public IHttpActionResult Create(AirCraftModel airCraft)
        {
            if (!this.ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            var newAirCraft = new AirCraft
            {
                Model = airCraft.Model
            };

            this.data.AirCrafts.Add(newAirCraft);
            this.data.SaveChanges();

            airCraft.Id = newAirCraft.Id;
            return Ok(airCraft);
        }
        public IHttpActionResult Update(int id, AirCraftModel airCraft)
        {
            if (!this.ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            var existingAirCraft = this.data.AirCrafts.All().FirstOrDefault(a => a.Id == id);
            if (existingAirCraft == null)
            {
                return BadRequest("Such aircraft does not exists!");
            }

            existingAirCraft.Model = airCraft.Model;
            this.data.AirCrafts.SaveChanges();

            return Ok(airCraft);
        }