Now I know why we can feel the rig movement due to the heave more on a tender rig compared to a semi (semi sub or semi tender). It's due to the ballast control. I knew that a semi sub rig like Ocean Rover and semi tender rig like West Alliance or West Berani has a ballast control, to compensate the heave and minimize the rig movement. But I've never realized that a tender rig doesn't have any ballast control. So that's why it's sooo different.
And that's why also, in West Berani and West Alliance, they can use an access ramp (bridge from tender to platform) which is convenience, with spiral stairs and sorts, because the rig movement is minimal. The same reason also why on a tender, we cannot use those kind of access ramp, but a widow maker, or so we call it, which is a lot more dangerous in bad weather where the heave is very high. Due to lack of ballast control from the tender, the rig is moving accordingly to the heave. In that kind of situation, I prefer to stay on the fix platform, eventhough the accomodation and food is down there on the moving tender.
Watching the tender movement from a fix platform will give you a chill on how this thing can move. Just like a boat on a rough weather. It doesn't care how big is the tender, it will still move violently. And imagine you have to climb a ladder down to that kind of moving rig. Or even jump. Man...I really hope I will never ever come across those kind of rig again.
1 year ago