| Author | EUROCONTROL |
| Title | ACAS Bulletin 2 |
| Summary | One common type of RA is that which is issued when aircraft are expected to level-off 1000 feet apart, and, at the same time, are crossing horizontally. These RAs are often classed as ‘operationally unnecessary’. Why do they occur? |
| Category | Loss_of_Separation |
| View this book |