They say you’re more likely to die driving to the airport than flying in an airplane.

For commercial flights, that’s true. There were 30,800 fatal car crashes in 2012 and zero commercial airline crashes. A domestic commercial flight hasn’t crashed since 2009.

Most planes that crash are small and private, like the twin-engine Embraer EMB-500 Phenom 100 that crashed into a suburban Maryland home on Monday morning, killing six people in Gaithersburg.

Social video captures the aftermath of a plane crash in Maryland that set homes ablaze Monday. (The Washington Post)

A mother and two children were found dead in their second-floor bathroom after the plane exploded. The plane left a gash in the roof of one house while the tail and fuselage slammed into another. One of the wings “catapulted” into the third home, Robert Sumwalt of the National Transportation Safety Board (NTSB) told reporters.

The six-passenger plane was owned by Michael J. Rosenberg, a North Caroline biotech executive and reportedly an experienced pilot. It crashed less than a mile from the Montgomery County Airpark. Investigators are still determining the cause.

In 2012 – the most recent year for which final statistics are available – a total of 440 people died in what are known as general aviation  airplane crashes in the United States, according to the National Transportation Safety Board. The preliminary figure for 2013 is 387. The general aviation category covers small planes, gliders, balloons and other aircraft flown by pilots like Rosenberg.

There are several reasons the risks are higher with small planes. For one, they are piloted by people who don’t fly planes for a living. The rules are looser for amateur pilots, who don’t have to log as many flight hours to be certified. Small planes also land at small airports that may not even have paved runways.

The vast majority of general aviation accidents in 2011 happened because the pilot lost control in-flight. Another common cause was “controlled flight into terrain,” which means the pilot didn’t see the ground, a mountain, a body of water or another obstacle until it was too late.

According to the Aircraft Owners and Pilots Association, planes crash almost twice per week because they run out of fuel. Bad landings are the most common cause of non-fatal accidents, while the risk of fatality with bad weather, when a pilot is using his instruments because he can’t see, is much higher.

Captain Sully Sullenberger’s heroic landing on the Hudson River in New York in 2009 after a commercial airplane’s engines sucked in some Canadian geese brought attention to birds as a potential flight risk.

So-called “wildlife strikes,” which cause damage but rarely death, are underreported, so it’s hard to know how common they really are. Between 1990 and 2012, 60 civilian aircraft, mostly small planes, were damaged beyond repair by wildlife, according to a 2013 FAA report. The culprits include Canadian geese, vultures and white-tailed deer.

According to a USA Today investigation, defective parts and dangerous designs may be the cause of small plane crashes that get blamed on pilot error. The report uncovered “wide-ranging defects have persisted for years as manufacturers covered up problems, lied to federal regulators and failed to remedy known malfunctions.” A review by USA Today of lawsuits and internal company records found defects not uncovered by NTSB accident investigations. A few examples:

  • Helicopter fuel tanks that easily rupture and ignite, causing scores of people to be burned alive after low-impact crashes that were otherwise survivable;
  • Pilot seats that suddenly slide backward, making airplanes nose-dive when pilots lose grip of the controls;
  • Ice-protection systems that fail to keep airplane wings clean during flight and fail to warn pilots of dangerous ice buildup that causes crashes;
  • Helicopter blades that flap wildly in flight and separate from the mast or cut through the helicopter tail;
  • Airplane exhaust systems that leak exhaust gas, causing engine fires;
  • Engine carburetors that flood or starve engines and had been causing midair engine failures since at least 1963 when the federal government notified the manufacturer of “a serious problem” with its carburetor that had caused a recent fatal crash.

Among those who have died in small plane crashes over the years: John F. Kennedy Jr., Stevie Ray Vaughan, John Denver, Ritchie Valens, Buddy Holly, Jiles “the Big Bopper” Richardson, Democratic Sen. Paul Wellstone of Minnesota, golfer Payne Stewart and Lewis Katz, a former owner of the NBA’s New Jersey Nets and the NHL’s New Jersey Devils, who died this summer.

An earlier version of this story inaccurately reported the number of people killed in small plane crashes. The story has been corrected.