Your leader "Basic Instinct" (Flight International, 16-22 July), made one significant omission. A pilot reacting to a resolution advisory (RA) must tell ATC by calling "TCAS climb/descent". ATC should then stop issuing avoidance instructions.

The Russian SOPs were deficient in two ways and the lack of an R/T call was significant in this awful example - without the second instruction from Zurich the Russian pilot may have hesitated in his initial climb for a few seconds longer, resulting (perhaps) in a very close airprox rather than collision.

It does seem odd that the Russians have developed SOPs that go directly against the philosophy of a mandated safety system. If it is simply a cultural issue with regards following instructions there is an inevitable logic that has led them into this disaster.

Chris Roberts

Bookham, UK

Source: Flight International