'Crackler' was a British naval undertaking in parallel with 'Marmalade' and 'Rapier' to transport, land and provide gunfire support for the troops of Brigadier R. E. Le Fleming’s Indian 24th Brigade landed at Abadan on the north-eastern end of Iran’s Persian Gulf coast within the 'Dover' component of the 'Countenance' invasion and occupation of Iran (25 August 1941).
The vessels involved were the sloop Shoreham, minesweepers Seabelle, Zenobia, Ihsan and Indian Lilavati, together with numbers of smaller vessels including Eurekas, dhows and two RAF launches.
Lilavati was an auxiliary minesweeper which had been engaged in local defence duties at Bombay between February and May 1940. The vessel was later refitted in Bombay and then transferred on 12 May 1941 for service in the Persian Gulf. Here the vessel took part in 'Dover', whose primary object was the occupation of Abadan. To achieve that object three simultaneous operations were carried out as 'Crackler', 'Marmalade' and 'Rapier'. The naval tasks in this triplet of undertakings were the destruction or capture of the Iranian warships lying near Abadan; the transport and landing of troops in the Abadan refinery area; the support of the landing by gunfire if required ('Crackler'); the destruction or capture of the Iranian warships lying in or near the entrance to the Karun river and the simultaneous landing of troops to occupy and hold the naval barracks situated on the left bank of the Karun river ('Marmalade'); the capture of Khurramshahr ('Rapier'); the transport and landing of troops at Khazalabad (Khosrowabad); and the support of the operation by gunfire if required ('Mopup').
The complex of operations was under the joint command of Commodore C. M. Graham and Fleming, both embarked in Seabelle as the headquarters ship.
Lilavati was allocated responsibility for the transport of 288 men of the 2/6th Rajputana Rifles and 15 men of the 5th Field Company Sappers and Miners from Basra to Abadan, where the landing was to take place at 08.40 in 25 August.
On reaching Satan’s Gap, Ihsan and Zenobia passed through the channel to the south of Dabbah and Um-Al-Labani islands and maintained station on the starboard beam of Seabelle and Lilavati respectively. After passing Seeba, Ihsan and Zenobia steamed directly into Breim Creek and disembarked troops there. Seabelle and Lilavati continued so as to arrive off Dabbah Spit Buoy at 02.45 and 02.50 respectively, and off Seeba Creek at 04.07 precisely. As the force approached Seeba Creek Lilavati passed Seabelle. Shoreham and Lilavati were ordered to proceed to patrol the river between Khurramshahr and Seeba after landing their embarked troops.
Lilavati remained part of the Basra patrol until 30 December 1941, when the vessel departed to reach Karachi on 5 January 1942 for local defence service.