Name that Antenna

[RoundTwo]

What is this. Is it a fossil?

[PT20J]

Wow, sure has a lot of screws - and not all the same size. From the logo, it looks really old. I think it might be for a radar altimeter.

[PT20J]

Yep, it’s a radar altimeter antenna. I found one for sale on eBay.

[RoundTwo]

Interesting. In front of that there’s also a very large doubled up section over the wing skin, both top and bottom, that looks to be almost 1/8” thick and about 18” along the LE and probably 14-16 inches front to back. There’s a noticeable bulge on the underside and I was told that was the radar altimeter antenna.

I guess I need to do some more googling for that one. Too bad I didn’t get a picture. 

[takair]

Many systems have a pair of antennas, a transmit and receive.  They are typically about 2 feet apart.  Can’t recall this particular config.

[RoundTwo]

9 minutes ago, takair said:

Many systems have a pair of antennas, a transmit and receive.  They are typically about 2 feet apart.  Can’t recall this particular config.

Here’s a very poor photo of the inboard edge of the doubled section. (On the very left edge of the photo) The thickness is what’s so intriguing. 

[takair]

I did your plane have weather radar at one time?  Hard to see in picture, but I’m thinking your talking about the Radome.

[Jerry 5TJ]

The doubler covers or replaced the in-wing radome for a Weather Scout radar.   

[RoundTwo]

25 minutes ago, Jerry 5TJ said:

The doubler covers or replaced the in-wing radome for a Weather Scout radar.   

Here’s a better picture. Is this from Weather Scout? It’s quite large.

[RoundTwo]

55 minutes ago, takair said:

I did your plane have weather radar at one time?  Hard to see in picture, but I’m thinking your talking about the Radome.

It’s a plane I’m looking at. I can’t see any mention of weather radar in the logs. I attached a better picture above. 

[takair]

8 minutes ago, RoundTwo said:

It’s a plane I’m looking at. I can’t see any mention of weather radar in the logs. I attached a better picture above. 

That definitely looks like it had provisions for weather radar.  Basically they closed out the opening.  Alternately, it is a patch for damage to the leading edge.  Would look at the old weight and balance to see if it had radar.  If not, look for log entry for damage repair.

[RoundTwo]

3 minutes ago, takair said:

That definitely looks like it had provisions for weather radar.  Basically they closed out the opening.  Alternately, it is a patch for damage to the leading edge.  Would look at the old weight and balance to see if it had radar.  If not, look for log entry for damage repair.

I’m quite certain it’s not a repair. The overlay/doubler is extremely thick, like 1/8” and has rounded edges as can be seen in the photo. And there’s a noticeable bulge or protrusion on the underside, like it needed the extra space to fit a forward looking antenna. I should have gotten a picture of it.

[takair]

29 minutes ago, RoundTwo said:

I’m quite certain it’s not a repair. The overlay/doubler is extremely thick, like 1/8” and has rounded edges as can be seen in the photo. And there’s a noticeable bulge or protrusion on the underside, like it needed the extra space to fit a forward looking antenna. I should have gotten a picture of it.

It may be the original fiberglass radome that is painted over.  Tap test may reveal the material.

[takair]

Some more here, including parts breakdown.

 

 

[LANCECASPER]

4 hours ago, RoundTwo said:

What is this. Is it a fossil?

The fact that the shop who removed the Radar Altimeter didn’t remove the antenna and probably the wiring may tell you something about the quality of panel works they did. That should have been removed and taken off of the weight and balance. If it’s not in the logs that should really tell you something.

[RoundTwo]

14 minutes ago, LANCECASPER said:

The fact that the shop who removed the Radar Altimeter didn’t remove the antenna and probably the wiring may tell you something about the quality of panel works they did. That should have been removed and taken off of the weight and balance. If it’s not in the logs that should really tell you something.

The radar altimeter is still installed, INOP, but installed. However, there’s no sign of the weather radar left in the cockpit but I’m almost positive the radar antenna is still in the wing as indicated by the bulge on the underside of the wing where I think the movable antenna has come to rest.

[RoundTwo]

32 minutes ago, takair said:

Some more here, including parts breakdown.

 

 

Very informative. Thank you for finding this.

[RoundTwo]

43 minutes ago, takair said:

It may be the original fiberglass radome that is painted over.  Tap test may reveal the material.

Here’s something from the IPC.

[RoundTwo]

43 minutes ago, LANCECASPER said:

The fact that the shop who removed the Radar Altimeter didn’t remove the antenna and probably the wiring may tell you something about the quality of panel works they did. That should have been removed and taken off of the weight and balance. If it’s not in the logs that should really tell you something.

Your point about quality of work during an uninstall is spot on. Check out the leftover slew switch. I don’t think that is of much use for the G5. I wonder how much UL is being used up hauling around 40 years of abandoned components and harnesses.

[RoundTwo]

4 hours ago, PT20J said:

Yep, it’s a radar altimeter antenna. I found one for sale on eBay.

So all of the small screws hold the antenna together and the 8 larger headed screws hold it into the wing. 

[ZuluZulu]

On 1/12/2023 at 1:22 PM, RoundTwo said:

So all of the small screws hold the antenna together and the 8 larger headed screws hold it into the wing. 

And here I was thinking Bendix King had accidentally ordered way too many screws.