Narrative:

I checked in with tower on the ILS 03R. They said 'continue 03R'. I had trouble understanding the controller and said 'understand cleared to land 3R?' they said 'negative; continue for 3R'. I acknowledged the 'continue.' there was a lot of communications in two different languages and the english was challenging to understand. Approaching 1000 feet we were fully configured; landing checklist complete. I had not heard a landing clearance; and had not acknowledged a landing clearance. I noticed the preceding aircraft had cleared the runway. During the 1000 foot call we set missed approach altitude and emphasized internally we hadn't thought we'd received a landing clearance. I tried several times to attempt to get clearance but could not get a response from tower as there was continuous communications on the frequency. Other aircraft were cleared to land on 03L and there was a long clearance given to another aircraft. Passing 500 feet we were stable and still on autopilot. I tried to break in on the frequency again but they cleared another aircraft into line up and wait after the 737 (us) landed on 3R. The captain directed me to try again around 100 feet but the frequency was in use. There is certainly a chance in there I stepped on the actual landing clearance. The captain ascertained that we were most likely cleared to land and that to go around at that point with it being night time; terrain at the departure end; and the issues we were having understanding the controllers that the safest course of action was to flare and land. We landed normally and taxied uneventfully to the gate. I understand the captain's thought process and decision; I will say it still surprised me as I was in a go-around mindset at the time.

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Original NASA ASRS Text

Title: B737NG First Officer reported landing without a clearance in MPTO after experiencing communication difficulties with the Tower.

Narrative: I checked in with Tower on the ILS 03R. They said 'Continue 03R'. I had trouble understanding the Controller and said 'Understand cleared to land 3R?' They said 'Negative; continue for 3R'. I acknowledged the 'continue.' There was a lot of communications in two different languages and the English was challenging to understand. Approaching 1000 feet we were fully configured; landing checklist complete. I had not heard a landing clearance; and had not acknowledged a landing clearance. I noticed the preceding aircraft had cleared the runway. During the 1000 foot call we set missed approach altitude and emphasized internally we hadn't thought we'd received a landing clearance. I tried several times to attempt to get clearance but could not get a response from Tower as there was continuous communications on the frequency. Other aircraft were cleared to land on 03L and there was a long clearance given to another aircraft. Passing 500 feet we were stable and still on autopilot. I tried to break in on the frequency again but they cleared another aircraft into line up and wait after the 737 (us) landed on 3R. The Captain directed me to try again around 100 feet but the frequency was in use. There is certainly a chance in there I stepped on the actual landing clearance. The Captain ascertained that we were most likely cleared to land and that to go around at that point with it being night time; terrain at the departure end; and the issues we were having understanding the Controllers that the safest course of action was to flare and land. We landed normally and taxied uneventfully to the gate. I understand the Captain's thought process and decision; I will say it still surprised me as I was in a go-around mindset at the time.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.