It may be that there was no need for helicopter transfers elsewhere - in Ireland he had to visit a small village around 75 miles from Dublin as part of his planned 24 hour programme between meetings at 1000 and 1700. Had he been only visiting Dublin, I suspect road transport alone would have been used, as during his transfer from the Arás to College Green and from the city centre to the airport later. In other parts of his European visit he may have had more time and/or less travel - or there may have been locally based aircraft available from German bases. I don't know for sure - just supposition.
In terms of road vehicles, there were at least two sets involved - the vehicles used in Dublin (apart from the one damaged by the kerb at the Embassy
) were sent on to Paris, while a second set were used in London which were subsequently sent to Poland, in effect leapfrogging the presidential party.
As for resourses - well, the trip to Moneygall involved two Whitehawks and three (should have been four) Chinooks. The US military are not known for cost consciousness!
MD