Pakistan Army and Air Force salute with palm facing out and in the early years of these services, the PAF salute was at a slight angle (as per RAF traditions). Over time, the PAF and PA salute became the same with palm out however the PN salute remained with the hand flat but slightly at an angle to the eye brow. If you see a PA or PAF officer saluting with a slant (similar to the American salute) then it is simply a lazy salute and not per regulation. I have seen this laziness in some of the senior officers too and it is a shame.
Most officers who take pride in wearing the uniform will always salute crisply with a proper turn out. The whole purpose of the saluting test so early on in the respective military academies is to instill in future officers the importance of saluting properly.
Of the recent CoAS of the PA, Gen. Raheel Sharif was the most particular about saluting exactly as per the regulations. Gen Kayani, not so much.
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