‘Thunderbird’ Mythos — Did US Army Colonel Witness Native American Legend?

In 1948, a retired Army colonel who previously managed an air base, saw what he described as a large bird the size of a “small pursuit plane” above Alton, Illinois. Several civilians backed this up, including two in Northern Illinois the night before, one of whom called it “prehistoric.”

Sources in order of mention

First article: http://i487.photobucket.com/albums/rr232/ufor/news1a.jpg

Second article with section on planes removed: https://virginiachronicle.com/cgi-bin/virginia?a=d&d=SSE19480812.1.7&e=——-en-20–1–txt-txIN-%22monster+bird%22——-

Project Sign/Blue Book “monster bird” file: https://ia601301.us.archive.org/view_archive.php?archive=/8/items/bluebook/1940s.zip&file=1940s%2F1948-04-9670379-4Mi-NOfAlton-Ill-123-.pdf 

Aleuts seeing plane as thunderbird: https://archive.org/details/firstworldflight0000thom/page/n121/mode/2up?q=thunder-bird

Video/image credits

Select B-roll from Alton, IL-area tourism board, all are creative commons reuse allowed: https://www.riversandroutes.com/media/videos-and-b-roll/

Piasa Park (cc) https://youtu.be/o8EucnJW-Jo

Clark Bridge (cc) https://youtu.be/x8KhWckXeYI

Riverview (cc) https://youtu.be/rkMyfQ7ZnPQ

All around (cc) https://youtu.be/B2v96KqUpyU

Alton winter (cc) https://youtu.be/BD7b97RbAdw

All around 2 (cc) https://youtu.be/euqI4mwHLO0

Albatross taking off (cc) https://commons.wikimedia.org/w/index.php?title=File%3AScaling-of-Soaring-Seabirds-and-Implications-for-Flight-Abilities-of-Giant-Pterosaurs-pone.0005400.s005.ogv 

Q. Northropi/Cessna 172 comparison (cc) https://en.wikipedia.org/wiki/Quetzalcoatlus#/media/File:Comparison_of_Quetzalcoatlus_and_Cessna_172.svg

P Sandersi (cc) https://commons.wikimedia.org/wiki/File:Pelagornis_sandersi.png

Quetzalcoatlus (cc) https://commons.wikimedia.org/wiki/File:Life_restoration_of_a_group_of_giant_azhdarchids,_Quetzalcoatlus_northropi,_foraging_on_a_Cretaceous_fern_prairie.png

Artist recreation of Cahokia (cc) https://en.wikipedia.org/wiki/Cahokia#/media/File:Cahokia_Aerial_HRoe_2015.jpg

Thunderbird cave drawing (cc) https://en.wikipedia.org/wiki/Thunderbird_(mythology)#/media/File:ThunderBird_Rock_Carved_Petroglyph_at_Twin_Buffs.jpg

Thunderbird illustration (allowed to use with credit) https://www.deviantart.com/selladorra/art/The-Great-Thunderbird-210219456?comment=1%3A210219456%3A4417403794

Piasa Bird painting (cc) https://commons.wikimedia.org/wiki/File:Piasa_P7090004.JPG