The XCOR EZ-Rocket is a test platform for the XCOR rocket propulsion system. The plane is a modified Rutan Long-EZ, with the propeller replaced by first one, then a pair of pressure-fed regeneratively cooled liquid-fuelled rocket engines and an underslung rocket-fuel tank. The engines are restartable in flight, and are contained within Kevlar armour shielding for safety reasons. The EZ-Rocket is registered as an experimental aircraft.
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First flight took place on July 21, 2001, flown by test pilot Dick Rutan.
On a typical flight, the EZ-Rocket takes off on rockets, gains altitude for a minute or so, then switches off the rockets and glides to a 'dead stick' landing.
The vehicle actually flies better during 'dead stick'/glide landings than a Long-EZ due to lack of drag from a stationary pusher prop — the vehicle's aerodynamics are 'cleaner', in spite of its belly tank. It is also lighter due to the lack of a piston engine (the rocket propulsion system is significantly lighter), so enjoys significantly lower wing loading than a stock Long-EZ.
XCOR registered it as a conventional aircraft, rather than a suborbital. The vehicle does not reach the 100 km Kármán line altitude.
The Rocket Racing League aircraft currently in development, the Mark-III X-racer is a design descendant of the EZ-Rocket aircraft. Although XCOR is not the developer of the rocket engine for the Mark-III, XCOR did develop the rocket engine for the Mark-I X-Racer, the first of the X-Racers to use use a single rocket engine on a Velocity SE basic airframe, and the first X-Racer to utilize kerosene instead of isopropyl alcohol fuel. XCOR used both design and operational experience from the EZ-Rocket in the Mark-I rocket aircraft design.