DeltaHawk Engines, an American company, is currently developing three V-4 designs of 160, 180 and , the latter two versions being turbocharged. Using a ported two-stroke design, they have also flown a prototype engine in a pusher configuration. Velocity aircraft are claiming delivery of non-certified engines since 2005 and hope to achieve certification early in 2011. DeltaHawk engines have a dry oil sump, so they can run in any orientation: upright, inverted or vertical shaft by changing the location of the oil scavenge port. They can also run counter-rotation for installation in twins to eliminate the critical engine issue.