While Śukadeva Gosvāmī was narrating various activities of Lord Kṛṣṇa in playing the role of an ordinary human being, he also narrated the history of the battle between the dynasty of Yadu and a demon of the name Śālva, who had managed to possess a wonderful airship named Saubha. King Śālva was a great friend of Śiśupāla’s. When Śiśupāla went to marry Rukmiṇī, Śālva was one of the members of the bridegroom’s party. In the fight between the soldiers of the Yadu dynasty and the kings of the opposite side, Śālva was defeated by the soldiers of the Yadu dynasty. But, despite his defeat, he made a promise before all the kings that he would in the future rid the whole world of all the members of the Yadu dynasty. Since his defeat in the fight during the marriage of Rukmiṇī, he had maintained within himself an unforgettable envy of Lord Kṛṣṇa, and he was, in fact, a fool, because he had promised to kill Kṛṣṇa.
Usually such foolish demons take shelter of a demigod like Lord Śiva to execute their ulterior plans, and so in order to get strength, Śālva took refuge at the lotus feet of Lord Śiva. He underwent a severe type of austerity during which he would eat no more than a handful of ashes daily. Lord Śiva, the husband of Pārvatī, is generally very merciful, and he is very quickly satisfied if someone undertakes severe austerities to please him. So after continued austerities by Śālva for one year, Lord Śiva became pleased with him and asked him to beg for the fulfillment of his desire.
Śālva begged from Lord Śiva the gift of an airplane which would be so strong that it could not be destroyed by any demigod, demon, human being, Gandharva or Nāga, or even any Rākṣasa. Moreover, he desired that the airplane be able to fly anywhere and everywhere he would like to pilot it, and be specifically very dangerous and fearful to the dynasty of the Yadus. Lord Śiva immediately agreed to give him the benediction, and Śālva took the help of the demon Maya to manufacture this iron airplane, which was so strong and formidable that no one could crash it. It was a very big machine, almost like a big city, and it could fly so high and at such a great speed that it was almost impossible to see; so there was no question of attacking it. It appeared to be almost covered with darkness, yet the pilot could fly it anywhere and everywhere. Having acquired such a wonderful airplane, Śālva flew it to the city of Dvārakā, because his main purpose in obtaining the airplane was to attack the city of the Yadus, toward whom he maintained a constant feeling of animosity.