Image courtesy of the U.S. Patent and Trademark Office
Boeing is now the proud owner of a tiltrotor aircraft patent and convertible compounded rotorcraft patent.
In its Oct. 25 issue, the U.S. Patent and Trademark Office's Official Gazette listed Boeing as a 17-time patent recipient. These newly issued patents include chromium-free conversion coating, new systems for paneling and a new fixed-wing steering method for taxiing, among others. Patent applications generally take a few years to become officially issued — Boeing’s taxiing method lists a 2010 file date.
But among the patents for aircraft aspects, Boeing's two patents for rotorcraft designs were filed in 2014.
Boeing’s tiltrotor design differs from existing tiltrotors by virtue of a low-wing configuration. As outlined in the patent, high-wing configurations add weight and complexity, as well as inconveniences in fueling and maintenance. A low-wing design would eradicate the need for structural reinforcements that prevent the wings from crushing the fuselage during a crash. The lack of structural reinforcements means more space on the aircraft, be it for mid-cabin exit doors without the need for escape slides and easier refueling.
Boeing’s patent also covers the use of more than two engines. This way, the engines can be smaller, but still meet functional needs. Some existing tiltrotor designs have the engines attached to the tiltrotor. Boeing’s engines, in some embodiments, could be fixed to the wings. There are many different configurations outlined in the patent, leaving room for designs with different engine configurations.
Boeing’s compound aircraft patent outlines a couple different embodiments. One configuration could be a fixed-wing aircraft with a removable rotor. Another configuration could be a fixed-wing aircraft that is small enough to be paired with, and carried by, a rotorcraft. The outlined docking mechanisms would also have the ability to release the aircraft. Furthering the idea of two separate aircraft flying together, the patent outlines a configuration in which a fixed-wing aircraft could be attached to a rotorcraft, with the capability to un-attach, to augment speed and lift.
The patents do not have any mentions of goals or timelines, but they outline various configurations and embodiments of Boeing’s methods and designs leaving many possibilities. A future Boeing tiltrotor could carry at least 100 passengers as a commercial transport vehicle, the patent says, while it could also have military applications. The compound aircraft patent is accompanied by a range of illustrations, displaying different configurations including docking, cargo transport and unmanned aircraft system support.