To be effective, all these aircraft required an environment of local air superiority and fighter escort.
On top of this the aircraft required a proper airfield on which to land.
Super and heavy-category aircraft require greater separation behind them than those in other categories.
Larger aircraft used by low-cost airlines, such as Boeing 737s, require longer runways.
These aircraft do not require paved runways and can take off or land in a very short distance.
What aircraft require a type rating is decided by the local aviation authority.
In the 1940s the city was growing rapidly and new aircraft of the time required better facilities.
For example, an aircraft requires a much longer life span than other types of investment in order to be adequately paid off.
The aircraft would require export licenses similar to the F-35.
The number is not particularly high by Western standards, although aging aircraft require more inspections than newer planes.