Adding Hobbs Meter

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Lawson Laslo

Pre-takeoff checklist
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How can you add a Hobbs meter to a airplane that doesn't have one?
or would it just as well to use a stopwatch?
 
Lawson Laslo said:
Can you add a hobbs meter to a airplane that doesnt have one?
or would it just as well to use a stopwatch?
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A stopwatch and a Hobbs meter aren't quite the same thing. But of course you can add a Hobbs to any plane, if all you want is to track the time that the master switch is on.
 
A Hobbs meter is activated by an oil pressure switch. Engine running=Hobbs time.

Just add the switch that comes with the meter.
 
Kenny Phillips said:
A stopwatch and a Hobbs meter aren't quite the same thing. But of course you can add a Hobbs to any plane, if all you want is to track the time that the master switch is on.
Click to expand...
what if you just started the stopwatch once you turn on the master? wouldn't it work similar?
Would only need it for logging flight time...
 
You can estimate Hobbs time with 1.2 x tach time.
 
I think the best way is just to upgrade to a certified engine monitor that records hobbs and tach time. I mean it's only going to run about $10k installed.
 
You bought a plane with no Hobbs meter? WTH?!?!?!?

Oh, and the serious answer, don't bother adding one. Spend a few minutes searching this site for "Logging Hobbs Tach"

All the answers are here.
 
Unless you plan on renting the plane out, there's no need for a Hobbs meter.
 
The only purpose that the Hobbs meter serves, is to log flight time. Other than that, all of your times for maintenance inspections come off of the Tachometer.

Use a watch or like @GeorgeC said, just multiply Tach by 1.2 and you’ll have a good estimate to log from.
 
What I have seen in the flight schools are two Hobbs. One is a flight Hobbs running off an airspeed switch and is used for maintenance, the other a normal Hobbs off oil pressure used for billing.

As defined by FAR Part 1, "Time in Service, with respect to maintenance time records, means the time from the moment an aircraft leaves the surface of the earth until it touches down it at the next point of landing."
 
alfadog said:
What I have seen in the flight schools are two Hobbs. One is a flight Hobbs running off an airspeed switch and is used for maintenance, the other a normal Hobbs off oil pressure used for billing.

As defined by FAR Part 1, "Time in Service, with respect to maintenance time records, means the time from the moment an aircraft leaves the surface of the earth until it touches down it at the next point of landing."
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So when a hurricane comes through, that meter starts running. :D
 
Ravioli said:
You bought a plane with no Hobbs meter? WTH?!?!?!?

Oh, and the serious answer, don't bother adding one. Spend a few minutes searching this site for "Logging Hobbs Tach"

All the answers are here.
Click to expand...
It’s a 73 year old airplane
 
IK04 said:
A Hobbs meter is activated by an oil pressure switch. Engine running=Hobbs time.

Just add the switch that comes with the meter.
Click to expand...

I don't think that's always the case. Some may be activated by the master switch instead of oil pressure switch, just depends on how it was wired.
 
Lawson Laslo said:
It’s a 73 year old airplane
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You gotta take these old sum’beaches with a grain of salt - sarcasm abounds.

Stopwatch is fine too. Or just note the time. Good thing with an hour-meter is that it records in 1/10s so you just do simple math and enter into the log book. BUT, in your case, you could just have your instructor keep track and write up your logbook for the first few months, since he/she will always be signing it up to your solo.
 
I wonder, if the hobbs meter appeared and no entry was made, how many pilots and or mechanics would assume that it was there from day one?
 
Tom-D said:
I wonder, if the hobbs meter appeared and no entry was made, how many pilots and or mechanics would assume that it was there from day one?
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Let's try to educate the kid properly and not steer him towards that mentality regardless of how well it works for you.
 
SkyDog58 said:
Let's try to educate the kid properly and not steer him towards that mentality regardless of how well it works for you.
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Do you believe you would know?
 
Here's a recent AOPA article on how Hobbs meters work. It can be activated by oil pressure, master switch, squat switch on an airplane with retractable gear, or probably other criteria. Pick your poison. As others note, there's no reason to install one unless you're renting it as in a leaseback. Tach time is a better indicator of engine wear.

https://www.aopa.org/news-and-media...ht-training-magazine/how-it-works-hobbs-meter
 
I want to get rid of mine. But then I will have a hole with nothing in it and that bothers me ....
 
WannFly said:
I want to get rid of mine. But then I will have a hole with nothing in it and that bothers me ....
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Wouldn't that hole be around the same size as a stopwatch or kitchen timer?
 
asicer said:
Wouldn't that hole be around the same size as a stopwatch or kitchen timer?
Click to expand...

It would but it would serve the same purpose. I am not building time, pretty useless for me. I like the CO2 detector idea... more $$ ... sigh
 
The club's planes all have Hobbs meters that run on an oil pressure switch. We had one that originally ran on the master. That got fixed, quick. I'm paying by Hobbs time and I'll be darned if I will pay for the time it takes to check the lights and other items in pre-flight that require the master switch to be on. That darned Hobbs is expensive enough, as it is. :D
 
The Hobbs on my plane was inop when I got it. We pulled it out and replaced it with a two-USB outlet with a voltmeter in it. I log tach time.
 
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