National Business Aviation Association (NBAA) president and CEO Ed Bolen sent a letter to Congress and President Barack Obama stating that the general aviation industry has been grounded by the shutdown, with an inability to buy and sell aircraft, comparing the situation to an American economy where citizens are unable to buy and sell cars or purchase and re-finance homes.

The government shutdown entered its seventh day on Monday, with hundreds of thousands of federal workers remaining furloughed, including FAA workers at the Aircraft Registry in Oklahoma City, OK. FAA data shows that more than 10,000 aircraft registrations expire monthly, and operators are unable to renew these registrations when the registry is closed, therefore leading to an essential grounding of the general aviation industry.

The agency has furloughed about 100 of its 1,200 certification inspectors, with the remaining workers not able to initiate any new certification projects and support smaller companies that directly rely on FAA for design approvals, according to a statement issued by Aerospace Industries Association (AIA) president Marion Blakey on Friday.

“This shutdown is also impacting the thousands of businesses that use those aircraft for parts delivery, to visit customers, those that repair aircraft, sell fuel, build hangars, and broker airplane transactions.

Collectively, the situation threatens to have a ripple effect through communities with regard to critical services that depend on these aircraft – everything from medevac flights, to mail delivery, transport of veterans, fire-fighting, and blood, organ and medical transport,” Bolen wrote.

The NBAA CEO also highlighted data from the General Aviation Manufacturers Association (GAMA) which estimates the value for near-term deliveries halted by the shutdown to be at $1.38 billion. The fourth quarter is the peak time for aircraft deliveries, accounting for 35% of annual aircraft deliveries, Bolen said. The backlog piling up if the shutdown becomes lengthy could “devastate the industry’s fourth-quarter deliveries,” Bolen said.

According to Bolen’s letter, the aircraft registry shutdown is also a “violation of international treaties and obligations,” resulting from FAA’s February 2012 policy statement on aircraft registrations, which states that the agency is obligated to “provide information on the registration and ownership of aircraft on its registry” when requested by another contracting State or the International Civil Aviation Organization.

“Until the FAA Registry in Oklahoma City opens, an important American industry remains on an indefinite layover,” Bolen said.