logging time

[airway]

If you don't want any questions from Transport, or your Boss, you need to write down 4 times on every flight.

1. The moment the aircraft first moves under its own power for the purpose of taking off.
2. The moment the aircraft leaves the supporting surface.
3. The moment the aircraft touches the supporting surface at the next point of landing.
4. The moment it comes to rest at the end of the flight.


Hobbs or tach time will not give you exact flight times and may not be calibrated properly.

It is especially important to get exact Air Times, as maintanence costs go up for every extra minute you add on to Air Time.

If you taxi and don't take off, do not enter anything in any logbook.

Transport has said that Touch and Go's at the same airport may be entered on one line in a Log Book.





From the AIM:

4.1 Air Time and Flight Time
Air Time is the period of time commencing when the aircraft leaves the supporting surface and terminating when it touches the supporting surface at the next point of landing.

Flight Time is the total time from the moment an aircraft first moves under its own power for the purpose of taking off until the moment it comes to rest at the end of the flight. This should be recorded in all Pilot Log Books.

NOTE: Air Time and Flight Time should be recorded to the nearest 5 minutes, or to the nearest 6 minutes when using the decimal system as follows:

0 to 02 = .0
03 to 08 = .1
09 to 14 = .2

15 to 20 = .3
21 to 26 = .4
27 to 32 = .5

33 to 38 = .6
39 to 44 = .7
45 to 50 = .8

51 to 56 = .9
57 to 60 = 1.0

[Flaperons]

Flight Time: the time from when the aircraft starts moving for the purpose of takeoff until it stops moving after landing. In other words, chocks to chocks. However, in terms of logging at a flight school (or anywhere, for that matter), your logbook needs to match the company flight sheet/tech log. So whatever the school charges you for, Hobbes or not, that is what you log.

Air time: Takeoff to touchdown. This is the one you don't @#$! around with. Use your watch. No Tach; no -0.2 or whatever. Maintenance is based on airtime, so keep it correct. If the school tells you to take flight time and minus a certain amount, tell them to go @#$! themselves. Skimping on airtime over several years could result in several maintenance cycles being skipped. UNSAFE.

[airway]

Flight Time: the time from when the aircraft starts moving for the purpose of takeoff until it stops moving after landing. In other words, chocks to chocks. However, in terms of logging at a flight school (or anywhere, for that matter), your logbook needs to match the company flight sheet/tech log. So whatever the school charges you for, Hobbes or not, that is what you log.

Don't shoot the messenger, but if your flight school/company is using hobbes/tach times for flight time, they are disregarding the CARS and the AIM. Flight time could average .1 less than the hobbes time on every flight.

From the CARS:

"flight time" - means the time from the moment an aircraft first moves under its own power for the purpose of taking off until the moment it comes to rest at the end of the flight; (temps de vol)

[Hedley]

if your flight school/company is using hobbes/tach times for flight time, they are disregarding the CARS and the AIM

I guess Transport, when they find out about this earth-shattering
news, will shut down every FTU in the country, to avoid such
blatant CARs contraventions!!

P.S. I add use tach time for air time. I add 0.2 to it to calculate
flight time. So does everyone else I know. I have been doing so
since before you were born. Feel free to drop a dime to Enforcement
on all of us.

[airway]

Hedley,

I am well aware of how FTU's charge their students. By using hobbes time they may get an extra .1 of billable time out of every flight.

I was merely pointing out the regulation as it stands now. It may have been different in the past.

I realize that this Flight time/ Hobbes time issue is a minor point, and transport probably doesn't care which method you use, but for myself, I try to comply with the CAR's as closely as possible, as long as they are the safest option for the particular situation I am in.

[small penguin]

Since maintenance on an aircraft is on an airtime basis, that a school/club charge hobbs or flight time, they still have the upper hand.

Nothing like doing a 1.5hour flight time, 0.9 hour air time flight, and being charged about 200 dollars. Yup.

[airway]

P.S. I add use tach time for air time. I add 0.2 to it to calculate
flight time. So does everyone else I know. I have been doing so
since before you were born. Feel free to drop a dime to Enforcement
on all of us.

Correct me if i'm wrong, but if your tach time starts when your engine starts, tach time will be closer to flight time, not air time.

[Big Pistons Forever]

The tach hour meter is a revolution counter designed so that cruise RPM is converted into hours and tenths. Therefore At full RPM the timer runs fast but when the engine is at idle RPM it only shows about 30 % of real time. The theory is over the course of an average flight tach time will give a reasonable approximation of airtime. In the US where a flight by flight journey log style document is not required for private aircraft, Tach time is used to for the scheduling of periodic inspectons (like the 100hr) or AD's which have an airtime component.

[Hedley]

Correct me if i'm wrong

Yes, you are wrong. Tach time is only the same
as your wristwatch time at 2400 rpm. It is
perfect for air time because of this.

And a flight time of 0.2 more than tach time is
completely acceptable for pilot logging purposes.

You don't have to believe me, though - I'm just
an Authorized Person. Are you?

[joco]

When I did my PPL the CFI mentioned that the school was looking at a 1 hr flight as in 1.0 flight time and 0.7 airtime. His explanation was that until you start, do your checks, talk to ground, taxi, do your run-up, have the engine warmed up a bit, that would be 0.2 before take-off. After landing, you would have about 0.1 for touch-down, taxi and shutdown on the apron.

All this in CYHM.

[airway]

Yes, you are wrong. Tach time is only the same
as your wristwatch time at 2400 rpm. It is
perfect for air time because of this.

And a flight time of 0.2 more than tach time is
completely acceptable for pilot logging purposes.

You don't have to believe me, though - I'm just
an Authorized Person. Are you?

OK, you got me on the tach time thing. I couldn't remember how they work. I have not flown a plane with one for 10 years.

Used to be a Class 1 instructor, CFI, DFTE, and an authorized person at a FTU. We used the 4 times outlined in the AIM and the CAR's. Most other schools in the area used Hobbs time for flight time. No school used tach time.

After doing some research, I see that tach time is calibrated for different rpms for different engines. Examples I have seen have been between 2300 and 2500 RPM's.

[tcraft]

So,what we`re saying is ,that at 2400rpm one can add a .2 to the tach time. I have two engines at 1850rpm each, what do I log? .4,.6,.8 ?

[airway]

Tach time will give you an estimate of air time and flight time. The accuracy of this method depends on many things. A few I can think of right now are:

1. Delays during taxi in or out.
2. length of flight.
3. RPM settings during the flight. A long cross country flight at the calibrated RPM setting will be more accurate than a short aerobatic flight.

If you want exact air and flight times, you have to use your watch.

[Big Pistons Forever]

I got my CPL students to always write down the roll,up,down,and stop times even though the school used hobbs time. I did this to get them into the habit of noting the time because that is what they will be expected to do when they get a line flying job.