Pressure Altitude

If you are already there, you can just set your altimeter to 29.92.

or formula time

29.92 - current barometric pressure, x 1000 plus elevation = PA

For my local field right now

29.92
- 29.83
= .09
* 1000
= 90
+ elevation (1253 field)
PA = 1343
 
:o You know, I am pretty sure I could have actually answered your question by saying...
You find it at altitude the same way you find it at field elevation; replacing field with altitude.
 
N18040 said:
Really? I guess that most of my flying is done at 1200 Pressure altitude. I thought it would change when I was at a different altitude, but I guess not.
Click to expand...

Ever used a GTX327 or 330? They both have the capability to display pressure altitude, as does the G1000 system.
 
N18040 said:
Really? I guess that most of my flying is done at 1200 Pressure altitude. I thought it would change when I was at a different altitude, but I guess not.
Click to expand...

:laff: and 8,000-9,000 feet is not an option for you either!
 
PA usually comes up when doing take-off and landing data charts so setting field elevation or looking at the transponder may not be an option. I hate formulas so I think what would my altimeter say if 29.92 is dialed in at field elevation. Remember 1 inch of Hg per 1000 ft. Soo, if altimeter setting is .1 inch from 29.92, the diference is 100'. Which way? remember that when you increase the altimeter setting in the window, the indicated altitude gets bigger, when you decrease it, the indicated altimeter gets lower. So, if current altimeter setting is less than 29.92, you have to increase the altimeter setting to get to 29.92, so PA is higher than field elevation. If current altimeter setting is above 29.92, you decrease the number in the window so the PA is less field elevation. Yes I'm and Aero major and teach several course for the USAF but as my first roomate flying F-4s told me: When it is night, you are in the weather, or someone is shooting at you, everybody becomes a Physical Education Major! I have verified that many times over the the last 30+ years. Keep it simple.
 
If your using pressure altitude to calculate field elevation it will maybe have a 20' factor in ground roll.

If your takeoff calculations require you to be that accurate regarding performance, your probably going to get yourself killed anyway.

Just sayin'.
 
Douglas said:
If you are already there, you can just set your altimeter to 29.92.

or formula time

29.92 - current barometric pressure, x 1000 plus elevation = PA
Click to expand...

I just wanted to addd, put it in this format even when the pressure is greater than 29.92. It just gives you a negative number, which can be subtracted.

29.92
- 30.12
= - .20
*1000
= -200
- elevation (1253)
PA = 1053

Now you will never get confused by PA going up versus down.
 
shdw said:
I just wanted to addd, put it in this format even when the pressure is greater than 29.92. It just gives you a negative number, which can be subtracted.

29.92
- 30.12
= - .20
*1000
= -200
+ elevation (1253)
PA = 1053

Now you will never get confused by PA going up versus down.
Click to expand...

Say wha?

Think you had a typo into there.
 
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