RE: Ed Kazmurski's Taurus
Does anyone of you guys know the throw of the old Transmite servos? I'd just like to know the MAN Taurus control throws, and with the linkage geometry in the plan and the Transmite throw I could calculate them.
In the articles, Ed consistently specifies the throws as fractions of one inch, e.g. 5/16" per inch, what makes 18.2 degrees. This way he specifies both aileron (with 20% differential) and elevator (kick-up 34 deg), the latter a bit more down for outside loops. Rudder throw is not specified.
In the simulator, I have now the MAN/TF Taurus and the 1962 Nats (contest) Taurus flying (with a dummy appearence). The airfoil parameters are adjusted (approximated) so that the suspected problem occurs: hard to spin (Ed mentions it). The control throws are: aileron 20 degrees (20% differential), elevator 20 degrees (up and down) and kick-up to 40 degrees (dual-rate), rudder 45 degrees. That's the same for both versions, but the 1" more tail cone length makes much difference (much more than I expected).
The MAN Taurus has the rearward c/g location given in the plan (says 4.75" to 5" behind center leading edge). It needs the slightly rearward c/g both for level-flight trim and for spinning. Despite the elevator throw even bigger than specified and the "terrific" (as Ed calls it) rudder throw, it doesn't spin in the forward c/g position and hardly in the rearward. The Nats Taurus is a bit more stable with the forward c/g position, is still trimmed for level flight, and with the rearward c/g position spins even docile. It's a bit more dampened as well.
I wouldn't sweat the flight characteristics in the simulator too much, they are simply adjusted as descibed by Ed so they can't be completely wrong. After all Ed himself says in the articles that even each model of the same type is slightly different. Now the simulator gives us one important benefit (compared to reality): We can make two models exactly the same and then modify only one parameter (e.g. tail cone length) to assert the differences in flight behavior (e.g. easier spin).