Necessity is the mother of invention, as they say. And I had a unique need: carrying a hang glider from Chattanooga to Toronto on top of my Lotus Evora S. To say that the Evora is not the ideal car for carrying a glider is like saying that an F18 is not the ideal plane for a family flight to Disney World – the Lotus is a tiny, low-slung sports car designed for race tracks and twisting mountain roads.
Could the Lotus carry a hang glider? Many doubted it. But as an ex-mechanic and lifelong engineering buff, I like a technical challenge. Some research turned up a product called the Seasucker roof rack. Most racks are clamped onto the car. Not the Seasucker – it uses vacuum cups to attach itself like a remora fish sticking onto a shark. I was intrigued. But could vacuum cups hold my high-priced glider at highway speed for more than 1,300 kilometres?
I met up with Ryan Aitchison, a professional bike racer and Seasucker rack distributor. Within seconds, he had a Seasucker bike rack vacuumed onto the roof of my Lotus. I tried ripping it off, and failed. This thing was stronger than it looked.
I left Ryan’s shop with a Seasucker paddleboard rack, which uses six vacuum cups to suction itself onto the roof, and a pair of crossbars to support whatever you want to mount – like a cargo box, a surfboard or, in my case, a five-metre-long hang glider.
Carrying hang gliders is a bit of a black art. Gliders are long, and need to be protected from point loads – you don’t just throw on the roof rack and tie them down with twine. Front supports are advised, and it’s a good idea to support the glider along most of its length. Pilots have rigged up all kinds of support systems, including extension ladders, cut-down sewer pipes, and custom-built trusses.
Some competition pilots have carried gliders on rental cars by putting an air mattress on the roof to protect the paint and pad the gliders – and rigging up front supports made from plastic pipe.
I’ve made numerous racks myself over the years. Now I had a plan for a high-tech rig made from aluminum extrusions. The rack would be adjustable to fit any car. All it needed was a roof rack to fasten to. With the Lotus, this was a problem – at least until I learned about the Seasucker.
A week later, the new rack was on my Lotus, attached to the Seasucker crossbars. I’d abricated a pair of front support struts from a set of telescoping tripod legs. The struts connected to the Lotus’s hood with two Seasucker cups. The rack seemed to work well, but I was leery about the vacuum pump’s ability to hang on at high speed (aerodynamic loads increase as the square of velocity.) Just to make sure, I took the Lotus to a race track with the rack on top. At 230 km/h, it didn’t budge.
In Chattanooga, I picked up my new glider and mounted it on the rack. It worked beautifully. You don’t see a glider on top of a car like a Lotus often (pilots tend to drive SUVs, or old beaters that free up funds for more important things like flying trips and new gliders).
The return-trip to Toronto provided a torture test for the new rack and the Seasucker cups. The glider was buffeted by rain, crosswinds and the vortex from passing 18-wheelers. My concerns vanished – the system passed the test with flying colours.
The Seasucker is anything but a gimmick. This is a serious piece of gear that allows you to attach a rack to almost any vehicle. I used it to carry my glider and a pair of mountain bikes on several different vehicles, including a Maserati and my new Toyota Prius.
The Seasucker rack is available in a wide range of configurations, including multisport carrier and minimalist bike racks. The system has a couple of major advantages over traditional, clamp-on roof racks: it can be attached or removed in seconds, and can be transferred from vehicle to vehicle.
But it isn’t a system for the careless or ill-informed. Although each vacuum pump is capable of holding about 100 kilograms, the strength of the bond depends on maintaining a vacuum. As the Seasucker representative taught me, the spots where the pump cups will be attached need to be clean, because dirt will keep the cups from making an airtight seal. To attach the cups, you press a small cylinder that operates an internal vacuum pump. If the cups begin to lose suction, there is a warning line on the pump cylinder.
After using the rack for three months, I learned to trust the cups. Although I checked the pumps every day, they never lost vacuum. And the Seasucker rack proved incredibly versatile, popping on or off any car in seconds. The only limitation was convertibles – the suction cups don’t work on fabric roofs.
Best of all, my Seasucker-pump support struts are still going strong. The rack is now on my Prius. I’ll be on my way to Chattanooga again soon, with the Seasucker cups holding down my treasured Wills Wing U2. Can a vacuum cup carry a load? You bet.
