scsmith
Well Known Member
I posted this in another thread, but no one responded, so I thought I would repost it as its own thread. The lack of responses might be an indicator of what others think of the question, but I'm being serious:
Question for everyone: Does the requirement from the ACK installation manual that: "The antenna must be mounted
within 30 degrees of vertical, when the aircraft is in normal flight attitude" really preclude mounting on the bottom? Isn't it still "vertical" even if it is upside down?
In previous threads many have observed that if I'm upside down, I probably need help more than if I am right-side up, and I would want my antenna performing best then. But that is still a rationalization when it is required to comply with the TSO. But being oriented vertical, on the belly, doesn't that meet the letter of the TSO requirement?
I can imagine that the rationale for the requirement is that the antenna must 'see' the satellites. But I've observed GPS signals getting in and out with a variety of obstructions, so I suspect that mounted on the belly of the fuselage would still radiate out to satellites just fine (except maybe one directly overhead). So, functionally, I think a 406 antenna mounted on the belly would work just fine. Again, what do you guys think?
What do you guys think?
Question for everyone: Does the requirement from the ACK installation manual that: "The antenna must be mounted
within 30 degrees of vertical, when the aircraft is in normal flight attitude" really preclude mounting on the bottom? Isn't it still "vertical" even if it is upside down?
In previous threads many have observed that if I'm upside down, I probably need help more than if I am right-side up, and I would want my antenna performing best then. But that is still a rationalization when it is required to comply with the TSO. But being oriented vertical, on the belly, doesn't that meet the letter of the TSO requirement?
I can imagine that the rationale for the requirement is that the antenna must 'see' the satellites. But I've observed GPS signals getting in and out with a variety of obstructions, so I suspect that mounted on the belly of the fuselage would still radiate out to satellites just fine (except maybe one directly overhead). So, functionally, I think a 406 antenna mounted on the belly would work just fine. Again, what do you guys think?
What do you guys think?
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