For 24 years, Greg Bell has run a pilot and aviation supplies shop at the English Street location.

The Gee Bee's Aerospace Shop faces one of Essendon's two runaways, from where the Beechcraft King Air light plane took off on Tuesday.

The plane had been in the air for only a short time before it crashed into the Essendon DFO, killing the five people on board.

There have been calls to close the airport permanently and convert it into a park.

But Mr Bell said the airport was not at fault.

"It would never become a park. It will become a housing estate," he said.

"There will be 30,000 more houses on this land. The traffic would create an absolute nightmare."

He said the facility should be kept open for the convenience of business professionals and emergency services personnel who use it on a regular basis.

"It is a city airport," he said.

"It's convenience is underestimated. There are 44 corporate jets based here, four active flying schools are here, emergency services are based here."

Tuesday's crash caused significant damage to the DFO building, causing it to shut indefinitely.

But on Thursday, Essendon Airport was back in action.

The only sign of the tragedy was an Australian flag flying at half-mast

Inside the terminal, Holly's Cafe did steady business in sandwiches and Vietnamese noodle soup.

A group of male students lounged inside flying school, Flight Academy Australia, while the two airlines in operation waited for incoming flights.

Regular visitor Geoff Stephens, who started work at the terminal as a radio technician in 1970, said nothing much had changed inside, with even the polished floors being the same.

"Shows you how durable it is," Mr Stephens said.

The 75-year-old said he could understand some people wanted the airport gone.

"It is very confined now and there is the noise," Mr Stephens said.

"But it was here first. They didn't have to live here."

He said, if closed, the place could be turned into an aviation museum with the runaway preserved and "lots of trees" planted.

Free Spirit Airlines, managing director, Roman Badov said they had been at the airport for the last three years and employed six people.

He said they operated 12 flights every week taking people on business, leisure and medical appointments to and from Murrumbilla in NSW and Burnie in Tasmania.

"Essendon Airport is an essential part of Melbourne. It serves a very important service for the community," Mr Badov said.

"It was a tragic accident, but [talk of closure] is a knee-jerk reaction."

Margaret and James McEwen, who have lived in the same house at Airport West for 58 years, said they were shocked to hear about the accident.

"We were petrified," Ms McEwen said.

"[I've] got a granddaughter who lives on the boundary of the Essendon Airport. It was the the first thing I thought about."

But the couple, who regularly shop at the Runway Plaza at Essendon Fields, said they were not worried about the danger.

"We live at the end of the west runway, a lot of the private jets fly over the top of our house," Ms McEwen said.

"It has never worried us. It was there before us."