The discoveries of the 1978 team were astounding to a UK caving audience which was more accustomed to discovering metres of new cave rather than kilometres: a return trip was inevitable.
With the approval of the State Secretary of Sarawak and the Director of Forests, a larger team visited the Park for a 4 month period from December 1980 to March 1981 under the joint leadership of two veterans of the ’78 trip, Andy Eavis and Ben Lyon.
Two years of planning and intense anticipation were rewarded with the discovery of over 50km of new passage. In G.Api, major extensions were made to Cave of the Winds (4.2km) and the adjacent Clearwater Cave (11.2km) which was establishing itself clearly as the mountain’s master-cave. North of Clearwater entrance three new caves were discovered, Water Polo Cave, Leopard Cave and Imperial Cave. In the Melinau Gorge, Benarat Caverns extended by 4.8km and a howling draught from a small entrance revealed the way into the 1.3km Sakai’s Cave. In the north of the mountain, Blue Moonlight Bay Cave added another 9.4km and filled in another blank section on the map, whilst, across the Medalam River, just outside the Park, the smaller mountain of G.Buda was found to be equally cavernous with 5km of passage in the ‘small’ systems.
Life at the remote Medalam Gorge wasn’t without incident however. One team was trapped on the wrong side of a sump, caught by a sudden storm and a rise in water levels; fortunately they were able to self-rescue thanks to an epic free-dive by Tony White. Exploration was also interrupted by serious attacks of fever, now known to be leptospirosis, caused by contamination of food by the ever present forest rats.
Other incidents broke the pace of discovery 600mm of rain fell in one three day period, filling the forest with water. During this period Jerry Wooldridge, the expedition photographer, tripped and fell in a cave, cutting his thigh seriously on razor sharp rock. Jon Buchan, the expedition doctor, was summoned from base camp to sew up the wound, but this involved a heroic, night-time trek through flooded forest by a local team member, Ronnie King. The following day, Jon himself was nearly killed when a section of rotten tree crashed down through the roof of the camp, splitting the hammock on which he was sitting; finally, Dr Pete Bull, a member of the scientific team, succumbed to suspected histoplasmosis and was evacuated to Miri hospital.
But the jewel in the crown of this expedition was the discovery of Lubang Nasib Bagus, Good Luck Cave. Hans Friederich, another one of the scientists, was coming down the Melinau Paku Valley on his way back from monitoring an experiment in the Hidden Valley. He followed the cliff around the southern margin of G.Api and came across a stream running into the Paku river and followed up to where it resurged from a high, canyon entrance. A few days later Andy Eavis, Tony White, Dave Checkley and Danny Lawi made their way into the cave and found the largest natural underground void on earth Sarawak Chamber 12 million cubic metres of utter blackness!