Twin Topics Twin Topics is a monthly column devoted to the operation, maintenance, and ownership of Cessna 300- and 400- series piston twins. It is edited by Mike Busch, CPA’s staff twin expert and the lead instructor in CPA’s twin courses. Mike is a regular contributor to CPA Magazine, as well as editor-in-chief of AVweb, the Internet’s aviation magazine and news service (http://www.avweb.com). He also is the owner of a pristine 1979 Cessna T310R which he maintains almost entirely himself. Vortex Generators: Band-Aids or Magic? A recent visit to Boundary Layer Research revealed that there’s a lot more to those little wing and tail bumps than meets the eye, and that they’re not just for twins anymore! by Mike Busch <
[email protected]> obody’s ever accused seemed like the only one on the engineers would routinely scoff me of being an early- road that didn’t have one! at the VGs on Boeing jets and Nadopter when it comes Even the most died-in-the- brag, “see, we don’t need those to aviation. I’m unabashedly wool skeptics were unanimous things because we got our aero- skeptical about aeronautical in- that vortex generators are a ma- dynamics right in the first novations until they’ve been jor advance in piston twin safety, place.” proven in the field for years. lowering Vmc by ten knots or so The idea of using VGs to When Mobil AV-1 was being to the point that it is no longer a improve the low-speed perform- touted as the greatest thing since factor (because it is below stall ance of general aviation aircraft sliced bread, I stuck with my speed).