Date: 201710
Local time of day: 1801-2400
Location: HNL.Airport, HI
Flight conditions: VMC
Light: Night
Aircraft: B737 Next Generation Undifferentiated
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Takeoff / Launch
ATC / advisory: Tower HNL
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown; Human-Machine Interface; Time Pressure
Second reporter function: First Officer; Pilot Flying
Anomaly: ATC Issue All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Weight And Balance; Ground Event / Encounter Ground Strike - Aircraft
Detector: Person Flight Attendant; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Returned To Departure Airport
Contributing factors: Human Factors; Procedure
Primary problem: Human Factors

Narrative: We were late off the gate due to the boarding process and then we encountered multiple errors during taxi out while trying to gather takeoff numbers. We tried to determine which issue was the culprit but could not get problem resolved. While holding short of runway 8L at RB we informed ATC we needed a minute. I used my cell phone to call dispatcher and he read me the numbers for our flight. He mentioned there was something on his end that was holding up the numbers. He also sent me the numbers via ACARS which printed automatically. They read assume weight 140;700 (red flag); assume temp. 61C; EPR 91.2; V speeds 148-149-154. In haste we pressed on trying to get back on schedule and missed the RED FLAG threat of the wrong weight which was a 40;000 lb difference; our actual takeoff weight was 180;000. Obvious to us after action but blind to us in the moment of trying to get back our time lost loading and during the error problem.During the takeoff roll the aircraft was sluggish in accelerating and took excessive time to Vr. FO rotated to 9.8 (via pitch angle report) and slightly scraped the tail. I initially felt like it was a possibility but was not 100% sure and did not mention anything at that moment as we were climbing out facing the mountains directly ahead. After accelerating and the initial climb. Our attention started to be saturated with ETOPS information and ATC communication.  The Lead Flight attendant called the flight deck and I answered she told me the aft galley attendants heard an audible scraping sound during lift off under their feet. This confirmed my suspicions of a tail strike.  We continued the climb as we reassessed our thoughts on the matter. FO looked up Tail Strike in the manual and this lead him to the QRH which stated do not pressurize (we were already pressurized) so I looked at the gauges and made sure that that was not an additional problem and decided to leave the pressurization alone at that time. The QRH says to land at nearest suitable airport so I told ATC we needed to return to HNL and let him know our problem and that it was not currently an emergency. I contacted Dispatch and Maintenance Control to let them know and also to decide what to do about overweight landing. I asked FO to handle the radios and ask for a hold to burn fuel while I talked to Dispatch; Maintenance Control; FAs; passengers; and station. During that time ATC gave us hold as published at (they claim) BAMBO intersection and FO read back CKH (Koko head) I had my attention diverted in conversation with Dispatch and Maintenance Control at the moment of the clearance. As we leveled and started to get to the holding fix I was trying to find the published fix on the low enroute and said something is wrong here I asked FO the clearance again and just as I did ATC asked us 'how much more time on our heading?' I responded we were entering the hold at CKH and asked him to verify that's where he wanted us to hold and he said the original clearance was BAMBO but that holding at CKH was approved so we continued. After that communication I continued with Maintenance Control and Dispatch they said they'd rather us land and write up the overweight landing so we asked for vectors for the approach. We landed without incident.Maintenance assessed the write up and noted that it was a slight scrape and that they were able to differ the paint on the skid and that the green/red sticker was not damaged therefore the skid was not crushed or depressed. They also did an overweight inspection and we gathered a new release and fueled up then continued without issue.


Second narrative: [Report narrative contained no additional information.]


Synopsis: B737NG flight crew reported returning to the departure airport due to a tail strike on takeoff.