The 78-year-old pilot who crashed his plane on Molokai on Dec. 10, killing himself and his wife, was flying without the medical certification required to fly his Cessna 206 aircraft.

Federal Aviation Administration records indicate William Vogt did not renew his third-class medical certificate, which expired in March, or complete a course offered as an alternative to the medical certificate.

The National Transportation Safety Board is now investigating the crash, which took place in the early afternoon roughly 4 miles west of the airport on Molokai.

The cause of the crash is unknown, although there were reports of clouds and fog in the remote vicinity of the downed plane.

Vogt, a retired Kahala dentist living on Molokai, and his 74-year-old wife, Lynn Vogt, a former Kamehameha Schools teacher, were identified as the victims.

Whether a health issue played any role in the accident has yet to be determined.

Medical certification for pilots has been a much- debated topic within the general aviation community in recent years, prompting Congress last year to approve a compromise offering an additional route to certification.

Aviation experts say medical certification is increasingly difficult to obtain and maintain as pilots grow older and are more prone to physical ailments and medical problems.

It can prompt some pilots to defy the law and forgo the requirement.

Robert Katz, a corporate pilot and flying instructor from Dallas, said it’s becoming increasingly common for pilots getting up in age to become scofflaws when it comes to medical certification.

“It’s like giving up the keys to your car. No one wants to be told they can’t fly anymore,” said Katz, a 58-year-old veteran airman who monitors plane crashes across the nation.

In order to fly a private plane, one must either obtain a third-class medical certificate or pass a BasicMed course, along with a doctor’s examination.

Without proof of either, pilots face possible fines and even revocation of their pilot’s license. What’s more, insurance companies are likely to refuse to pay out in an accident.

Until this year the FAA offered only one medical certification option for private pilots and flight instructors: a third-class medical certificate. Obtaining a certificate requires a physical examination by an FAA-designated aviation medical examiner. It is valid for five years for pilots under age 40 and two years for pilots age 40 and over.

The examination is a pass-or-fail test. Pilots who fail can go through an appeals process, but it can be time-consuming and expensive.

Following a lobbying effort by the aviation community, Congress last year authorized a new way for pilots to become medically certified.

Starting in May, pilots with a valid driver’s license were allowed to opt for the BasicMed program, which requires completion of a medical education course, a medical examination by any state-certified physician every four years and complying with various aircraft and operating restrictions. The certification is good only in the U.S.

The new requirement was seen as a compromise to allow an aging population of U.S. recreational pilots to continue flying under a less demanding and less costly system of FAA medical oversight.

“Private flying is just like driving a car,” said Peter Forman, a former airline pilot and Hawaii aviation expert. “The risk to society is minimal.”

Forman acknowledged that the older one gets, the harder it is to pass the medical certification. Additionally, he said, maintaining the certification can be expensive, especially if one has issues that require yearly certification or an appeal to a denial.

Forman said the new BasicMed option is more attractive to older pilots who don’t want to jump through the strict FAA medical hoops.

“Some pilots who are a little older don’t want to go through the rigors of an (aviation medical examiner) physical,” agreed Robert Moore, president of the General Aviation Council of Hawaii.

Moore, a former flight school owner and instructor, recently completed the BasicMed course, and he said he saved money by going to his own physician.

Moore and Forman said most pilots abide by the rules and want to do the right thing in order to keep flying.

But Katz said he thinks a number of older pilots skirt the law to avoid being told they can’t fly anymore.

A pilot who knowingly flies a plane without the proper medical certification presents a risk to the populace on the ground, Katz said.

“These planes can come down anywhere,” he said.

Katz said there’s nothing to stop a person with a potentially serious medical issue from climbing into the cockpit of an airplane.

“It’s an honor system that is easy to abuse,” he said. “It’s the fox guarding the chickens.”