Tach time vs clock time

texasag93

texasag93

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texasag93
I fly a 182. We are charged by tach time.

Today I flew for 50 minutes and only 4/10 of an hour was on the tach. I was only doing pattern work for cross winds.

Do I record the 4/10 (.4) or the 50 minutes (.8 or .9) in my log book?

I was alone and have my PP ASEL. It is PIC time either way.
 
texasag93 said:
I fly a 182. We are charged by tach time.

Today I flew for 50 minutes and only 4/10 of an hour was on the tach. I was only doing pattern work for cross winds.

Do I record the 4/10 (.4) or the 50 minutes (.8 or .9) in my log book?

I was alone and have my PP ASEL. It is PIC time either way.
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It is your log book. Either number is legit.
 
Easy enough, log the elapsed time.

PIC time has nothing to do with tachometer time.
 
I believe its only for charging purposes (tach), just going out on a limb here but you should record the 50 minutes.
 
Tach time I believe in most planes is based on revolutions of the prop. It is a derived number and is not a true time of flight. Hobbs time is a true number based on time(though from what I read in a previous thread the start and end of the hobbs counting may differ in different planes). Anyhow it is based on actual hours and fractions of hours. All of my training charges and renting charges, as well as times have been based on hobbs and not tach(which has always been a smaller number). I use hobbs time for my log book, and tach time for engine issues.

Doug
 
PIC time starts when the airplane moves under power for the purpose of flight, until it stops and shuts down at destination.

Aircraft time and PIC time are different things, defined differently by the regs. Your watch always reflects PIC time.

Tach time only exists for the purpose of aircraft and engine time in service, and has
nothing whatsoever to do with PIC time.
In my plane, the electronic tach does not start recording until RPMs reach 1200, so startup and taxi time do not show up in tach time. But all that time does count as PIC time.

Tach time is merely one way of recording airframe time. You can also a have a hour meter that starts recording when the aircraft leave the ground (with squat switches), or when the gear comes up.
 
PilotAlan said:
PIC time starts when the airplane moves under power for the purpose of flight, until it stops and shuts down at destination.

Aircraft time and PIC time are different things, defined differently by the regs. Your watch always reflects PIC time.

Tach time only exists for the purpose of aircraft and engine time in service, and has
nothing whatsoever to do with PIC time.
In my plane, the electronic tach does not start recording until RPMs reach 1200, so startup and taxi time do not show up in tach time. But all that time does count as PIC time.

Tach time is merely one way of recording airframe time. You can also a have a hour meter that starts recording when the aircraft leave the ground (with squat switches), or when the gear comes up.
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I really like this way of explaining it. :yes:
 
I also pay by tach time flying the DA40 with the VM1000 engine monitor. The operating manual says "engine hours are accumulated anytime RPM is greater than 1500." Does this mean that everything above 1500RPM is counted in actual time and nothing below 1500RPM is counted at all? Others says this is not the case but on a recent flight with cruise RPM @2000 and climb power @2400 I logged 1.5 tach and 1.7 Hobbs. With an analog tach, this setup would yield a much lower tach time. Can anyone confirm if my suspicions with the engine monitor tach time are correct?
 
Tach time and when it is recorded is an empirical number set by the engine manufacturer based on experience and some ignorance and superstition, just like TBO. Maintenance requirements are based on that time and it has nothing to do with PIC time.

Log your time based on the Hobbs or your watch. I use the Hobbs which is the simplest for me, even if I am warming the engine up on a really cold day since who knows if it will jump the chocks and I will have to do some pilot type stuff.;)
 
Definitely use the Hobbs.
An example: If you were Enroute, and that flight portion was an hour long, your tach time may only be 75% of that depending on your power setting. The actual time you were flying is an hour long.
 
Do not put tach time in your logbook, you will short change yourself. If you dont remember to look at your actual block in and block out times, you can just take the tach, multiply it by 1.2 and that will give you a pretty darn accurate hobbs time.
 
Inverted said:
Do not put tach time in your logbook, you will short change yourself. If you dont remember to look at your actual block in and block out times, you can just take the tach, multiply it by 1.2 and that will give you a pretty darn accurate hobbs time.
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Unless, of course, you want to simplify things. I have not kept track of Hobbs time in the last 11 years (and 1,200 hours of Tach time!). I don't need hours to impress anyone, and I don't need any more time to obtain any more ratings.

I keep a folding aluminum clipboard in the plane, on which I log Tach time for each flight flown, as well as oil added, etc. About four times a year I take this clipboard home and transfer the info into my pilot log book. Keeping separate records for the pilot and the plane seemed superfluous and arduous after the first couple of years of ownership.

Wells
 
W. Stewart said:
Unless, of course, you want to simplify things. I have not kept track of Hobbs time in the last 11 years (and 1,200 hours of Tach time!). I don't need hours to impress anyone, and I don't need any more time to obtain any more ratings.
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I don't take the idea of putting tach time in a pilot logbook to reflect flight hours as simplifying things. I take it as shortchanging and inaccurate. It isn't about impressing anyone, its about recording the correct time in the correct logbook. You wouldn't use hobbs time to overhaul an engine, so why use tach time to record pilot flight hours?
 
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Inverted said:
I don't take the idea of putting tach time in a pilot logbook to reflect flight hours as simplifying things. I take it as shortchanging and inaccurate. It isn't about impressing anyone, its about recording the correct time in the correct logbook. You wouldn't use hobbs time to overhaul an engine, so why use tach time to record pilot flight hours?
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:yes: The FAR uses the word SHALL regarding recording of pilot logbook entries. Although I don't understand the legal reason why it's compulsory, if I were in his shoes, I'd use actual time as I do now. My mantra is: 'The flight's not done until the paperwork is finished'.
 
If the flight wasn't done until the paperwork was done I would have quadruple the time I have now. Logbook time should reflect the time in which the aircraft is moving under its own power for the purpose of flight, which without looking at the FARs, is pretty close to what it says in there. Tach time is not an accurate reflection of time unless you spend the entire flight from startup to shutdown at full power.
 
DanielH said:
I also pay by tach time flying the DA40 with the VM1000 engine monitor. The operating manual says "engine hours are accumulated anytime RPM is greater than 1500." Does this mean that everything above 1500RPM is counted in actual time and nothing below 1500RPM is counted at all?
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I believe so. On the G1000 DA40, the time on the engine page is flight time, and I've taxied it around on the ground and accumulated nothing at all, and I've flown for an hour at both 2400 and 2100/2200 RPM, both of which resulted in exactly 1.0 - So that, at least, is an "all or nothing" gauge, and I believe the VM1000 is the same, especially if that's what the operating manual says.

Others says this is not the case
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They are probably familiar with plain old analog tachs and didn't read the manual the way you did...
 
Inverted said:
If the flight wasn't done until the paperwork was done I would have quadruple the time I have now. Logbook time should reflect the time in which the aircraft is moving under its own power for the purpose of flight, which without looking at the FARs, is pretty close to what it says in there. Tach time is not an accurate reflection of time unless you spend the entire flight from startup to shutdown at full power.
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You cannot count the time between aircraft end of movement and ink flowing. That would not be legal or consistent with what I meant.
 
My question was tach time vs clock time, not PIC v BIC time.....:goofy:
 
Log off of your watch. Bill off of the tach. Be happy you got a good deal going with the club (over what the other guy on the field does :rolleyes: )
 
Jaybird180 said:
The FAR uses the word SHALL regarding recording of pilot logbook entries. Although I don't understand the legal reason why it's compulsory,
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Actually, the word is MUST, if you're speaking of 61.51, and the beginning of that rule begins with "for meeting certification requirements and recency of experience".

If you are not using the time for that purpose, log it any way you want.
 
I write down the engine start/shutdown times on each leg for the purpose of logging flight time. The plane I fly doesn't have a Hobbs meter.
 
nosehair said:
Actually, the word is MUST, if you're speaking of 61.51, and the beginning of that rule begins with "for meeting certification requirements and recency of experience".

If you are not using the time for that purpose, log it any way you want.
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I stand corrected. It's much easier to look up the reg sometimes rather than recite from memory....:mad2:
 
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