Artist’s rendering shows the Boeing SUGAR Volt advanced commercial transport concept on a tarmac with wings folded. The SUGAR Volt, which would use a hybrid electric propulsion system, is one of several notional concepts for the 2030-2050 timeframe that a Boeing-led team is studying for NASA as part of the Subsonic Ultra-Green Aircraft Research (SUGAR) project. Distinguishing features include battery pods on the wings outside the engines.