vakakaaa:
"Horizon 101" - means that the aircraft had reached a minimum height of the radar.
The following short extract is an interesting although a rather hasty translation from the testimonies of the two Severnyj ATC operators.
"Pavel Plyusnin, who was head of operations, told the Polish crew the weather conditions: temperature and atmospheric pressure. Especially important was the last figure, as based on this information barometric altimeter was set accordingly. In the records there is no information about what pressure exactly Plyusnin told the pilots.
Victor A. Ryzhenko, assistant head of operations, led the Polish aircraft through the last, most difficult stage of flight, during which the tragedy occurred. Between the Ryzhenko testimony was found another difference. According to one of the protocols, he showed that when the aircraft was just two kilometers from the airfield runway, the indicator on the sensor of the landing radar blink [индикатор на датчике локатора посадки мигнул] (that phrase does not appear in the second protocol). Prosecutors have suggested it could be a time when the Tu-154 wing brushed against a tree. This point was crucial - then the pilots were unable to raise the aircraft back into the air.
Ryzhenko showed that when he gave the command "Horizon", which means a demand for the immediate cessation of landing, the plane was no longer visible on the screen. Which in practice means that the catastrophe was inevitable."
Amendment (27.6.2010). --- 1. I am reading these ATC’s statements from engineers and pilots viewpoint and just repeating here their statements from other sources, without having any interest in speculating anything. One of my main interests is on the coverage (in this case accident time) of NDB, radar etc systems --- 2) My knowledge of their approach and landing procedures has been moderate, but the listed 10 “landing” types (see #491 above) were not officially valid at Severnyj on the 10th April. The airport was not, since Oct 2009, any more in official regular (military) use. Pardon my generally clumsy language, I do reseach in a special place for disabled people.