What starts the Hobbs meter?

It won't start til you begin stuffing the dollars into the slot
;))

Some are oil pressure driven, others are electric and run off the master. I think there is another kind as well but can't remember what drives it. Anyone?
 
Let'sgoflying! said:
It won't start til you begin stuffing the dollars into the slot
;))

Some are oil pressure driven, others are electric and run off the master. I think there is another kind as well but can't remember what drives it. Anyone?
Click to expand...
Some are connected to a microswitch in the landing gear and measure wheels up time.
 
Let'sgoflying! said:
It won't start til you begin stuffing the dollars into the slot
;))

Some are oil pressure driven, others are electric and run off the master. I think there is another kind as well but can't remember what drives it. Anyone?
Click to expand...
The one in my Citabria is driven by oil pressure. I know this because we recently replaced the pressure switch (oil was dripping on my leg one day.) I hate it when oil/fuel drips on my legs, especially when I'm flying along.
 
My Caravan has a "vane" that comes out of the bottom of the wing. It starts the Hobbs at 70 kts or better. I taxi 5 miles a day at Intercontinental Houston alone .. good thing it doesn't count "Master on"

Eamon
 
:D Hey, that looks like a twin you're standin in front of. Where's a pic with you and the carabu, or ah ah ah the carbivan or what ever?

Dave S.
 
Normally light aircraft Hobb meters are wired hot to the main buss, with a fuse/cb. and is always seeking a ground, which is found when you gain oil pressure which closes the pressure switch allowing the meter to run. This way the engine can be started and the master shut off and the meter will still run. Yet the master can be turned on and the meter won't run if the engine isn't running.

Vanes under the wing and weight on/off switches are used when actual in "service time" is required. such as "Turbine actual runtime" that counts towards a $100,000 overhaul by the manufacturer. These folks can squeek out every last second of time before the required removal at TBO. (Usually the part 135 121 125 guys) and all turbines.
 
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Ken Ibold said:
Some are connected to a microswitch in the landing gear and measure wheels up time.
Click to expand...

Often found on twins...when the gear comes down the hobbs meter shuts off...making it tempting for Part 135 pilot, who get paid by the hobbs hour, to delay lowering the landing gear....which is probably not a good idea.

Len
 
At our club, we have a lot of planes where the master starts the Hobbs, but one where it's something engine-related (probably oil pressure).
 
Dave Siciliano said:
:D Hey, that looks like a twin you're standin in front of. Where's a pic with you and the carabu, or ah ah ah the carbivan or what ever?

Dave S.
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Hey Dave! Wassup? :)

Yea, that is the Areostar I flew taken at Key west, FL.... Sweet plane. I would think of getting one if I could affore the upkeep. The sell for around 100K$ (Cheap)

Eamon
 
MSmith said:
At our club, we have a lot of planes where the master starts the Hobbs, but one where it's something engine-related (probably oil pressure).
Click to expand...

Our club's C-172H used to do that until I complained. I really hate to have the Hobbs running while I'm pre-flighting (dropping flaps, checking lights and pitot heat, stall warning, etc). It now properly depends on the oil pressure coming up after engine start. We pay by Hobbs time, so paying to pre-flight just doesn't seem kosher.
 
Eamon said:
Hey Dave! Wassup? :)

Yea, that is the Areostar I flew taken at Key west, FL.... Sweet plane. I would think of getting one if I could affore the upkeep. The sell for around 100K$ (Cheap)

Eamon
Click to expand...

Hey Carivan guy :)

Yea, from what I understand, purchasing and errorstar is the cheapest part of the transaction. Fast, sleek, one door under a prop, and parts and skilled mechanics that are getting very difficult to find. But it sure is fun to fly.

Best,

Dave S.
 
Dave Siciliano said:
Hey Carivan guy :)

Yea, from what I understand, purchasing and errorstar is the cheapest part of the transaction. Fast, sleek, one door under a prop, and parts and skilled mechanics that are getting very difficult to find. But it sure is fun to fly.

Best,

Dave S.
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Friend of mine owns an Aerostar. He does like it, but maintenance can be difficult. He has owned a Beech 18 and a Merlin. He says the Aerostar is great to fly and OK on maintenance if you have the right folks (but then again, look at the comparison). His prior plane was a Baron (non-P), and he likes the Aerostar better than the Baron.

Watch the loads, Aerostars are critical on the loading, take a lot of runway, and really won't fly on one with a full load. The crash at Lakeway last summer was an overloaded plane on a short runway....
 
Flight time ia all time from out of the chocks till we're back into the chocks. Time in service is measured on the Hobbs which starts running when weight is off the wheels.
 
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