Helmetless Power Rangers

MMPR season 1 0 No No helmetless scenes.
MMPR season 2 102 No Page includes "Alpha's Magical Christmas" and MMPR: The Movie (not included in counts here).
MMPR season 3 / MMAR 53 No  
Zeo 99 No  
Turbo 28 Some  
In Space 22 No  
Lost Galaxy 15 Most  
Lightspeed Rescue 17 No Open visors are counted separately.
Time Force 0 No No helmetless scenes.
Wild Force 0 Yes No helmetless scenes (outside of morph sequences).
Ninja Storm 3 Yes Open helmets are counted separately.
Dino Thunder 9 Yes  
SPD 5 Yes  
Mystic Force 5 Most  
Operation Overdrive 10 Yes Count includes retro Ranger team in "Once a Ranger."
Jungle Fury 1 Sort of  
RPM 26 Yes  
Samurai 1+ Sort of  

Note: Teams without helmetless scenes in-show (i.e. Time Force) may still have been photographed helmetless for promotional materials. These materials are not counted above.