Where's Hobbs?

The ramblings of our community of aviators.

Moderators: Rick, Lance Murray

Post Reply
User avatar
Soareyes
3 Diamonds Member
3 Diamonds Member
FIRST NAME: Dan
Aircraft: DA42-VI
Registration: N518R
Airport: KINF

Posts: 51
Joined: Fri Feb 28, 2020 12:47 pm
Has thanked: 25 times
Been thanked: 31 times

Where's Hobbs?

Post by Soareyes »

It always seemed a bit like cheating to count pilot hours based on the Hobbs meter. Why get flying credit for sitting on the ramp waiting for the engine to warm up?

It always seemed a bit incorrect to base engine maintenance on tach time only over a certain rpm or flight time only above a certain airspeed. Sure, idling on the ground is less stressful on the engine than flying but even at idle the engine is running and parts are slowly wearing out.

When you think about it, it really should be the other way around, flight time for the pilot and Hobbs time for the airplane.

At the end of my first day of transition training I looked all over - Haha, the joke’s on me. The new DA42 doesn’t even have a Hobbs meter. Good, shouldn’t count anything but flight time in the logbook anyway.

But…, now there’s this apples and oranges thing. Even if Hobbs time is not the pilot’s true flight time it is a widespread, understood, agreed upon standard. Kind of like how we fly altitudes based on barometric pressure instead of actual GPS altitude. We are all using the same frame of reference.

Operating the airplane on the ground with, “the intention to fly” as they say, requires some skill and should get a measure of credit.

Now my logbooks will have a combination of Hobbs time and flight time. It will look like I don’t fly as much. It will take longer to build hours to show the insurance company why they should lower my rates.

I don’t care enough to add a Hobbs meter to the plane but I may use a timer and record that in the logbook. Anybody else do that?
DA42-V1

Previous: Hang glider, Paraglider, DA40x3, Cessna 150 Aerobat, SR22
User avatar
CFIDave
5 Diamonds Member
5 Diamonds Member
FIRST NAME: Dave
Aircraft: DA62
Registration: N62DV
Airport: KJYO

Posts: 1972
Joined: Wed Nov 07, 2012 3:40 pm
Has thanked: 114 times
Been thanked: 722 times

Re: Where's Hobbs?

Post by CFIDave »

Dan:
When my new DA42-VI was built by the Austrian factory it had no Hobbs meter, so the Canadian Diamond factory installed one before I took delivery (I didn't even need to ask). However my DA62 lacks a Hobbs meter, because DA62s are not expected to be used for flight training.

But even without a Hobbs meter you still have two other ways to monitor time for your pilot logbook, both of which I use with my DA62:

1. Stick an SDcard into the top MFD slot, and your plane will automatically generate a log file per flight. You can then upload these files to one of many websites that will automatically calculate and display both your Hobbs and "tach" (G1000 total time in service corresponding to "wheels up" airborne) hours. Hobbs time technically shouldn't start until the aircraft starts moving for taxi, but G1000 operating time is a close enough approximation.

2. If you don't want to bother with an SDcard, you can always use your watch and write down start and end times.
N62DV DA62 62.056
N42DA DA42-VI 42.N117 (sold)
N811ET DA40 XLS 40.874 (sold)
KJYO Leesburg, Virginia
User avatar
Davestation
3 Diamonds Member
3 Diamonds Member
FIRST NAME: David
Aircraft: D-JET
Registration: NDJET
Airport: KFTW

Posts: 136
Joined: Tue Mar 12, 2019 7:49 pm
Has thanked: 58 times
Been thanked: 36 times

Re: Where's Hobbs?

Post by Davestation »

I don’t know about the hobbs being universal, my experience has been mostly with going off of the engine tach for maintenance. I’d say if anything those are actually more forgiving than the Garmin tach because they are more like a car odometer and vary with RPM whereas the former is just a clock so it’s barely even moving on the ground. Going off the hobbs would be unpleasant; seems like the Garmin is somewhat of a happy medium.
User avatar
Boatguy
4 Diamonds Member
4 Diamonds Member
FIRST NAME: Russ
Aircraft: DA40NG
Registration: N454M
Airport: O69

Posts: 451
Joined: Mon Jan 22, 2018 4:48 am
Has thanked: 188 times
Been thanked: 326 times

Re: Where's Hobbs?

Post by Boatguy »

I think runway excursions / incursions, and pilots hitting fixed objects while taxiing justifies the Hobbs for "flight" time. The engine is running and you are in control of the machine.

The service time on the Austro engines only tracks air time. Taxi time is essentially no load on the engine, so why have to pay for maintenance with something that isn't causing engine wear?
User avatar
DaveS1900
2 Diamonds Member
2 Diamonds Member
FIRST NAME: Dave
Aircraft: DA40
Registration: N521DD
Airport: I74 Urbana Ohio

Posts: 28
Joined: Sun May 06, 2018 1:09 am
Been thanked: 7 times

Re: Where's Hobbs?

Post by DaveS1900 »

Over 30+ years of flying I have used about everything. So I guess I am in the same boat or (airplane).

Considering time on the ground-- getting a clearance, start-up looking for engine problems, taxiing with other airplanes, running checklists, and following tower directions especially at a busy airport can be a stressful time which requires brain power. But, cruising along with the autopilot "on" while eating a sandwich and talking to your wife about the beach, gets counted with no question.

Dave S.
Ohio
User avatar
gtmize
3 Diamonds Member
3 Diamonds Member
FIRST NAME: gary
Aircraft: DA40
Registration: N175DA
Airport: KFMN

Posts: 69
Joined: Sat Apr 01, 2017 6:58 pm
Has thanked: 3 times
Been thanked: 12 times

Re: Where's Hobbs?

Post by gtmize »

CFIDave wrote:
Sat Aug 29, 2020 4:44 pm
Dan:

1. Stick an SDcard into the top MFD slot, and your plane will automatically generate a log file per flight. You can then upload these files to one of many websites that will automatically calculate and display both your Hobbs and "tach" (G1000 total time in service corresponding to "wheels up" airborne) hours. Hobbs time technically shouldn't start until the aircraft starts moving for taxi, but G1000 operating time is a close enough approximation.

-----------------------------------------------------------------
Are you uploading to Foreflight to Track Logs ... in addition to log time it seems a good way to monitor engine performance for you Annuals
User avatar
Soareyes
3 Diamonds Member
3 Diamonds Member
FIRST NAME: Dan
Aircraft: DA42-VI
Registration: N518R
Airport: KINF

Posts: 51
Joined: Fri Feb 28, 2020 12:47 pm
Has thanked: 25 times
Been thanked: 31 times

Re: Where's Hobbs?

Post by Soareyes »

Thanks for the suggestion to let ForeFlight log the time. To my shame perhaps I barely use ForeFlight for much more than a moving map and approach plates.

Extremely low tech, but for now I am keeping a little moleskine book in the plane to jot down the starting and ending times so I can later write the time in a hardcover logbook.

Someday in the nursing home I am going to have my logbooks lined up on the shelf, a tangible reminder that there was a time when I could fly through the air. Maybe I'll take one down now and then, leaf through and remember when. I will probably have forgotten my ForeFlight password by then. Hmm, now where did I write it down?
DA42-V1

Previous: Hang glider, Paraglider, DA40x3, Cessna 150 Aerobat, SR22
Post Reply