Fooling hobbs, logging full time

I thought ALL Hobbs ran off the oil pressure switch. Maybe that's not true but because of that perception I suspected a troll at post #1. Are there some that use the master for power?
That oil pressure switch setup is not cheap. The tee fitting that Cessna uses at the firewall to mount the switch in the oil pressure gauge line is expensive. If this stuff wears out, mechanics are tempted to just connect the Hobbs to the master contactor's bus side. The tee is around $300, the switch $50 or $60 or more. If you can find these parts.
 
Evector I flew had it off the master. CFI knew of course and made sure to keep it off until we were ready to go.
 
I thought ALL Hobbs ran off the oil pressure switch. Maybe that's not true but because of that perception I suspected a troll at post #1. Are there some that use the master for power?
I have rented a lot of 172s over the years, but there is only one that I rented for a while whose Hobbs ran whenever the master switch was on.
 
Fraud like this, if done by enough thieves, causes the airplane to run well past scheduled inspections and AD compliance times. It also raises the costs for all the honest renters: more fuel and oil burned, more wear on components that then need replacing unusually "early."
Service is usually done based on tach time, not Hobbs.
 
They can't contest the entries in your logbook AFAIK.

If he is in training, the CFI/chief pilot can certainly require you to void log entries as they will ultimately approve him taking the check ride.
I don’t think that’s unreasonable.
 
If he is in training, the CFI/chief pilot can certainly require you to void log entries as they will ultimately approve him taking the check ride.
I don’t think that’s unreasonable.
Maybe in 141, I don’t know about that one, but certainly not in 61
 
Just use tach hours in the future, much easier.
One assumes that the aircraft has a recording tach. Not all do.
I thought ALL Hobbs ran off the oil pressure switch.
Nope. And not all aircraft have a Hobbs.

At one time it was not uncommon for an aircraft to have neither a recording tach or a hobbs. One had to keep track of time with one's watch and write it in the log book.
 
Wow, This seems like a troll post? Guest poster?
The flight school I attended used hobbs time for billing FWIW.
I would have never thought of something like this when I was renting. It is not hard for the chief flight instructor to figure out you were stealing from the flight school. I think you need to move on from aviation and do something else in life that does not involve stealing. Wow oh wow.
 
Willing to bet OP stole a ton of time. You don’t quibble like this over a few hours. Wonder what they use to calculate the 100 hour mx?? Put the slight school at risk and other renters.
How can they prove the flight time they logged??
 
I thought ALL Hobbs ran off the oil pressure switch. Maybe that's not true but because of that perception I suspected a troll at post #1. Are there some that use the master for power?

A Hobbs meter is simply an hour meter that runs whenever power is applied to it. That power can be supplied any way you like.

Commonly, it's on an oil pressure switch.
Also commonly, it's on a weight-on-wheels switch.
I used to own an airplane with it on the master switch, because that's how some previous owner wanted it.
 
Back when I was actively instructing many years ago there were a few CFIs or renters that pulled a circuit breaker to keep the “meter” from running (and it did stop it from running). A little here a little there. Wasn’t right back then, and it still isn’t. Difference today is there isn’t much shame when getting caught. It’s “oops, I shouldn’t have, no big deal, can we move on?”.

Is this the same OP troll that had another “oops, I got caught” moment? If not, and this real, I’d say you should reimburse the school and be terminated from training there.

This line, in light of what you did, is so ridiculous.

Let me begin by stating that I really try to do what’s right, but in these uncertain economic conditions, saving money is crucial.
 
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They are not using tach Time?

Seems that charging hobbs time is also being crooked, so maybe you two deserve each other.
Everywhere I have rented used Hobbs. But I agree with you, I wish they all used Tach time. With Hobbs I'm not incentivized to treat the airplane right, start up on a cold day and go full throttle until the destination. Since Tach is run off of the RPM's, I can sit and idle to warm up the engine and not get charged an arm and a leg. If I were king for a day, charging by Tach would be mandatory.

Now that I'm an owner I don't care, hell my plane doesn't even have a hobbs, unnecessary weight & complexity.
 
...This line, in light of what you did, is so ridiculous.

Let me begin by stating that I really try to do what’s right, but in these uncertain economic conditions, saving money is crucial.

I'm reminded of this:

do-or-do-not.jpg
 
I was practicing nocturnal habits while on the job when an anvil fell on my head. Now the boss wants me to erase my log book and to not come around anymore....
 
Everywhere I have rented used Hobbs. But I agree with you, I wish they all used Tach time. With Hobbs I'm not incentivized to treat the airplane right, start up on a cold day and go full throttle until the destination. Since Tach is run off of the RPM's, I can sit and idle to warm up the engine and not get charged an arm and a leg. If I were king for a day, charging by Tach would be mandatory.

Now that I'm an owner I don't care, hell my plane doesn't even have a hobbs, unnecessary weight & complexity.

My plane, and the plane I used to instruct in, don't have hobbs either.

Seems to me that a student pilot really doesn't have the flight time they claim to, when going up for the flight test.
I frequently turn on the master power switch, the radio tuned to the local channel, flip it to overhead speaker, leave the doors open, and do my walk around, that way I can listen to local traffic, and know what traffic is in the area for me to be aware of. So my hobbs would run for 15 minutes before engine start.
 
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If the OP is looking to make a career as a pilot, this situation may follow him.

FAR 61.153 Eligibility Requirements
(c) Be of good moral character.

Intentionally defrauding your flight school I say would speak to your moral character. The aviation community is by and large built on trust. Trust that your logbook isn't forged. Trust that you won't fly under the influence of unapproved medications. Trust that you are properly pre-flighting and operating the aircraft. You have a record now of betraying that trust. How can the FAA, a potential employer, or future passenger, trust you?
 
If the OP is looking to make a career as a pilot, this situation may follow him.

FAR 61.153 Eligibility Requirements
(c) Be of good moral character.

Intentionally defrauding your flight school I say would speak to your moral character. The aviation community is by and large built on trust. Trust that your logbook isn't forged. Trust that you won't fly under the influence of unapproved medications. Trust that you are properly pre-flighting and operating the aircraft. You have a record now of betraying that trust. How can the FAA, a potential employer, or future passenger, trust you?
That's been a Hallmark for self-righteous people for decades. But has that reg ever *actually* been enacted to prevent an ATP?
 
LOL

I'm renting wet at the moment and on a cross country recently my instructor told me to bring the RPM's back a bit for efficiency and engine life. I chuckled and said "not my fuel not my engine I'm paying by the hour, I'm good"
This is just next level
 
LOL

I'm renting wet at the moment and on a cross country recently my instructor told me to bring the RPM's back a bit for efficiency and engine life. I chuckled and said "not my fuel not my engine I'm paying by the hour, I'm good"
This is just next level

Probably also means improper warm ups at times, fast taxi speeds, ultra quick run ups, and more, being done by rookies, which sure doesn't help with safety. The mere idea strikes me as unethical and immoral.
 
LOL

I'm renting wet at the moment and on a cross country recently my instructor told me to bring the RPM's back a bit for efficiency and engine life. I chuckled and said "not my fuel not my engine I'm paying by the hour, I'm good"
This is just next level
Haha! The instructor doesn’t care, it’s not on his dime. I agree that charging Hobbs time doesn’t encourage renters to treat the airplane with kindness. Tach should be the standard.
 
I'm actually surprised that a lot more students do not buy their own planes. If 3 to 5 students were to buy say a 172 together, it would be better than renting IMHO.
I bought myself a Warrior for training on, and am so glad I did.
 
The digital tachs, once getting above a predetermined engine speed (just above idle) almost match the oil pressure triggered hobbs when the flight is complete, but the old style tachs are usually reading less, a bunch when doing touch and goes or full stops and taxi backs.
 
Probably also means improper warm ups at times, fast taxi speeds, ultra quick run ups, and more, being done by rookies, which sure doesn't help with safety. The mere idea strikes me as unethical and immoral.
Sticking fuel tanks to determine fuel quantity strikes you as unethical and immoral. ;)
 
I'm actually surprised that a lot more students do not buy their own planes. If 3 to 5 students were to buy say a 172 together, it would be better than renting IMHO.
I bought myself a Warrior for training on, and am so glad I did.

The only reason I wouldn’t do it today if I were learning is to avoid exposing myself to the risk of an unexpected high cost maintenance event during the training period. But, I’ve known plenty of people that have done this. If a student is going to own one after getting their ticket, it’s a great way to dive in early.
 
Probably also means improper warm ups at times, fast taxi speeds, ultra quick run ups, and more, being done by rookies, which sure doesn't help with safety. The mere idea strikes me as unethical and immoral.

Curious if you mean running a rental harder than you'd run your own or are talking about the OP?
 
I posted awhile back and now I’m back again.

Let me begin by stating that I really try to do what’s right, but in these uncertain economic conditions, saving money is crucial. Over the past few weeks I’ve been renting some airplanes from a local outfit and fooling the hobbs meter so to speak by turning off the master when I can do so in airspace that doesn’t permit radio or ADSB. My goal was to try and stretch my dollar as far as possible. Fly a few hours, get billed for part of it and log all of it.

Well, needless to say I got found out by our chief pilot who put two and two together in ways that I didn’t think would get caught. I admittedly messed up, yes, I really screwed the pooch. I have no problem saying so. My problem now, and what isn’t fair to me, is that the school is trying to get me to erase the time in my logbook that I logged and didn’t pay for even though in reality I actually flew what I logged. Is this legal to even ask for? If I legit flew the time, I should be able to log it. I told the school I would gladly pay for the discrepancy of time not billed for and I’m going to, but they’re kicking me out and not letting me rent from them any longer. They also said to expect a letter and call from the flight standards office but I don’t see that what I did was a rule violation so I don’t understand what the FAA can do. Be kind, but please advise how this will turn out and what I should do now?

Maybe while you are out flying the FBO should just increase the plane rental to $750 a hour a tach hour.
 
Generally tachs run 30% "slower" than a hobbs.

The planes cost what they cost, so a flight school billing on tach loses to the flight school billing on hobbs, because that school will be able to appear 30% cheaper. Thus, all schools end up on hobbs.
 
Many years ago when my buddy and I were broke 20 yo private pilots, we rented a "new" plane that was just added to the line. When I say new, it was a mid seventies 172 like the rest, but new to us and had something high tech, like DME.

Nevertheless, I remember preflighting the plane and looking over and noticing that the Hobbs ticked up while we had the master on to drop the flaps. we got the same crazy idea as the OP that we could just turn the master off in flight and save rental costs.

So we took the plane up in our cross country and once at cruise altitude we shut down the master. That lasted all of about 45 seconds before we decided that the odd silence of no radio, no intercom, and not to mention no navigation instruments made it a not very pleasant experience. We were also bright enough to know that if we turned the plane in with less Hobbs time than tach that the FBO would figure out something was fishy pretty quick.

Out takeaway from that lesson was to not leave the master switch on for long periods of time on the ground. Good for our wallets and good for the owner's battery.
 
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