A little expert help here...

[usafhaynes1]

http://mooneyspace.com/gallery/image/34054-m20c/

 

Can anyone tell me what this tube protruding out of the bottom of my plane is?  I've researched antenna's and have come up empty.

[Marauder]

It looks like a Com antennae. I have one for my 650 that looks about the same.

[kerry]

It looks like a ADF antenna.  I took mine off and replaced it with a 2nd transponder antenna for a traffic advoidance device.

[usafhaynes1]

I do have an ADF wire antenna on top that I'm about to remove since the airplane no longer has an ADF.  Can anyone confirm it's the second part of the ADF antenna?

I have two solid com antenna's, gps antenna, elt antenna on top.  transponder antenna on bottom and this monstrosity.  I do have a LORAN that is inop and not sure which antenna it's connected to.  I'll be removing the LORAN when I'm ready to install a DME.

[BigTex]

It might be the drain tube for the overhead vent.

[kerry]

Sorry, I think it's a marker beacon antenna.

[Marauder]

Need a better picture!

[OR75]

it is a Loran antenna

 

looks very similar to a CI-122 Loran antenna

 

Best way to confirm is when you remove it, the part number will be writen somewhere near the coax connector.

[Piloto]

Sorry, I think it's a marker beacon antenna.

I agree, it is an old marker beacon antenna for 75MHz. New ones look like a small boat.

 

José

[Marauder]

Until we get a better picture, I think it is a really thin rudder!

[usafhaynes1]

Understood...my plane is in mx hangar until tomorrow (waiting 72 hours for glue to dry on a newly installed fuel sump that was leaking, they basically resealed left tank after install).  As soon as I have access, I will  take better pictures and post them for an accurate assessment.  My hope is that I can remove the object if it's from the Loran.

[OR75]

Sorry, I think it's a marker beacon antenna.

i believe you are right

[takair]

I vote marker beacon antenna.

[Jerry 5TJ]

Yes, it is a 75 MHz Marker Beacon receiver antenna.  To verify:  Measure the length starting from the forward end at the fuselage, around the bend and to the back of the horizontal element.    It will be about a quarter wavelength at 75 MHz, which happens to be exactly one meter in free space.   In English terms, about 39 inches.

 

The smaller boat-hull shaped Marker Beacon antennas are more common now.  Search Ebay and you'll find a bunch of 'em. 

 

Here's a picture of the old style antenna without the airplane:

 

[Marauder]

That is a marker beacon for sure. Did you replace it? I know they are decommisioning them but many still out there.

[usafhaynes1]

It's still on the plane.  What can I replace it with?

[jetdriven]

You can replace it with a Comant CI-102 like we did last week. 140$ from Aircraft Spruce. Enjoy the extra knot of cruise speed. http://www.aircraftspruce.com/pages/av/antenna_markerbeacon/comant102.php

[usafhaynes1]

You can replace it with a Comant CI-102 like we did last week. 140$ from Aircraft Spruce. Enjoy the extra knot of cruise speed. http://www.aircraftspruce.com/pages/av/antenna_markerbeacon/comant102.php

 

Thanks!!!  I'll put it on my growing list of "upgrades"!