On February 14, last week, an Indian Air Force [IAF] Embraer aircraft landed in Portugal. Since then, it has stayed there.
The Embraer ERJ-135BJ Legacy 600 belongs to the IAF's Air Headquarters Communication Squadron [AHQCS], nicknamed Pegasus. The Squadron's primary task is providing air transportation service to VVIPs. In it's myriad fleet of fixed & rotary wing aircraft, are these Brazilian-origin aircraft, that it's been flying since 2005. In fact, this airframe, christened Meghdoot & sporting Registration No. K3601, was the first aircraft to have reached India.
In Portugal, it touched down in Lisbon, at the Alverca Airport, a Military installation. There has been no Governmental confirmation of this journey. Any official Indian VVIP travel to that country too can be discounted, given that the aircraft has been parked there for a week.
In all probability, it's visiting Embraer's subsidiary, OGMA - Indústria Aeronáutica de Portugal S.A., based there. Imparting it with technological capability upgrades could be the reason for making the journey. In India, the Mumbai-based Air Works India Engg. Pvt. Ltd. is the OEM's Authorised Service Facility [ASF] for executing scheduled MRO of the IAF's ERJ-135. Thus, this aircraft shouldn't normally be in Portugal for anything routine.
No information of this upgrade programme available in the public domain. That said, for an aircraft in service for the past 17 years, sub-systems that could get a "makeover" could include it's Electronic Warfare Suite, including ECCM systems, Self-Protection & Jamming [SPJ] equipment, Missile Approach Warning System [MAWS] & SATCOMS, among others.
The aircraft, en-route to Portugal, had a layover in Greece, landing at it's Eleftherios Venizelos Airport, in Athens, the day before. Intrepid, veteran Aircraft Spotter Savvas Garozis snapped these pictures of the Meghdoot there.
The AHQCS, in 2020, took custody of the Indian equivalent of the American "Air Force One", a custom kitted B777-300ER aircraft, for ferrying India's Top 3.
Outside of Russian & American birds, Embraer platforms have found approving acceptance amongst Indian end-user. Besides 4 Nos. of ERJ-135 BJ, India's first operational Airborne Early Warning & Control Systems [AEW&CS], Netra, it's designer DRDO based on the ERJ-145, of which 3 fly, with a proposal to build 6 more.
A curious journey, with many "known unknowns", the K3601 has made.
Godspeed