Experimental Torsion Hybrid Onager System

We are a pumpkin chunkin’ catapult team founded in 2006 in Dayton Ohio. Most of our team members work for or are associated with Wright Patterson Air Force Base.

Our machine, “The Phoenix”, is based on the ancient Greek concept of torsion. It derives its throwing power from a bundle of twisted ropes. The Greeks, and later the Romans, had several types of catapults based on this concept, one of which was known as an Onager.

Our mission is to research and design a world-class onager using modern materials, modern experimental methods, and advanced analysis techniques. We are continuously experimenting with different concepts to improve performance, and we thrive on the pursuit of understanding the physics of these complex machines.

Events for 2018

Team ETHOS participates in demonstrations, contests, and educational activities.  If you are interested in engaging us for a demonstration of educational event, please contact us!

Contest Results

Below is a summary of our contest ranges and placings.  For more details of the current year contest shenanigans, see the Chunk-umentory page.  “WPAFB" = Wright Patterson AFB, “World” = World Championships, “PCCO” = PC Colorado


WPAFB: 1st, 3288 feet
PCCO: 1st, 3776 feet


WPAFB: 1st, 3176 feet
World:  1st, cancelled


WPAFB: 1st, 3391 feet
World: 1st, 3202 feet


WPAFB: 1st, 3224 feet
World: cancelled


WPAFB: 1st, 3458 feet
World:  cancelled


WPAFB: cancelled
World:  2nd, 2424 feet


WPAFB: 1st, 1908 feet
World: 4th, 2237 feet


WPAFB: 1st, 2972 feet
World: 3rd, 2911 feet


WPAFB: 1st, 1220 feet
World: 6th, pie only


WPAFB: 1st, 1461 feet
World: 1st, 2088 feet


WPAFB:  n/a 
World:  4th, 1190 feet


WPAFB: 2nd, 635 feet 
World: n/a


A Catapult can cause injury, death and/or damage to property, either through construction, operation, misuse, component failure, errant (or deliberate) aiming, impact of payload, etc. The ETHOS Catapult Endowment and Team ETHOS assumes NO responsibility for any use of the material contained in this website.  Anyone who uses information obtained from or through this web site, for whatever purposes, is solely responsible for its use and the consequences thereof. Neither ETHOS Catapult Endowment and Team ETHOS nor any of its affiliates, shall be held liable for the information contained herein.

Built by Catapult Cowboy