Former U.S. Secretary of Homeland Security Tom Ridge and JetSmarter CEO Sergey Petrossov Source: JetSmarter

Former Homeland Security chief Tom Ridge is now at the center of growing concerns over security and passenger screening at JetSmarter. Following a CNBC investigation into the company last month, JetSmarter, the Florida-based private jet start-up, sent an email to members highlighting its security policies, saying its "proprietary safety and security infrastructure on the ground was designed with guidance from Tom Ridge, the first Secretary of the U.S. Department of Homeland Security, who currently serves on JetSmarter's board of directors." The CNBC report included a video showing a 23-year-old disc jockey, Maurice Paola, exploding with rage on a JetSmarter private jet flight last September. He threatened to kill other passengers on board, including two young children on the flight, according to a federal complaint. The flight was diverted and Paola was arrested and charged with making terroristic threats.

During his arrest, police found marijuana and $13,250 in cash in Paola's luggage, according to the complaint. Passengers and crew on the flight said there was no screening or security check before the flight. Three days before the flight, Paola had tweeted "From a jail cell to the private jet, they can't stop @ me." And on the same day of the flight, he tweeted "Possessed man, get out my way." Ridge said in a statement to CNBC that "JetSmarter's security measures were designed to not only comply with federal requirements but to exceed them." In its email to members, JetSmarter said its security includes TSA No Fly List screening, a background check, on-the-ground security and K-9 bag screening.

K-9 Unit police dog Source: CNBC

In a further statement to CNBC, JetSmarter said it "employs stricter and more deliberately enforced security procedures than other private aviation industry leaders, including fractional jet providers, jet cards, and other shared flight services." JetSmarter made security one of its signature marketing messages after the company launched in 2012. It named Ridge to the board in 2016, saying in a news release that he would advise "our team as we work towards improving and educating the private jet industry in regard to regulatory compliance."

JetSmarter app Source: CNBC

Ridge and JetSmarter declined to comment on any compensation Ridge may have received, or what investment stake or other benefits he may have received from the company. The same year that Ridge joined, JetSmarter claimed to have a valuation of $1.5 billion after a funding round. Yet JetSmarter members and crew on JetSmarter flights say the company didn't always follow its stated security policies. On some flights there was no bag screening or dog checks, they say. On most flights, except those out of Logan Airport in Boston and perhaps a few others, passengers themselves did not have to go through any metal detector or physical screening, as is the case for a vast majority private jet flights. Despite JetSmarter's claim that it checks for "unauthorized explosives, incendiaries, weapons, narcotics, and other items prohibited onboard," passengers say they witnessed drugs and cash on board. One passenger told CNBC that he saw a gun brought on board. Denver resident Daniel Valenti said he was a JetSmarter member who was boarding a flight in Austin, Texas, 2½ years ago when he discovered a fellow passenger was carrying a handgun.

JetSmarter member Daniel Valenti Source: CNBC