Static wicks what benefit do they serve?

[Will.iam]

My 1986 252 has static wicks but another 252 made in 1986 does not have static wicks. This leads me to the opinion that static wicks were an option to install but not required. What are the benefits of having them?  I noticed on a brand new airbus 320 that they did not have static wicks on the flap jackscrew covers like the older Airbus 320’s in the fleet. Apparently the latest revision of airbus also have reduced the amount of static wicks. I know they reduce the static build up on airplanes. Does this help lower your chance of getting struck by lightning? Also heard lowering the static helps keep the paint from eroding as fast. Any of this true? Any other benefit?

just curious why some planes have them and some don’t especially when they are the same make and model. 

[carusoam]

LBs got wicks as a standard…

They aren’t going to do anything until… we have huge static issues…

We don’t usually see any static issues flying through air…. At Mooney speeds…

Air doesn’t rub the skin enough for it to show up….

But, fly through something like snow flakes… that starts to generate some interesting static….

Of which the wicks should help…

I don’t have much experience of flying the same plane with and without the wicks…

Soooo… no objective answer to offer…

Best regards,

-a-

[toto]

4 hours ago, Will.iam said:

Does this help lower your chance of getting struck by lightning? Also heard lowering the static helps keep the paint from eroding as fast. Any of this true? Any other benefit?

My understanding has always been that static wicks discharge electricity that would otherwise be discharged via antennas, messing with communications (and potentially navigation). 

[N201MKTurbo]

About the only thing that will charge the plane is flying through a dust cloud or very dry snow. Static discharges will cause snaps and pops in the radios. I have heard that the discharges drive a Stormscope crazy and fill the display with false lightning strikes.

[GeeBee]

Keeps you from going NORDO from a static corona buildup around the airframe.

 

[Mooney in Oz]

Years ago while flying through rain and cloud, my comm had so much intermittent static noise that I could barely decipher radio transmissions. My aircraft engineer recommended static wicks, so I had them fitted. Never a problem with static noise since.

Later I was told by someone that the wicks are only useful for aircraft that fly at a TAS greater than 200 knots. Contrary to this info, mine work well.

5 hours ago, Will.iam said:

Does this help lower your chance of getting struck by lightning?

No, it doesn’t.

[PT20J]

I believe the idea is to continuously drain off static charge to prevent a buildup from causing a corona discharge which will generate radio frequency interference. The possible interference would be more likely to affect sensitive lower frequency receivers such as Stormscopes or ADF. My 1978 J didn't have them and it had no Stormscope. My '94 J has them and it came with a Stormscope, so perhaps they were part of the Stormscope installation. I recall flying my '78 J through heavy rain one dark (and stormy - sorry, couldn't resist) night and I could put my finger on the windshield and cause an eerie corona discharge that didn't seem to affect the VHF navs or comms. I didn't look at the ADF. 

Skip

[PT20J]

They are easily broken by brushing against them, and I lost one that came unscrewed in flight so now I check the security during preflight. Mooney used a couple of different ones -- the wicks I have were about $50 ea. last time I bought a couple from LASAR (which was the only place I could find the right part).

[Fly Boomer]

33 minutes ago, PT20J said:

They are easily broken by brushing against them, and I lost one that came unscrewed in flight so now I check the security during preflight. Mooney used a couple of different ones -- the wicks I have were about $50 ea. last time I bought a couple from LASAR (which was the only place I could find the right part).

I'm hoping these are not Mooney-specific parts.  Lots of airplanes use static wicks -- surely there is a standard part for this?

[GeeBee]

Spruce has them

[PT20J]

17 minutes ago, GeeBee said:

Spruce has them

Mooney used either TCO DD-1W or SPECMAT 10-900-60/1 four inch wicks. This is from the M20J IPC; I haven't checked other models. The DD-1W is about half the price of the Specmat part and readily available. However, the two brands don't look the same, so it looks funny if you mix and match.  My airplane has the Specmats and I believe they are sold through Boeing (formally Aviall). The only retail source I found that stocks them is LASAR, although I suppose anyone with a Boeing account could order them.

Skip

 

[kortopates]

This has come up probably a dozen times. I am very pessimistic on them and still doing an experiment on my 252/Encore. Flown our Mooney in all sorts of weather over the past 20+years, minus TRS penetration, and never had any radio interference problems. From what people say my experiment may not be complete till flying around the northern lights. Not sure when if ever that will happen for my Mooney.  But I think it's hard to blame radio static or loss of nav all due to static that is solved by static wicks. I would have put them on years ago if I really believed the plane needed them.

[A64Pilot]

12 hours ago, toto said:

My understanding has always been that static wicks discharge electricity that would otherwise be discharged via antennas, messing with communications (and potentially navigation). 

This is why they are there, but whether or not they are required is arguable, probably more aircraft don’t have them than do, yet their radios work fine.

ARMY ELINT aircraft have bunches of the things, ELINT is electronic eaves dropping, radio interception, but their radios are probably really sensitive.

look at the number of antennas on this thing

https://en.wikipedia.org/wiki/Beechcraft_RC-12_Guardrail

 

An aircraft can and will generate a static charge even in clean air, anyone who had ever done sling loads on a helicopter will tell you, a hovering helicopter can generate enough static to throw an arc a foot long and knock you on your arse. Remember the Tom Clancy movie where Jack is getting on the sub? It’s true, not Hollywood. I’ve seen it a couple of times, pretty impressive.

AH-64 drags a wire off its tail wheel to ground static when taxiing around, must work because I’ve never seen a crew chief get zapped.

[GeeBee]

Speed makes a big difference. I've had Boeings that had a corona so bad all the comms were barely readable. For whatever reason, the Boeings seems to be the worst. After a number of no or low comm situations, I convinced the Fleet Captains to work with maintenance to improve the bonding and to create a periodic maintenance program. It worked. 

I have created enough static to create a corona on some light planes, but rarely enough to cause serious radio problems, just enough to zap my student's finger really hard when I have them touch the windshield. I've once created enough build up on a King Air to create some pretty good St. Elmo's and on the DC-9s you can get it rolling down the console in the cockpit if the windshield is old with a worn conductive coating.

Do you need them? I sooner have them and not need them than to not have them at all.

Helicopters are a whole other kettle of fish.

[Mooney in Oz]

On 12/28/2022 at 11:30 AM, kortopates said:

This has come up probably a dozen times. I am very pessimistic on them and still doing an experiment on my 252/Encore. Flown our Mooney in all sorts of weather over the past 20+years, minus TRS penetration, and never had any radio interference problems. From what people say my experiment may not be complete till flying around the northern lights. Not sure when if ever that will happen for my Mooney.  But I think it's hard to blame radio static or loss of nav all due to static that is solved by static wicks. I would have put them on years ago if I really believed the plane needed them.

It is probably a phenomenon that rarely happens and it only happened once to me, which was one too many times as I literally had no comms, only static and why I decided to have the wicks fitted.

The phenomenon nicknamed St. Elmos Fire that Skip alluded to in his above post (I recall flying my '78 J through heavy rain one dark (and stormy - sorry, couldn't resist) night and I could put my finger on the windshield and cause an eerie corona discharge that didn't seem to affect the VHF navs or comms.), can result in a striking blue streak surrounding and travelling down the windshield is also static electricity. This is also a rarity that I have seen at night maybe 3 or 4 times in 3,400 hours of night flying, so environmental conditions have to be ripe and why it is so rare. I think Paul this maybe the same reason you have not experienced radio static.

Despite the nickname, St. Elmos Fire is not dangerous, but if you touch it, it could give you a very light static shock, similar to touching a door handle after walking across a carpet covered floor in shoes caused by friction between the soles and carpet.   

[GeeBee]

1 hour ago, PT20J said:

Mooney used either TCO DD-1W or SPECMAT 10-900-60/1 four inch wicks. This is from the M20J IPC; I haven't checked other models. The DD-1W is about half the price of the Specmat part and readily available. However, the two brands don't look the same, so it looks funny if you mix and match.  My airplane has the Specmats and I believe they are sold through Boeing (formally Aviall). The only retail source I found that stocks them is LASAR, although I suppose anyone with a Boeing account could order them.

Skip

 

The TCO on the Ovations can be sourced at Skygeek. DD1-W 

[toto]

1 hour ago, A64Pilot said:

An aircraft can and will generate a static charge even in clean air, anyone who had ever done sling loads on a helicopter will tell you, a hovering helicopter can generate enough static to throw an arc a foot long and knock you on your arse. Remember the Tom Clancy movie where Jack is getting on the sub? It’s true, not Hollywood. I’ve seen it a couple of times, pretty impressive.

Cf Hindenburg ..

[A64Pilot]

12 hours ago, toto said:

Cf Hindenburg ..

I’m one of those that believe in the static theory myself

[PeterB]

A&P here - wicks help to reduce or eliminate accumulated static electricity in-flight.  Helps to reduce radio interference.  

[jaylw314]

Just as a nuance, my understanding is that static wicks SLOW DOWN the discharge of static.  Static bleeds out quickly at corners, and that flow is what causes radio interference.  The wicks are actually resistors that lower this current to mitigate the interference.  True 'static' static wouldn't produce any RF emissions.