Home > VansAirForceForums

-Advertise in here!
- Today's Posts | Insert Pics

Keep VAF Going
Donate methods

Point your
camera app here
to donate fast.

Go Back   VAF Forums > Avionics / Interiors / Fiberglass > COMM
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Thread Tools Search this Thread Display Modes
Old 05-08-2019, 03:02 PM
n567vb n567vb is offline
Join Date: Feb 2008
Location: MN
Posts: 81
Default Ice on Antenna causing transmission lost?


I recently had a transmission issue with my comm radio while IMC. Based on the following, I'm guessing it was just ice on the comm antenna? Any other thoughts on what it could be?

RV-7, flying for seven years, no issues in the past with the radios. I went for a short IFR flight to stay current on a nice IFR day (2000 ft overcast), no rain, good visibility underneath. All was normal before entering IMC, I was able to contact clearance on the ground at my non towered home base. Took off and communicated back and forth with departure several times. A few minutes after entering the clouds, my transmissions starting getting intermittent and then stopped transmitting. No side tone in my headset and also tried switching to the passenger headset. Same issue. The controller could hear me trying to call, but couldn't hear me. I could receive him just fine. I acknowledged his directions using ident, and I returned to my home field. About a minute after clearing the clouds, I could transmit again. Temps on the ground were right about 40 degrees. There was no ice on the canopy, and I didn't see anything on the wings, but didn't get a could look. If there was anything, it was unnoticeable at quick glance.

I checked the antenna on the ground (it's mounted on the belly), no obvious issue that I could see. I cleaned the antenna (I was able to wipe some dirt off of it) and went up again later in VFR conditions, no issues and haven't been able to repeat the issue.

Based on the above, I figure it has to be something external/environmental, but icing seems to be the only explanation I can come up with.

Reply With Quote
Old 05-08-2019, 07:12 PM
dlloyd3's Avatar
dlloyd3 dlloyd3 is offline
Join Date: Jun 2005
Location: Locust, NC
Posts: 443

No sidetone when transmitting indicates a problem inside the airplane, not an iced over antenna. No sidetone, no voice transmit but controller heard the carrier, could be loose wire or failing radio. Had plenty of ice but no communication difficulty due to it. Flying in heavy rain or snow will cause precipitation induced static, but that is easily recognized.

Last edited by dlloyd3 : 05-08-2019 at 07:17 PM.
Reply With Quote
Old 05-08-2019, 08:56 PM
N941WR's Avatar
N941WR N941WR is offline
Join Date: Jan 2005
Location: SC
Posts: 12,887

Well... I had a friend who couldn't transmit after an encounter with ice.

When he landed he noticed the ice load snapped his antenna off. That doesn't sound like your issue.

If you have a Comant antenna, remove one screw at a time, give the hole a quick turn with your deburring tool, put dielectric grease on the screw and reinstall it. That solved a similar intermittent issue I had.
Bill R.
RV-9 (Yes, it's a dragon tail)
O-360 w/ dual P-mags
Build the plane you want, not the plane others want you to build!
SC86 - Easley, SC

Last edited by N941WR : 05-08-2019 at 09:02 PM.
Reply With Quote
Old 05-08-2019, 11:50 PM
lr172 lr172 is offline
Join Date: Oct 2013
Location: Schaumburg, IL
Posts: 6,735

In my 6, ice always shows on the windscreen and have never seen it anywhere else when not also on the windscreen, excluding occassional pitot freezing. If it is an antenna issue, I would guess ti was related to static electricity. The moisture in the air increases the amount of static electricity produced from air friction on the body.

N64LR - RV-6A / IO-320, Flying as of 8/2015
N11LR - RV-10, Flying as of 12/2019
Reply With Quote
Old 05-09-2019, 12:21 PM
RV8Squaz's Avatar
RV8Squaz RV8Squaz is offline
Join Date: Feb 2006
Location: Senoia, Georgia
Posts: 899

The no sidetone may be an issue. It's possible you just couldn't hear the sidetone over all of the static. BTW, this happens even on airliners. You just have to wait until you exit the clouds and the ice begins to sublimate. It makes communication near impossible sometimes.
Jerry Esquenazi
RV-8 N84JE
Reply With Quote
Old 05-09-2019, 07:53 PM
Bill.Peyton's Avatar
Bill.Peyton Bill.Peyton is offline
Join Date: Sep 2009
Location: St. Louis, MO
Posts: 1,885

Static build upon airframe. Bet you don?t have static wicks!
Bill Peyton
RV-10 - 1285 hours
First Flight Oct 2012
Aviation Partners, LLC

WARNING! Information presented in this post is my opinion. All users of info have sole responsibility for determining accuracy or suitability for their use.
Reply With Quote
Old 05-10-2019, 03:50 AM
FORANE's Avatar
FORANE FORANE is offline
Join Date: Nov 2011
Location: East TN
Posts: 609

Google precipitation static; it's worst in the snow.
Lancair 235/340
RV-9A (2013 - 2016)

Last edited by FORANE : 05-10-2019 at 04:12 AM.
Reply With Quote
Old 05-10-2019, 10:54 AM
n567vb n567vb is offline
Join Date: Feb 2008
Location: MN
Posts: 81

I considered precip static, but wouldn't that affect all communications, not just transmissions? I was able to received ATC just fine
Reply With Quote
Old 05-10-2019, 11:33 AM
larrynew's Avatar
larrynew larrynew is offline
Join Date: Oct 2007
Location: In New Braunfels, ist das Leben schön!
Posts: 921

I've very occasionally had static while IMC. I have 2 radios with the secondary having the antenna on top of the fuselage. Switching to the upper antenna radio has always worked and the static on the primary radio with lower antenna goes away in a minute or two even when still IMC and always goes away when VMC.
Larry New
RV-7A - Built, flew 950+ hrs, sold
RV-10 - Built, flying 250+ hrs
RV-12iS - All kits ordered!
VAF on Annual Autopay

Last edited by larrynew : 05-10-2019 at 02:12 PM. Reason: -s
Reply With Quote
Old 05-10-2019, 11:49 AM
Carl Froehlich's Avatar
Carl Froehlich Carl Froehlich is offline
Join Date: Dec 2007
Location: Dogwood Airpark (VA42)
Posts: 3,276

Originally Posted by n567vb View Post
I considered precip static, but wouldn't that affect all communications, not just transmissions? I was able to received ATC just fine
Typically it would affect reception but not transmission.

I suspect you have another issue to find other than static.


Last edited by Carl Froehlich : 05-12-2019 at 07:48 AM.
Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -6. The time now is 05:06 AM.

The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.