Hiller X-18
Hiller Aircraft Company · United States · first flew 1959 · transport aircraft
The Hiller X-18 was the United States' first tilt-wing aircraft capable of transitioning between vertical and horizontal flight, serving as a technology demonstrator for the tilt-wing VTOL concept that would later influence the LTV XC-142 and other designs. It used a modified cargo aircraft fuselage with a tilting wing mounting two large turboprop engines.
Recognition (WEFT)
| W — Wings | High-mounted, straight |
|---|---|
| E — Engines | 2 × turboprop, wing-mounted |
| F — Fuselage | Chase-Fairchild C-122 fuselage with articulating wing pivot mechanism |
| T — Tail | Conventional |
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Spot it by:
- First US tilt-wing VTOL transport research aircraft
- Large tilting wing with two turboprop engines that rotate for vertical takeoff
- Chase-Fairchild C-122 fuselage with articulating wing pivot mechanism
A large, slab-sided transport fuselage fitted with a broad straight wing that can tilt to near-vertical, carrying two large counter-rotating turboprop engines; the wing pivot mechanism and military transport fuselage combination is unique.
Specifications
- The Hiller X-18 has a length of 19.2 m (63 ft).
- It has a wingspan of 14.6 m (48 ft).
- Its maximum speed is 407 km/h (253 mph).
- Typical crew: 2.
Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.
History
Contracted by the US Navy in 1957 and first flown in 1959, the X-18 used the fuselage of a Chase YC-122 cargo aircraft mated with a new wing that could tilt from horizontal to near-vertical. The aircraft made 20 flights but suffered from single-engine safety concerns and a limited flight envelope. It was retired in 1961 after a flight-control malfunction during testing, without achieving full vertical flight transition.
Variants
A single prototype was built; the programme informed later, more successful tilt-wing designs.
Where you'll see it
Flown exclusively as a US Navy research aircraft; retired in 1961 without entering service.
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