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c172p-team / c172p

A high detailed version of the Cessna 172P aircraft for FlightGear
GNU General Public License v2.0
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Preflighting the C172 with outside view #724

Closed tigert closed 6 years ago

tigert commented 8 years ago

So I took this for a test flight and preflight today. A few notes:

tigert commented 8 years ago

By the way, is it possible to show SVG in the dialogs? I could make a fuel drain tube graphics with "clear" blue avgas and contaminated one with water bubbles in the fuel?

gilbertohasnofb commented 8 years ago

The fuel tank quantity and sampling dialogs are neat. However the quantity could be also shown in liters in addition to gallons and pounds.

Thanks! :smile: I will add the quantity in litres later today

Fuel sump clickpoint is a bit hard to find, maybe combine all fuel related stuff to one dialog and tie it to a big clickspot on the fuel tank itself? So that it shows quantity and lets you take the sample as well.

Actually the clickspot for the fuel sumps is quite large, the problem may be that if the camera is below the surface, the clickpoints do not work (FG thinks you are clicking on the terrain itself). As for combining the fuel sump dialog together with the refuelling dialog, I strongly disagree with that.

As for the other suggestions, I don't have any knowledge about them.

gilbertohasnofb commented 8 years ago

Here is an idea to make finding the fuel sump drains easier: maybe we could model a simple fuel sump drain as a 3D model under the wing, so that it would stand out. We could also add a 2D plane with a sign for it. See:

If @wlbragg or @onox are up for it, I can prepare textures.

wkitty42 commented 8 years ago

On 03/02/2016 03:30 AM, Tuomas Kuosmanen wrote:

  • Is there a way to disable clicspots (and tooltips) from within the cockpit when you are in an outside view? There is a lot of stuff that is clickable and shows tooltips in the cockpit that gets in the way when you try to do a preflight check in an outside view. Same with outside clickspots when you are in the cockpi. I often accidentally clicked the engine oil clickspot when I used the GNS196.

i highly doubt it... why? in most any craft, if you CTRL-C to turn on the hotspots and then you 'V' to jump outside, you will see clickable yellow spots from the interior all over the outside through the exterior skin from many different angles... i asked about this before and there was not much of a satisfying response... not whether seeing them from outside was a problem in the 3D model rendering or if it was simply a bleed through situation...

gilbertohasnofb commented 8 years ago

i asked about this before and there was not much of a satisfying response... not whether seeing them from outside was a problem in the 3D model rendering or if it was simply a bleed through situation...

I don't know why you didn't find the response to your satisfaction, but I believe we spoke that this is a feature not a bug: because the click spots are available "through" the aircraft (e.g. you can click on the oil door fro inside the cockpit), so are the hotspots yellow markings visible through the aircraft. AFAIK every single aircraft in FG behaves this way, and if you have some idea on how to improve this then the place to discuss it is the dev mailing list I believe.

tigert commented 8 years ago

Yeah, the clickspots inside the cockpit make less sense when clicked from outside, because the objects are very small and you don't really poke at stuff inside the cockpit when you are doing a walkaround anyway. And vice versa, the oil check clickspot is exactly behind the GPS196 buttons, so that is very annoying in practice. And you should not really need to poke at the external clickspots when you are in the cockpit anyway. Maybe this is a limitation of how flightgear works, and while it migth be possible to do some NASAL checking for which view you might be and enabling and disablign the spots accordingly, it probably is best to fix at flightgear level once and for all aircraft.

One thing we could of course have is a preflight walkaround system created from custom camera views and a checklist buttons where you go through the external preflight checklist and it moves you to the views where you can actually see the items to check for, and maybe even has the magenta circles to show where the things to check are located. The walker is a bit confusing to me, sadly I have never really successfully operated it the way I want.

Fuel drains: Luckily we don't model the later model C172's, those have 5 (FIVE!) fuel sumps per tank, so there is eleven places you need to drain to check for water contamination if I remember correctly... The C172P I think has only two per tank.

But the C172 also has a drain sump under the front fuselage, behind the nosewheel, and one strainer valve with an outlet near the nosewheel that is operated via a pull-lever near the oil dipstick (under the same cowling door IIRC) - pulling that drains a bit of fuel from under the belly. (That's a nasty one to sample because you need to "hug" the engine by holding a cup below the drain line with your left hand, and pull the lever up (!) with your right hand - sadly most people just drain a puddle to the tarmac and smell that it is gasoline, bad for all the lead going into the ground)

The tank sumps typically look like this: http://www.sportys.com/media/catalog/product/7/5/7506a-multisump.jpg It is a hex nut with the hole and vent within, and the fuel tester has a stick that you poke in to push against a spring, to open the valve. You take a bit of fuel in, and see whether there is water (clear bubbles) inside - this is why avgas is blue, so it is easier to see the water bubbles. (JET A-1 (kerosene) is clear, so it is more difficult to spot water in it.)

Anyway, it might be nice to have some custom camera views for this if that would be possible to do?

.. maybe one to check wingtips for working navigation and landing lights etc.. how far do we want to go with this? :-) Poke the flaps to see if they have too much slack? Whether the pushrods are in place?

Anyway, I think something like this might be fun, but the system should be convenient to use before we make it too detailed, and it should have the "do this for me" button in the checklist.

tigert commented 8 years ago

How do you get water to the fuel system by the way? Completely random? Does it take rainy weather into account? If you leave it there, what happens?

gilbertohasnofb commented 8 years ago

The walker is a bit confusing to me, sadly I have never really successfully operated it the way I want.

Why is that? I find the model of the walker very ugly, but it works quite well for me

But the C172 also has a drain sump under the front fuselage, behind the nosewheel,

To which tank is that connected then?

The tank sumps typically look like this:

So I am up for creating a 3D hex nut to make the clicking spot a bit more obvious, but I would still leave the huge hotspot area there.

Anyway, it might be nice to have some custom camera views for this if that would be possible to do?

That's possible, but I am not convinced that's really necessary. That would "pollute" the view list with tons of new views, and all these clickspots are available using either the walker or also by simply using teh external view.

How do you get water to the fuel system by the way? Completely random? Does it take rainy weather into account? If you leave it there, what happens?

It's just random, I think with a chance of 1 in a 100. Taking weather into consideration is tricky because it's not only the current weather that would affect it, but yesterday's weather :wink: I think the random solution is fine because it's simple and forces the pilot to create the habit of checking the airplane just like in RL.

tigert commented 8 years ago

See the POH page 7-22. http://holladayaviation.com/files/Cessna_172_C172P-1982-POH.pdf

The bottom fuel sump is in the fuel selector valve it seems, which is one of the lower points of the fuel system (where water would end up in, as it is heavier than gasoline).

The strainer is close to the carburettor, so both are conceptually after the fuel valve, thus where there is only one valve. Maybe model water in the reservoir tank and have it cleared when you drain both the strainer and the belly sump? It doesnt necessarily need to be accurate, since it does not really matter which one of those contains water, since all of the fuel system water would need to end up in the carburettor and to the engine to be a problem.

wlbragg commented 8 years ago

I can add the drain hex nut.

As far as the hotspots being activated through the aircraft from the outside, off the top of my head it may be possible to disable the tooltip when in the exterior view, like we do for the second glass layer. Beings there is a disable tool tips in the gui you could activate that on external view, but then you would loose the external tool tips as well. I have on occasion had the tool tip pop up at an inconvenient place and time and it is annoying.

gilbertohasnofb commented 8 years ago

@tigert The problem with modelling the water in the tanks is that it adds complications: as I mentioned before, the water accumulation is something that can happened in the night before, if it was rainy and the aircraft was stored outdoors for instance, and there is no way to simulate this sort of thing, hence why a 1 in 100 random chance seems like a fair compromise, since it forces you to make the checks and giving you an occasional fuel contamination while not overcomplicating things.

So what about this: what if this bottom fuel sump will show contamination if and only if at least one of the tanks is contaminated, but not always? That is, if one of the tanks is contaminated, then there is a chance that the bottom fuel sump will also be contaminated.

@wlbragg we can add these hex nuts, as well as the new hotspot for the bottom fuel sump. As for disabling the hotspots depending on the views, IMO this can lead to much more problems than we have in the first place. We would need to specify which views forbid the tooltips and hotspots for the conditionals, but then again users can define their own views. Imagine for instance someone defined a view for the radio stack, but then this view isn't the "cockpit view" and so it may break all hotspots in the cockpit.

gilbertohasnofb commented 8 years ago

@tigert one more thing, about your request to have fuel in litres: FlightGear does not currently have a property for that in the property tree (at least AFAIK), nor does it show fuel in litres in the default fuel and payload dialog. Surely it would be easy enough to convert gallons to litres, but probably a better approach would be to ask the devs to add this property directly to FG's code, as well as add the fuel in litres to the already mentioned dialog. I will write to the mailing list about it, but I'd like to know how common is to deal with fuel in litres. Is it the standard in Europe? @Juanvvc would you know about it? Because if it is, then it should be easier to convince someone to do this modification to the source code.

Juanvvc commented 8 years ago

I and all the pilots I know use only gallons. Of course, showing litres as well as gallons is a nice improvement.

Since the conversion litres/gallons is trivial and used only in a dialog, in my opinion it is something that should be done in nasal and not the internal FG code.

gilbertohasnofb commented 8 years ago

I and all the pilots I know use only gallons.

Well, in that case we have to see what to do, personally I think the less cluttered these dialogs are, the better.

Since the conversion litres/gallons is trivial and used only in a dialog, in my opinion it is something that should be done in nasal and not the internal FG code.

Well, what I wrote was that IF we want to have fuel in litres as well, then the modification could be done not only in the c172p fuel dialog (which I created) but also in the default fuel and payload dialog (for all aircraft). So that would require anyway a modification to FGDATA. And given that all these unities for fuel are exposed in the property tree (gal, kg, pounds) then it would make sense to add one more.

But if using litres isn't really that common, I would honestly just keep things as they are.

wlbragg commented 8 years ago

We would need to specify which views forbid the tooltips and hotspots for the conditionals,

I'm not pushing for this, just putting it out there. We use only one conditional for determining and exterior view for the glass and have so far had no trouble with it. Then if we added one more conditional, AGL > 0 we could account for all the tooltips we still want to show on a ground inspection. Just a thought.

gilbertohasnofb commented 8 years ago

I think I already added this for all securing objects (tie-downs, chocks and pitot tube cover): their tooltips are removed once the airspeed it higher than a very low threshold.

wlbragg commented 8 years ago

I see, maybe "best practices" is to set up a condition per tool-tip to limit when it can be viewed?

gilbertohasnofb commented 8 years ago

We can try doing that. We can also hide the hotspots themselves, so that Ctrl+C wouldn't show them as well as hoovering the mouse above them wouldn't change the cursor as if they would be clickable. If a hotspot is hidden with a conditional, then probably nothing needs to be done about the tooltip since it's tied to the hotspot itself. What do you think?

If we decide to do this, then I suggest we open a new issue specifically for it.

wlbragg commented 8 years ago

. If a hotspot is hidden with a conditional, then probably nothing needs to be done about the tooltip since it's tied to the hotspot itself.

I think that sounds right. I guess we just need to decide whether its worth the effort. Surely we're not the first to question how to deal with this. I'll start paying closer attention to existing aircraft with hot-spots and tool tips and see if any of them are handling this with conditional or from and external view. That's the only time I've ever been annoyed by it, when taking pictures in an exterior view and suddenly a tool-tip for some switch pops up.

gilbertohasnofb commented 8 years ago

Personally they do not annoy me, and indeed it will be quite a lot of work of tracking every single hotspot and tooltip around the aircraft. If the majority of the team decides to do it, then I'd be glad to help with, but my vote is to leave things as they are

gilbertohasnofb commented 8 years ago

@onox any opinions on this?

tigert commented 8 years ago

Yeah, it depends usually on the operating handbook of the aircrat (and the fuel planning Excel file :-))

Our Cessnas had the fuel planning stuff in liters, but the Diamond DA40 fuel probe (and the G1000 fuel totalizer) show everything in gallons.

It would be just fine to do the conversion for the dialog in nasal, would be just convenient.

http://kaltsi.github.io/Mass-and-Balance/oh-srh.html <- our Cessna's mass and balance calculator. We could adapt this to the PHI by the way..? The code was written by my friend, and it's here: https://github.com/kaltsi/Mass-and-Balance

That one is very handy and shows the mass and balance graph. It is fairly generic and uses "spec files" for each aircraft separate from the code, so it could adapt to whatever aircraft you have in FG.

dionyziz commented 6 years ago

For what it's worth, we use liters when filling up the C172Ms at the LGTT GA clubs. It may be a Europe thing.

gilbertohasnofb commented 6 years ago

@dionyziz Thanks for the input. I am improving the fuel dialog to also show fuel in litres and also to show the baggage weight in kg.

gilbertohasnofb commented 6 years ago

Done, see commit https://github.com/c172p-team/c172p/pull/1181/commits/931165d1c2a57da653d64e35da8ffa78c091f289

I think this solves this issue completely, all the rest seems to already be implemented.