While the MC-130J crew sets up for another series of plugs, the Caracals keep their distance. Note the Dune de Pila, the biggest sand dune in Europe, in the background.

Helicopters only move into the pre-plug position after the MC-130J crew has tested the two hoses to ensure they have extended correctly and are functioning properly.

The lead Caracal helicopter moves into position while a second Caracal waits for clearance from the MC-130J crew to move to the other side to commence a series of six aerial refuelling plugs.

The third and final sortie of the daily exercise schedule took place after dark, for which the Caracal crews fly the entire sortie with night-vision goggles.

This picture clearly shows the difference in height between the lead Caracal plugged into the basket and the second aircraft.

Typically, the Caracals unplug from the basket before turning within the oval-shaped HAAR track but maintain a close formation with the MC-130J.

All Caracal sorties were flown with a diver on board because the aerial refuelling track used was located over the ocean; the diver provides over watch and notifies the crew each time the other helicopter plugs and unplugs with the basket. The diver also notifies his crew of the positional changes of the other Caracal behind the MC-130J.

Loadmasters from the MC-130J crew observe and help to coordinate the aerial refuelling procedures from the aft cabin door positions.

Exiting a turn within the HAAR track, the MC-130J leads the way before the Caracals return to their aerial refuelling positions.