There were no airlifts into Ukraine, arms had to cross the border as they have since. The supplies were in small quantities up to the invasion. They were an important help to Ukraine, but you are overstating how crucial they were - as if stingers and NLAWs did the fighting, or as if Ukraine didn't have its Soviet legacy or homegrown systems like Stugna-P which had a much more decisive impact those early months.

Western support at any scale didn't arrive until later in the year.