In the streets of New York, few things give you away as a tourist as obviously as tilting your head to take in the city's upper limits. But when the red, yellow, and blue helicopter appeared in the skies over Manhattan's southern tip, even the most jaded of native urbanites could be excused for risking a stiff neck.
With the sun setting on a gorgeous evening, the chopper pulled a barrel roll, turning entirely upside down over the Statue of Liberty. It executed a perfect loop near Battery Park. Those moves looked tame when it did a backflip and spun on its axis as it shed precious height, recovering just a few hundred feet above the Hudson River. The aircraft in question wasn't a news helicopter gone rogue or some experimental autonomous rig gone awry. Rather, it was running what its sponsor, Red Bull, described as a practice session for this Memorial Day weekend's Bethpage Air Show on Long Island.
The performance was as head-scratching as it was stomach-churning, because helicopters aren't built for aerobatics the way small planes are. To make this show happen, Red Bull needed an elite pilot—and a special kind of flying machine. You might even call it unhinged.
The Red Bull Aerobatic Helicopter is an MBB BO-105, a multipurpose light twin-engine German model introduced in 1970 and known for a "hingeless" rotor design that gives it high maneuverability, fast climbing performance, and resistance to rollovers when hovering near the ground. The rotor head, to which the blades are attached, is milled from a solid block of titanium rather than multiple components, skipping the hinges that typically allow the blades to bounce up and down to absorb aerodynamic forces. Instead, the little helo's blades are designed to be more flexible. This design is simpler and thus more reliable, but the important bit here is that this setup allows for more precise flying. The lack of up and down blade movement at the rotor head limits the "play" in the control stick, giving the pilot more granular control of the helicopter.
Compared with conventional whirlybirds, this sort is more expensive (because the solid rotor head is hard to build), and its flight isn't as smooth for passengers in turbulent air. But Red Bull pilot Aaron Fitzgerald, who executed the maneuvers above and around the Statue of Liberty, isn't much for comfort (or cost). "The unique rotor system is what allows us to do what we do," says Fitzgerald, who served as a paratrooper in the US Army's 82nd Airborne Division before joining Red Bull.
Flying a helicopter upside down is rather different from flipping over an aerobatic airplane, whose wings can generate lift whichever way they're pointed. Helicopters can only can only send lift-generating air in one direction. Turn it over, and it's going to accelerate you toward the ground. So, Fitzgerald essentially "tosses" the helicopter into an inverted position and exploits the rotor's precision to recover smoothly on the other side. "Because the rotor system is always developing thrust, we use that tendency to power through the maneuver," he says. The rotor's downwash helps the helicopter "float" out of an otherwise perilous dive, while its minimal rotor movement allows Fitzgerald to set up those recoveries via precision control inputs.
The energy drink maker's Flying Bulls team hasn't modified or reinforced its BO-105 to handle these maneuvers. The outlandish dives and loops are just rarely used by the average operator—though military customers appreciate the ability to pull dramatic maneuvers while flying low and landing and taking off quickly in combat environments. "We like to say that the helicopter's only limitation is the skill and training of the pilot," Fitzgerald says.
His own training, from noted aerobatic pilots Rainer Wilke and Blacky Schwarz early in his career, has indeed paid off. Fans who missed the topsy-turvy performance over Manhattan last weekend—or just want more of the same—will have a second chance to see it in action this weekend, along with Red Bull Air Force's skydivers, base-jumpers, and wing-suit fliers. Also on the docket: The US Air Force Thunderbirds. We hear they can go upside-down too.
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