Engine Hours G1000

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Kalikiano

New Member
Now the hobbs meter that is its own unit measures time when the master is on.

When does the engine hours (listed on the G1000 Engine system page) start kicking in? and what is used to turn it on
 
Interesting

On a normal flight report you would list hobbs in and out and tach in and out. Do you just list Engine hours as tach in and out?
 
Kalikiano said:
Interesting

On a normal flight report you would list hobbs in and out and tach in and out. Do you just list Engine hours as tach in and out?
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Not every aircraft has a hobbs. The tach usually will tick 1 hour for every 1.2 the engine is running. That's a rough estimate, it depends totally on the RPMs.
 
drunkenbeagle said:
Not every aircraft has a hobbs. The tach usually will tick 1 hour for every 1.2 the engine is running. That's a rough estimate, it depends totally on the RPMs.
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OP, the plane I fly doesn't have a tach but only hobbs, I don't know why. Just thought I'd throw that in there. Plus there are a variety of different ways for a hobbs meter to start running.
 
The Garmin 1000 I fly the Hobbs runs when the engine is running, The tack runs when airspeed is over 35 knots in real time.

I have heard of guys taping the pitot tube so they can squeeze a few more hours in. :whatever:
 
Fly_Unity said:
The Garmin 1000 I fly the Hobbs runs when the engine is running, The tack runs when airspeed is over 35 knots in real time.

I have heard of guys taping the pitot tube so they can squeeze a few more hours in. :whatever:
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Yeah I don't think flying with the pitot tube taped up would be worth it to me. The other day though I left the pitot cover on while I taxied to the fuel pump, and the airspeed was indicating about 50 kts during the taxi. I wonder if the G1000 would count all of that as flight time, and then if I left the pitot cover on, when it would stop counting it.
 
The Cessna G1000 tach hour meter (for mx) operates just like the mechanical -- it's a function of RPM. The external Hobbs starts when the engine is running and an oil pressure switch closes to complete the circuit. The poster who mentioned "35 kts," I believe, is referring to the flight timer function that can be selected to start when the system comes online or when the GPS generated ground speed exceeds a selected value. The same feature is on the 4/500-series panel mount units.
 
I've never seen a plane w/ a hobbs connected to the Master switch. I've heard of it... That sounds awful! But I suppose you could fly around with the master off for free...

Usually any time you have oil pressuure, the hobbs is ticking.. As was previously stated, the tachs turn as the engine does. If it's low rpm, the tach turns slowly. If it's full RPM, the tach should match the hobbs. I have heard of tachs that match the hobbs at any setting above a specified rpm or percentage of rpm.
 
ntbjounin said:
I've never seen a plane w/ a hobbs connected to the Master switch. I've heard of it... That sounds awful! But I suppose you could fly around with the master off for free...

Usually any time you have oil pressuure, the hobbs is ticking.. As was previously stated, the tachs turn as the engine does. If it's low rpm, the tach turns slowly. If it's full RPM, the tach should match the hobbs. I have heard of tachs that match the hobbs at any setting above a specified rpm or percentage of rpm.
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The Turbo Seminole I fly has the hobbs linked directly to the electrical system. I had a student who wanted to experiment with it so I let him for the growth of his knowledge and my own as well. We started up the airplane and shut off the master on the ramp. Hobbs kept ticking. Why? Both alternators were on.
 
Codyjp said:
I my 10 years flying I've never once seen a hobbs meter wired to the master switch but I suppose it could happen.
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In the 152's and 172N models we have, they click the Hobbs with the master switch on. A lot operate on oil pressure from the engine, but operating on the electrical system is quite common, as well.
 
Crism said:
The Turbo Seminole I fly has the hobbs linked directly to the electrical system. I had a student who wanted to experiment with it so I let him for the growth of his knowledge and my own as well. We started up the airplane and shut off the master on the ramp. Hobbs kept ticking. Why? Both alternators were on.
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The hobbs isn't wired to the master. It's wired to the battery, and the switch to turn it on goes through the oil pressure switch. As soon as the engine see's oil pressure, the hobbs starts ticking. It's real simple, just look at the electrical system in the POH. Have we all forgotten about looking to the POH and knowing the airplane we fly?
 
mshunter said:
The hobbs isn't wired to the master. It's wired to the battery, and the switch to turn it on goes through the oil pressure switch. As soon as the engine see's oil pressure, the hobbs starts ticking. It's real simple, just look at the electrical system in the POH. Have we all forgotten about looking to the POH and knowing the airplane we fly?
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You seem so sure, but you are probably wrong. AFAIK, the newer model Seminole's Hobbs runs on the electrical system with no oil pressure switch, while the older runs have the oil pressure switch. Its easy to find out which system you have. If you turn on the battery and you hear the Hobbs clicking, it has no oil pressure switch.
 
Codyjp said:
I my 10 years flying I've never once seen a hobbs meter wired to the master switch but I suppose it could happen.
Click to expand...

ntbjounin said:
I've never seen a plane w/ a hobbs connected to the Master switch. I've heard of it... That sounds awful! But I suppose you could fly around with the master off for free...

Usually any time you have oil pressuure, the hobbs is ticking.. As was previously stated, the tachs turn as the engine does. If it's low rpm, the tach turns slowly. If it's full RPM, the tach should match the hobbs. I have heard of tachs that match the hobbs at any setting above a specified rpm or percentage of rpm.
Click to expand...

If you're in north Mississippi, give me a ring. I'll show you a couple of them with the Hobbs wired to the master. Almost every plane I've flown was set up that way.
 
mshunter said:
The hobbs isn't wired to the master. It's wired to the battery, and the switch to turn it on goes through the oil pressure switch. As soon as the engine see's oil pressure, the hobbs starts ticking. It's real simple, just look at the electrical system in the POH. Have we all forgotten about looking to the POH and knowing the airplane we fly?
Click to expand...

We had the master on during the preflight and I've watched it tick over from .1 to .2. It's wired somewhere in the electrical system. POH doesn't tell us where since it's aftermarket.
 
EVERY single ATP Seminole and Cessna I have flown have ALL been wired to the master switch. And I flew damn near all of them in the 2 years I was there.
 
Crism said:
We had the master on during the preflight and I've watched it tick over from .1 to .2. It's wired somewhere in the electrical system. POH doesn't tell us where since it's aftermarket.
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I have seen then connected to the master (PA30), an oil switch (C172), a weight on wheels switch (BE20), an air switch (1979 PA44, C414), the gear selector switch (BE58). That's all that immediately comes to mind. I'm sure I can come up with some more. Some of those we not in the POH or AFM.
 
msmspilot said:
If you're in north Mississippi, give me a ring. I'll show you a couple of them with the Hobbs wired to the master. Almost every plane I've flown was set up that way.
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Well that 'splains that problem.

wjmiller3 said:
EVERY single ATP Seminole and Cessna I have flown have ALL been wired to the master switch. And I flew damn near all of them in the 2 years I was there.
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One heck of a good way to maximize billing and flight time! Well played on their part!
 
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