The Rocket Racing League (RRL), a private venture hoping to create what some are calling "NASCAR in the sky", announced today that they will hold several demonstration races later this year to highlight their rocket planes and planned air race series.  Announced several years ago, the Rocket Racing League was formed by the X-Prize principals soon after SpaceShipOne captured the X-Prize for the first successful privately-funded sub-orbital spaceship. The backers of the RRL hope to keep the strong public interest in space and rockets generated with SpaceShipOne going strong by putting rockets on a small aircraft and racing them around a virtual "track" in the sky.

I've been following this venture since it was first announced back in 2005, and I'm still not convinced that this will be a big hit with the general public. While I applaud the X-Prize folks for wanting to keep the SpaceShipOne momentum going, and for promoting advancements in privately-funded rocket technology, I just can't see this becoming anything more than a novelty flying display at air shows. (If you really want to see a successful air race that has caught on with the general public, check out the Red Bull Air Race series, which has drawn hundreds of thousand of spectators at various cities throughout the world since 2003.) First, the proposed rocket planes only have a very short duration of powered flight, less than 10 minutes. (While rocket engines can provide spectacular takeoff and climb performance, they aren't exactly fuel efficient.)  The racing rocket planes will takeoff, fly for a few minutes on rocket power, cut the rocket engine to glide for a little bit, then reignite the rocket engine for some more high speed flight, finally gliding to a landing when their fuel is exhausted. Not exactly a nonstop display of raw power for several hours like a NASCAR car race. Second, the rocket planes won't be racing at the same time, but will start at staggered times and basically be racing against a clock.  And finally, since they will racing on an "virtual" course in the sky, the only way spectators will really know how they are faring is by looking at giant video screens which use computer graphics to show where the planes are on the course. I think trying to make sense of an air race by looking back and forth between a small plane rocketing through the sky and an outdoor video screen is going to be confusing at best.

Then there is the safety issue. Let's face it, many folks go to NASCAR races to see the crashes. Fortunately, the cars, race tracks and driver equipment have seen such recent advances in safety that even after a spectacular crash the driver can walk away. If fans have those same expectations (spectacular, but survivable, crashes - no harm done) at an RRL event, they may be in for a rude surprise. Even though the RRL is talking about using some of the NASCAR safety technology in their planes, like strengthened cockpits, I don't think much of it is applicable to a small, light aircraft that is traveling much faster than a race car. A crash at 300+ mph (projected flying speeds for the rocket planes) has a lot more energy to dissipate than a race car crash at 200 mph. If there is a major problem (loss of control authority, structural failure, massive engine failure, etc.) in one of these rocket planes, there aren't many options for survival. Unless they have an ejection seat (too heavy and too costly for these aircraft) or a whole airframe parachute recovery system, the pilot's chances of survival would not be as good as a NASCAR driver. The other safety issue that I'm not clear on is the use of Liquid Oxygen (LOX) as one part of the combustible ingredients used to fuel the rockets. The way I understand it, each race will have multiple laps, but since the rocket engines have such short durations, they will have to be refueled several times over the course of the race. Just like in a NASCAR race, time during a pit stop counts against your overall time, so the ground crews will be under pressure to refuel the rocket engines as quickly as possible. I remember back when the U.S. military decided to eliminate LOX in tactical aircraft as the primary crew breathing method for fighter pilots due to safety and handling issues. (Today airplanes such as the F/A-18 use an On board Oxygen Generating Systems - OBOGS- to provide breathing air. If you want to see some of the safety issues with LOX, check out this old military training film.) So unless the RRL devises a technology to quick-fuel a rocket engine with LOX that provides redundant levels of safety, rushing to get volatile LOX into a race plane as quickly as possible may not be the smartest thing to do.

So, while I commend the RRL for trying to get the general public interested in aviation, space and rocket technology, I don't think rocket powered aircraft will be anything more than a niche market at air shows. A relatively light aircraft powered by a rocket engine could provide a spectacular, if very brief, flight demonstration that would captivate an air show crowd, but I just don't see the racing aspect catching on with the average Joe Six-Pack NASCAR fan.