Which specific MH370 debris items carry unique part numbers that proved they came from 9M‑MRO?
Executive summary
Two recovered pieces of floating debris carry the clearest unique identifiers tying them to the Malaysia Airlines Boeing 777 registered 9M‑MRO: the Réunion Island flaperon, which bore stencils and one of three numbers that matched the aircraft's serial, and an outboard wing flap (often referred to as "part number 5" or the Pemba/Tanzania flap) whose stamped part numbers and date code are consistent with 9M‑MRO’s delivery records [1] [2] [3] [4]. Other finds have strong forensic or contextual evidence linking them to MH370 but lack unique part numbers that would definitively prove they came from 9M‑MRO [5] [6] [7].
1. The flaperon: a stencil, a code and one number matching 9M‑MRO
The first and most publicised identifier came from the flaperon recovered on Réunion Island in July 2015, which carried multiple stencilled marks including a code (widely reported as 676EB) and—critically—one of three numbers on the part that French judicial investigators matched to the missing aircraft’s serial and maintenance records for 9M‑MRO, a finding reiterated by BBC and other reporting [1] [2]. Investigators also noted the stencil style and "No Step" markings matched Malaysia Airlines’ application and that paint and fastener details aligned with the aircraft’s maintenance history, strengthening the unique linkage beyond simple similarity of shape [1] [2].
2. The outboard flap (part number 5 / Pemba flap): stamped parts and a date that fit 9M‑MRO
A second, widely reported confirmation came from a flap segment found on Pemba Island (Tanzania) and other east‑African finds which were examined and designated in formal reports—one being described as "part number 5"—where investigators read part numbers and a manufacture/date stamp (manufactured 23 January 2002) that matched the delivery timeframe and line number for the aircraft later registered 9M‑MRO, making the identification a specific trace to that airframe rather than a generic 777 part [4] [3] [8]. Australian and Malaysian authorities treated this evidence as a strong identifier because the stamped information corresponded to aircraft production and registration records [4].
3. Items that are almost certain but lack unique part numbers
Numerous other debris items have been characterised as "almost certainly" or "very likely" from 9M‑MRO on the basis of material, laminate patterns, fastener types, paint, stencil style, and drift modelling, but they do not carry unique part numbers that incontrovertibly tie them to that specific airframe [6] [7] [9]. Official statements exemplify this distinction: for some panel segments authorities explicitly reported that there were no identifiers unique to 9M‑MRO even though the laminate and finish matched Malaysia Airlines' specifications [5]. The ATSB and BEA used a combination of forensic matching and provenance modelling for such items rather than single unique part numbers [6] [7].
4. What "proved" means in this investigation and remaining limits
In the context of MH370 debris work, "proved" has two tiers: definitive proof via unique stamped or serial numbers traced to the aircraft’s manufacturing or records (as with the flaperon and the flap/part‑5 item), and strong probabilistic attribution based on construction, serial manufacturing practices and drift science (as with many other finds) [1] [4] [7] [5]. Public reporting and the formal safety investigation make clear that only a subset of recovered pieces carried the kind of unique identifiers that can be matched directly to 9M‑MRO; many others remain high‑confidence attributions but without that singular forensic tag [5] [6].