“Right, we’re going to have to lean right out now; all three of us,” our instructor Femi Omotosho shouts as the wind catches the sails and we zip across the dock, dangling precariously over the side of the boat. Little do we know that this will be one of the least hairy parts of the day.

We are trying out various sports at Rotherhithe’s Surrey Docks Watersports Centre, based at the side of the kilometre-long Greenland Dock, just across the Thames from Millwall, one of the few places in inner city London you can learn to sail.

Each of us is entrusted with a sheet (or a rope, in layman’s terms) which controls the boat’s foresail or jib while Femi remains firmly in control of the mainsail and rudder.

He assures us he won’t let the dinghy capsize as we zig-zag across the dock, scrambling about to swap sides each time we make a turn and occasionally ending up sitting, undignified and giggling, in a puddle in the bottom of the boat.

Foresail mastered, Femi lets one of us loose on the rudder while the other takes sole charge of the jib and, although we’re not as adept as the dozen or so children zipping across the dock in dinghies, we don’t do too bad a job, as ducks and coots dodge out of our way, until we make a late turn and end up crashing into the wall of the dock.

“We start teaching children from eight-years-old,” Femi says, “and once they’ve had a few lessons they can go out on the water by themselves.”

Fully-qualified instructors are on hand to make sure no one gets into trouble and everyone is fully kitted out with life jackets while children also get helmets.

After lunch kayak instructor Mike Shaw somersaults his boat off the pontoon and into the dock as we shuffle into the water from the slipway. He then proceeds to literally turn cartwheels as we paddle ourselves around in circles, unable to maintain a straight trajectory as we attempt to paddle about the dock.

Mike comes from a family of paddlers and now competes alongside twin brother Chris in freestyle kayak competitions, using white water waves and holes to perform surf and gymnastic-style manoeuvres and tricks.

“It’s easier on white water as you can use it to help flip yourself over but you can do tricks on flat water too,” he explains before flipping his kayak over from end to end, completely dunking himself in the dock.

After we prise ourselves out of the kayaks and dry ourselves off a bit Femi is back to teach us some basic manoeuvres in the rigid inflatable powerboat and we bomb down the dock and turn in a huge arc before he decides we’re ready to take on the Thames.

We wait patiently for the lock keeper to let us out of the dock and cautiously cross the river to the north side before Femi relinquishes control of the boat.

“You want to go fast enough so you plane over the top of the waves,” he explains. “But keep a look out for any debris we might run into; you don’t want that hitting your propeller.

“Keep one hand on the steering wheel and the other hand on the throttle at all times so you can cut the power quickly. Now go on, give it some welly.”

I can feel myself slide back in the seat as we accelerate and tourists in pleasure boats and Thames Clippers look on, presumably perplexed by the mixture of screaming and laughing as we bomb under Tower Bridge, past HMS Belfast and under London Bridge as far as the Tate Modern.

“Are you alright?” Femi yells after he takes over and we whizz down the river towards Greenwich. Gritting our teeth we both nod, concentrating too hard on staying inside the boat to communicate anything further, and occasionally screaming as we bump over some wake created by some of the bigger boats.

“I think we got the whole boat out of the water then,” Femi says gleefully as our knuckles turn white.