McDonnell Douglas DC-9-50
17,327 parts applicable to this airframe — narrowbody
Top Replacement-Prone Parts(8)
From FAA SDR — directional buying signal, not a failure rate
| Part # | Propensity | SDRs |
|---|---|---|
| 591014167 | 100%* | 37 |
| 59516395001 | 100% | 24 |
| 59101415 | 100%* | 23 |
| 37723745503 | 100% | 20 |
| 41B001TD05G1 | 100% | 13 |
| 59568791 | 100%* | 13 |
| 59122851 | 100%* | 11 |
| 5919526508 | 73% | 11 |
* Structural ATA chapters use FAA K-code change rate. Verb-based propensity is suppressed there because "REPAIRED" in the SDR text usually refers to the airframe being repaired around the part.
Utilization & cargo trend(US carriers, 2015–2025)
MD-80 family rollup — BTS T-100, domestic + international
US carriers only (BTS T-100, domestic + international segments) — foreign-carrier flying is excluded, so global utilization runs higher. Fleet size is reconstructed from the FAA registry (built on or before each year, not yet deregistered) — an approximation. Freighter share counts departures with zero passengers and freight aboard — a proxy for freighter/combi operations, not a tail-by-tail conversion count. Missing years render as gaps.
USM supply — retirements & teardowns(2023–2026)
MD-80 family — FAA registry deregistrations
FAA registry data. Domestic deregistration is a teardown proxy — it also captures re-registrations and some unflagged exports, so it is not a confirmed part-out count; exported aircraft left the US fleet intact and are not USM supply. ATA shares reflect where this directory's parts for the family concentrate (parts in parentheses) — a coverage signal, not the aircraft's bill of materials or a teardown-yield forecast.
Engine-program supply pressure(since 2023)
FAA registry — US-registered fleet
Engines account for roughly half of all MRO spend, so engine programs shedding aircraft are where retirement supply carries the most value.
| Engine model | Active tails | Engine units | Retired since ’23 | Exported | Avg age at dereg |
|---|---|---|---|---|---|
| P & W JT8D series | 84 | 172 | 29 | 8 | 34.4 yr |
| P & W JT8D-219 | 22 | 44 | 4 | 0 | 34.5 yr |
| P & W JT8D-9 series | 9 | 24 | 4 | 2 | 53.8 yr |
| P & W JT9D series | 13 | 37 | 3 | 0 | 41.7 yr |
| P & W JT8D-1 | 8 | 21 | 3 | 0 | 33 yr |
| P & W JT8D-17 series | 7 | 16 | 1 | 1 | 44 yr |
| P & W JT8D-15 | 6 | 13 | 1 | 1 | 51 yr |
| P & W JT8D-9A | 5 | 11 | 0 | 0 | — |
FAA registry data, US-registered aircraft only. Counts reflect the engine model as registered — generic “series” rows coexist with thrust-variant rows, so per-variant figures are partial. Retired = domestic deregistrations (a teardown proxy, not a confirmed part-out); exported aircraft left the US fleet intact. Active tails span every family the engine flies on, not just this one.
Maintenance economics(US carriers, through 2026)
MD-80 family — BTS Form 41 filings
BTS Form 41 data (Schedule P-5.2 maintenance expense over T-2 block hours), Group III US carriers only — filers above $1B annual revenue; smaller US operators, Part 135, and all non-US carriers are not in this data. Dollars are accrual-basis from regulatory filings (reserves and depreciation included), so they benchmark fleet economics and do not track to individual repair events. Averages are block-hour- weighted across every reporting carrier; the range spans per-carrier rates after excluding marginal reporting slices, and small carrier counts are noisy.