Originally Posted by
Crash one
Expressions like that mean absolutely bugger all to some one who has no clue what it means.
Does it mean "If you descend from high to low you will maybe hit something?"
Is a student likely to imagine it refers to high to low priessure changes at the same level that if not corrected on the subscale will result in the altimeter progressively reading high causing the pilot to descend in order to maintain the altimeter reading?
Sorry to have muddied the waters with ancient adages. For those who don't know, what my expression relates to is if the QNH or temperature falls below ISA, you need to take care. But, as a 32 year, 11,000 hour commercial pilot, I'm happy to hand this discussion back to those who are clearly more knowledgable than myself. Happy altimetry campers....,