Pressurization

WARNING: This application works only with devices equipped with barometer (iPhone 6, 6+, 7, 7+, SE).

Pressurisation is used to create a safe environment on board of aircraft flying at high altitudes (generally above 13,000 feet). Compressed air is pumped into the cabin trough an environmental control system.

This application can measure the differential pressure and relative altitude of a pressurized aircraft cabin.

There are 4 cockpit design available:
• PIPER: preferred for turboprop aircrafts (max 5.5 ΔP)
• CITATION: based on the notorious biz jet (max 8.9 ΔP)
• BOEING: preferred for jet airliners (max 9.1 ΔP)
• AIRBUS: preferred for jet airliners (max 8.6 ΔP)

The cabin altitude gauge (CABIN ALT), displays the relative altitude inside the cabin of the aircraft in thousand feet.

The differential pressure gauge (DIFF PRESS or ΔP) displays the difference between the air pressure inside and outside the aircraft in PSI. The higher the differential pressure, the lower the cabin altitude is at a same flying altitude.

Example: a plane flying at an altitude of 25,000 feet with a cabin differential pressure of 5 PSI will provide a cabin altitude of 9,100 feet while a plane flying at the same altitude but with a cabin differential pressure of 6 PSI will provide a more comfortable cabin altitude of 6,700 feet.

The variometer gauge (CABIN CLIMB) indicates how quickly the cabin is climbing or descending in feet per minute.

The ground speed is displayed in Knots. The Mach indicator is based on estimated IAS and altitude.

A "direct readings" page allows to read the sensors' raw data.

LIMITATION:
• This application works only on devices with barometer.
• The GPS has to be active. If you are in airplane mode, initially start the Apple maps app to activate the GPS.
• A good GPS signal is necessary for the app the work correctly. Place your iPhone in a position where you get a clear view of the sky, preferably close to a window. It can take up to few minutes minutes to receive a good signal.