Rocket Racing League Unveils New Flying Hot Rod

Two rocket-powered competitive aircraft took off together Saturday to showcase the Rocket Racing League's new aerial muscle machine as it kicks off a 2010 World Exhibition Tour.

The league unveiled its new Mark III X-racer rocket plane in the high-flying event, which was part of the QuikTrip Air & Rocket Racing Show in Tulsa, Okla. Beginning this year and stretching into 2011, the Rocket Racing League will conduct a series of demonstrations at air shows across the country.

These exhibitions are aimed at building up the league?s fan base, in addition to perfecting operations and technologies before the league?s official launch in 2012, said Ramy Weitz, CEO of the Rocket Racing League, who participated in a live webcast of the April 24 demo flights in Tulsa.

The Rocket Racing League was founded in 2005 by X Prize founder Peter Diamandis, and Granger Whitelaw, a two-time Indianapolis 500 champion team member.

The league features rocket-powered aircraft, called X-racers, flown by Top Gun and other acrobatic and military pilots in closed-circuit and drag-style races that pit two to 10 racers against each other in a virtual, custom-designed 3-D raceway in the sky.

New rocket plane's debut

The current X-racer models are using a Velocity airframe and a single-thrust liquid oxygen and ethanol rocket engine developed by the Texas-based Armadillo Aerospace.

Unlike a regular jet engine that burns oxygen from the atmosphere as its oxidizer, X-racers carry their own oxidizer in the form of liquid oxygen. The current Mark II and Mark III X-racer designs fly at speeds of over 200 mph (322 kph).

The X-racer engines are filled with 500 pounds of liquid oxygen and 500 pounds of ethanol, before being pressurized with helium to 320 psi (pound-force per square inch). When ignited, the engine produces a 15-foot flame and about 2,500 pounds of thrust that gives the vehicle liftoff within 4 seconds of ignition.

The entire fuelling process takes approximately one hour. In Tulsa, the league demonstrated its ability to have a very small crew fuel both X-racers simultaneously.

Virtual rocket racecourse

Before the X-racers took to the sky in Oklahoma, a Cessna 420 aircraft demonstrated the new technology that makes possible the Rocket Racing League?s 3-D virtual racecourse.

A cockpit-based Augmented Reality System projects the racecourse onto 3-D helmet displays that enable the pilots to see the race track right on their visors. The exhibition in Tulsa was the first time that the helmets and racecourse technology were exhibited to the public.

Spectators at the event could view the superimposed augmented reality on large projection screens, and could follow as the Cessna manoeuvred through virtual gates to complete the course.

In Saturday?s demonstration, Rocket Racing League Chief test pilot Len Fox flew the ?T-1? X-racer, while test pilot Dave Morss flew the new Mark III ?T-2? plane.

In their first flight, both planes lined up at the end of the runway, with Fox taking off first, and Morss following 13 seconds after.

Fire and glide

Since the rocket planes have no throttle, the pilots turn their engines on and off throughout the flight in a series of thrusts and glides.

The planes carry enough fuel for a total of two minutes of thrust. So, once real racing begins, the winning pilot will likely be the one who most effectively manages the plane?s energy under such constraints, Diamandis said.

In Tulsa, the league?s first demonstration flight went off without a hitch. In their second planned flight, they prepared to fly the X-racers in closer proximity to one another, but an anomaly forced both planes to land shortly after they took off.

?The engines that these X-racers use are computerized,? said Diane Murphy, a public relations official with the Rocket Racing League.

?If the computer detects that there?s any sort of anomaly, or anything that could potentially be not right, it shuts down the engine,? Murphy told SPACE.com ?In today?s second flight, when one of the pilots went to go full throttle, the computer had shut the engine down.?

Both pilots were able to glide back to the runway and land safely. Moving forward, engineers will perform more tests and analysis on the X-racers in order to understand what caused the anomaly.

Despite the shorter second flight, Weitz and Murphy consider the Tulsa demonstration a success. The league was able to showcase the virtual raceway technology and fly two rocket-powered X-racers together, all before an enthusiastic crowd of over 30,000 fans.

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