Cheli holds a commission as a Lieutenant Colonel in the Italian Air Force.
Most recently, Cheli was a mission specialist on the crew of STS-75. The principal payloads on STS-75 were the reflight of Tethered Satellite System (TSS) and the third flight of the United States Microgravity Payload (USMP-3). The TSS successfully demonstrated the ability of tethers to produce electricity. The TSS experiment produced a wealth of new information on the electrodynamics of tethers and plasma physics before the tether broke at 19.7 km, just shy of the 20.7 km goal. The crew also worked around the clock performing combustion experiments and research related to USMP-3 microgravity investigations used to improve production of medicines, metal alloys, and semiconductors. STS-75 launched February 22, 1996 and landed back at the Kennedy Space Center on March 9, 1996. The mission was completed in 252 orbits covering 6.5 million miles in 377 hours and 40 minutes.
Carried TSS-1R tether satellite; satellite tether broke during deployment, making TSS-1R an unintentional free flyer
Payloads: Tethered Satellite System (TSS) Reflight (1R); Orbital Acceleration Research Experiment (OARE) (part of United States Microgravity Payload 3); USMP-3; Commercial Protein Crystal Growth (CPCG) 09, Block IV; Middeck Glovebox Experiment (MGBX) (part of USMP-3). During the deployment of TSS, the tether broke and the satellite was lost.