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Fredflyer
22 Oct 2007, 16:33
Hi everyone,
i have a problem with flaps variables and probably someone could help me.

for flaps we have those variables :
- FLAPS HANDLE INDEX which gives the current position of flaps or selected)
- FLAPS HANDLE PERCENT which gives the percent of the current flap position (or selected)
- TRAILING EDGE FLAPS LEFT PERCENT (or RIGHT) which give the flap position when maneuvering.

My problem is that this last variable, depending on aircraft is not the same value than the flaps handle percent, when the flap is in his positions.

for example, with the BE58 i have :
position 0, percent 0 and the trailing edge goes to 0
position 1, percent 0.5 and the trailing edge goes to 0.5
position 2, percent 1 and the trailing edge goes to 1

but with the PA28 i have
position 0, percent 0 and the trailing edge goes to 0
position 1, percent 0.5 and the trailing edge goes to 0.2424 :confused:
position 2, percent 1 and the trailing edge goes to 1

how can you explain that ?
is there any formula to calculate or guess the rtailing value for the flap position ?

thank's for helping me

Pete Dowson
22 Oct 2007, 19:05
My problem is that this last variable, depending on aircraft is not the same value than the flaps handle percent, when the flap is in his positions.

Why is that a problem? One gives the HANDLE position, the other gives the FLAPS position. They scaling of the handle need not correspond with the angle of the flaps.

is there any formula to calculate or guess the rtailing value for the flap position ?

I always thought it was defined in the AIRCRAFT.CFG file, as in this part for the PA28:

[flaps.0]
type = 1 // 1 - tail, 2 - lead
span-outboard = 0.587 // 0.0 .. 1.0
extending-time = 5 // seconds
flaps-position.0 = 0 // degrees, KIAS
flaps-position.1 = 10 // degrees, KIAS
flaps-position.2 = 25 // degrees, KIAS
flaps-position.3 = 40 // degrees, KIAS
damaging-speed = 100 // KIAS
blowout-speed = 120 // KIAS
lift_scalar = 1.0
drag_scalar = 1.0
pitch_scalar= 1.0
system_type = 3 //0=Electric, 1=Hydraulic, 2=Pneumatic, 3=Manual, 4=None

Looks like your position 1 equates to 10 degrees which is 25% (not sure why you get 0.2424 but it's close -- maybe absolutely full is a bit more than 40 degrees).

However you should find a position 2 at 25/40, or 62.5% (0.625). How come you only found 3 positions, not 4?

Pete

Fredflyer
23 Oct 2007, 01:52
Thank's Pete,

it's what i saw in the aircraft.cfg but didn't think of this angle ratio...:p
it was such in front of my eyes probably....:cool:
well, i 'll try to work with these values because now i'm quiet sure that this is the solution of my problem
3 positions of flaps than 4 ? well id don't really know...when youy use the PA28 in FS (9 or X) and use the flaps leveller (using the mouse), you only have 3 positions even if there are 4 described in the aircraft cfg....:rolleyes:
strange...maybe it's an old bug never reported or corrected...

Pete Dowson
23 Oct 2007, 05:15
when youy use the PA28 in FS (9 or X) and use the flaps leveller (using the mouse), you only have 3 positions even if there are 4 described in the aircraft cfg....:rolleyes:

The only PA28's I have are add-ons with panels which look like they've been made using assorted parts, including from the Cessna. Certainly the PA28 flaps lever here has 4 positions. I suspect you are looking at an added-on aircraft with an Aircraft.CFG not really matching its panel correctly?

If you have a registered FSUIPC it will show you the number of flap positions FS knows about, for the aircraft when loaded, in the Joystick Calibration section for flaps.

Regards

Pete

Pete Dowson
23 Oct 2007, 06:04
On this matter:

I suspect you are looking at an added-on aircraft with an Aircraft.CFG not really matching its panel correctly?

I found this, relating to the PA28 Cherokee series, on Wikipaedia:

The pilot operates the flaps manually using a large lever located between the front seats: for zero degrees the lever is flat against the floor and is pulled up to select the detent positions of 10º, 25º and 40º. The flaps can also be manually held at an angle slightly exceeding the 40º available in the last detent.

So, there should be 4 positions, 0, 10, 25, and 40, exactly as per the CFG file. The 0.2424 ratio you get from the 10 degree position results from the full down being greater than 40 when "manually held". I'd make that about 41.254 degrees for 0.2424.

I think it seems pretty clear you have an incorrect panel for your model, or at least the flaps part of it. ;-)

Regards

Pete

Fredflyer
23 Oct 2007, 13:43
thank you again for these explanations and complete informations, but the only PA28 i have in FS (9 or X) is the standard one, installed by the microsoft software: the PA28-180.Nothing else and no addon at all...

Pete Dowson
23 Oct 2007, 19:35
thank you again for these explanations and complete informations, but the only PA28 i have in FS (9 or X) is the standard one, installed by the microsoft software: the PA28-180.Nothing else and no addon at all...

Hmm ... the only default PA28 installed is for AI traffic use. It installs with no panel file whatsoever, not even a panel folder. It sounds like you've made the one intended just for AI use user-flyable by adding a panel, or aliassing it to another, but evidently not the right panel for the aircraft.

Regards

Pete

Fredflyer
24 Oct 2007, 02:09
Ooooh...poor Fred...he was a good boy but so englued with his problem that he couldn't make the difference between a PA28 and...a Mooney Bravo !:o
i don't know why i was focused on that plane name...
i'm really sorry...
i'm going to watch the good aircraft cfg file to understand the values i was looking for.
it's when you told me that the PA28 was an AI aircraft that i wondered if i was dreaming or not...i went on wikipedia site to get the list of FS airplanes and saw that you were right, even if i knew that you know everything on all fs versions...
thank's a lot to give me the rigth way and to understand my mistake.
see you next time for another real problem with the good inputs...:)