The Interstate Aviation Committee released a statement saying the runway at Vnukovo airport had been visually inspected 1 hour and 20 minutes before the crash.
The friction coefficient of the the runway was checked 15 minutes after the accident, RIA Novosti reported.
"It stood at 0.63, which satisfies the landing requirements for this kind of airplane," the committee's statement said.
Investigators examined the flight recorders of the Tupolev-204 jet, though that information had not been released, Voice of Russia reported. They are considering pilot error, bad weather conditions or technical failure as possible causes of the accident.
There were eight people onboard the jet when it crashed and broke apart on a nearby highway. All eight were airline employees. The pilot was among those killed. Three people remain in critical condition.
Red Wings said Sunday it would cover the medical and funeral expenses for the victims and also pay a sum of 1-2 million rubles ($3.3 million-$6.5 million) to their families, Russia's ITAR-Tass news service said.