Zeppelins, dirigibles, blimps, airships, and balloons … there is something amazing about these gigantic aircraft that serenely float across the sky. These enormous bags of gas seem to defy gravity, or at the very least, maybe just escape gravity’s notice for a short little jaunt above a sports stadium.
Someone had the genius to wonder, “Why just fly over the arenas? Let’s take them indoors as well!”
That’s where I come in. For the past decade and a half, I have had the pleasure to captain the Airship Team for the Pittsburgh Penguins, an NHL hockey team. I fly the airships, and have trained other pilots to do so as well. It takes a team of pilots and ground crew to make everything happen perfectly when timing must be precise and failure is not an option.
What are the airships and how do they work? RC stadium airships come in all sizes and shapes, From roughly 8 feet long to more than 30 feet, their size varies based on the venue, the conditions you will be flying (indoors versus outdoors), and what you are going to be carrying (banners, cameras, prize-drop mechanisms, etc.).
They can be electric or gas powered, and a well-balanced aircraft can stay aloft for more than an hour under the right conditions.
The Envelope
Most airships have similar components, starting with the envelope or bag. The envelope is what gives an airship its lift. Filled with helium and lightly pressurized for a firm shape, the envelope is a sealed bag of lighter-than-air gas. The bag must be large enough to contain enough volume to lift everything: the envelope, the tail fins, tail motor, gondola, main motors, RC components, batteries or gas, and anything extra you might want to carry. The volume must also be balanced, so that the aircraft flies level and not nose up or nose down.
The most common shape is a sideways teardrop as it stays aerodynamically neutral. You don’t want it to climb or descend unintentionally when you go forward. Envelopes are made from plastic or vinyl, and are not much more durable than your average lawn or construction-grade trash bag.
Filling the airships requires a lot of helium! Smaller aircraft use less than 300 cubic feet, or roughly one five-foot cylinder, while our larger ones gobble up four or more cylinders. At an average of $150 per cylinder for a day of flying, it adds up quickly. My crew and I currently fly two aircraft per game, using six to seven cylinders to fill both, although we try to hangar them as fully inflated as possible between games to conserve helium and time.
Filling an aircraft with helium is easy. After spreading it out on a ground cloth, we tether the front and rear to ground weights. We hook up a hose to the fill port on the ship and then gently crack open the helium cylinder, creating a large pocket of helium in the envelope by the fill port.
We gradually increase the flow, because too fast of a flow can rip the envelope with the unregulated air. When the envelope begins lifting off the ground, the gondola, tail fins, batteries, and a few weights are added, and the airship drops back to the ground.
We continue filling until the aircraft starts to take off again. This is what we call positive buoyancy, but it looks pretty saggy and underinflated. If we are breaking in a new team member, this is when we usually tell him or her to start blowing in the tube to make the envelope tight, which can provide hours of entertainment and usually ends with someone unconscious on the floor.
Normally we hook up a vacuum cleaner, switch it from “suck” to “blow,” and inflate the aircraft to the firmness of a pool toy, but not tight enough to pop a seam. This mixture of helium and air is what we fly with when we have an aircraft with unneeded buoyancy. If we need more buoyancy, we simply add more helium and less air.
The Gondola
The gondola is the heart of the airship. It contains a mixture of RC model parts. We have several gondolas from different manufacturers. Molded plastic, hand-laid carbon fiber, flower pots from Home Depot—anything goes if it works.
The most common setup is three motors: one in the tail that can go forward or reverse, and two main drive motors mounted on the gondola that can rotate together more than 180° using a large servo, from up and slightly back to straight down. I usually prefer the main engines that have the ability to go into reverse, which requires a set of RC car ESCs.
Because blimps don’t fly fast, there are no elevators or rudders cut into the tail fins. There is insufficient airflow to make them useful. The tail uses a propeller that spins in both directions to swing the tail either way. The blimps will always turn one way better than the other with this setup, but I have an airship with two propellers stacked on top of each other in either direction, which allows it to turn fairly well.
For control, one channel handles the tail, left or right. One channel controls the main motors, forward and reverse; and one channel drives the main motor rotation, up and down. We use our transmitters set to Mode 2 on most of our blimps, but the left throttle ratchet actually controls the motor rotation, so we can set an angle on the main motors and lock it in.
The right vertical stick controls the main motors: up for forward, down for reverse. The right horizontal stick is for the tail, moving in the direction you press the stick. You might think we would be using Spektrum DX18 transmitters or something similar, but we could probably fly most airships with the beginner transmitters.
In actual flying conditions, the ability to have servo end point adjustment and telemetry makes setup and flying much easier and more dependable. A good compromise between cost and features are the middle-of-the-road transmitters. Each airship has its own transmitter, and we currently use a Spektrum DX5E, a DX6i, a DX7s, a Futaba 7C, and a Hitec Aurora 9, but we have a 22-year-old practice aircraft still rocking a four-channel 72 MHz Futaba radio from 1990.
I use the Aurora 9 on a giant flying pig for a local grocery store’s events. The flying pig is different than a normal airship. It has five motors, all capable of forward or reverse, two on the gondola, one in the tail, and one in each ear serving as an adjustable canard for attitude control. Depending on the setting, all the motors on the right can go in forward, while all the motors on the left go in reverse, and the tail goes right and left so that the whole thing can spin on a dime or do stunts.
It features internal LED lighting and a prize-drop mechanism. The Aurora 9 is set up similar to a conventional helicopter and the rear sliders actually adjust the main drive motor angle. The flying pig also flies indoors and outside. To quote a wise spider, “That’s some pig.”
What fun is just flying over a crowd of 18,000 screaming fans? How about airdrops? People go absolutely crazy for prizes dropped from an airship high overhead. The drop mechanisms come in different sizes and shapes, capable of firing ping pong balls, dropping hats, or dropping prize envelopes. There is a mechanism for anything you can lift with the aircraft.
What we usually use is a simple drop mechanism that works at the slow speeds at which we fly, dropping a one or two dozen envelopes, one at a time. Using a sailing winch servo that will spin continuously left or right on command, or cutting and modifying a servo, we attach a large loop spring cutoff at one end. Then we punch a hole in the envelope and load the envelopes onto the spring, one envelope per rung until every rung is filled, 12 to 20 four rungs. On most airships, we set this to the left horizontal stick on the transmitter. Left reels the envelopes off one at a time, right reels them back on. If you want to be creative, you can fold the envelopes so they flutter all over the place and excite the fans.
Piloting
One of the most common questions I am asked is “where do you sit in the airship to pilot it?” After swearing people to secrecy and then explaining the complicated process of miniaturization on a biological subject, I usually slip away as quickly as possible in search of some great stadium nachos. We don’t sit in them!
We normally fly from the players’ bench, because it is in the center by the floor, it’s easy to get to, and we can see the entire arena and the airship at all times. Perspective can be deceiving in an arena or stadium, and it is difficult to tell exactly where the airship is in relation to the stands that are at a steep angle, the wall, cables, wires, cameras, and balconies.
Add that you are flying a 20-foot-long, 8-foot-high airship with all the air conditioners or heaters on full blast, doors opening and closing, thermoclines from the ice, as well as body heat from 18,000 people, and flying can be a challenge. That’s why training is important.
Our pilots spend more than 40 hours practicing flying before their first in-game flight, starting with basic position/altitude hold. The airship tends to blow around, which entails constantly rotating the tail to keep its nose into the air current and using the main motors, rocking back and forth together with throttle control, to maintain a solid, midair position.
From there, pilots learn to fly a square box pattern, keeping an equal distance from the Jumbotron and maintaining constant altitude. We include periodic “clock” maneuvers, rotating the airship on its gondola and stopping at 12, 3, 6, and 9 o’clock.
Flying the pattern is the actual game flight path. Over the ice, a mistake is relatively harmless, but over the seats, even empty during practice, blimp parts can get caught or broken on railings, armrests, or balconies.
When pilots have mastered the flight patterns, we add the prize drops. Pilots spend hours dropping fake prize envelopes so that they land in the seats and not out on the ice. Pilots-in-training attend nearly every game and stand with the regular pilots during the flight, while the pilot talks through what he or she is doing.
When it’s time for the first in-game flight, the excitement is overwhelming. The pilots-in-training walk out with me to the players’ box, while the ground crew moves the airship through the Zamboni entrance tunnel and out onto the ice.
With the clock already ticking, a last flight control test is quickly performed, and if given the thumbs-up from the ground crew, the airship is launched and immediately rises with no engine throttle.
Because the airship was in the tunnel where it is warm, and is brought out into the cold air above the ice, it will rise until it finds a temperature zone that allows it to achieve neutral buoyancy, usually roughly 25 feet above the ice. It can set on that temperature layer for a few minutes, but the longer it sets, the cooler it will get, eventually losing buoyancy and sinking again.
Luckily, we aren’t out there long. We fly the airship directly over the crowd, flying slowly and lazily, 10 to 40 feet above their heads.
Working the crowd from the front to the back of the stands, the pilot flies the airship in a zigzag pattern always maintaining altitude and a safety margin, as we go up higher towards the back of the stands or down lower toward the ice.
Periodically, the pilot will drop the prize envelopes to the crowd below. There is no set pattern; we can drop whatever to whomever we’d like. We usually aim for the most excited and animated fans, but when we hit the drop switch, there’s no predicting where they land. I’ve had prize envelopes cross the ice and half of the arena before some lucky person finally catches it. We like it that way, it makes it challenging and fun for us and for the fans.
When the time is right, the pilot brings the airship in for a landing and puts it right into the capable hands of the ground crew, never touching the ice.
Our arena airships have a great safety record throughout the past few decades. The motors and propellers are usually surrounded by an engine shroud, and even with the power to the motors off, the aircraft are so well balanced that they gently float down like a giant soap bubble.
In the event of an emergency landing, the procedure is to make our way over the ice and then hold position until the Zambonis are done. There is a natural turning tendency built into the airships, so if we lose the tail motor we drive the airship back and forth until it is pointing the correct direction—similar to steering the old RC cars that could only travel in a “J.” If we lose one of the main gondola drive motors, we can conservatively finish the flight. It helps to have main motors that can go in reverse for those occasional unique wind current conditions.
Between flights, the crew triple checks the equipment, charges the batteries, and catches the game. After the game, we go to our regular day jobs. On weekends, some head out to the flying fields and smile when someone boasts about his or her 65-inch wingspan aircraft.
The last thing I tell pilots new to flying this type of airship is that flying will never be the same. After you’ve flown a 24 x 8-foot beast that costs more than your first car over a crowd of 18,000 people on national television, it will change how you feel about flying.
The airships we use come from several manufacturers. Mobile Airships in Toronto, Canada, made the Toyota car; Mobili and US Steel built airships for the Pittsburgh Penguins; and E-blimp from California made the flying pig for Bottom Dollar Foods. The price range for these types of blimps start at $4,000 and can go to well beyond $40,000.
For someone interested in a less-expensive blimp, Mobile Airships offers a personal airship through its public website, RC Guys, priced at $346.50. It is 5.5-feet long, and made from polyurethane. The link for the website is listed in the “Sources” section.
