Practical and Engineering Problems Mixing or burning these metals with jet fuel in a turbine engine would cause severe issues:

Abrasion and erosion — Hard oxide particles (especially Al₂O₃) would sandblast turbine blades, nozzles, and hot-section components, drastically shortening engine life. Deposits and fouling — Oxides and residues would clog fuel nozzles, injectors, combustor liners, and cooling passages, leading to overheating, reduced efficiency, or failure. Corrosion and chemical damage — Metals can catalyze unwanted reactions, form gums/sludges, or react with water/contaminants to plug filters (known issue even with trace metals). Barium/strontium compounds could exacerbate this. Handling and stability — Powders don't dissolve; they settle, clog lines, require constant agitation, and pose explosion/fire risks. Nanoparticles improve suspension somewhat but still face long-term stability, agglomeration, and regulatory hurdles. Performance penalties — Reduced thrust, higher maintenance, potential flame instability, and non-compliance with certification. Engines are optimized for clean hydrocarbon combustion.