FAA approves Trump's triumphal arch, requires 'eternal flame' on top

WASHINGTON - The Federal Aviation Administration approved President Donald Trump's "triumphal arch" near Arlington National Cemetery, after determining that the structure will not pose a threat to aircraft. But, the administration will require some additions to to the arch's design.

FAA approves Trump's arch

What we know:

Trump's proposed arch would be built at Memorial Circle on Columbia Island, between the Lincoln Memorial and Arlington National Cemetery, and just under two miles northwest of Ronald Reagan Washington National Airport.

 The FAA released the results of a hazard study on Friday, determining that the structure will pose no threat to aircraft nearby. But, the designs will have to include some safety features.

Eternal flame required for triumphal arch

Dig deeper:

At more than 250 feet, the arch would stand more than twice as tall as the Lincoln Memorial. The FAA is requiring designers to include an "eternal flame" at the highest point in the structure, to make the arch more visible for pilots. The FAA's plan also requires continuous floodlights around the base of the arch, to keep it well-lit.

Groups suing to stop Trump arch

The other side:

Veterans and preservationists are suing to stop the project. They argue that the Trump administration does not have the authority to build the arch without congressional approval. Several have argued that the arch would be disrespectful to those buried in Arlington National Cemetery.

When will Trump's arch be built?

What's next:

In May, the U.S. Commission of Fire Arts approved the design for the arch despite pushback from the public.

The proposal received early approval in July from the National Capital Planning Commission.

Earlier this month, the Trump administration said excavation for the construction of the arch would begin in just weeks. But, the FAA's findings can be petitioned until Oct. 18. If that happens, they won't be finalized until after that petition is resolved. 

The Source: Information in this story is from the Federal Aviation Administration's Obstruction Evaluation of President Donald Trump's proposed arch and previous FOX 5 DC reporting.