S
- S-PLANE Automation, S-PLANE Automation (Pty) Ltd – South Africa
- Saab AB, Saab AB – Sweden
- Saab, Saab Aircraft AB – Sweden
- Saab, Saab-Scania AB – Sweden
- Saab, Svenska Aeroplan AB Saab – Sweden
- Saab-Fairchild, see SAAB and FAIRCHILD – Sweden/United States
- SAASA, Servicios Aéreas de America SA – Mexico
- Sabrina Aircraft Manufacturing – United States
- SABCA, Société Anonyme Belge de Constructions Aéronautiques – Belgium
- Sadler, Sadler Aircraft Corporation – United States
- SAI (1), Skandinavisk Aero Industri AS – Denmark
- SAI (2), SAI Società Aeronautica Italiana srl – Italy
- Sailplane Corporation of America – United States
- Saint Germain, Centre de Recherches Jean Saint Germain, Inc. – Canada
- Salvay-Stark, M. E. Salvay and George Stark – United States
- Samolot, Poland
- Samsung, Samsung Aerospace Industries Ltd – South Korea, (SSA) > Korea Aerospace Industries
- SAN, Société Aéronautique Normande – France
- Sanderson, Sanderson Machine Corporation – United States
- Sands, Ron Sands Company – United States
- Sargent-Fletcher, Sargent-Fletcher Company – United States
- SATIC, Special Aircraft Transport International Company – France/Germany
- SAU, Nauchno-Proizvodstvennaya Korporatsiya Samoloty-Amfibyi Universalnyye – Russia
- Saunders Aircraft, Saunders Aircraft Corporation – Canada
- Saunders-Roe, Saunders-Roe Limited – United Kingdom
- Sauper, Sauper Aviation SA – France
- Sauser, Sauser Aircraft Company – United States
- Savoia-Marchetti, Savoia-Marchetti – Italy, (1915–1951 & 1953–1983)
- Scaled, Scaled Composites, Inc. – United States
- Scaled Aviation Industries (Private) Limited, Scaled Aviation Industries (Private) Limited – Pakistan
- SCAN, Société des Constructions Aéro-Navales – France
- SCANOR, Société de Construction Aéronautique du Nord – France
- Scenic, Scenic Aviation Services – United States
- Schafer, Schafer Aircraft Modifications, Inc. – United States
- Scheibe, Scheibe Flugzeugbau GmbH – Germany
- Schempp-Hirth, Schempp-Hirth Flugzeugbau GmbH – Germany
- Schempp-Hirth, Schempp-Hirth GmbH – Germany
- Schempp-Hirth, Schempp-Hirth GmbH & Companie KG – Germany
- Schempp-Hirth, Schempp-Hirth OHG – Germany
- Schleicher, Alexander Schleicher GmbH & Co – Germany
- Schleicher, Alexander Schleicher Segelflugzeugbau – Germany
- Schneider, Edmund Schneider – Germany, Australia
- Schweizer, Schweizer Aircraft Corporation – United States
- Scintex, Scintex Aviation SA – France
- Scottish Aviation, Scottish Aviation, Ltd. – United Kingdom, (?-1977) > British Aerospace
- SC Paragliding, Kharkiv, Ukraine
- SCWAL, SCWAL SA – Belgium
- SEA, Société d'Etudes Aéronautiques – France
- Seabird, Seabird Aviation Australia Pty, Ltd. – Australia
- Seabird, Seabird Aviation Jordan LLC – Jordan
- Seastar, SeaStar Aircraft, Inc. – United States
- SET, Societatea pentru exploatari technice – Romania
- Seawind, Seawind, Inc. – United States
- Seat Air Systems, Inc., Seat Air Systems, Inc.,- United States
- Seawind, Seawind International, Inc. – Canada
- Seawind, SNA, Inc. – United States
- SECM, SECM – France, (1916–1921) > Amiot
- Seedwings Europe, Schlitters, Austria
- SEGA Aircraft, SEGA Aircraft – Belgium
- Seginus Inc, Seginus Inc – United States
- Sepecat, Société Européenne de Production de l'Avion ECAT – France/United Kingdom
- Sequoia, Sequoia Aircraft Corporation – United States
- SEREB, SEREB – France, (1959–1970) (Ballistic Missiles Study and Manufacture Company) > Aérospatiale
- Serv-Aero, Serv-Aero Engineering, Inc. – United States
- Servoplant, Servoplant SRL – Romania
- SETCA Société d'Études Techniques et de Constructions Aéronautiques – France
- Seversky, Seversky Aircraft Corporation – United States, > Republic Aviation Company
- SF, Swiss Aircraft and Systems Enterprise Corporation – Switzerland
- SFECMAS, Societe Francaise d'Etudes et de Constructions de Materials – France, (1953–1955) (Société Française d'Etude et de Construction de Matériels Aéronautiques Spéciaux – French Company for the study and construction of special aeronautical materials) > SNCAN
- SFERMA, Société Française d'Entretien et de Reparation de Matériel Aéronautique – France, (Maintenance and Aeronautical Material Repairs Company of France)
- SG Aviation, SG Aviation – Italy
- SGAU, Samarsky Gosudartvennyi Aerokosmitsesky Universitet – Russia
- Shaanxi, Shaanxi Aircraft Company – China
- Shaanxi, Shaanxi Transport Aircraft Factory – China
- Shadin, Shadin LP – United States
- Shanghai, Shanghai Aircraft Manufacturing Factory – China
- Shanghai, Shanghai Aviation Industrial Corporation – China
- Shanghai Sikorsky, Shanghai Sikorsky Aircraft Company, Ltd. – China
- Shenyang, Shenyang Aircraft Corporation – China
- Shenyang, Shenyang Aircraft Factory – China
- Shenyang Sailplane, Shenyang Sailplane and Lightplane Factory – China
- Shenyang Sailplane, Shenyang Sailplane Factory – China
- Sherpa, Sherpa Aircraft Manufacturing Company – United States
- Shijiazhuang, Shijiazhuang Aircraft Manufacturing Corporation – China
- Shijiazhuang, Shijiazhuang Aircraft Plant – China
- Shin Meiwa, Shin Meiwa Industry Company, Ltd. – Japan
- Shin Meiwa, ShinMaywa Industries, Ltd. – Japan
- Shin Meiwa, ShinMaywa Kogyo KK – Japan
- Shinn, Shinn Engineering, Inc. – United States
- Short, Short Brothers & Harland, Ltd. – United Kingdom, (?-1989) > Bombardier Aerospace
- Short, Short Brothers, Ltd. – United Kingdom
- Short, Short Brothers PLC – United Kingdom
- Showa, Showa Aircraft Industry Co., Ltd. – Japan
- Showers-Aero, Milton, Pennsylvania, United States
- SIAI-Marchetti, SIAI-Marchetti SpA – Italy
- SIAT, Siebelwerke-ATG GmbH – Germany
- Siddeley-Deasy, Siddeley-Deasy Motor Car Co., Ltd.. – United Kingdom, > Armstrong Siddeley
- Siebel, Siebel-Flugzeugwerke AG – Germany, (1955–1970) (Siebel Aircraft Factory) > MBB
- Siemens-Schuckert, Siemens-Schuckertwerke – Germany
- Sikorsky, Sikorsky Aircraft Division of United Aircraft Corporation – United States
- Sikorsky, Sikorsky Aircraft Division of United Technologies Corporation – United States
- Silhouette, Silhouette Aircraft, Inc. – United States
- Silvaire, Silvaire Aircraft Company – United States
- Silvercraft, Silvercraft SpA – Italy
- Sindlinger, Fred G. Sindlinger – United States
- Singapore, Singapore Aerospace, Ltd. – Singapore
- Singapore, Singapore Aircraft Industries Pte, Ltd. – Singapore
- Singapore, Singapore Technologies Aerospace, Ltd. – Singapore
- Sino Swearingen Aircraft Corporation – United States/China-Taiwan
- SIPA, Société Industrielle pour l'Aéronautique – France
- Siravia, Siravia SA – France
- Sisler, Sisler Aircraft Company – United States
- SITAR, Sociètè Industrielle de Tolerie pour l'Aéronautique et Matériel Roulant – France
- Sivel, Sivel Srl – Italy
- Skif Paragliding, Feodosia, Ukraine
- Skliar, Bill Skliar – United States
- Skycraft, Skycraft International, Inc. – United States
- Skydancer, SkyDancer Aviation – United States
- Skyfox, Skyfox Aviation, Ltd. – Australia
- Skygear, Korean Light Aircraft Corporation – South Korea
- Skyleader, Jihlava, Czech Republic
- Skymaster Powered Parachutes, Hartland, Wisconsin, United States
- Skyote Aeromarine, Skyote Aeromarine, Ltd. – United States
- Sky Paragliders, Frýdlant nad Ostravicí, Czech Republic
- Skyrider Flugschule – Germany
- Skyrunner Paramotor Laboratory, Pskov, Russia
- Sky Science, Tidworth, United Kingdom
- Skystar, Skystar Aircraft Corporation – United States
- Skywalk GmbH & Co. KG, Marquartstein, Bavaria, Germany
- Skyway Products, Ettenheim, Germany
- Slepcev, Slepcev Aircraft Industries – Australia
- Sling, Sling Aircraft - South Africa
- Slingsby, Slingsby Aviation, Ltd. – United Kingdom
- Slipstream, SlipStream Industries, Inc. – United States
- SMAN, Société Morbihannaise d'Aéro Navigation – France
- SME, SME Aviation Sdn Bhd – Malaysia
- Smith (1), Frank W. Smith – United States
- Smith (2), Wilbur L. Smith – United States
- Smith (3), Barry Smith – United Kingdom
- Smyth, Jerry Smyth – United States
- SNCA, Société Nationale de Constructions Aéronautiques – France
- SNCAC, Société Nationale de Constructions Aéronautiques du Centre – France, (1936–1949) (SNCAC) (Aérocentre) > SNCAN, SNCASO, SNECMA
- SNCAN, Société Nationale de Construction Aéronautique du Nord – France
- SNCAO, Société Nationale des Constructions Aéronautiques de l'Ouest – France
- SNCASO – France
- SNECMA, Société Nationale d'Étude et de Construction de Moteurs d'Aviation – France, (1956–1959) (National Company for the Study and Construction of Aviation Engines)
- Snobird, SnoBird, Inc. – United States
- Snow, Snow Aeronautical Company – United States
- Snow, Snow Aeronautical Corporation – United States
- Soaring Concepts, Sturgis, Michigan, United States
- Société Nouvelle d'Aviation Sportive (Stryke-Air), Noillac, France
- SOCA, Société de l'Ouest de Construction Aéronautique – France
- SOCATA, Socata Group Aerospatiale – France
- SOCATA, Socata Group Aerospatiale Matra – France
- SOCATA, Société de Construction d'Avions de Tourisme et d'Affaires – France
- Soko, Preduzece Soko – Bosnia-Hercegovina
- Soko, Soko Air Mostar – Bosnia-Hercegovina
- Soko, Soko Metalopreradijavacka Industrija sa Organicenom Solidarnom Odgovornoscu Oour-A Oour Fabrika Vazduhoplova – Bosnia-Hercegovina
- Soko, Soko Vazduhoplovna Industrija Radna Organizacija Vazduhoplovstvo – Bosnia-Hercegovina
- Soko, Sour Vazduhoplovna Industrija Soko – Bosnia-Hercegovina
- Soko, Vazduhoplovna Industrija Soko DD – Bosnia-Hercegovina
- Soko-Cniar, see SOKO and CNIAR – Bosnia-Hercegovina/Romania
- Sokopf, Innsbruck, Austria
- Solar Turbines – Solar Aircraft Company – United States
- Solar Wings, United Kingdom
- Solid Air UL-Bau Franz – Hundheim, Rheinland-Pfalz, Germany
- Solo Wings, Gillitts, KwaZulu-Natal, South Africa
- Soloy, Soloy Conversions, Ltd. – United States
- Sol Paragliders, Jaraguá do Sul, Brazil
- Sonex, Sonex, Ltd. – United States
- Sopwith, The Sopwith Aviation Company, Ltd. – United Kingdom
- Sorrell Aviation, C. Hobart Sorrell, Tenino, Washington, United States
- Sorrell, Sorrell Aviation – United States
- SPAD, Société Pour L'Aviation et ses Dérivés – France, (1910–1914) (1914-Post war) (Originally Société Pour les Appareils Deperdussin) > Blériot-SPAD
- Southern Powered Parachutes, Nicholson, Georgia, United States, (formerly called Condor Powered Parachutes)
- Spartan, Spartan Aircraft Company – United States
- Spartan Aircraft Ltd, United Kingdom
- Spartan Microlights, Astoria, New York, United States
- Specter Aircraft, Bancroft, Idaho, United States
- Spectrum Aeronautical – United States
- Spectrum Aircraft – (1983–1992) – Canada
- Speedtwin, Speedtwin Developments, Ltd. – United Kingdom
- Spencer, P. H. Spencer – United States
- Spencer, Spencer Amphibian Aircraft, Inc. – United States
- Sperwill Ltd, Bristol, United Kingdom
- Spezio, Tony and Dorothy Spezio – United States
- Spitfire, Spitfire Helicopter Company, Ltd. – United States
- Spirit, Spirit AeroSystems, Inc. – United States
- Sport 2000, Capena, Italy
- Sport Racer, Sport Racer, Inc. – United States
- Sportavia-Putzer, Sportavia-Pützer GmbH u. Co. KG – Germany
- Spratt, George G. Spratt – United States
- Spring, W. Spring – Canada
- SSH, Serwis Samolotow Historycznich – Poland
- St. Croix, St. Croix Aircraft – United States
- St. Just, St. Just Aviation, Inc. – Canada
- Stampe, Stampe & Renard – Belgium
- Stampe, Stampe & Vertongen – Belgium
- Standard Aircraft Corporation, Standard Aircraft Corporation – United States
- Standard Motors, Standard Motor Company – United Kingdom
- Starck, André Starck – France
- Starfire, Starfire Aviation, Inc. – United States
- Stargate, Inc, McMinnville, Oregon, United States
- Stark, Stark Flugzeugbau KG – Germany
- Stark, Stark Iberica SA – Spain
- Starkraft, Starkraft – United States
- Stark-Trefethen, George Stark and Al Trefethen – United States
- Star-Lite, Star-Lite Aircraft – United States
- Starpac, Star of Phoenix Aircraft – United States
- Statler, William H. Statler – United States
- Staudacher, Staudacher Aircraft, Inc. – United States
- Stavatti, Stavatti Aerospace Ltd – United States
- Stearman, Stearman Aircraft Company – United States, (1927–1939) > Boeing
- Steen, Lamar Steen – United States
- Stemme, Stemme Gmbh & Co KG – Germany
- Stephens, C. L. Stephens – United States
- Stern, René Stern – France
- Stern-Mallick, René Stern et Richard Mallick – France
- Stewart Aircraft Corporation, Stewart Aircraft Corporation – United States
- Donald Stewart, Donald Stewart – United States
- W.F. Stewart Company, Flint, Michigan, United States
- Stinson, Stinson Aircraft Corporation – United States
- Stinson, Stinson Division of Consolidated Vultee Corporation – United States
- Stits, Stits Aircraft – United States
- Stoddard-Hamilton, Stoddard-Hamilton Aircraft, Inc. – United States
- Stolp, Louis A. Stolp – United States
- Storch Aviation, Storch Aviation Australia Pty, Ltd. – Australia
- Storm Aircraft, also called the StormAircraft Group, Sabaudia, Italy
- Stout, Stout Metal Airplane Company – United States
- Stratos Aircraft, Redmond, Oregon, United States
- Streamline Welding, Streamline Welding, Inc. – Canada
- Striplin, Striplin Aircraft Corporation – United States
- Strojnik, Prof. Alex Strojnik – United States
- Stroukoff, Stroukoff Aircraft Corp. – United States
- SUD, Sud-Aviation, Société Nationale de Constructions Aéronautiques – France, (1957–1970) > Aérospatiale
- Sud-Est, Société Nationale de Constructions Aéronautiques du Sud-Est – France, (?-1957) (SNCASE) > Sud-Aviation
- Sud-Est, Sud-Est Aviation – France
- Sudflug, Flugzeug-Union-Süd – Germany
- Sud-Ouest, Ouest-Aviation – France, (1936–1957) (SNCASO) > Sud-Aviation
- Sud-Ouest, Société Nationale de Constructions Aéronautiques du Sud-Ouest – France
- Sukhoi, Gosudarstvennoye Unitarnoye Predpriyatie Aviatsionnyi Voyenno-Promyshlennyi Komplex Sukhoi – Russia, (1939–present)
- Sukhoi, Opytnyi Konstruktorskoye Buro Sukhogo AOOT – Russia
- Sukhoi, Sukhoi OKB – Russia
- Summit, Summit Aviation, Inc. – United States
- Sun Lake, Sun Lake Aircraft – United States
- Sunderland, Sunderland Aircraft – United States
- Sundog Powerchutes Inc, Pierceland, Saskatchewan, Canada
- Sun Flightcraft (Hofbauer GmbH), Innsbruck, Austria
- Supapup, Supapup Aircraft, Division of Teknico Pty, Ltd. – Australia
- Super-Chipmunk, Super-Chipmunk, Inc. – Canada
- Supermarine, Supermarine Aviation Works (Vickers), Ltd. – United Kingdom
- Supermarine, Vickers-Armstrongs (Aircraft), Ltd. (Supermarine Division) – United Kingdom
- Supermarine, Vickers-Armstrongs, Ltd. (Aircraft Section) (Supermarine Division) – United Kingdom
- Supermarine Aircraft, Supermarine Aircraft PL – Australia
- Suresnes – see Ateliers Aéronautiques de Suresnes
- Svenska Aero, Svenska Aero – Sweden
- Swallow, Swallow Airplane Company – United States
- Swearingen, Swearingen Aircraft – United States
- Swearingen, Swearingen Aircraft Corporation – United States
- Swearingen, Swearingen Aircraft, Inc. – United States
- Swearingen, Swearingen Aviation Corporation – United States
- Swearingen, Swearingen Engineering and Technology, Inc. – United States
- Swift Aircraft – Swift Aircraft, Norwich – United Kingdom
- Swing Flugsportgeräte, Landsberied, Germany
- Swing-Europe, Ebringen, Germany
- Symphony Aircraft Industries – Trois-Rivieres, Quebec, Canada
- Synairgie, Synairgie – France
- SZD, Przedsiebiorstwo Doswiadczalno Produkcyjne Szybownictwa-Panstwowe Zaklady Lotnice Bielsko – Poland
- SZD, Szybowcowy Zaklad Doswiadczalny – Poland