway] 18L. The First Officer read back the clearance. The Captain repeated the clearance to the First Officer. The Captain maintained full aft elevator during the communication with Ground Control and the First Officer. d. Flight control checks re-initiated from the beginning of the Before Take Off Flow and the remaining flow items were completed. The taxi/landing lights from the aft aircraft at [Spot] XYE were obscuring the view on Taxiway C. The Captain stopped the aircraft in a position on Taxiway C that used the forward aircraft's wing at Spot XYE to block the glare from the aft aircraft at Spot XYE. The Captain gave a courtesy flash of the taxi light to alert the crew of the aircraft on XYE of their landing/taxi light illumination. The First Officer verbalized and switched Radio One to the Tower Control frequency. The parking brake was set. The Captain called for the Before Take Off checklist. Task Loading increased due to a reduced time factor in the task/time equation. Flight crew members were in the green area of the [threat mode], however external factors were compressing the time component and additional time elements would be required to remain out of the yellow and in the green area of the threat mode paradigm. e. As the Before Take Off checklist was being accomplished the aircraft on [Taxiway] C12 was cleared on to [Runway] 18L, however no clearance was heard on the radio. At this time both the Captain and the First Officer deduced that an incorrect frequency was selected on Radio One. The error was trapped and corrected. The flight crew was now in the yellow area of the threat mode paradigm due to a high task load environment. f. Upon tuning of the Tower frequency, the crew re-initiated the Before Take Off Checklist. Simultaneously the Tower Controller issued a clearance to proceed onto the runaway. The Tower Controller's voice conveyed a tone of agitation, immediacy, anger and frustration. Additionally, the Tower Controllers diction was rapid, difficult to hear and understand. For reasons of safety, the crew declined the clearance. The flight crew again attempted to complete the Before Take Off Checklist. The Tower Controller responded with agitation and another clearance that was rapid and difficult to understand with a demand to expedite taxi onto the runway and in some manner exit the runway. We advised the Tower we would need 30 seconds and we would be ready for departure. The Tower Controller responded again with agitation and anger and demanded we taxi onto the active runway in an expedited manner, with a rapid diction pattern and clearance that we were unable to understand while an aircraft was approaching the runway for landing as we were being lambasted by the Tower Controller regarding other traffic waiting to depart. g. At this point the demands from the Tower Controller had compromised the safe operation of the aircraft as the issued clearances appeared too no longer be operationally motivated. The Captain momentarily took over radio communication and advised the tower that we were unable to accept the clearance. Our decision to not move the aircraft was driven by safety concerns and based on the threat mode model. The true safest course of action was to keep the aircraft stationary until the task loading paradigm could be shifted to normal operational expectations. h. The Tower Controller remained agitated and instructed the crew to copy a telephone number and demanded a call to the number. The Tower Controller read the number, we advised that we received the number and the Tower Controller re-read the number a second time and got a digit incorrect in the second reading and self-corrected their error of the telephone number. We confirmed receipt. The Before Take Off Checklist was completed, and we advised the Tower Controller we were ready for departure. The CLT airport during this bank of flights and the previous bank of flights was a chaotic mess, as is the case with CLT with all banks of flights. Aircraft crew transiting into an out of the 1 and 2 concourse are subject to extraordinary delays and the resultant increase in stress as are the Ramp Controllers and local ATC controllers. This high level of stress with too many aircraft movements in too small of space is a significant negative factor in the safety equation. The attempts by airlines to operate in this manner is a contributing factor to the degradation of safety and the stress applied to all personnel is a concrete byproduct of this poor planning and management. Further, the manifest stress is evident in the voice, demeanor and diction of ATC and other personnel which results in a degrade performance profile. Reduce access and aircraft movements in the 1 and 2 concourses to better manage traffic flow. Properly staff and monitor ATC positions and personnel for signs of stress. Review and stream line CLT Ramp operations and coordination with ATC Ground Control.

Reporter 2

1. During passenger boarding. Lead F/A (Flight Attendant) was given a safety brief. Included with the brief was a request to maintain good communication with the flight crew on any matters. Further, instruction was given to the Lead F/A to step back from any passenger problems while at the gate and engage the Gate Agent to handle the passenger problem. Near the completion of boarding the Lead F/A came to the flight deck to inform the crew that two passengers boarded the aircraft with alcohol. Passengers were engaged by another flight attendant, not the Lead, and denied that they had alcohol. Lead F/A advised that the alcohol beverages had spilled. Flight crew and Lead F/A agreed to a plan to resolve the matter. Passengers complied with instructions and remained onboard. 2. During Push Back from Gate X Flight crew worked through preflight preparations, including a review of performance data for [Runways] 18C and 18L. During FMC programming flight crew determined that a new [set of performance data] had been generated removing data for 18L, the most probable runway for departure. New performance data was updated via ACARS for 18L and was reviewed by the flight crew and programmed into the FMC. MEL was reviewed. All other preflight preparations were completed per company policies, procedures and flows. Load close-out was received at the gate. Flight crew called Ramp [name] for a clearance from Gate X and received clearance to push back. Ground crew declined to push the aircraft from Gate X due to conflict with aircraft in the ramp alley. First Officer discussed the push clearance with Ramp [name] and was assured the clearance to push was valid and that aircraft were not in conflict as the other aircraft were from the adjacent concourse. Ground crew was advised and still refused to push the aircraft. Another inquiry was made to Ramp [name] and push clearance was rescinded. Conflict aircraft from adjacent concourse departed the ramp. Ramp [name] re-cleared the aircraft to push from [Gate] X. Ground crew complied with the push back clearance. Two engines were started in the ramp alley. Ground crew received a wave off/salute. After start flows and checklist were accomplished. Out time XB:31 local/XA:31 UTC. Captain and First Officer used headsets and discussed abnormally high side tone volume on the INT function with MIC selected. Various adjustments were made to set appropriate communication volume. 3. Taxi from Gate X to Runway 18L First Officer issued a request to taxi. Ramp [name] issued a multiple part clearance. (Taxi south line, Spot XXS, caution for pushback on neighboring gate, contact Ramp [name 2] 129.225 at Spot XXS). The clearance from Ramp [name] clearance was given rapidly and muffled. A second request was made for a taxi clearance/confirmation. Clearance was heard and understood by both crew members. Aircraft proceeded to XXS. Approaching XXS, First Officer contacted Ramp [name2]. Ramp [name 2] responded with a clearance to taxi to [Spot] YYS and contact Ground at YYS. Captain verbally reviewed triggers with First Officer for Before Take Off Flow and advised that a flight control check would commence on Taxiway C. Approaching YYS Ground Control issued a clearance to taxi [Taxiways] Mike, Charlie, hold short C10 for [Runway] 18L. First Officer replied to Ground Control and Captain responded to the First Officer repeating the clearance with emphasis to Hold Short of C10. The taxi route was continuous without stops or delays. Numerous aircraft were on Taxiway C and positioned at various ramp location spots adjacent and parallel too Taxiway C. Two aircraft were positioned facing south at Spot XYE. The aft positioned aircraft at XYE had its landing/taxi lights illuminated while stationary. Flight control checks were initiated on Taxiway C prior to C10. During the initiation of the elevator check as the First Officer was verbalizing elevator position, Ground Control re-issued the taxi clearance to hold short of [Taxiway] C11. Flight control checks were discontinued, the taxi clearance was accepted and responded too by the First Officer. The Captain repeated and verbalized the clearance to the First Officer with emphasis to hold short of C11. Flight control checks were re-initiated by the Captain. At full aft elevator the First Officer verbalized the elevator position simultaneously as Ground Control re-issued a clearance to continue to 18L.The First Officer read back the clearance. The Captain repeated the clearance to the First Officer. The Captain maintained full aft elevator during the communication with Ground Control and the First Officer. Flight Control checks re-initiated from the beginning of the Before Take Off Flow and the remaining flow items were completed. The taxi/landing lights from the aft aircraft at XYE were obscuring the view on Taxiway C. The Captain stopped the aircraft in a position on taxiway C that used the forward aircraft's wing at Spot XYE to block the glare from the aft aircraft at Spot XYE. The Captain gave a courtesy flash of the taxi light to alert the crew of the aircraft on XYE of their landing/taxi light illumination. The First Officer verbalized and switched Radio One to the Tower Control frequency. The Parking Brake was set. The Captain called for the Before Take Off checklist. Task Loading increased due to a reduced time factor in the task/time equation. Flight Crew members were in the green area of the threat mode model, however external factors were compressing the time component and additional time elements would be required to remain out of the yellow and in the green area of the threat mode paradigm. As the Before Take Off checklist was being accomplished the aircraft on [Taxiway] C12 was cleared on to 18L, however no clearance was heard on the radio. At this time both the Captain and the First Officer deduced that an incorrect frequency was selected on Radio One. The error was trapped and corrected. The flight crew was now in the yellow area of the threat mode paradigm due to a high task load environment. Upon tuning of the Tower frequency, the crew re- initiated the Before Take Off Checklist. Simultaneously the Tower Controller issued a clearance to proceed onto the runaway. The Tower Controllers voice conveyed a tone of agitation, immediacy, anger and frustration. Additionally, the Tower Controllers diction was rapid, difficult to hear and understand. For reasons of safety, the crew declined the clearance. The Flight crew again attempted to complete the Before Take Off Checklist. The Tower Controller responded with agitation and another clearance that was rapid and difficult to understand with a demand to expedite taxi onto the runway and in some manner exit the runway. We advised the Tower we would need 30 seconds and we would be ready for departure. The Tower Controller responded again with agitation and anger and demanded we taxi onto the active runway in an expedited manner, with a rapid diction pattern and clearance that we were unable to understand while an aircraft was approaching the runway for landing as we were being lambasted by the Tower Controller regarding other traffic waiting to depart. At this point the demands from the Tower Controller had compromised the safe operation of the aircraft as the issued clearances appeared too no longer be operationally motivated. The Captain momentarily took over radio communication and advised the tower that we were unable to accept the clearance. Our decision to not move the aircraft was driven by safety concerns and based on the threat mode model. The true safest course of action was to keep the aircraft stationary until the task loading paradigm could be shifted to normal operational expectations. The Tower Controller remained agitated and instructed the crew to copy a telephone number and demanded a call to the number. The Tower Controller read the number, we advised that we received the number and the Tower Controller re-read the number a second time and got a digit incorrect in the second reading and self-corrected their error of the telephone number. We confirmed receipt. The Before Take Off Checklist was completed, and we advised the Tower Controller we were ready for departure. The sequential style ([Spots] S, YYS, hold short [Taxiways] C10, hold short C11, continue full length, etc) of the taxi instructions from the gate to Runway 18L required several communications from ATC/Ramp Control to our aircraft. This lead to interruptions in our checklists, flows, and SOPs. Perhaps we should complete the "before takeoff flow" and before takeoff checklist in the ramp area when using 18L. Although CLT Ramp is not going to like that. Also the ATC Tower Controller should sit jumpseat when we are using 18L to observe the task saturation. I personally need to ensure correct frequencies into #1 Comm during preflight, I mixed up ZZZ Tower with CLT Tower (118.1).