The trip is fully funded by Veterans' Affairs New Zealand.
"There will be some disappointment among those who are not able to attend," Mr Ottaway said.
Veteran Ron Mayhill, 88, told the East & Bays Courier that the trip was exciting, and something the World War II veterans had not expected.
"Everybody's looking forward to it very, very much. It's been a long time coming. We've never had official recognition. It'll be quite an emotional journey," he said.
Bomber Command crews, who braved anti-aircraft fire and fighter aircraft to bomb German targets, had the highest Allied casualty rate of World War II, with 55,593 men killed, including 1851 Kiwis.
Another veteran, Frank Prebble, said it was important to remember the men who did not come home.
"When you stand at that memorial and think of all those guys that have gone, I think that will be an important moment," Mr Prebble said.
The 70-metre-long memorial, featuring a 2.7m bronze sculpture of a seven-man bomber crew, will stand in London's Green Park.