Fooling Mr. Hobbs

RalphInCA

RalphInCA

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RalphInCA
The Hobbs on the airplanes I fly activate when the master is turned on.

If I turned the master switch off during flight, this should stop the Hobbs, right?

If I'm in an area where I will not need the radios, what's to stop me from turning off the master to stop the Hobbs and fly for free?
 
When the FBO checks the books and sees that the tach time is significantly higher than the hobbs time... Might start to raise a red flag, but it could be done.
 
You're really that concerned about saving a buck? Never get into aircraft ownership. It's essentially throwing cash into a fire.
 
The tach does not lie. The FBO might not be able to identify who was flying the plane when the Hobbs and the tach began to differ appreciably, so it is between you and your conscience.

Bob Gardner
 
Yeah go ahead. Ruin it for everyone else. :rolleyes:
 
No prob. Just expect that per hour rate to increase. You will pay one way or another. Or buy your own plane and do whateverthehellyouwant to it.
 
bobmrg said:
The tach does not lie. The FBO might not be able to identify who was flying the plane when the Hobbs and the tach began to differ appreciably, so it is between you and your conscience.

Bob Gardner
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Hmmm.

So, what I should do is climb at Vy, to about 10k, shut off the master and shut the engine off and glide. Then I can fly for free.

That conscience thing will be a little tougher...
 
Most Hobbs meters only run when the engine is running. If it runs whenever the master switch is on, then you're getting charged for things like calling the fuel truck, and pre-flighting the lights, pitot heat, and stall horn.
 
Palmpilot said:
Most Hobbs meters only run when the engine is running. If it runs whenever the master switch is on, then you're getting charged for things like calling the fuel truck, and pre-flighting the lights, pitot heat, and stall horn.
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Yep, I sure am. It's annoying

I got in trouble once for sitting in the airplane and fooling around with the Garmin 430, trying to figure it out. Without knowing it I ran up the Hobbs.
 
The plane I fly does the same thing. Although I never tried turning off the master. I turn it on to drop the flaps and check to make sure the fuel gauges are working. Then turn it off and do the rest of the preflight. One of the other planes I fly just has a tach and I like that much better. :)
 
It all comes down to, what type of person are you. (none of us care and I certainly am not judging; this is a question I am suggesting you should be asking yourself).

When you lay your head on your pillow at night, will you fall into an easy slumber knowing you have not taken that which is another's? Or will you toss a little bit? Maybe you will sleep a while then jerk awake, without realizing why.

Then there is the whole karma ***** thing.
 
So I go rent the plane. I check the book and see it last flew 0.2 and that was the first flight of the day, I'm next. On the way out the door I ask the line guy if he filled the tanks to the tabs in the morning like he usually does in the summer. He says he did. So fuel to the tabs, and just 0.2 burned off, should be simple to verify. I preflight and look in the tanks and something doesn't seem right. Now I start looking at the Hobbs to verify and see 0.2. Now I might verify against the tach...hmm...tach shows 2.5 gone? Now I might get the line guy over to figure this out. And that's when we start talking about the previous renter.
 
RalphInCA said:
Yep, I sure am. It's annoying

I got in trouble once for sitting in the airplane and fooling around with the Garmin 430, trying to figure it out. Without knowing it I ran up the Hobbs.
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In trouble from whom, the owner? If you're paying for the hobbs set up to the master switch instead of the oil pressure then I would imagine that it would be more money in the owner's pocket.
 
Our school records the Hobbs and tach each flight. You might fool them for a tenth or two, but anything more than that I'm pretty sure you would have some explaining to do.
 
Put me on the list of let the content of your character be your guide. Many rental airplanes help with that by being "hot wired" and run through an oil pressure switch. No oil pressure, no tic toc. On these you can turn on the master to check lights, flaps, radios and stuff and the Hobbs won't turn because the engine ain't makin oil pressure. Want some free time in the air? Go ahead, turn the engine off. Oh yeah, don't rent to Glider pilots on "good air" days.
[edit]. Some responses to this post have made realize it may have been misinterpreted. I in no way suggest to shut down the engine to save a few bucks. "Go ahead, turn the engine off" was meant as shutting the engine down was the last thing anyone would actually do.
 
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RalphInCA said:
Hmmm.

So, what I should do is climb at Vy, to about 10k, shut off the master and shut the engine off and glide. Then I can fly for free.

That conscience thing will be a little tougher...
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Most people with curiosity have thought of this at some point most likely. The vast majority are smart enough to let it end with the thought. The Golden Rule is still a good way to live. Don't mess with my airplane like you wouldn't want me to mess with yours.
 
Matthew said:
So I go rent the plane. I check the book and see it last flew 0.2 and that was the first flight of the day, I'm next. On the way out the door I ask the line guy if he filled the tanks to the tabs in the morning like he usually does in the summer. He says he did. So fuel to the tabs, and just 0.2 burned off, should be simple to verify. I preflight and look in the tanks and something doesn't seem right. Now I start looking at the Hobbs to verify and see 0.2. Now I might verify against the tach...hmm...tach shows 2.5 gone? Now I might get the line guy over to figure this out. And that's when we start talking about the previous renter.
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... ok, I'm back.

Now we start talking about the previous renter. Did the Hobbs fail? I know it's my dream scenario for an instrument failure. Did he just transpose a couple numbers and forget to carry the one?

Now I'm getting mad because this is costing me time. We fuel back to the tabs and notice around 25 gal went in...hmmm, 10 gph and 25 gal is around 2.5 hrs. Pretty close to what the tach said. Curiouser, and now I'm late for my flight and thinking, "why me?" Maybe it's an honest mistake. If so, then the honest guy ahead of me won't gripe when I make a note to the FBO about the discrepancy. If it's not an honest mistake, then the FBO will at least appreciate me pointing out the discrepancy. Either way, I'd let the FBO know something was up so I don't get billed for the extra fuel that I had to go out of my way to put into the tanks.
 
Or. On my 172L, the Hobbs fuse and the clock fuse are the same - very easy to pull. And dumb and wrong. Please don't.
 
My Hobbs is activated by an oil pressure switch. Engine comes on, Hobbs is running. Electrically powered Hobbs meters are for fools! =D
 
Before we had a better tracking system people use to unplug the Hobbs meter. Do a lap in the pattern, pop the cowl, unplug the Hobbs, and go out to eat somewhere. On the trip back land short, pop the cowl, plug the Hobbs back in, and go home.
 
ARFlyer said:
Before we had a better tracking system people use to unplug the Hobbs meter. Do a lap in the pattern, pop the cowl, unplug the Hobbs, and go out to eat somewhere. On the trip back land short, pop the cowl, plug the Hobbs back in, and go home.
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What year was this? Perhaps I'm not as old as you but this was not in our repertoire.
 
Shucks.... I started in the 80's. Never heard of this.
 
Timbeck2 said:
In trouble from whom, the owner? If you're paying for the hobbs set up to the master switch instead of the oil pressure then I would imagine that it would be more money in the owner's pocket.
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Nobody else was using the airplane, so I figured I would get myself more familiar with the 430. So I turned on the master and fired up the 430. Didn't know this was going to start the Hobbs. Made sure all other electrical power users were off (except the TC - no way to turn that off) and played around for 15 minutes or so. Shut everything down and went my merry way, much smarter about the 430.

Was informed by the Flying Club manager the next day that what I did kinda messed up their accounting a little. They didn't charge me, but it was implied that they could have.

Lesson learned.
 
ircphoenix said:
My Hobbs is activated by an oil pressure switch. Engine comes on, Hobbs is running. Electrically powered Hobbs meters are for fools! =D
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Well, every airplane in our Flying Club (I think we have 7) is set up this way. Not sure why. I doubt it's going to change.

JUST TO BE CLEAR FOLKS: Since I suspect other members of my Flying Club are on this board, and since aviation is a small community, my pondering on this subject was just that - pondering. A thought exercise. I'm happy to pay to support my flying addiction.

And, to paraphrase another post in this thread I religiously follow the golden rule for renters: "Do onto other renters as you would have them do unto you."
 
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One possibility not mentioned is the alternator or generator that might have some issues with the surge when you switch the master off and on. If you're not concerened about theft of time maybe you'll think about what happens if the power supply for instruments quits on a flight.....?

Frank
 
RalphInCA said:
Hmmm.

So, what I should do is climb at Vy, to about 10k, shut off the master and shut the engine off and glide. Then I can fly for free.

That conscience thing will be a little tougher...
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The engine still makes oil pressure and spins the tach when it windmills. It has no idea if fuel or slipstream makes the crankshaft turn.

As for the conscience thing, we rely on that for a lot. Have you noticed how poor the physical security of a tied down aircraft is? And a padlock on a hangar door is not particularly daunting.
 
RalphInCA said:
The Hobbs on the airplanes I fly activate when the master is turned on.

If I turned the master switch off during flight, this should stop the Hobbs, right?

If I'm in an area where I will not need the radios, what's to stop me from turning off the master to stop the Hobbs and fly for free?
Click to expand...

If you don't Hobbs it you can't log it.
 
Of find which breaker goes to the Hobbs

Ether way you'd be a scum bag theif, and it wouldn't take too long for the FBO to catch on, with aviation being he small community it is, I'd wager itd be cheaper and easier to just pay the Hobbs be getting black balled in your GA community.
 
Lachlan said:
If you don't Hobbs it you can't log it.
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In that case a have a few thousands hours I need to delete, actually I'm pulling the Hobbs out of my 185 next annual, no need, and who the heck rents a 185 out anyways.
 
I would think this would violate some FAA regulation, especially in a rental. No different than messing with the odometer.
 
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