21st Troop Carrier Squadron emblem.  Approved 30 October 1942
<a href="https://en.wikipedia.org/wiki/United_States_Army_Institute_of_Heraldry" class="extiw" title="en:United States Army Institute of Heraldry">en:United States Army Institute of Heraldry</a>
<a rel="nofollow" class="external free" href="https://www.google.com/search?q=21st+troop+carrier+squadron&amp;num=20&amp;rlz=1C1CHWA_enUS627US627&amp;tbm=isch&amp;tbo=u&amp;source=univ&amp;sa=X&amp;ved=0ahUKEwjFm-fekdDZAhVjwYMKHe4mAKgQsAQIRw&amp;biw=1600&amp;bih=747#imgrc=jiyzNVHxDSRgzM">https://www.google.com/search?q=21st+troop+carrier+squadron&amp;num=20&amp;rlz=1C1CHWA_enUS627US627&amp;tbm=isch&amp;tbo=u&amp;source=univ&amp;sa=X&amp;ved=0ahUKEwjFm-fekdDZAhVjwYMKHe4mAKgQsAQIRw&amp;biw=1600&amp;bih=747#imgrc=jiyzNVHxDSRgzM</a>: edited with Microsoft Paint to agree with <cite style="font-style:normal"> (1943). "<a rel="nofollow" class="external text" href="http://archive.nationalgeographic.com/dynamic/National%20Geographic%20Society/National%20Geographic/Landing.aspx">Aircraft Insignia, Spirit of Youth</a>". <i>The National Geographic Magazine</i> <b>Vol. LXXXIII</b> (No. 6): 718-722. National Geographic Society. Retrieved on <span class="mw-formatted-date" title="2017-09-01">September 1, 2017</span>.</cite>