B-S Model 75 - the visual model

[aleatorylamp]

Hello Smilo,
Not to be sorry by any means!
It bothers me too. I can´t find the way to trim the airplane to stop this annoying
and persistent left bank/yaw tendency. There should be a way, shouldn´t there?

Obviously engine torque is the culprit, because it stops when throttling back to idle.

I´ve tried adjusting aileron and rudder trim to zero, dividing it by 2, multiplying it by
10, changing plus to minus and minus to plus, but it doesn´t change a thing!

Neither does it seem to be affected by the Propeller Sluggishness parameter, with which
I thought it might be combined.

So, for the moment, we have to leave it as it is.

I increased pitch moments due to elevator and rudder a little, and reduced prop effect on
rudder, to see if control is a bit better, but it´s all a bit much of a muchness, really.

Anyway, we´ll see!
Cheers,
Aleatorylamp

[smilo]

am having an old man moment here.
as i recall, the trim conversation
has been had before.
i just can't remember where and
if a solution was ever reached.

after flying a bit yesterday,
i was able to adjust the trim
enough to attain satisfactory results.
needless to say, it takes patience
and constant vigilance to maintain
straight and level flight, but,
it can be done.
she's a trainer, after all.

needless to say, i haven't had a chance
to test the wep.
i am a bit curious about the results
of letting it run out
and the damage to be caused.
i can't help but wonder,
how the pilot will know
when he is close to catastrophe?
there is no wep indicator.
is he suppose to run a stop watch,
or is it just guess and by golly?
granted, i have a wep timer in my hud,
but, it is a digital counter.
i doubt such a thing was available
back in 1930s and 40s.

ps...i have lost the ap.
it didn't seem appropriate.

[aleatorylamp]

Hello Smilo,
Well, OK. It appears that the real plane had some torque effect issues too, which could be trimmed out to some extent, but not completely.

Regarding the use of WEP for 105% power:
In the .air file, the Maximum Manifold Pressure stays at the default 30 inches of mercury, and Boost Gain is set to 0.51, not Zero, and WEP type is defined (not zero).

This combination allows the smallest possible CFS1 power increase , which seems to be 5.5 %.
Looking at a boost gauge, a small Manifold Pressure change of about 1 inch of mercury at operating altitudes can be seen. Such a change would in any case be coherent with moving the throttle lever to full max.

Interestingly enough, lower entries for Max. Manifold Pressure and Boost Gain will yield ZERO extra power.

The problem with WEP, as you said too, is that it is impossible to predict when it times out.

That´s why I had the alternative idea to have the full 105% power available all the time, and a coloured scale marked on the Throttle bitmap, and a line on the throttle handle, tells you if you are in the "red" zone. Of course, no damage will be done if you stay there!

This way, compared to the real aircraft, the engine would have a permanent instead of a limited-time capacity for 105% performance. This also happens in CFS with the use of 100% full throttle, which should only be used for 5 minutes in reality.

Thus, there is a third alternative: No extr 5% power.
Do what most flying schools must have done, simply to block the throttle lever travel so it doesn´t give the extra 12 Hp.

As I am not much of a simmer and rather a builder, I don´t know what is best, so I keep asking the question.

At the moment, WEP Type 2 (Methanol-Alcohol injection) is implemented. I.e., after about 5 minutes, WEP is ruined, but the engine remains intact, keeping its rated 220 Hp at S.L.

Alternatively, implementing Type 3 WEP (WEP type supercharger), it cripples the engine to 50% power.

So we really have a wide choice:
1) No 105% power - keep it at 220 Hp.
2) 105% power to be used at the user´s discretion - no damage incurred.
3) 105% power available until it times out, losing the 5% power.
4) 105% power available until it times out, crippling the engine with a 50% loss of power.

So...
Cheers,
Aleatorylamp

[smilo]

...which in turn leads to a favorite cliché;
so many choices,
so little time.

i finally got around to testing the wep
and was a little disappointed
when the engine didn't crap out.
so it goes.
back to the choices.

i'm leaning toward the kiss option #1,
keep it simple stupid.
do i need to give my reasons?

as for the engine torque pull to the left,
(is it the P-Factor?)
for as long as i can remember,
i have desperately tried to taxi
in a straight line during takeoff.
of course, in the old days,
i would just firewall the throttle
and hope i could get into the air
before i'd run into something.
now, it's gently throttle up,
while giving a few kicks of right rudder.
careful, though, not too much,
or you'll over compensate.

[aleatorylamp]

Hello Smilo,
OK, thanks for the opinion! Yes, the more one thinks about it, the less worthwhile it seems to complicate issues for so little extra power anyway. Let´s do without it. It´s easy to take out by just de-activating WEP and Supercharger.

However, should you want to see how its overuse ruins the engine, just for fun, all you have to do is enter the value "3" into "Emergency Power Type" in Record #505 (Engine CFS/FS2000 Piston Engine), which at present has the value of "2". After about 5 minutes your engine turns into a clanking wreck!

As regards the leftward yaw, maybe in the old days on their grass strips, they could hardly tell if they were taxiing in a straight line anyway...

During take-off the effect is stronger than during normal flight, apparently because of the stronger propwash against the rudder. Then, with high angles of attack, it gets even worse when the "P" factor sets in, due to assymetrical effect caused by the difference in push between the upward and downward going blades.
I didn´t know any of this, so I had to look it up.

Incidentally, yesterday, I contacted my old friend Udo Entenmann, the texture specialist, and he replied today. With a bit of luck, we could get some high quality Stearman textures done by him. Let´s see how it goes.

What still bothers me a bit are the engine bleeds at the cylinders. That will be a difficult one to tackle.

Cheers,
Aleatorylamp

[smilo]

the "drift" is a fact of life and is something
pilots have to learn how to deal with.
obviously, they can, do and did, else,
they would never get off the ground.
i think the stearman was a great tool
for teaching how to do it.
remember, she's a touchy ground looper.

am glad to hear you got in touch
with Udo Entenmann.
it must be a huge relief to know someone
who has the texturing skills.
years ago, it was PJ Dunbar,
but, sadly, he left simming
and all his techniques went with him.

as for the visual engine bleed problem,
i'm sure you will continue to work on it
and come up with the best possible solution.
if it ends up with a few bleeds,
it ends up with a few bleeds.
so it goes...you gave it your best shot.
if a critic wants to dwell on it,
they can either dwell on it,
or do a better job themselves
and share the technique.

[aleatorylamp]

Ha ha!, Smilo!
Thanks a lot for your suggestions!

It reminds me of a reply I sent, years ago, to a wise-guy who insitently e-mailed
me, seemingly to praise my AF99 work, but in reality to criticize me for not using
GMax on my "wonderful oldies that should get the proper treatment they deserve".

I diplomatically explained that I liked using AF99, and had no time for more detailed
work, but he insisted on the subject, adding that in fact, Gmax was so easy to use
that even he, who was "only" a mechanical engineer, used it every day in the office
to design mechanical parts like gears or crankshafts.

The e-mails promptly ceased when I told him to design the aircraft with GMax himself,
that it would be much easier than gears or crankshafts, and that the 3-view drawings
for them were readily available on the Internet!

Anyway... As regards the Stearman being a touchy ground-looper, you can feel the
torque effect during take-off, which becomes weaker as you gain speed. My experiments
with 280 and 360 Hp engines for this aircraft, show that the effect gets even stronger.

I understand what you mean, that it will be difficult to maintain some kind of temperamental
instability on the ground and during take-off, and then try to have stable behaviour during
flight. I agree that it would be quite contradictory.

So, as it does actually become smoother when cruising or flying at full speed, I suppose
that this was your reasoning behind your comment after some testing, and that you had
in fact decided that it was best left as it is. OK, then!
Any additional suggestions or ideas will of course be very welcome.

For the moment I´m just making some very fine adjustments to eliminate the 5%
extra power in all its modalities, because its implementation was more of a niusance than a
benefit.

There would be another question, as regards mixture control: There is no gauge that only gives
throttle and mixture control - they all include propeller pitch control. Would there be a point
in using auto-mixture, and a gauge with only throttle control, or would this be a sacrilege?

Thanks in advance for your opinion!

P.S.
Incidentally, the performance data quoted for the 7-cyl Continental engine in the CAA
certificate is straight forward and quite easy to get right, unlike the 9-cyl Lycoming, whose
data is for the moment ambiguous and impossible to reconcile.
Thus, we´re using Continental engines only, unless or until the other one clears up.
Update:
I´m quite pleased to say, without going into any detail, that performance results for the
Continental engine are extremely close to specification - almost perfect. It´s unbelievable!
Quite the contrary of what was happening with the Lycoming engine some time ago...

Cheers,
Aleatorylamp

[smilo]

many thanks for the chuckle.
for a moment, i thought the gmax guy,
you were referring to was me,
busily pushing ad2k on you.
you do see the similarity, right?

my line of thought
about keeping it simple
was, actually, based on early cfs experience.
it may be a gross generality,
but, let's just say, many didn't, or don't, care
about flight dynamics and engine torque.
what matters most is getting in the air,
going fast and shooting at stuff.
more's the better if one hits something
before one gets hit.
for me, it took spending time with hubbabubba
just flying around in multi player.
no shooting, just what he called "lazy flying",
before i started to appreciate the subtleties of the sim.
frankly, i don't know what people want or like anymore.
i know a lot of people look in on the cfs threads,
but, since they never comment,
i haven't a damned clue what they're thinking.
that's why i say, keep it simple
and please yourself.

ps...i guess i should make it perfectly clear,
if you want to talk about sacrilege,
you're talking to the wrong guy.
while i think it would be a cool skill to have,
i usually fly with auto mixture.
heck, i flew for years with auto rudder.
so, i'm the wrong one to ask.

although, i think it would be a cool thing
to have on the panel...just in case
someone wants to use it.
when i get a chance,
i'll look through my gauges
and see if i can help.

[aleatorylamp]

Hello Smilo,
It´s always interesting to have your point of view!

As regards my short story on the insistent GMax guy:
As is typical of me, I never think far enough to see possible lateral implications, and I see your point on the similitude with the AD2k issue. It was in no way intended of course, as you have noticed.
At any rate, your constant support and advice on the AD2k Electra project do make it very different!

About mixture control:
It seems that the real plane usually used full rich except for cruising,
so it would be quite easy to use, with a convenient gauge, of course.

Should you manage to find one, it would of course be wonderful, if it isn´t too much trouble.
If not, I´d say we could leave it at auto-mixture, because alternatively, doctoring up any existing gauges won´t help:

A) None of the default CFS1 gauge bitmaps helps, because the lever positions are different on the Stearman, i.e. throttle on the left and mixture closeby on the right.

B) Taking out the central pitch control lever from the default FSFS Conv. single-engined throttle quadrant, leaves a large ugly gap in the middle, and leaving it in, would be wrong.

OK, then. I already have some improvements - textures and .air file, so possibly I´ll post a WIP4 in the next few days.

Cheers,
Aleatorylamp

[aleatorylamp]

Hello All, hello Smilo!
WIP-4! Now there´s quite a bit more new stuff on the Army Corps Stearman-75:

The airplane is now fully textured, except for wing- and landing-gear struts.
They will hopefully not be the definitive ones as I´ve been able to contact my texture specialist friend who has offered to help out here.

There is also an exhaust pipe and an air-intake (un-textured as yet), but now we have a student-pilot, and can charge for flight training so our company doesn´t go broke.

I´ve managed to stop the concavity bleeds at the top-wing cut-out by simplifying the curvature. The shape is not as good as before, but definitely still acceptable.

Here´s the model for those who wish to have a closer look-see and try out the new .air file with more correct performance.

Cheers,
Aleatorylamp

[aleatorylamp]

Good morning!
It occurs to me that as we are playing with CFS, perhaps an additional, fully armed, more powerful fighter-bomber version would also be in order, like those units exported to South America for the air forces of countries like Cuba, Argentina, Brazil and Perú.
Cheers,
Aleatorylamp

[smilo]

grabbed the WIP4, but, haven't tried it yet.

have been thinking about an armed version
and can't come up with a positive use for it.
all i can see it as, is fodder, sorry.

i guess, back in the old days of multi-player,
sometimes, we would all fly sopwith camels.
it was fun, but, i doubt anyone does that anymore.

[aleatorylamp]

Hello Smilo,
I don´t know much about flying in multiplayer - I never dared -
so I´m not very well informed as regards simmers´ flying preferences.

Then in fact, I was never good at R/C flying either - I just built own
designs and tried flying them with limited success. Also, as soon as the
R/C Club announced a competition, I´d stop building until it was over!

OK, we don´t want a Stearman to be cannon fodder!
So we´ll stick to trainers, if only just for the historical importance the
plane had for the formation of those thousands of pilots!

Here it´s the Spanish national Holiday,
so I´m taking it even easier than normal...

The new air-intake in the nose is a structure for the moment, as I am
saving the 2 free components I have left for an eventuality. If I don´t
need them, I´ll make a slightly better shaped component for it.

I hope you enjoy the progressing Stearman-75 model.
Do tell me whatever catches your attention!
Thanks in advance! (no hurry...)
Cheers,
Aleatorylamp

[smilo]

funny that you should mention youth rc experiences.
that opens a big box of memories...
mine was a fly by wire bf109.
i loved running the .049 engine on the bench.
but, when it came to taking the model out
and actually flying it....never happened.
i was too afraid of crashing the thing.
stupid fear of failure.

now, building a model from scratch
like the balsa guillows kits
is on my bucket list.
i would also like to build a solid wood model,
but, they're both just in the dream stage.
we shall see if that ever happens.

[aleatorylamp]

Hello Smilo,
I made two control-line balsa models with the famous .049 too - a Bristol Box kite and a kind of Helldiver. Needless to say, I very soon crashed them. Then, the R/C ones, I crashed them all the time - I hardly landed them... I remember one I flew 8 times in one afternoon, crashed it 8 times, and fixed it with epoxy resin 8 times...

Well... Here are some screenshots of a Navy Version in provisional textures.
I noticed that the Units I wanted to have in the desired colour schemes (Army and Navy), had registration numbers of units with metal Mc-Cauley propellers, so "181" is a provisional registration number!

Definite numbering will be Army: "28" and Navy: "69".

A piece of excellent news is that friend Udo Entenmann is already working on the textures!
Cheers,
Aleatorylamp

[smilo]

WOW!...that will surely stand out in a crowd.
very nice.

[aleatorylamp]

Good morning, Smilo,
Glad you like it, and thanks for your good words!

I believe the Navy one was your preference, except for the blue rudder,
as it was the one in the picture in the original article you scanned. There
was a group of these named "Yellow Peril". Some name!

As Udo Entenmann is doing new textures and flies with FS98, I sent him
the model with the .air file of the red 450 Hp acrobatic cowled Stearman,
which flies rather well in FS98. However, I´ll try and adapt it for the
220 Hp now, just to be on the correct side.

I´m hearing from him on Sunday (tomorrow) about the new textures.

OK, have a nice weekend! Here we´re having another heat wave.
It is relentless, to say the least, despite Ophelia over the mid Atlantic.
Maybe it´ll start pouring and blowing shortly, but it appears it´s moving
north towards the Azores and Portugal, but we shall "Be Prepared", as the
Scouts would say!

Cheers,
Aleatorylamp

[smilo]

actually, i don't have a preference.
i look forward to both in my hanger.
but, if i did, it would be army air corps.
my father was air corps during WWII
and my uncle was air force from 1947.

the yellow peril sounds ominous,
for very good reason.
she was dangerous to anyone
who didn't respect her quirks.
(i wonder about the casualty rate)

i am anxious to see Ubo's work,
but, will be waiting patiently.

it has become full fledged fall here.
the days, usually warm and sunny
with occasional clouds and rain
and the nights in the mid thirties.
(that's fahrenheit)
gotta love those cool nights.
the leaves have been changing color
and falling for a couple months now.
depending on the type of tree.
the coral maple is dayglow yellow,
with subtle, red orange leaf tips.
flocks of geese fly over
heading for the pond up the road.
a safe place to spend the night.

[aleatorylamp]

Hello Smilo,
I have always liked forests and lakes. You are lucky - sounds like a beautiful area.
The time of the year and the scenery would inspire some Haiku!
As yet there´s no trace of Ophelia except for a few drops of rain at noon for 2 minutes...
We shall see.

Hello Folks,
So, the Stearman is progressing! Now all the aircraft is textured, and the
provisional textures for both Army Corps and Navy liveries are ready,
albeit still with the same provisional number "181"!

To keep texture nomenclature separate, there are two models, although they
are in effect identical, but both aircraft fit into one single CFS1 aircraft folder.
Thus, there are also two separate .air files.

The air intake now has an improved shape - it is a hybrid, with the body as a
component, and the scoop as a structure.

Parts count is at a modest 110.6%, and there are still 1 free component and 16
free structures left over. Extra ideas are of course welcome...

Here are is some eye-candy, as well as the WIP5 model. (I´ve had to withdraw
previous WIPs and some screenshots from older models to make space for
attachments - my space cuota had completely run out!).

Now is the phase of dealing with bugs and glitches, the hairline cracks and gaps
here and there, and any other flaws. Texture Friend Udo is working on the textures!

I suppose this will be the last WIP attachment. When I get all the minor stuff sorted
out and Udo´s textures are ready, I´ll upload the models. ...unless of course
something happens and puts a spanner in the works!

Cheers, and have a nice Sunday!
Aleatorylamp

[smilo]

i've got it, thank you, Stephan.
i'll try to have a look at it today,
in between winterization chores.
so much to get done,
before the rains come.

many find this area depressing
with all the clouds and rain.
me?...i'm partial to green.
more shades and textures
than one could ever imagine.
for the most part,
the climate is moderate.
not too hot,
not to cold.
like the baby bear's porridge,
it's just right.

[aleatorylamp]

Hello Smilo,
I prefer a bit of mist and rain to constant sunshine too. Today it´s a bit cooler and a bit cloudy, thanks to Ophelia´s passing by to the west of us, on its northward journey towards Europe.

I´ve just heard from Udo, and although he´s very busy workwise, he´ll be working on the textures in the next couple of weeks, which is great.

Another good piece of news is that with one able placement of a glue triangle, the forward crew-member´s head does not bleed through the fuselage seen from below-rear. I was quite surprised that it worked.

Now I have to try and work out a similar way to block the head-bleed when seen from lower-front.
Update: Partial success only! Head bleed´s gone, but now windscreen + cabinfloor bleed...
Aarrghh! But I´d more or less been expecting it...

Another minor bleed I eliminated with glue was the air-intake body and its scoop. I also got the curvature at the base much better. But... now there´s a wire behind the air intake that bleeds through it.
Let´s see if I can correct that now. No rest for the wicked!!

Here´s a close-up screenshot. You can see the wire I´m talking about...
You can also see the crew´s faces, which are Ivan´s pilot-heads and textures. I put in his propeller-blur too, which always comes in very handy.

Then I saw that the prop-blur was a bit smaller than the Aircraft Animator Propeller Disk. On the WIP5 model it shows on a close-up. ...or rather, it was the prop-disk that was too big:
AA defaults propdisk-size to one decimal place, here at 1.3 !
Changing it to 1.25 fixes the problem, though and now both sizes match, as seen on the screenshot.

Incidentally, I´d taken for granted that the instructor was in the rear cockpit, but there are pictures indicating that the front cockpit was for the instructor, the rear one being for the student.
On acrobatic models, however, you always see the pilot at the back, because of the view and the cleaner air, most probably.
So, for the time being, I have the virtual cockpit view set in the rear cockpit.
I suppose it would be correct that way...
Cheers,
Aleatorylamp

[aleatorylamp]

Hello all, hello Smilo!

Finally I found an effective way to eliminate all the head and Windscreen bleeds through the fuselage floor.

The fuselage is divided into sections, like slices, each slice having a head or a windscreen glued to the top,
the intention behind which is to prevent the upper parts bleeding through to the bottom. Sadly, this only worked for the slice itself. Heads and windscreens were bleeding through the floor of adjacent slices.

After splattering glue all over the place to no avail, trying to block off angular floor-bleeds between fuselage slices, it occurred to me to prolong the fuselage floor on each slice, i.e. duplicating floor pieces from adjacent slices forwards or backwards, depending on the position, and managed to block off the angular downward bleeds.

So that was very pleasing indeed, and there are no more floor-bleeds! See screenshots.
I just noticed a gap at the top of the outer wing-struts. Piece of cake, that one, no problem!
Now let´s see when we get Udo´s new textures!

Afterthought on the cylinder-heads:
Maybe it will look better to have their outward facing insignia parts in dark grey instead of black. Let´s see.

Cheers,
Aleatorylamp

[aleatorylamp]

Good afternoon, all, Good afternoon, Smilo!

Another bit of progress here, this time to do with two of the gauges.

I further improved the throttle gauge I had adapted from the generic
FSFS Conv thrust1 gauge, and it is now more realistic with a black
ball instead of a brown one.

Then, I adapted an ancient mixture gauge Smilo sent to me - thank
you very much, Smilo! I repaired the background to matches the
throttle gauge, and also gave it a red ball-handle, like on the photos.

The next step was to make a custom panel, a bit darker than the
provisional one I was using, and the result is now quite OK, I think.

The rest of the gauges are all default FS98 and CFS ones, and the
layout is in general what is shown on hotographs of the plane, except
for the autopilot. I left it in for the sake of comfort, but purists will most
probably want to take it out!

Here´s a screenshot!
Opinions and suggestions are of course, as always, very welcome!
Cheers,
Aleatorylamp

[aleatorylamp]

Hello Smilo,
After our e-mail discussions on what gauges to use on the Stearman,
I´ve taken out the redundant heading indicator, and also the autopilot,
for reasons of realism - sacrificing the comfy autopilot...
I only used it for fine-tuning anyway.

Then there´s the question of the scale on some of the compasses and
heading indicators, like you pointed out: Some seem to turn in the opposite
direction you´d expect, and some don´t! They move in favour of the aircraft´s
turning motion instead of against it! So, maybe that will need a change too.

Then I managed to get an extra texture onto the cockpits. They look quite
fitting, I thought, both from the virtual cockpìt view where the gauge panel
looks like tucked under the cockpit panelling, and from the outside as well.

Here are some screenshots. I think I´ll delete some of the older ones which
are not to the point anymore, so I don´t run out of attachment space anymore!

P.S. Update on Compass movement direction:
I saw a U-tube animation of a magnetic whiskey compass, and it also moved in the same
direction as the aircraft was turning, and this set my brain cogwheels into motion.

Imagine you were to hold a bowl of water in your hands, with a magnetic disc
floating in water. It would of course turn the opposite way to your turning direction.

But if you look at the edge of the disc nearest to you, it will move in the same direction
as your turning movement. The far edge would move in the opposite way.

So, depending on where a scrolling numbered scale were to be viewed from - the edge of
the disc nearest to you or furthest to you, a numbered scale would have to be written
differently.

I suppose displayed movement direction would depend on how exactly the mechanical parts
of the magnetic compass were built, i.e. where the movement is viewed from - from outside
the ring nearest to the viewer, or from inside the turning ring at the far side.

Then, an electronic display of a magnetic compass could be done in either direction.
In conclusion, it seems like both are correct!

Cheers,
Aleatorylamp.

[smilo]

excellent explanation of compass views.
it makes sense. thank you.

so, fortunately, cfs has examples of both.
allied whiskey indicators move in one direction,
where as, german turn the opposite.
(maybe, that was what WWII was really all about)
anyway, when i bank left or right,
i want to see the increments move
in the direction i'm turning.

therefore, i lean toward the german heading indicator.
but, that's my personal preference
and is, by no means, an indication
that i subscribe to the line of thought.
quite the opposite