Because I"m a bit out of the loop, has anyone built a bearing section to bolt to the end of the crankcase to take flight loads? is that what the "5th bearing" is? and has anyone tried to design one that completely removes everything but torque loading from the crankshaft?
On Wed, May 22, 2013 at 9:49 AM, Mark Langford <ml at n56ml.com> wrote: > I wrote something yesterday about more powerful engines being "safer" than > lower powered ones in a given plane. This was from a "gain altitude as > quickly as possible on takeoff" standpoint. I'm a little surprised that > nobody called me out on using the Corvair as an example, given that I've > broken three Corvair crankshafts, the last one on takeoff. There is no > denying that the Corvair has crankshaft issues, at least in my mind. In > contrast, the VW-based engines such as the Great Plain Aircraft 2180 have > essentially mitigated that problem by use of high quality 4340 crankshafts > and the Force One hub. VWs tend to fail more slowly, with valve or > crankcase issues, whereas the Corvair has had more than its share of > instantaneous crankshaft failures of the variety that will ruin your day, > at > least in my experience. There is now limited production of 4340 > crankshafts > for the Corvair, but they are pricey, and there's only one flying so far. > I > do have one on order. > > > > I'm not bringing this up for any other reason than to be fair to the VW. > They are reasonably reliable engines and there are a lot in service in the > small homebuilt world. Steve Bennett told me a few months ago, that none > of > his engines have broken a crank that has been running his Force One hub, > and > that's a lot of years and a lot of engines! > > > > Mark Langford > > ML at N56ML.com > > see experimental N56ML at www.N56ML.com > > > > > > _______________________________________________ > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org > please see other KRnet info at http://www.krnet.org/info.html > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options >
