Stall warning horn + light ?

Southpaw

Line Up and Wait
Joined
Aug 4, 2019
Messages
529
Location
Montana
Display Name

Display name:
Ernest Taft
I have trouble hearing the stall warning horn. Can a light be wired into the same Circut ?
It's on a 172 , the 150 is a bit louder.
 
There is no circuit on the stall warning on a 172 (unless you meant 172RG). It's an air horn. You can get a new horn though. I don't know if a new one would be louder than an old one but they're cheap so worth a try. And/or maybe the problem is that it's not sensitive enough. The opening on the wing leading edge can be adjusted upward to make it more sensitive.
 
I have trouble hearing the stall warning horn. Can a light be wired into the same Circut ?
It's on a 172 , the 150 is a bit louder.

There is no circuit on the stall warning on a 172 (unless you meant 172RG). It's an air horn. You can get a new horn though. I don't know if a new one would be louder than an old one but they're cheap so worth a try. And/or maybe the problem is that it's not sensitive enough. The opening on the wing leading edge can be adjusted upward to make it more sensitive.
Probably a bad reed. Had a similar issue on a leaseback 152 a few years ago.
 
There is no circuit on the stall warning on a 172 (unless you meant 172RG). It's an air horn. You can get a new horn though. I don't know if a new one would be louder than an old one but they're cheap so worth a try. And/or maybe the problem is that it's not sensitive enough. The opening on the wing leading edge can be adjusted upward to make it more sensitive.
Depends on the 172 model. The early ones (up to and including the G model, I believe) were a small vane which operated a microswitch and a Safe Air horn. The models after that have the party horn style.
 
I have trouble hearing the stall warning horn. Can a light be wired into the same Circut ?
It's on a 172 , the 150 is a bit louder.

This link has a diagram of the 172 type stall system with stall horn reed. https://www.aopa.org/news-and-media...ght-training-magazine/how-it-works-stall-horn

The least expensive fix - https://www.aircraftspruce.com/catalog/appages/cessnapart36.php



The expensive fix, https://www.aircraftspruce.com/cata...MI2OqU0qKr5gIVEr3sCh3I9gWLEAQYAiABEgIqNfD_BwE
 
Last edited:
I can't believe I'm making this recommendation, and I'm actually serious.

Get an AoA indicator. Preferably the HUD type. I think they some have an output to the audio panel.
 
It's basically a kazoo
 
I always had a hard time hearing the Cessna stall horns

*I'm in the AoA camp though.. it's a more intelligent tool and if used correctly could help cut down on stalls / spins on the base to final turns
 
Depends on the 172 model. The early ones (up to and including the G model, I believe) were a small vane which operated a microswitch and a Safe Air horn. The models after that have the party horn style.

I stand corrected. Didn't realize the design had changed, but that's what I get for not checking first.
 
I always had a hard time hearing the Cessna stall horns

*I'm in the AoA camp though.. it's a more intelligent tool and if used correctly could help cut down on stalls / spins on the base to final turns

AOA is more useful, but also I'd install a new Reed for the stall horn. The reed does not require power and makes a fail safe design in the event of power failure. Also might check the regs, as the factory stall horn I believe is mandatory.
 
You can get new party horns from the junk dealers (like Wentworth Aviation) for very small dollars (I seemed to recall seeing a pile of them in their booth at Oshkosh for $15 each or something like that). But unless there's something wrong with the existing one, replacing it isn't going to make it louder.
 
*I'm in the AoA camp though.. it's a more intelligent tool and if used correctly could help cut down on stalls / spins on the base to final turns
An AOA Instrument is more intelligent, but the Cessna stall horn IS an AOA indicator. It’s merely an on/off indicator of a specific AOA.
 
You can get new party horns from the junk dealers (like Wentworth Aviation) for very small dollars (I seemed to recall seeing a pile of them in their booth at Oshkosh for $15 each or something like that). But unless there's something wrong with the existing one, replacing it isn't going to make it louder.

I’ve never seen one, but it might be fun to buy one keep it hidden when your buddy is flying, blow it somewhere up high to get his attention (not in IMC and not near the ground).
 
Thank You. I just bought this 1959 year 172 and have only flown it 1.2 hours after delivery. My CFI and I went up and did stalls . Both turning power stalls and slow flight stalls. It recall back in the early 70's the Piper 140 I took lessons in had a light that would flicker to stay lit when approaching or in a stall .
The LED light one looks interesting .
 
Your 1959 should have an electric horn now, correct? SafeFlight I believe does make a version of the sounder that includes a light. I can tell you that it isn't cheap. (We're talking around $2000). Even used, the electric audio only horn goes for $200.
 
Your 1959 should have an electric horn now, correct? SafeFlight I believe does make a version of the sounder that includes a light. I can tell you that it isn't cheap. (We're talking around $2000). Even used, the electric audio only horn goes for $200.
The owners manual says it has an electrical operated horn.
Still wondering if one can put a LED light (low current draw) in Circut.
Guess next time I get to hanger (it's 40 miles away) I will have another look.
 
Still wondering if one can put a LED light (low current draw) in Circut.
Anything is possible. Something like that is in the gray area whether a minor/major alteration so why not inquire with your mechanic?
 
Wow! I actually learned something from Clip4 (painlessly)!

Been looking at AOA indicators... And the CYA unit looks a treat.

Thanks, Clip... I don't care what the others say 'bout you, you ain't half bad... (Go ahead, include me in "others").
 
I have trouble hearing the stall warning horn. Can a light be wired into the same Circut ?
It's on a 172 , the 150 is a bit louder.


My electric fuel boost pump, (I fly a low wing), has a panel mounted light that I had installed. Prior to that, the only indication that the pump was energized was the fuel flow gauge or looking directly at the switch itself. Too many times I would leave the pump on after switching tanks or shooting missed approaches, etc. Well the light is still easy to miss. However, a noisy, loud, obnoxious, continuous, audible warning is impossible to ignore. I’ve had my bacon saved more than once by a loud audible warning. I would go for a loud alarm. An AOA indicator would be a better investment as a light but only in addition to a loud stall warning horn. JMHO
 
My electric fuel boost pump, (I fly a low wing), has a panel mounted light that I had installed. Prior to that, the only indication that the pump was energized was the fuel flow gauge or looking directly at the switch itself. Too many times I would leave the pump on after switching tanks or shooting missed approaches, etc. Well the light is still easy to miss. However, a noisy, loud, obnoxious, continuous, audible warning is impossible to ignore. I’ve had my bacon saved more than once by a loud audible warning. I would go for a loud alarm. An AOA indicator would be a better investment as a light but only in addition to a loud stall warning horn. JMHO

A AOA indicator and heading indicator will be on the ForeFlight on the I pad. I have to change out the panel mount from the mini 3 to a mini 5 mount 'Just arrived today so it's waiting for a sunny day to install.
With the noise canceling head phones turned off I can hear the stall horn.
 
An AOA Instrument is more intelligent, but the Cessna stall horn IS an AOA indicator. It’s merely an on/off indicator of a specific AOA.
As I recall (been a l-o-o-n-g time since I've flown a Cessna, or indeed any aircraft with any kind of stall warning device), the air horn would change in pitch and volume as you approach the stall, so it's more than just on/off. I seem to remember practicing slow flight with the horn just softly whining...
 
As I recall (been a l-o-o-n-g time since I've flown a Cessna, or indeed any aircraft with any kind of stall warning device), the air horn would change in pitch and volume as you approach the stall, so it's more than just on/off. I seem to remember practicing slow flight with the horn just softly whining...
True...how about an indicator of a very small range of AOA?
 
Back
Top