Dutch wrote:

So, to sum up, it's not the status of whether you're on the ground or not as I had guessed.  The pressurization system is working (the system is adjusting the cabin altitude towards the selected goal by the chosen rate) when either or both of the packs are on and the airplane is sealed up.  

Negative pressure is not allowed. A relief valve will see to that.

The system does not start to adjust the cabin just sitting there on the ramp. Sure, you could start the cabin down and increase pressure, but remember the limit of .125 psi. It is after you takeoff that the system starts to do its thing.
The altitude you select in the auto controller and the rate will start the cabin to climb as the plane climbs, but at a much slower rate. The goal is to climb the cabin at a smooth steady rate of lets say 300 to 500 fpm and arrive at the selected cabin altitude before the plane gets to its cruising altitude. Example: aircraft at 35,000 feet, cabin at 7,000 feet - differential pressure around 8 psi.

When no packs are on, or the doors are open, the goal becomes the outside air pressure.  With packs off but cabin sealed, use the rate selected.  If a door is open, it's much more rapid.

With no packs on and doors open inside is the same as outside. With packs off and all doors closed technically you get a slight negative pressure from the equipment cooling fan, but that is too much detail.

Manual overrides auto and sets rate independent of the normal rate dial - unless manual switch is in the auto range.

Correct! With the Manual needle in the 12 o'clock position the auto controller is boss. If you move the manual knob out of that middle position the auto controller is overridden and slowly the manual controller takes over.

Pressure differential can not be negative and not exceed 9 PSI (what happens if it does?)

Yup! That is true. If in auto control and 8.4 is neared, the auto relief valve starts to work to cap the differential. If you exceed 9. something, the manual relief valve comes into play and the correction is a lot bigger. Not a good place to be with passengers on board as there will surly be some laundry issues.

I love the level of detail in your reply, but I'm not going to try and implement all that.   At this point I just want a reasonably accurate implementation.  

We bump up against the fact that as simmers we are a one-man show trying to run a three-man airplane.   When I'm flying I can't be riding herd over this pressure controller to be smoothing out pressure bumps -- I'd probably crash while staring at the FE panel.  I've stalled once and crashed while testing!  Was annoying...

When I fly the 727 or 707 of Captain Sim, I don't worry too much about the F/E panel. I keep an eye on the fuel on a long trip and cross feed when needed, but as you said - I did enough of that F/E stuff to last a life time.

How about this for a workable mini-checklist.

1.  After engines are started and cabin sealed, set pressure goal 1,000 feet or so above field elevation and rate at 300-500FPM.

2.  Once established in the initial climb phase, set pressure goal to what you'll want it to be at cruise and let it start rising.

3.  At top of descent, set pressure to 1,000 feet above field level and rate to 200-300 FPM.  Try to avoid letting the airplane get ahead of the system, but let the controller itself prevent negative differentials on the way down.

4.  After landing set pressure to field elevation so as not to induce a surge when the doors get opened.

This may be a little more semi-automatic than the real thing, but still operated in basically the same way.  It should keep the altitude, rate of change and differential numbers within a reasonable range, without the huge amount of work, which is good enough for me while we wait for Captain Sim to fix it officially.

1. OK
2. OK
3. Set the auto controller to the landing field elevation. Keep ahead of the plane at ALL times or we are back to the Laundromat issue. These relief valves are pretty savage. Nothing subtle in their corrections.
4. If you do 3 correctly you have done 4!  ;)

Lou  8-)