But compact sedans, "that is a huge segment," Schwarzenbauer said. The car would be another step in Mini's effort to move part of its lineup from subcompact to compact.
The redesigned Clubman wagon that went on sale in January grew about 12 inches in length and 4.6 inches in width and is Mini's first foray into the compact segment.
Schwarzenbauer said a decision on the fifth volume, or "superhero," car will be made this year, but he declined to give a firm timetable. A small pickup is off the table, he said.
The four volume cars are the three- and four-door Cooper Hardtop, the redesigned Clubman wagon and the Countryman.
The redesigned Countryman is expected to debut this year and go on sale in the United States in 2017. It will not grow substantially in size, just a few inches like the redesigned hardtops and convertible, Schwarzenbauer said. "People are happy with it."
It wasn't so with the previous-generation Clubman, he said: "We got a lot of feedback saying, "I like the design and the concept, but give me more room and four doors so I can get into the back seats more easily.'"
Mini will launch a plug-in hybrid in the next two years, he said. Schwarzenbauer would not say which car would get the plug-in hybrid variant, but added that "we have the technology available."
An electric car is also in the planning stage, but much depends on progress in battery technology, he said. "Mini is the urban brand," he added. "Long term, we will see a lot of electric mobility in the urban environment. Mini definitely needs one."
Schwarzenbauer said he does not expect a significant jump in sales of the 2016 convertible that was launched here. "We have seen in the last 10 years that the convertible segment worldwide is very stable. If you want to grow, you have to win market share."
"It will grow because this car is so much better, but we do not expect big growth," he said.
The redesigned convertible is 4.5 inches longer, 1.7 inches wider and 0.8 inches taller than the outgoing version. Powertrain options are two BMW engines: a 1.5-liter three-cylinder turbo with 134 hp and a 2.0-liter four-cylinder turbo with 189 hp. A high-performance John Cooper Works model will get a turbo four-cylinder engine with 228 hp. The engines can be mated to a six-speed automatic or six-speed manual transmission.
The convertible is the latest Mini to benefit from the use of BMW engines and transmissions. "Compared to smaller compact cars from manufacturers," BMW technology elevates Mini into a more premium segment, Schwarzenbauer said.
The 2016 Cooper is $250 more than the outgoing model with a base price of $26,800 and goes on sale in March. The high-performance John Cooper Works debuts in April and has a base price of $36,450. Both prices include shipping.