Boeinger

What is PTU on Boeing 737? (Power Transfer Unit)

What is G/S on Boeing 737? (Glide Slope)

What is RFLNG on Boeing 737? (Refueling)

What is EXT on Boeing 737? (Extend)

What is IND LTS on Boeing 737? (Indicator Lights)

What is EDIU on Boeing 737? (Engine Data Interface Unit)

What is ESS on Boeing 737? (Essential)

What is ALTN on Boeing 737? (Alternate)

What is UNLK on Boeing 737? (Unlock)

What is ACE on Boeing 737? (Actuator Control Electronics)