Large Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Flight Crew Type 1609
Communication Breakdown; Situational Awareness; Time Pressure
ATC Issue All Types; Conflict Ground Conflict; Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Incursion Runway
Air Traffic Control Separated Traffic; Flight Crew Took Evasive Action
Human Factors; Procedure
Sitting number one for takeoff while holding short of Rwy 03R in MPTO; we believed we heard in very broken English 'line up and wait 03R; be ready for an immediate'. I saw Aircraft Y approaching and thought it will be tight but doable. I responded to ATC with 'Line up and wait 03R; and we'll be ready'. Practically all the ATC communications were in Spanish; except for our clearance. This makes it very difficult to have situational awareness. We heard an ATC transmission while we were taking the runway in Spanish that included '[our company callsign]' and had intensity in his voice (I can only assume this was the Aircraft Y pilot asking what the heck was going on with [our company callsign] taking the runway). Then ATC said something that seemed like a takeoff clearance. At this time the Captain was straightening the aircraft onto the runway centerline. I asked ATC 'say again.' There was no immediate response so the Captain keyed the mic and said 'confirm cleared for takeoff.' We both heard 'affirmative.' We proceeded with the takeoff roll. I was flying pilot and the Captain was non flying pilot. While we were on the takeoff roll we heard in Spanish 'Aircraft Y... [unintelligible]... Going around.' Once we got in the air around 800 ft AGL; ATC told us that our instruction was to 'line up and wait after landing traffic and be ready for immediate.' The Captain responded that we did not hear the 'after landing traffic' portion. Since we did not hear that I never responded when I accepted the lineup and wait clearance. I read it back and ATC had that opportunity to correct the situation before we took the runway. Also; why did we hear 'affirmative' after the Captain asked to 'confirm cleared for takeoff'? I believe the majority of the transmissions in Spanish played a large role in this event due to not giving us complete situational awareness. Also the controller's English was very poor and they spoke fast making it difficult to understand. I personally feel that ATC made a mistake and was trying to put the blame on us after their bad decision to issue us a takeoff clearance.
Air carrier First Officer reported communication breakdown with ATC regarding takeoff clearance from MPTO.