Severstal Air Company provides a submission form on their website for pet owners to fill in before acceptance on board. You can find this at the website link provided.
Pets in the Cabin
Small pets are permitted to travel in the cabin if the combined weight of the pet and carrier does not exceed 11 lbs (5 kg). Animals must remain inside their carrier for the duration of the flight. There is an excess baggage fee for pets traveling in the cabin that varies depending on the destination of your travel.
Pets in Checked Baggage
Animals who exceed the maximum weight to travel in the cabin may be accepted for transport as checked baggage instead. There is an excess baggage fee for pets traveling as checked baggage that varies depending on the destination of your travel. To find out more information, you can contact Severstal Air Company directly at (+8) 8202-675-211.
For pets traveling in the cabin, carriers must not exceed the combined dimensions of 45" (115 cm). For pets traveling as checked baggage, carriers must be shock-resistant, secure, waterproof, covered, made of non-toxic material, and be easy to lift and carry.
Severstal Air Company ask passengers with dogs to bring a Veterinary First Aid Kit on board with them.