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-   -   Flightsim-pilot questions (Merged) (https://www.pprune.org/rotorheads/235839-flightsim-pilot-questions-merged.html)

that chinese fella 5th Jul 2006 04:03

The 1 minute time before switching the generator ON is only applicable if the engine has been shut down for more than 15 minutes. See the "Caution" caption of the Start procedure in the AFM.

Patrick_Waugh 12th Jul 2006 00:05

Request - Pic of panel b206 at night
 
I need to know what the instrument lighting is like on the B206 to sim it.

Anyone have a pic of the instruments at night to give me an idea?

Patrick

Jez 12th Jul 2006 06:13

Why not "sim" an AS355N? It is a "staged" shot but doesn't look too bad.

http://i96.photobucket.com/albums/l1...5/819c82b6.jpg

Brilliant Stuff 12th Jul 2006 10:51

Love the boat. Nice shot.

Patrick_Waugh 12th Jul 2006 16:41

That is a gorgeous picture. And helps to give me some ideas of the lighting.

I would love to sim the AS365, and perhaps will do one next. First I have to get one done to fund further development. Right now, I'm looking into doing custom instruments for people.

Patrick

helicopter-redeye 12th Jul 2006 18:10

Can you not just take the one from MS Flight Sim and use that. ?

h-r;)

Chiplight 12th Jul 2006 19:04

n206 panel lighting
 
Here's something...

http://www.henry1.com/nvg/407_NVG_panel_0418.jpg

Patrick_Waugh 12th Jul 2006 22:32

Hmmm this is a 407, but also gives me ideas.

Someone asked why I can't use something for FS. Well, the lighting used in default aircraft is very primative, and is already available in the gauges I have created, but I am using programming tecniques to go beyond their capabilities to add reality.

I guess in the end, it depends on the instruments you have installed, and if they are designed with lighting at all.

Patrick

John Eacott 14th Jul 2006 08:19

Patrick,

Not the best shots, but these may help you:

http://www.helicopterservice.com.au/...0panel%201.jpg




http://www.helicopterservice.com.au/...0panel%202.jpg


http://www.helicopterservice.com.au/...GT%20panel.jpg

Patrick_Waugh 14th Jul 2006 18:20

Thanks.

Those do help considerably. It appears that internal light instruments have a light in them near the top that illuminates that instrument.

For the attitude indicator that has no internal light, post lights were added to put crossing mini spots on it.

Thanks again,

Patrick

Patrick_Waugh 17th Jul 2006 17:06

Electric gyro questions
 
I have a few questions for someone patient enough to put up with them.

All of the following questions assume an attitude indicator in a helicopter (B206), that is driven by an electric gyro.

1) First, is there always a "pull to cage" knob? I have seen some photos without one I think. I am guessing that if there is not it is because the gyro is incapable of tumbling, and hence does not need it. I would also expect that it would be rare to see one in a helicopter as it rarely would exceed certain bank and pitch limits. If you do cage one, do you need to do this in level flight?

2) If you were to not turn on the gyro during start, but waited till you were in an established constant turn at say 10 degree right bank, and then flipped on the gyro and allowed it to spin up before leveling out, would it then assume that was level, and hence now indicate a bank in the opposite direction?

3) When it is not functional, is there a warning flag? Does the flag say "OFF"? Does it go away right away on power on, or wait until the gyro spins up? When the gyro fails, how long would it take you to notice it spinning down (if the flag were not telling you immediately)?

4) Thanks.

Patrick

http://home.comcast.net/~pwaugh/pics/AttitudeAvitar.gif

skastdk 17th Jul 2006 17:51

After you spin up the gyro on the ground, you will ned to cage it with the knob! To set it level!

Depending on the gyro system, if you cage it in a turn, it will show a wrong indication when you level out!

You can have different warning flags, but an off flag (orange) could show in top right hand corner!

Some attitude indicators spin at aprox, 18000 to 22000 Rpm, hence it will take a little while for it to slow down! But the flag will show right away!

http://www.faa.gov/library/manuals/a...ying_handbook/

Avnx EO 17th Jul 2006 18:30

This is probably more detailed than you were looking for .... but here goes....
All mechanical gyros drift over time and require some form of correction. Vertical gyros used for attitude indicators have a biasing mechanism that over time keeps the gyro "dirty side down". That biasing mechanism is based on the assumption that over the long term, the aircraft is straight and level. A lot of times these are mercury switches that apply an small electromagnetic force until the mercury switch centers (gravity down)
So if you were to fly any aircraft in a constant co-ordinated turn long enough, the gyro would eventually re-align and show level flight while in the turn.
So when you start up a gyro, you have to have some form of mechanism to get it where you want quickly, otherwise you'd have to wait for this biasing mechanism to work itself out before you could take off. For mechanical attitude indicators, the common means is to cage (mechanically force) the indicator to straight and level. Other remote gyros had a "fast erect" switch (Viagra for gyros) that dramatically reduced the time required for the biasing mechanism to drive the gyro to the desired position.
Later AHRS (Attitude heading reference systems) perform automatic alignments on power up, so you don't even have to cage or "fast erect." Instead, if the AHRS sees a relatively stable input from its gravity sensors after power up, it automatically performs the equivalent of a "fast erect". Usually when you are talking AHRS though, the sensors are either FOG or MEMs type and you don't really have anything moving anymore. It's all done in math.
That all said, I suppose there might be some mechanical gyros that automatically cage when power is removed. None of the mechanical units I'm aware of, though, seem to have this feature.
Hope that helps you out.

Avnx EO 17th Jul 2006 18:34

One more thing.... If it's the Bell-installed attitude indicator... the off flag is a red and white striped barber pole.

Gaseous 17th Jul 2006 19:46

Avnx has done a very thorough job of it. The only thing I can add is that some older gyros use jets of air to bias them. There is a fan on the rotor which is ducted through holes to give air jets. There are pendulums with shutters which partially cover the holes, and when the gyro is erect, all is in equilibrium. The air jets cancel each other out. If the gyro is not erect the pendulums move, the shutters cover some, and uncover the opposing jets, which applies force to the rotor until the equilibrium is re-established. Caging it forces the gyro erect by brute force. I have seen some of this type of instrument with no cage knob but they are pretty old. They are certainly capable of 'tumbling' and you just have to wait until they sort themselves out if they do!!

Patrick_Waugh 17th Jul 2006 20:04

Thanks. I appreciate all the detail.

Helps to make the sim instrument.

Patrick_Waugh 17th Jul 2006 22:11

Thunderstorm lights
 
Seems a thing called "thunderstrom lights" is required by the FAA for IFR helicopter operations in the US.

Anyone tell me what those are?

Patrick

http://home.comcast.net/~pwaugh/pics/AttitudeAvitar.gif

212man 17th Jul 2006 22:18

They are very bright cockpit flood lights, used at night or in poor lighting to bring your eyes' sensitivity to near daylight levels when flying in the viscinity of electrical storms. This prevents you from becoming blinded by nearby lightning flashes, which would be the case if you had allowed your eyes to becoming 'night acclimatised'.

Personally, if the lightning is that close I have my eyes shut anyway......:\

Patrick_Waugh 17th Jul 2006 22:35


Originally Posted by 212man
They are very bright cockpit flood lights, used at night or in poor lighting to bring your eyes' sensitivity to near daylight levels when flying in the viscinity of electrical storms. This prevents you from becoming blinded by nearby lightning flashes, which would be the case if you had allowed your eyes to becoming 'night acclimatised'.

Personally, if the lightning is that close I have my eyes shut anyway......:\

Hahahahhhahahaha.

Ok, makes perfect sense. Thanks. Also explains why I couldn't find a thing on them searching google with "aircraft exterior lights".

Patrick

SASless 17th Jul 2006 22:37

212man is being polite....they are commonly known as "anti-dazzle" lights (UK lingo)....and all the time I thought they were just there to blank out the two big white serving plate orbs shining back at me on the windscreen.


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