Swiss tuning company Rinspeed, inspired by Bond's Esprit, tackled this intriguing challenge and displayed its sQuba concept car earlier this year. It's a fascinating vehicle, but a close look at the finished project reveals just how difficult it is to create a vehicle adept both on pavement and underwater.
Naturally, Rinspeed started with a white Lotus--in this case, the Elise. The Elise's gasoline engine was replaced with three electric motors and a lithium-ion battery pack. On dry ground, a 54-kilowatt electric motor drives the car, while while two smaller electric motors power small propellers underwater. Two front fender-mounted blow jets pivot to provide directional control. Other technological pieces of gingerbread include an onboard air supply, a salt-water-resistant interior, and a laser sensor to allow driver-less operation (think KITT of Knight Rider fame).
First, the good news--it all works. The sQuba can drive autonomously as promised, but far more importantly it fulfills the promise of a car that can operate under the waves. Drive it into the water, and it floats and operates as a boat. Open the doors to flood the interior, hook up the breathing apparatus, and the sQuba is happy to cruise underwater. When you're ready to return to dry ground, simply drive up a boat ramp or the nearest firm beach. It's fantastic and magical; a dream come to life.
Like many dreams come true, though, the reality isn't quite as attractive as the fantasy. The sQuba is a fantastic engineering achievement, but the compromises necessary to make the same vehicle functional on land and water make it less than ideal in either medium.
As a car, the sQuba has little of the Elise's appeal. The production Elise is a sports car in the classic Lotus tradition; light and incredibly precise. The sQuba is less powerful and, more damning, much heavier. Adding weight to the Elise is like relegating Brad Pitt to a permanent career in radio--you're removing its greatest strength. With a top speed of 75 mph, any sQuba-driving would-be James Bond would be quickly captured. "I suppose I might out-accelerate the odd milk float," Tiff Needell dryly commented in 5th Gear's review.
The sQuba's aquatic capabilities are real but limited. It tops out at just under 4 mph (3.2 knots) on the surface and just less than 2 mph (1.6 knots) underwater. It's also not going to take you down to the Mariana Trench--the sQuba's maximum dive depth is just over 33 feet. It's still a remarkable machine, of course, and trundling along 30 feet below the surface at 2 mph still sounds like great fun. But I doubt any hard-core scuba diver would see the sQuba as anything other than an entertaining novelty.
And, yes, it has an open cockpit. This makes perfect sense, of course--a sealed car would be much too buoyant to go underwater without two more tons of weight, and it's much easier to escape an open-topped car. Still, it's a little less refined than Bond's Esprit. Had he been driving a sQuba, Bond's natty attire would be streaming with smelly sea-water and seaweed. Witty bon mots are also a little more difficult when speaking underwater through a breathing regulator. Instead of murmuring "I think it's time we said goodbye to an unwanted guest," Roger Moore would instead make inarticulate gurgling noises while gesticulating madly.
This is all nitpicking, of course. I referred to the sQuba a novelty above, and of course that's exactly what it is. It's a concept car, the first of its kind (to my knowledge) to successfully drive on land and swim underwater. It might not be a great sports car or underwater exploration tool, but if I owned my own tropical island with its own road system, I'd be waiting for the chance to write Rinspeed a check for a production version.
Squba4Even beyond its appeal to the casual rich, the point of the sQuba is simply that it's deeply cool. In my continuing effort to expose my three-year-old daughter to something other than the Disney princesses, I showed her the two sQuba videos below. She watched in rapt silence as she watched the car go underwater and surface again. When it ended, she wanted to see it again. And again. And again. She's pretty resourceful, so I hid my car keys just to be safe--I didn't want my car to somehow wind up at the bottom of Lake Washington.
The first video is the entertainingly cheesy official Rinspeed production, which shows off the autonomous driving feature and shows some formalwear getting ruined. The second video is the 5th Gear review in which a highly nervous Tiff Needell goes underwater in the sQuba.
Now we can drive in underwater 
