The two largest airlines in Japan — All Nippon Airways and Japan Airlines — grounded their fleets of Boeing 787 Dreamliners on Wednesday, after an ANA Dreamliner was forced to make an emergency landing due to technical problems. It's just the latest in a string of recent mishaps for the Dreamliner, exacerbating a public-relations headache for Boeing and possibly indicating that the aircraft's problems may be more serious than first believed.

The ANA Dreamliner was forced to land about midway through a 90-minute domestic flight, after a "burning-like smell" began to emanate from the cockpit. The situation was dangerous enough that the plane's evacuation slides were deployed once it reached the tarmac. According to ANA, the plane's lithium-ion battery was blackened — "as though it had been burnt" — and was leaking fluid. Last week, another Dreamliner battery caught fire, while two planes experienced fuel leaks, one a cracked cockpit window, and another a braking system problem.

Japanese officials are investigating the latest incident, with Transportation Minister Akihiro Ota saying, "I see this as a serious incident which could have led to a serious accident." U.S. authorities are also on the case; the Federal Aviation Administration last week ordered a review of the Dreamliner's design.

Airline executives maintain that the Dreamliner is safe, describing the aircraft's recent setbacks as "teething problems" common to all new airplane designs. Analysts say it's unlikely that airlines will cancel their orders of the plane, which carry a $200 million price tag. "I would be amazed if any airlines were sitting there today wondering about their orders," Paul Sherian, an industry consultant, told CNN. "I can't see that happening."

However, in a worst-case scenario, the Dreamliner's mounting problems could point to a serious flaw that would require a complete overhaul of the design. Under scrutiny are the plane's electrical system, which is meant to handle a multitude of operations, and the lithium-ion battery, which is lighter and more energy-efficient than traditional batteries. An overhaul would amount to a punishing setback for Boeing, which delayed the Dreamliner's debut by several years to iron out glitches. 

And even if the Dreamliner is safe, Boeing may lose the confidence of passengers if mishaps continue. The company's stock took a dive on Wednesday, and it has received a stream of bad press. (One headline: "Boeing's 787: Will This Plane Kill You?") The company has invested a lot of money in the Dreamliner, and hopes to sell 5,000 models in the next 20 years. But industry insiders say Boeing's European rival, Airbus, may already be positioning itself to take advantage of the Dreamliner's woes. Airbus' new model, the A350, is expected to debut in 2014.