public async Task <RedirectToActionResult> DeleteAntenna(Guid id)
        {
            //get session id (we will use it when updating data and handling errors)
            sessionID_s = HttpContext.Session.GetString("Session");
            sessionID   = Guid.Parse(sessionID_s);
            Data current = new Data();

            Program.data.TryGetValue(sessionID, out current);

            try
            {
                _session.BeginTransaction();
                await _session.DeleteAntenna(id);

                await _session.Commit();

                current.message = "Radar " + id + " removed From Database";
            }
            catch (Exception e)
            {
                // log exception here
                current.message = e.Message.ToString() + " Error";
                await _session.Rollback();
            }
            finally
            {
                _session.CloseTransaction();
            }
            return(RedirectToAction("Edit", "EditRadar", new { id = current.Radar.ID }));
        }