I've added reheat to the engines to simulate water injection and then tweaked
it so that it's just about possible to take off with the full fuel load/ferry
configuration (a little under the mtow - 420,000lbs vs 450,000lbs).
It's interesting to note that the normal combat tow for the F model was
291,570lbs - equivilent to a fuel load of about 0.46 (this would actually
leave you with more fuel than in real life because some of that weight would
be the weapons load but here it's fuel)
Anyway, I've added all this info to the readme and explained some of the
reasoning behind the fdm there.
It still doesn't reach the correct altitudes, and certainly not with a full
fuel load, but it starts getting into the right ball park at combat tow.
I've also replaced the transparent instruments on the mini panel with some
text/digital ones. I wanted more accurate numbers when I was monitoring the
effects of fdm changes and the dials just didn't give the detail. They
aren't perfect and be difficult to see against certain backgrounds and in
certain lighting conditions but what the hey - nearly everything I do is a
bit of an experiment;)
Something I've noticed is that since I've started identifying flight surfaces
and gear components individually I've noticed some problems with the flaps
and gear in replay. I address the left and right flaps independently so they
have left&right-flap-pos-norms and don't get controlled by the replay
mechanism which must refer to the single flap-pos-norm. There's a similar
thing with the gear - I have to identify them individually so I can animate
them properly so on the b52 there're six gear elements but only the first
three are actioned in replay.
Personally, I think that the only way around this will be to provide
control-overrides for all these items, much like there're the AP control
overrides for throttle etc.
The base a10 yasim config wasn't working because of the control structure
changes so I've fixed that. The other yasim configs are also included
because I forgot to omit them from the archive but they're not updated or
changed.
All the a10 stuff needs badly re-doing though and it's a bit of a mess - the
yasim configs are all similar but I don't know which ones had Andy Ross's
mods. I've also got to either forget the weapon load version or get it
working with weight entries so that the rest of the configs can be
indentical.
folder. This has meant duplicating most of the instruments it uses but it
should be easier to maintain and once I've worked through all the other a/c
you'll be able to remove a lot of the cruft I'm responsible for in the
generic instrument folders.
The only files that now don't reside in the yf23 folder are the 'set' file and
the yasim config.
The stuff in this archive should replace the entire existing yf23 folder and
the two 'set' and yasim files (unless I've screwed up somewhere;)
There are some small changes to the fdm.
I also had this rather silly idea, so I had to give it a go;) Have a look at
the ground below the a/c.
It doesn't track the Sun, of course, so it stays directly below the a/c. It
just uses a couple of rotations to keep it flat, and a translation to keep it
on the ground. It seemed strange curious that I had to use a translation
factor of 0.3 instead 1.0 to keep it in the right place.
These patches add a clock instrument, which allows to model failure ("serviceable") and to adjust the time independently of the system time (defaults to GMT). The main incentive is to make the p51d clock work and adjustable via the knob.
o Offers a time string ("12:03:15") for the LCD or for LED
clocks, or an empty string in case of failure/power off. The
instrument assumes that digital clocks are battery buffered,
so they will be updated even if there's nothing on the display.
o Offers the number of seconds since midnight for analog
clocks, like in the p51d. This number is not increased
if !serviceable. So the clock will stand still and continue
where it stopped when it's serviceable again.
I did not consider voltage yet, because the Mustang's clock will need a lot more current than the LCD clock. The instrument is updated 4 times per second but returns immediately if neither time nor offset changed. The function getGMTString() in fg_props.cxx could be removed after applying these patches.
I'm not sure if I connected adf and dme to the correct bus, but it's time that c310s have them working. There was a temporary workaround in c310-ifr-set.xml, but not for the c310-3d (= c310u3a-3d), the plain c310 and eventually others.
Here's an update to the yf23. I've added a couple of small details to the
model and played with the textures a bit:) Still no response from the chap
at NASA about sticking their logos on it yet.
I've also been fiddling with the fdm. It had been bugging me that I couldn't
find any sign of air/speed brakes but just recently I found that braking is
done by moving the ailerons up and the flaps down, in opposition to each
other, which I thought was pretty neat really.
This was actually pretty easy to mimic - although there are no spoiler
surfaces defined in the YASim wing entry I was still able to map the spoiler
control input to the ailerons and flaps, and once I'd got the directions
right it seems to work - hit the spoilers and the ailerons move up, the flaps
drop and the energy worm shows that I'm losing speed.
The downside is that the flaps and the ailerons have to have similar lift and
drag characteristics, to balance each each other, and this means that it ends
up with the flaps not giving much lift and the brakes not having much affect
at low speeds. If I could change the deflection rates then I could balance
them that way (and improve the rudder control too) - as it is, the deflection
for the flaps and ailerons is the same, just in opposite directions. This
sounds like a job for interpolation tables but I haven't tried them yet and I
don't know if I can use them in this way in YASim.
The opposing flap/aileron techique is also used for manuevering e.g. by using
it on just one side but I haven't tried to incorporate that yet;)
Landing it is proving to be tricky - it gets down smoothly to about 20ft then
what I presume is ground effect kicks in and upsets the trim. The only
answer appears to be to force the nose down at this point. What's more, it
needs to be held down untill you trim the elevator out otherwise it'll
happily roll along on it's main gear, with it's nose in the air:) There's
definitely not enough drag either.
For the base package I have some more files for the JSBSim airplanes. All of the main configuration files now have a rudder aerosurface scale component, so that rudders can be animated. This was not on my earlier models. I also put fuel in the tanks, even though this seems not to work yet.
Also attached are the -set files for all the airplanes. They now all specify a fuel load.
I've been messing with the yf23 some more. I think it flies a bit better now
and has more reasonable auto-pilot take-off characteristics - just apply full
power and go, and it doesn't go into such a steep climb.
Out of curiosity, I've also taken the rudder control input and linked it to
the stabilators/elevators and ailerons. Now, with some slick joystick
manipulation it's possible to fly it at about 30 deg off-axis in more or less
level flight (actually, with full 'rudder' input, it looks nearer to 40 deg
to me and you end up tracing a very long curve).
If no rudder input is used it flies 'normally'.
I'd like to be able to 'tune' it so that it's more stable while transitioning
but I'm not sure if that's going to be possible. It's also high-lighted some
problems I'm having with my Sidewinder joystick - when I use the rudder
control, the engine No.2 throttle jumps to 50% unless auto-throttle is
engaged (this also happens with the b52 too), and there seems to be some
interaction between the different axis if all three (roll, pitch and rudder)
are changed at the same time - difficult to be sure on that one though.
I'll probably un-map the throttle control from the joystick as I tend to use
the keyboard for engine control anyway, especially for landing.
Here's a quick update to the yf23 fdm and auto-pilot settings. It flies and
takes-off reasonably well - still haven't tried landing it yet;) It can
still be a bit wobbly at times though and It's not very good at terrain
following either.
Taking off on auto-pilot is quite fun. Set full flaps and CTRL-a (assuming
you're near sea level), hit F6 to make it go straight and apply power - about
50% until it rotates then apply full power. Retract the gear as soon as it
gets off the ground and by the time you#ve done that, retract the flaps.
Quite entertaining from a tower view:)
It's not really an ideal a/c to model but apart from the aesthetics, which
appeal to me, I was curious about not having a rudder.
There's a new texture sheet too but it only makes the a/c a paler shade of
grey.
