Jafo
SOH-CM-2024
Yes, it's all over the place like a mad woman's breakfast...Ah, the Voodoo. Such a sexy plane, but such an awful main panel layout...
Yes, it's all over the place like a mad woman's breakfast...Ah, the Voodoo. Such a sexy plane, but such an awful main panel layout...
Yes, it's all over the place like a mad woman's breakfast...![]()
EPR is Exhaust Pressure Ratio. Basically a comparison of the pressures between the front and back of the engine expressed as a ratio with the front being 1 and the back being a variable based on temperature and altitude. This value is used to determine the maximum power setting for what ever phase of flight you are in. Such as takeoff, climb, cruise and go around. The pilot in this case would view a performance chart to determine the max epr setting that is allowed. For example we will use takeoff. If his chart indicates that for the outside air temp and his altitude his max allowable epr is 1.95, he would then on his epr gauge as part of his cockpit setup would rotate a small knob an the gauge, this would cause a small pointer to move on the inside face of his gauge. He would move this to the indicated value he obtained from the chart. When the pointer is moved the numbers in the window on the gauge face move as well to show him the numerical value the pointer is set at. Most people in the flight sim world when making an epr gauge have completely blown this. The pointer and epr numbers do not move when engine power is changed. It completely possible to overboost the engine in a manner of speaking, by pushing the power up above the published max epr setting. For example if you you had a max epr value of 1.65 for climb it was possible to push the engine up to 1.75 or so giving a potential dangerous condition. I've include a sample from a DC-8-62 flight manual to show an example of a takeoff power setting epr chart and an excerpt from a DC8 training manual for more clarification.
Most people in the flight sim world when making an epr gauge have completely blown this. The pointer and epr numbers do not move when engine power is changed. It completely possible to overboost the engine in a manner of speaking, by pushing the power up above the published max epr setting. For example if you you had a max epr value of 1.65 for climb it was possible to push the engine up to 1.75 or so giving a potential dangerous condition.
John....yes, I know what it is.....but what I want is simple [not to me] XML coding that can be used to rotate that bug [and the analogue number drums] to that preset...not the methodology of calculating the preset.
In this case the intent is to have the gauge 'interactive' as typically an EPR gauge in these aircraft simply has a drawn [or photographed] static bug and numbers...they 'DO' nothing.
I want to be able to click down/up on a 'knob' and see the pointer and numbers change, that's all...
All my gauge work is done by converting and adapting...I can't code from scratch.....when I went to school 'coding' was done with punch cards and a paper clip...![]()
What does the real system do anyway? Does it just provide pointers for the pilot or does it provide an actual stopping point for the engines, i.e. can the pilot in the real thing push the engines beyond the EPR bug setting or not?
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I think they can be pushed past... In the Thud there are two bugs...one for Take-off and one for cruise....and it would make sense that the lower 'cruise' set bug could be pushed through...to get to takeoff...
I'll have a look at your link...but remember....all I am looking for is a clickable input that does NOTHING other than move a bug around a dial...NOT change system limitations like a decision height 'bug' would...if you used that var as a clicked input to move a bug.
I ONLY want the bug to move position visually...on clicked input..and do nothing else.
Here's the gauge...in the panel...it's circled...it responds to throttle input etc....but at the moment has no 'bugs' or drum roll numbers.
View attachment 9796
This Panel is about as extreme as it gets...even the gauge reflections in the cockpit glass 'function' mirrored......oh, and that map...it's a fair-dinkum map...of Nth Vietnam...![]()
The movable pointer is just that. A reference, you can definitely push past the reference bug with possible dire consequences. If an autothrotle is installed on the older aircraft it works off of indicated airspeed.
Almost done....all I'm missing is the right syntax to have both left click and right click functions on the Knob...so I can move both bugs...![]()
Well, you'd need to split the mouse area for the EPR bug knob into four mouse areas. Just take the existing two areas and split their height in half, then copy them and move their position downward by one time the new height. Then change the L: var of two of these mouse areas to "(L:EPRPRESET02, number)". Clone the EPR bug's entire "<element>" section and have (L:EPRPRESET02, number) drive its animation.
Maybe you should alter the the color of the second EPR marker to have two distinct ones.
It's not as hard as I make it sound.</element>
HvyEng:
Legitimate outputs are doable with accurate FDE data, a "N1-EPR" table and a bit of gauge magic. I have in fact spent a metric ton of time and made Tom Ruth's 727 pretty much "flyable by the charts".