Nearly 45,000 people have been killed in crashes of small airplanes and helicopters since 1964, and while federal investigators overwhelmingly blame pilots, USA TODAY found repeated instances in which crashes, deaths and injuries were caused by defective parts and dangerous designs.
The findings cast doubt on government rulings and reveal the inner workings of an industry hit so hard by legal claims that it sought and won liability protection from Congress.
Our three-part USA TODAY investigation found wide-ranging defects have persisted for years as manufacturers covered up problems, lied to federal regulators and failed to remedy known malfunctions.
Some defective parts remained in use for decades -- and some are still in use -- because manufacturers refused to acknowledge or recall the suspect parts or issued a limited recall that left dangerous components in hundreds of aircraft.
The manufacturers involved have paid hundreds of millions of dollars in settlements that received little or no public attention until now and that need not be disclosed to federal regulators. In addition, civil-court judges and juries have found major manufacturers such as Cessna Aircraft, Robinson Helicopter, Mitsubishi Aircraft, Bell Helicopter and Lycoming Engines liable for deadly crashes, ordering them to pay hundreds of millions of dollars in compensatory and punitive damages.
The verdicts contradict findings of the National Transportation Safety Board, which conducts limited investigations into most crashes of private aircraft and asks manufacturers to look for defects in their parts, even if the manufacturers are being sued over a crash.
Judges and juries have spent weeks hearing cases that took years to prepare and unearthed evidence that NTSB investigations never discovered.
A Florida judge, finding that Cessna had known for "many years" of a potentially lethal defect in thousands of planes but hadn't fixed it, wrote in 2001 that the company could be guilty of "a reckless disregard for human life equivalent to manslaughter."
A USA TODAY review of tens of thousands of pages of internal company records, lawsuits and government documents found defects implicated in a series of fatal crashes of small planes and helicopters. The deadly defects include:
-- 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.
Manufacturers say crashes are caused by pilot errors, aircraft neglect or owners' failure to follow manufacturer bulletins urging parts replacements.
The danger of private airplanes and helicopters -- known as "general aviation" -- far exceeds that of airline flight. In 2013 alone, there were 1,199 general-aviation crashes -- more than three per day on average --killing 347 people, injuring 571 and destroying 121 aircraft.
A domestic passenger airline hasn't crashed since Feb. 12, 2009, when 50 died on Colgan Air Flight 3407 near Buffalo.
While the airline crash rate has plummeted to near zero, the general-aviation rate is unchanged from 15 years ago -- and roughly 40 times higher than for airlines.
"When you look at aviation, the place where people are getting killed is general aviation. Year after year, we are killing hundreds of people in general aviation," said former NTSB chairwoman Deborah Hersman, who left in April to become president of the National Safety Council.
One of the most gruesome and long-standing problems has caused scores of people to be burned alive or asphyxiated in fires that erupt after helicopter crashes. Such deaths are notorious because they occur after minor crashes, hard landings and rollovers that themselves don't kill or seriously injure helicopter occupants. The impact can rupture helicopter fuel tanks, sending fuel gushing out, where it ignites into a lethal inferno.
Using autopsy reports and crash records, USA TODAY identified 79 people killed and 28 injured since 1992 by helicopter fires following low-impact crashes.
Although crash-resistant fuel tanks have been available since the early 1970s, when the Army installed them and dramatically reduced soldiers' deaths, many manufacturers have not bothered, one safety expert said, because of the added cost, which the Federal Aviation Administration has estimated at several thousand dollars per tank.
"If it's cheaper to let you die than to fix it, you're going to die," said Harry Robertson, who invented the crash-resistant "Robbie tanks" for the Army and is in the National Aviation Hall of Fame.