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PFM
23rd Jan 2001, 15:20
My question is about ground pointers Vs sky pointers. Most larger aircraft > 5700kg have sky pointers. Why is this? Also why do pilots used to using ground pointers get disoriented when first using sky pointers?

DCDriver
25th Jan 2001, 02:29
PFM, I may be wrong but I think the reason is :
back in the days when cockpits were painted matt black and Smiths provided the instruments, the british way was to have a ground pointer in the artificial horizon ( these were also the days before this instrument became the "ADI").
Today, most large a/c have sky pointers on their ADI's because that's the way american instruments have, I believe, always been designed, and most of these instruments are manufactured in North America.
I personally prefer skypointers, but it's probably just that I'm used to them.

I don't recall becoming disorientated when changing from one type to another, although I did hear of the CAA at the time expressing concern that sky pointers might be confusing ....well they would, wouldn't they?

411A
25th Jan 2001, 05:24
Altho trained on heavyjets in the USA, I must admit that the "ground pointer" is/was not a bad idea. Also have flown aircraft with ground pointers on the pilots' ADI's and sky pointers on the standby ADI. Hmmm, not a good idea but it was allowed by a certain (third world) regulatory authorty. Never found it much of a problem to operate from one day to the next with different displays. Same with Collins "V" bars or Sperry crosspointer F/D displays.