False Warning Horns

Here's a new one for ya.

Monday I take a friend back to Norfolk (ORF) from Greenville, SC (GMU). It seems like the front prop is hunting a little bit once I hit about 5000' and I have to synch the props frequently. Acted a little bit like a mag, but a mag check at altitude had a reasonable drop and return with the check. And I just had both prop governors overhauled last year at annual.

So anyway . . . I drop him off and head from ORF to Charleston Exec (JZI). As I'm climbing out of 2500' I smell something like burning rubber for about 5-10 seconds (that's how I know my altitude, because I started looking immediately). But . . . the gauges didn't blip, move, or otherwise budge, no power outage, the smell stopped, no smoke, and everything seemed happy (except me). I cautiously continued on (always knowing where "nearest" was) and completed the flight without event.

I get on the ground at JZI and check everything out, and everything appears to be fine.

Yesterday, I'm on my way from JZI to GMU in solid IMC. I'm cruising comfortabley at 160 kt with a tail wind and a smile on my face. Suddenly, a warning horn goes off intermittently while I'm at 6000'. I can't tell if its the stall horn or my gear horn, but I instantly check my airspeed, AI, DG vacuum system, and then cross check against my Garmin 295. As expected, straight and level with no loss of speed. I check my gear, it's retracted, and I've got the amber light still glowing strong.

The warning horn stops after about 10 seconds . . . and never goes off again. I get towards GMU and am on the ILS, and am expecting the worst from my gear, still scratching my head about the horn. Gear comes down perfect on first cycle without event, I land and everything seems fine.

The questions are:

What was the smell out of ORF and what's the deal with the false, intermittent horn?

Anyone had anything like this before?

Keven
________
Herbal Vaporizers

[Pete Somers]

The problem is more than likely the gear warning horn.
Have a look at the micro switch on the front engine, make sure all the wires are connected and the top of the switch is sealed with RTV so that no water can short the switch out.
Had this problem just recently when flying in a rainstorm the gear warning came on.

Pete

[skymaster]

Once mine went intermittent and could not determine if it was front or rear engine microswitch linked to throttle. i cut wires to both. it solved the problem. mechanic repaired it at home base. its annoying but easy repair. James Henderson

[Jerry De Santis]

Keven, I had same problem as Peter. Fly into damp rain clouds and gear warning horn started. It took about 5 trips with the horn blasting in my ear for up to an hour and half before I decided to disconnect the wire on the front engine alarm. Bingo, no more problem. I of course, had it repaired. It appeared that when in raining misty conditions the alarm would sound, fly into dry weather and it stops. These toys of ours do drive ya crazy, don't they!

[Bob Cook]

On the *P* version you can pull the lamp on the gear indicator and the horn will stop.

Not familiar with the other models and if this applies.

You can put some silicone over the back of the microswitch leads and it should stop this occuring. downside is when you need to clean off the silicone to get at the screws to replace the microswitch <G>.

fyi

Bob

[Jerry De Santis]

Bob, good info, thanks. Where did you find that info? Is it in the POH?
Cheers
Jerry

[Bob Cook]

sheee.... don't tell anyone please... !

CPA handbook <G>

just our secret!

Bob

[Guy Paris]

Works on the plain G model also, remove the bulb. It was my rear engine thou, the micro switch hung up. horn was continous once gear was retracted, a bit of zep spray lube took care of that. The front one, the wire broke at an other time, when in percip would start the warning horn. Guy....old72driver....

[GMAs]

Putting silicone on it has been around for years... used to be standard on the factory stuff too.. but, then they quit making them... and in time things get forgotten...

If you have lots of water.. rain and stuff. and like flying in the soup.. then you need to make a little plastic shield out of a coffee container lid... here you can use your oven to heat it and by using little wooden blocks make it droop over remove and it will stay in the shape of a cover... put the screws that hold the whole thing on over the switch... and cover... leaving room at the top for the arm to move freely... the sheld will keep the rain water from blasting in as the plane flys and keeps the switch dry... neet huh.. bet CPA didn't have that one in their book... smile...

Also after getting into ice.. you may find the wires will break off.. from the switch.. ahhh here we use the little sprial wrap over a piece of plastic tigon tubing...over the wire... it keeps the ice from froming on it and keeps the wire protected... also you might want to include the ones that go to the front prop gov as they will flop around when they get coated with ice too...

G.M. GMAs

[stackj]

And if they really did, it would be readily available for only $650