Southwest 737 on final approach to Tampa
Great view while landing today at Tampa International Airport. As we came in, we had another plane join us on approach. While this friend looked like he was right next to us, it was not as close as it seemed. However, it got me thinking on what the requirements for plane separation actually are now.
After some research, I found the following information for lateral separation, airplanes that are en route between airports must have at least 5 nautical miles between them. When the airplanes enter the approach controller’s airspace, that requirement goes down to 3 nautical miles. When the airplane is finally in the control of an airport’s tower controller, planes can be spaced much closer if that controller has visual contact with the airplanes or if at least one pilot reports they have the other aircraft in sight.
This visual separation doesn’t apply when airplanes are in the clouds, in which case the controllers keep airplanes spaced about 2 and a half nautical miles apart, more if the preceding aircraft is a heavy (over 250,000 pounds, which would be a 757 or larger) and the following aircraft is not. This limitation is a function of the wake turbulence generated by larger airplanes.
However, because of some technology improvements to corporate jets and airliners, most of the world has adopted the Reduced Vertical Separation Minima (RVSM) standards. This allows aircraft flying above 29,000 feet to be spaced at 1,000 foot intervals. In the past, that number was 2,000 feet apart.
