A method of augmenting an existing air data system of an aircraft , the method comprising: attaching a probe (30; 58) to an exterior of the aircraft , wherein the probe (30; 58) comprises a plurality of pressure sensing ports positioned to sense pressure of an oncoming airflow about the aircraft exterior, and wherein the plurality of pressure sensing ports includes a first static pressure port (PS1) and a second static pressure port (PS2) operatively associated with a first electronics channel ; sensing a first static pressure of an oncoming airflow about the exterior of the aircraft at the first static pressure port (PS1) using the first electronics channel of the probe (30; 58); sensing a second static pressure of the oncoming airflow about the exterior of the aircraft at the second static pressure port (PS2) using the first electronics channel of the probe (30; 58); determining a first altitude value based on the sensed first static pressure; and determining a second altitude value based on the sensed second static pressure; outputting the first altitude value and the second altitude value to the existing air data system that supplements or replaces an altitude calculation of the existing air data system , wherein the probe is a multi-function probe, MFP, (30; 58) that is independent of the existing air data system , and wherein the first electronics channel is electrically coupled to the existing air data system for displaying the first altitude value based on the first static pressure sensed at the first static port (PS1) and for displaying the second altitude value based on the second static pressure sensed at the second static pressure port (PS2), wherein the first altitude value and the second altitude value are determined independently of the existing air data system using the first electronics channel , wherein the first electronics channel is integrally attached to the MFP (30; 58). attaching a probe (30; 58) to an exterior of the aircraft , wherein the probe (30; 58) comprises a plurality of pressure sensing ports positioned to sense pressure of an oncoming airflow about the aircraft exterior, and wherein the plurality of pressure sensing ports includes a first static pressure port (PS1) and a second static pressure port (PS2) operatively associated with a first electronics channel ; sensing a first static pressure of an oncoming airflow about the exterior of the aircraft at the first static pressure port (PS1) using the first electronics channel of the probe (30; 58); sensing a second static pressure of the oncoming airflow about the exterior of the aircraft at the second static pressure port (PS2) using the first electronics channel of the probe (30; 58); determining a first altitude value based on the sensed first static pressure; and determining a second altitude value based on the sensed second static pressure; outputting the first altitude value and the second altitude value to the existing air data system that supplements or replaces an altitude calculation of the existing air data system , wherein the probe is a multi-function probe, MFP, (30; 58) that is independent of the existing air data system , and wherein the first electronics channel is electrically coupled to the existing air data system for displaying the first altitude value based on the first static pressure sensed at the first static port (PS1) and for displaying the second altitude value based on the second static pressure sensed at the second static pressure port (PS2), wherein the first altitude value and the second altitude value are determined independently of the existing air data system using the first electronics channel , wherein the first electronics channel is integrally attached to the MFP (30; 58). <EOS>