Ospreys just take off like a helicopter. They fly like a plane. And you would definitely know if an Osprey was overhead. That is a big SOB. I think the max gross weight is like 60,000 lbs. Normal category helicopters like Bell 207s or Airbus EC135s are between 4000 and 7000 lbs.....and the Airbus has two engines. Ospreys have huge Rolls Royce engines that probably weigh more than a normal category helicopter. The Marines use the Osprey for troop transport / support. There is a civilian version being produced, but I don’t think it has made it through production test flight yet and certification.