Jeff Spitzer wrote:

larry_cox@ima.connections.com wrote:

What about the heat factor, Tracy ????,  Jeff???,  Paul???

Gas turbine gearboxes are very common on turboprops as we all know.  The
gears must be made to exacting standards to tolerate the high surface
speeds.  Usually AGMA 12 class is a MINIMUM.  These are necessarily ground
gears and cannot be simply hobbed. That is what drives the cost.  The
resulting gear train is extremely efficient even at high speeds with approx
2% per mesh loss.  That's not a lot of heat.

Jeff Spitzer

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