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Aircraft STC directory

McDonnell Douglas DC-9-21 STCs

The Jun 30, 2026 FAA DRS snapshot contains 48 selected supplemental type certificates with status Current whose public applicability data names the McDonnell Douglas DC-9-21. Use it to identify modification scope and recorded holders—not to determine serial-number effectivity, compatibility, installation approval, or commercial availability.

48
listed Current at snapshot
23
holder directories
8
modification categories
Jul 18, 2025
latest recorded revision

Modification demand surface

Other aircraft modifications22
Avionics11
Safety and emergency equipment5
Aircraft structures3
Cabin and interiors2
Cargo and special mission2
Engine and powerplant2
Landing gear and brakes1

Recorded holders

Airborne Maintenance & Engineering Services (AMES)7Amphenol Cable and Interconnect Technologies Inc.6Honeywell International Inc3Avionics Group Inc.3ACSS (Aviation Communication and Surveillance Syst2JanzAir Consulting Services2Rockwell Collins Inc2Safran Cabin Inc.1Acron Aviation Inc.1Purolator Facet, Inc1BF Goodrich Aerospace1Teledyne Controls1Canard Aerospace Corporation1Northwest Airlines Inc1Lufthansa Technik AG1ASTECH Engineered Products Inc.1Repairtech Intl1B/E Aerospace Inc.1USA Jet Airlines Inc.1Goodrich Corporation1

Recently revised DC-9-21 STCs

Showing the 48 most recently revised records. Each entry links to the FAA source and separates public approval data from private commercial claims.