Air carrier flight crew reported a possible collision with a uav on approach to mia.

Narrative:

I was the pm for this flight. We were on a radar vector for the ILS 09 at mia. We were turned to a base to intercept the localizer. The aircraft was at approximately 3000 MSL; configuration 1; gear up. The PF requested that I 'extend a line' for the final approach course. While I was 'heads down' the PF asked 'did you see that?' I heard a muffled thud that seemed to emanate from the bottom of the aircraft. The pm stated that he saw an object that possibly struck the aircraft. He was certain that it was not a bird. The aircraft systems were cross checked and all indications were normal and there were no adverse flight characteristics. ATC was informed of the event and we landed without incident. An entry was made in the aml and maintenance and dispatch were informed of the event. This flight was returning from an international destination therefore we were not permitted to conduct a post flight inspection.this event occurred due to a rapid closure rate of a small inanimate object that may have intentionally or unintentionally been released into class B airspace.

Original NASA ASRS Text

Title: Air carrier flight crew reported a possible collision with a UAV on approach to MIA.

Narrative: I was the PM for this flight. We were on a radar vector for the ILS 09 at MIA. We were turned to a base to intercept the localizer. The aircraft was at approximately 3000 MSL; configuration 1; gear up. The PF requested that I 'extend a line' for the final approach course. While I was 'heads down' the PF asked 'Did you see that?' I heard a muffled thud that seemed to emanate from the bottom of the aircraft. The PM stated that he saw an object that possibly struck the aircraft. He was certain that it was not a bird. The aircraft systems were cross checked and all indications were normal and there were no adverse flight characteristics. ATC was informed of the event and we landed without incident. An entry was made in the AML and maintenance and dispatch were informed of the event. This flight was returning from an international destination therefore we were not permitted to conduct a post flight inspection.This event occurred due to a rapid closure rate of a small inanimate object that may have intentionally or unintentionally been released into Class B airspace.

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.

Attributes
ACN	1466920
Time
Date	201707
Local Time Of Day	1201-1800
Place
Locale Reference	MIA.Airport
State Reference	FL
Environment
Light	Daylight
Aircraft 1
Make Model Name	Large Transport Low Wing 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Flight Plan	IFR
Aircraft 2
Make Model Name	UAV - Unpiloted Aerial Vehicle
Operating Under FAR Part	Other 107
Flight Phase	Cruise
Person 1
Function	Pilot Not Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Inflight Event / Encounter Object