>During cold wx ops on ground, engine run-up to 50% N1 every hour.
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That one I just don't understand. Just how long do you operate on the ground?
I can't see how after an hour of operation on the ground that a runup is going to change the thermals much inside an engine.
On the other hand a runup to 60% N1 is recommended on most similar size engines every 15 mins to remove any ice built up on the vanes behind the fan.