Function of primary and secondary RADAR
Primary - Range, bearing, speed
secondary - (transponder response) Altitude, Identity
VS0
VS1
VS0 - Stall landing configuration
VS1 - Stall, clean
VFE
VNO
VNE
VFE -Max speed flaps
VNO - Max normal velocity
VNE - Never exceed
TACAN and how many channels
Tactical air navigation. UHF NAV aid for mil. 252
IESI
Integrated electronic standby instrument
AHRS
Altitude and heading reference system
PITHBLOT
Pressure, Instrument, Temperature, Hysterisis, Blockage, Lag, Orographic, Transonic jump.