EMBRAER KC-390 (PT-ZNJ)

So many questions! Why is a Brazilin military transport airframe, under development, flying strange patterns around the mid-west (USA) the last few days? And, what is the orange device above the crew cabin?

With warmer weather where they are based they came to the US for colder weather,they actually were doing some icing testing on the aircraft and systems,that is why trips to New York and Chicago.It would be part of the certification process.