Spuckbeutel Air Sickness bags
  Airlines Sm - Sz
 
SMAC - Sabang Merauke Raya Air Charter, Medan, Sumatra, Indonesia, founded 1969:

Small Planet Airlines, Vilnius, Lithuania, founded 2010.  Also registered in Poland in 2010.   - #1:

SN Brussels, Belgium,2002- 2006,  successor of Sabena (q.v.  Brussels Airlines):

Sobelair, Brussels, Belgium, 1946-2004.      -   #1    and   #2:

SOL Lineas Aereas, Rosario, Argentina, founded 2006.  - #2:

SOL Linhas Aereas, Cascavel, Brazil, founded 2008.  -#1:

Solaseed Air, Miyazaki, Japan, founded 2011 by rebranding from
SNA Skynet Asia (q.v.). - with thanks to Toshiaki Anan - #1:

Solid Air, Eindhoven, Netherlands, 1996-2011.    #1:

Solomon Airlines, Honiara, Solomon Islands, founded 1968 by renaming from Megapode Airlines.  #2:

SonAir, Luanda, Angola, founded 1998.     -   #2:

SONG LLC, Atlanta, Georgia, USA, 2003-2006. Song was a low fare brand of Delta(q.v.).
-with thanks to Dr. David Bradford -    #1:

South African Airways, Kempton Park, founded 1934. 
#6,                        #4/#9(diff height stripes area),         # 2           and              #3:

#12(flat base)/#19(pointed base),       #5a/ #7(diff paper),       #1       and          #10:

Southern Winds Airlines, Córdoba, Argentina, 1996 - 2005.    -  #1,       #5:

Southwest Airlines, Dallas, Texas, USA, founded 1971:
 
SPANAIR, Barcelona, Spain,  1986 - 2012.
-     #4/#9(diff paper),               #6,                     #1                  and                    #7:

#8,                         and             #12:

SPANTAX, Madrid, Spain, 1959 - 1988.   #1:

SPICEJET, New Delhi, India, founded 2005.
- with thanks to Gerd Clemens - #2,             #6,        #7/#8      and                     #9:

Spirit Airlines, Miramar, Florida, founded 1980.    - #2:

SPRING Airlines, Shanghai, China, founded 2004.
#2,                                       #3,                                       #4,                                     #5:

Sri Lankan, found 1979 as Air Lanka (q.v.) and renamed 1999.  
         - #3,               #1/#2(with resp w/o Tear off strip),               #4:

Sriwijaya Air, Jakarta, Indonesia, founded 2003.   -   #3,      #1,      #6,       and    #7:

Star Air of Indonesia, founded ?, ceased 2005:

Star Airlines, Paris, France, 1997 - 2006. Renamed to XL Airways France(q.v.).
-              #2,                                             #3:

StarFlyer, Kitakyushu, Fukuoka, Japan, founded 2002.
  #2(flat base),         #3(sealed base)             and   - with thanks to Tom Hiett -  #4:

Star Peru, Lima, founded 1995.         #3       and  - with thanks to Annika Slavetic- #4:

Sterling, Copenhagen, Denmark, 1962-1993.    #5(matt)/#5A(glossy),     #3       and #6:
 
       #1,                                  #2,                                        #4                and  #8:

SEA Sterling European Airlines,  Copenhagen, Denmark, 1994-2008.
- with thanks to Thorsten Hecht -  #1:

Stuttgarter Flugdienst (SFD Aviation), Stuttgart, Germany, founded 1956.   -   #1:

Sudan Airways, Khartoum, founded 1947.   -   #2    and    #8:

Sun Country Airlines, Minneapolis, Minnesota, USA, founded 1982,
- with thanks to Dr. David Bradford -      #1            and       #6:
 
Sun Express, Antalya, Turkey, founded 1989.
- #1,         #2,     #3/#3a(glossy/normal paper)/ #4/#5(normal/glossy)/#6(glossy) diff. makers in gussets.

Sunu Air, Dakar, Senegal, founded 2003.   - with thanks to Bruce Kelly - #1:

Sunwing Airlines, Toronto, Canada, founded 2005.   -     #1,            #3:

Super Constellation Flyers, Basel, Switzerland.   - with thanks to Frank Mulliri :    #1

Surinam Airways, Paramaribo, Suriname, founded 1955.  # 4,   #5  and - with thanks to Ed Sluimer - #2:

Swedair, Stockholm, Sweden, 1975-1994.  -  #3:

Swissair, Zurich-Kloten, 1931-2002.   -  #17(old, 30cm tall bag)front and rear shown:
    
#4/#16(diff paper),              #6      and       #12/#14/#15(diff cut, base, tear off strip):

#3/#5(diff paper),                       #10/#9(Name at base upright low),           #11:

Swiss International, Basel, Switzerland, founded 2002.
#3,                         #4,                          #8                      and                 #5 / #6: