Therefore if a mast has been extended for a long period, and then the locking mechanism is released to bring the aerial down, sections can travel downward quite quickly.
You can help mitigate disasters like that, by repressurizing them before undoing the locking clamps.
You do have a pressure gauge on the mast air feed don't you?
So you record what it was when extended, and can re-pressurise it to that again before letting the clamps off...
Of course, if the ambient temp' is below freezing when you need to take it down in a hurry, take great care...
73 Dave G8KBV.
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