6 Reasons You Rarely See Gull Wing Doors Anymore

Source: Mercedes-Benz

Looking for something different in a high-end, modern car? It’s getting harder with each passing year to find a vehicle with a defining characteristic. Whatever happened to that gull wing door design that was so notable that it became an iconic element of some of the world’s greatest vehicles?

Automakers have been playing around with this concept for over 50 years. Some examples came from short-lived startups like DeLorean and Bricklin, although Mercedes-Benz also got into the game early. Now, some of today’s most respected automakers are incorporating this radical style into parts of their lineup. There was the Mercedes-Benz SLS AMG, as well as Tesla, which has also brought in gull wing design in the new Model X, although technically the company calls its engineering “falcon doors” as they articulate a little differently. BMW has done a similar thing with the i8: Although the car’s “butterfly doors” work a little differently, they’re the same kind of divergence from “normal” design that makes the gull wing door so controversial and so loved.

The basic idea, though, is something with an enduring appeal for a certain kind of car aficionado. Gull wing doors are just cool. A lot of us associate them with the classic Mercedes 300SLs of the ’50s or the DeLoreans of the 1980s, the latter of which was immortalized in the Back to the Future film series that caught the imagination of a generation. So now, when we’re decidedly “in the future,” why aren’t more of our cars outfitted with these nifty access setups?

As it turns out, a number of things have led car companies to be very selective in tackling the gull wing design.

1. Gravity rules

Source: Mercedes-Benz
Source: Mercedes-Benz

One of the biggest problems with gull wing design involves fighting the natural gravitational forces that have shaped so much of overall vehicle design. These top-sliding doors have to be designed to lift weight up, and that’s a challenge. For example, the gull wing design on Subaru of America founder Malcolm Bricklin’s design from the 1970s used hydraulics to handle a heavy pair of doors. But after designing the hauling system, engineers have to find a place to put it, and that can end up decreasing the amount of room in the vehicle cabin.

2. Roof problems

Source: DeLorean Motor Company
Source: DeLorean Motor Company

Other designs can cause problems that happen when the infrastructure of the door interacts poorly with the roof of the car. The DeLorean used something called a torsion bar to create tension inside of the cabin. But there was the potential to pull the torsion bar too tight, which could lead to roof warping. So another challenge is to figure out how to exert the right amount of pressure without actually allowing the door operation to destroy other parts of the car!

3. Side collisions and door strength

Source: Mercedes-Benz
Source: Mercedes-Benz

Going back to the idea of door weight, another problem with gull wing design is that it can push engineers to decrease the safety value of the side panels in side collisions. Where designers might want to make doors a lot lighter, doing so can leave drivers and front seat passengers more vulnerable in a crash. So that leaves engineers back at the drawing board figuring out how to heave those strong, heavy doors aloft.

4. Emergency access

Here’s another safety issue that has bedeviled those innovators looking to include gull wing doors in a car design: In a crash, or when the vehicle has rolled or is upside down, there has to be a way to get in — and out. First responders or others have to be able to get into the car to help, and the driver, if he or she is alone, should be able to open the cabin up from the inside. This is another situation where “normal” side door design wins out: Even if the vehicle is on its side, one of the doors can still be opened. On the other hand, if you are in a gull wing car that’s upside down, you’re in trouble, like a turtle pinned in its shell.

Automakers have gone to great lengths to create solutions. For example, for the Mercedes SLS AMG, the company made “explosive bolts” that will actually fire the doors off of the door in some types of emergencies. The problem with these features is that they add cost, so that while it might not be a problem to create a high-end gull wing car, most of the designs aimed at price-conscious customers will opt for the status quo because it’s a lot cheaper.

5. Door sealing

Justin Sullivan Getty Image
Justin Sullivan/Getty Images

There’s nothing as annoying as a leaky roof — and that goes for cars, too. While auto companies have generally been good about finding ways to seal out rain, companies creating gull wing doors have struggled with this, illustrated in some comments from Elon Musk about “learning” about door design while working on the Model X. One of these is the top door’s vulnerability to leaks, as mentioned in this CNBC article about the Model X. It’s generally harder to design a seal, because of where the door edge is positioned on the car.

6. Can you reach it?

MELBOURNE, AUSTRALIA: (FILES) Wayne Gillard polishes up his 1981 DeLorean DMC 12, one of only six in Australia and up for auction at a novelty auction, seen in this 15 July 2004 file photo in Melbourne. John DeLorean, an innovative automaker who left a promising career in Detroit, Michigan to develop the short-lived gull-winged sports cars died 19 March, 2005 in a New Jersey hospital at the age of 80 due to complications of a recent stroke. AFP PHOTO/William WEST (Photo credit should read WILLIAM WEST/AFP/Getty Images)
William West/AFP/Getty Images

Another design problem with gull wing doors involves the driver’s height.

Those with a longer reach may be able to reach up and pull the doors down from their opened positions, but a smaller driver doesn’t have a chance. And while it may look super cool to open these doors and step out of the vehicle, getting back in might not look that cool if the doors aren’t power-equipped. In fact, the whole system can be awkward for taller drivers as well.

All of the above conundrums have combined to suppress a technology that’s over half a century old. While you might love the look and style of the gull wing or falcon door, there’s really not much of a chance that this idea is ever really going to take off or be the “thing of the future” in the mass-market — after all, we almost have self-driving cars now, and their doors still open on the side.

Like classics? It’s always Throwback Thursday somewhere.