Have delivered several folk to airports with insturments....and traveled with my own "special gear." (split bamboo Fly-Fishing-Poles)
Airlines have permited carry-ons...in all instances. However, it is important that the "stews" understand the delicate nature and importance of the baggage....there IS plenty of storage inside the cabins ... that are not part of the overhead racks.
Strangest, situation was when we were running late and the airport security insisted on plugging in an "electronic voicer" to assure that it was not a bomb. Arrive, Early.
Eager to hear the story of your trip.