Robert Sanderson takes Hurries to the desert
Moderators: Guru's, The Ministry
Robert Sanderson takes Hurries to the desert
Up at Avsim...
This is another excellent model in Robert S's Hurricane series.
If I may point out one slight error: in the 'aircraft,cfg' file, the [airplane_geometry] section defines the wing area as '320.0'. The true Hurricane wing area (in the superb notes provided with the model, as well as in the 'aircraft' files for the other RS Hurricanes) is 257 sq ft.
Why does this matter, I hear you ask?
Well, if you take the model to above 250 kt, you will notice a lot of uncommanded, unrealistic pitching going on. Try changing the wing area to '257.0' and it all goes away.
I offer this as a fix, but I haven't had time to check everything out yet: it doesn't seem to have any adverse effect.
Cheers,
Kevin
If I may point out one slight error: in the 'aircraft,cfg' file, the [airplane_geometry] section defines the wing area as '320.0'. The true Hurricane wing area (in the superb notes provided with the model, as well as in the 'aircraft' files for the other RS Hurricanes) is 257 sq ft.
Why does this matter, I hear you ask?
Well, if you take the model to above 250 kt, you will notice a lot of uncommanded, unrealistic pitching going on. Try changing the wing area to '257.0' and it all goes away.
I offer this as a fix, but I haven't had time to check everything out yet: it doesn't seem to have any adverse effect.
Cheers,
Kevin
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DaveB
- The Ministry
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Kevin..
This sort of thing is often done to overcome other deficiencies with the models flight envelope and can be disasterous if fiddled with. However, if you're happy with the result.. then okey doh
Have a look at the wing area for the JP5 when you have a minute and I would definately not advise you try altering that to 'known' figures
ATB
DaveB :tab:
This sort of thing is often done to overcome other deficiencies with the models flight envelope and can be disasterous if fiddled with. However, if you're happy with the result.. then okey doh
Have a look at the wing area for the JP5 when you have a minute and I would definately not advise you try altering that to 'known' figures
ATB
DaveB :tab:
Old sailors never die.. they just smell that way!
Dave,
Yes, I'm well aware that the FDEs in flightsim are much less an accurate representation and much more an exercise in low cunning!
. I've done a few myself.
However, my point is that there is a significant error in the handling of this aircraft which isn't present in Robert Sanderson's previous Hurricanes; it manifests itself as a continuous nodding in pitch, without any elevator deflection (commanded or otherwise), at speeds above 250 kt or so. This is wrong.
From previous experience, I know that this authors FDEs are usually immaculate, so rather than dive into it in the way I would attack an Ito model, I looked for a possible single error.
Looking at the FDEs for the previous RS Hurricanes, and comparing them with the Mk IID (which aren't very different), I tried several ways to improve the handling by using elements of his earlier files and eventually found that the only element which completely eliminated the error was to revert to the 'earlier-used-by-RS' value for the wing area. It happens by chance to be the correct wing area for the Hurricane, but that's beside the point.
I do understand your point about 'fiddling with' the flight model, but I hope that with my 30 years experience as an aerodynamicist/aeronautical engineer and 25 years as a pilot, together with a few years of flight sim, I'm a bit beyond that
I agree that other elements of the flight envelope might be affected, as I mentioned in my first post, but I haven't found any yet.
Cheers,
Kevin
Yes, I'm well aware that the FDEs in flightsim are much less an accurate representation and much more an exercise in low cunning!
. I've done a few myself.However, my point is that there is a significant error in the handling of this aircraft which isn't present in Robert Sanderson's previous Hurricanes; it manifests itself as a continuous nodding in pitch, without any elevator deflection (commanded or otherwise), at speeds above 250 kt or so. This is wrong.
From previous experience, I know that this authors FDEs are usually immaculate, so rather than dive into it in the way I would attack an Ito model, I looked for a possible single error.
Looking at the FDEs for the previous RS Hurricanes, and comparing them with the Mk IID (which aren't very different), I tried several ways to improve the handling by using elements of his earlier files and eventually found that the only element which completely eliminated the error was to revert to the 'earlier-used-by-RS' value for the wing area. It happens by chance to be the correct wing area for the Hurricane, but that's beside the point.
I do understand your point about 'fiddling with' the flight model, but I hope that with my 30 years experience as an aerodynamicist/aeronautical engineer and 25 years as a pilot, together with a few years of flight sim, I'm a bit beyond that
I agree that other elements of the flight envelope might be affected, as I mentioned in my first post, but I haven't found any yet.
Cheers,
Kevin
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DaveB
- The Ministry
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Rgr that Kevin
I wonder why he did that with this particular model then :think: I've not given it a run yet but I totally agree that a nodding pitch is best got rid of and sharpish. I remember downloading a lovely B52 many moons ago that did this in the cruise. Shame there were no chaps like you around at the time to sort it out!!
ATB
DaveB :tab:
I wonder why he did that with this particular model then :think: I've not given it a run yet but I totally agree that a nodding pitch is best got rid of and sharpish. I remember downloading a lovely B52 many moons ago that did this in the cruise. Shame there were no chaps like you around at the time to sort it out!!
ATB
DaveB :tab:
Old sailors never die.. they just smell that way!
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Vulcan_to_the_Sky!
- Concorde
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Dave,
Thanks
I was wondering that, too. I did notice that his notes acknowledged a collaboration - therefore files going back & forth - maybe the file that was issued wasn't the one that was meant to go out? It's very easy to miss something like this in the 'issue version', which might not be the one you think it is.
I have e-mailed Robert Sanderson with the suggested mod - let's see what he says.
Cheers,
Kevin
Thanks
I was wondering that, too. I did notice that his notes acknowledged a collaboration - therefore files going back & forth - maybe the file that was issued wasn't the one that was meant to go out? It's very easy to miss something like this in the 'issue version', which might not be the one you think it is.
I have e-mailed Robert Sanderson with the suggested mod - let's see what he says.
Cheers,
Kevin