Radar Altimeter

[donv]

So my 980 still has the same old Collins Radar Altimeter that it had since it was new. It is interfaced so it no longer has an external display-- it just shows up on the G600, which is nice.

However, and this has been an issue with the airplane as long as I have had it, at cruise it sometimes starts to think there is ground beneath us, and will cycle up and down. It doesn't happen all the time, and I think I've finally figured out that it is related to cold temperatures-- it usually doesn't happen much in the summer.

Anyone else have this? At cruise, if it starts to do this, I just turn it off and turn it back on descending through FL180, when it seems to work fine.

[Adam Frisch]

I have one of those myself in mine. Never looked at it once so far (not even sure it works). But I can see the benefit on dicey approaches or over water etc.

[donv]

I find it to be really nice when doing a visual approach, especially at night. It is great to know you are 1500 feet above the ground.

[appleseed]

I like this site so much I sometimes search around to see if there are any threads I haven’t read.

Does your rad alt still give spurious indications?

Dd it only started happening after they rolled out 5g networks? If so, that’s probably the problem.

[donv]

Yes, sometimes. I think it has more to do with moisture freezing, or maybe condensation, or something. It is definitely related to being cold at altitude, and once I descend down through 10,000 or so, it works fine.

Although the 5g thing could be a factor... it's done it for a long time, I can't remember if it did it when I first got the airplane.