Station Pressure / QFE / QNH /QFF /Static Pressure
We were recently asked if the Kestrel measures pressure in:
1. How do I view Station pressure in my Kestrel?
5. Static Pressure
Here's our answer:
Setting Station Pressure: If you set your reference altitude to 0, the Kestrel will report station pressure, which is also referred to in some countries as QFE (Field Elevation).
If you set your actual altitude in a ref altitude of the baro screen, it will calculate and display the barometric (in American terms) pressure, which is the pressure reduced to sea level (reduce assuming you are above sea level to start) using ISA standard conditions. So the baro screen is now displaying QNH.
More info see: Setting Station Pressure on my Kestrel
QFF is MSLP which is a similar calculation to QNH/NK Baro, except that real conditions on site are used for the correction instead of ISA standard conditions.
The un-asked question that rounds out the discussion would be ‘what is the ref pressure in the alt screen?’. That would allow you to enter QNH from a weather report and use it to see your real altitude, but of course it’s using ISA standard conditions and not actual conditions.
Static Pressure: It depends on what one is calling static pressure. We can do station pressure, not necessarily static pressure. If you consider that the pressure felt at the measuring point is 0 psi to start with, then this is static pressure and the Kestrel cannot determine this. If however the you consider the pressure felt at the measuring point is 14.7 psi to start, then the reference to station pressure and the Kestrel can do this.