anyone notice how much more lift the mig29 has. It seems to climb in level flight and I musdt point the nose down periodically. pretty cleaner turner the G is
it there any drag/weight penalties that come in when equipping the UV-5-08 countermeasure blocks? Not modelled? They are chunky
Yes, that’s how it should be, you have to point your nose down to keep the horizon.It will be the same on the Su-27
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what does drag/weight mean?
Yes, it’s called positive speed stability. Also in Mig-29, thrust is applied below CoG causing very pronounced pitch-up effect especially at low IAS and low altitudes. (Description from https://www.digitalcombatsimulator.com/upload/iblock/dcc/DCS%20FM%20principles%20plus%20MiG-29%20P-47%20F-16.pdf)
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Strangely, the curve actually shows negative speed stability below 0.85 mach. Positive stabilizer angle means trailing edge down, or stick forward. Here’s the one for Su-27:
The Su-27 is a statically unstable stable aircraft.He is constantly being pulled up.Up to supersonic speeds
Yes, statically unstable but speed stable (pitching up with increasing speed) as shown in the graph.
Su-27 has a trim schedule in the control law of pitch FBW (SDU-10) to further provide speed stability with increasing speed:
this is not a graphic block diagram
almost all the signatures here are not correct
It actually has all the transfer functions and gain schedules you need to replicate the control response in Matlab simulink, or code in C++.
What’s incorrect then, it’s from the SDU-10 manual.
Trim shedule,lag filter
without knowing the equations, these are all useless graphs
What they should be called? The former is an open loop schedule added to the original input, while the latter essentially forms a first-order lag filter (1/tS+1)with filter rate limit.
Well, those are not equations. Those are gain schedules and transfer functions, if you know control theory or know how to build a graph in Simulink.
I’ll get a book on the control system when I get home
I have a cleaner version of those schedule. It’s pretty straight forward:
For the trim schedule, enter the graph with dynamic pressure q (kg/m^2), and get the stick throw (mm), which is then added to the stick input. This affects trimming of the aircraft and increases speed stability.
For the lag filter, take the input and multiply it by 5, limit it by the rate limit (20 grad/s), and multiply it by the gain schedule K(q). Remember q is dynamic pressure? This is to reduce control sensitivity (hence lag) at higher speed. And then it goes through an integrator to form the output. The output is then subtracted from the input, forming a closed loop, thus the lag filter.
BTW the block diagram of F-16 is a ton more complex: F-16数字电传操纵系统DFLCS控制律功能模块拆分和说明（2024修订） - 哔哩哔哩 (Use a translator.)
- ◊MiG-29, MiG-29, MiG-29SMT : Added VWS Overrides
What does that mean?