Specifications include, but are not limited to: Vendor shall provide quality aviation petroleum lubricants, quality aviation repair parts, and qualified aviation mechanics to perform routine aircraft maintenance for the ISP fixed wing aircraft at Springfield’s Abraham Lincoln Capital Airport to ensure aircraft are in a safe and airworthy condition. The ISP reserves the right to inspect and evaluate the parts and services provided for quality and to ensure parts at being purchased at a competitive price. Maintenance shall include, but not be limited to, the following: 50-hour Interval: Oil change with AvBlend additive; change filter/clean oil screen; take oil sample for send-in for analysis; check, clean, and gap spark plugs; compression check; clean underside of aircraft; repair noted discrepancies. 400-hour Interval: Perform a 100-hour inspection; oil change with AvBlend additive; change filter/clean oil screen; check, clean, and gap spark plugs; compression check; clean underside of aircraft; repair notes discrepancies; Lycoming engines: Valve inspection per Lycoming service bulletin 388C (not variable-always 400 hours).