Radicaldude1234
Well-Known Member
Hey Guys,
I was just wondering if I could get some pointers in understanding dynamic stability, which is the only thing holding back the design I've been working on. From what I do know about dynamic stability, it is affected by both the aerodynamic shape and the inertial properties of the aircraft, which would preclude me from starting the structural design.
I have a fair understanding of static stability and know some "rules of thumb" for getting good dynamic stability, like having a longer tail for better pitch dampening, more tail volume, etc... I mean, it served me reasonably well in my last design, which had a 12ft wingspan and powered by a 1.5hp engine (RC; designed whilst I was obviously afflicted with Sailplane Design Sickness) Flight Test.wmv - YouTube
Anyways, I have no doubt I can get my rather conventional design (man carrying, this time) to behave reasonably well, but I also want to leave as least as possible to TLAR (That Looks About Right). Performance is something I would rather not discover during flight testing, particularly bad tendencies.
So right now I'm reading through Robert Nelson's Flight Stability and Automatic Control Flight Stability and Automatic Control: Robert Nelson: 9780070462731: Amazon.com: Books. It's an alright text, but not at all very straight forward. I am also reasonably well versed in stability and control concepts, such as Equations of Motion, Stability Derivatives, and Root Locus, though nowhere for something as complex as for an aircraft.
Specifically, I am looking for:
-Determine proper control responses (steady state and ramp-up pitch/roll/yaw rates)
-Whether or not there is satisfactory damping for phugoid, short, and dutch roll modes.
-If I can put all this into an Excel Spreadsheet as a parametric design tool.
-An idea of how analysis of this sort goes.
Thanks in advance guys! And Happy Holidays!
I was just wondering if I could get some pointers in understanding dynamic stability, which is the only thing holding back the design I've been working on. From what I do know about dynamic stability, it is affected by both the aerodynamic shape and the inertial properties of the aircraft, which would preclude me from starting the structural design.
I have a fair understanding of static stability and know some "rules of thumb" for getting good dynamic stability, like having a longer tail for better pitch dampening, more tail volume, etc... I mean, it served me reasonably well in my last design, which had a 12ft wingspan and powered by a 1.5hp engine (RC; designed whilst I was obviously afflicted with Sailplane Design Sickness) Flight Test.wmv - YouTube
Anyways, I have no doubt I can get my rather conventional design (man carrying, this time) to behave reasonably well, but I also want to leave as least as possible to TLAR (That Looks About Right). Performance is something I would rather not discover during flight testing, particularly bad tendencies.
So right now I'm reading through Robert Nelson's Flight Stability and Automatic Control Flight Stability and Automatic Control: Robert Nelson: 9780070462731: Amazon.com: Books. It's an alright text, but not at all very straight forward. I am also reasonably well versed in stability and control concepts, such as Equations of Motion, Stability Derivatives, and Root Locus, though nowhere for something as complex as for an aircraft.
Specifically, I am looking for:
-Determine proper control responses (steady state and ramp-up pitch/roll/yaw rates)
-Whether or not there is satisfactory damping for phugoid, short, and dutch roll modes.
-If I can put all this into an Excel Spreadsheet as a parametric design tool.
-An idea of how analysis of this sort goes.
Thanks in advance guys! And Happy Holidays!
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