Arianespace’s first launch attempt in 2018 appears to have gotten the satellites into orbit, even though contact was lost during launch.
From the reports, it appears that contact was lost when the second stage began firing.
Before this, the Ariane 5 had completed 83 straight successful launches, a track record that Arianespace repeatedly touted as justification for its higher rates.
Update: Arianespace is now saying that though they had entirely lost contact with the rocket after the second stage fired, the satellite’s themselves reached orbit.
A few seconds after ignition of the upper stage, the second tracking station located in Natal, Brazil, did not acquire the launcher telemetry. This lack of telemetry lasted throughout the rest of powered flight.
Subsequently, both satellites were confirmed separated, acquired and they are on orbit. SES-14 and Al Yah 3 are communicating with their respective control centers. Both missions are continuing.
It appears that the SES-14 satellite can reach its planned orbit using its own engines. Al Yah 3’s status is less certain.
If these results hold up, I will then declare, for the purpose of my 2018 launch standings, that this launch is a success for Arianespace. Arianespace however will certainly not consider it so, and will need to figure out why it lost contact with its rocket and why the upper stage did not function as planned.