Use Hobbs time for OUT/IN

Craig Rairdin

New member
Apr 4, 2004
This is so simple I'm probably just overlooking it. This program seems so complete I can't believe this feature has been overlooked, given that it's the standard way that both students and owner/pilots calculate flight time...

How do I enter my OUT and IN times as "Hobbs" time (ie. 3426.7 to 3428.1) and have it calculate the total time from that (1.4 hours)?

If that's possible, will it autofill the OUT from the last IN for the aircraft I've selected? For owner/pilots, that's ideal.

If all of that is possible, how do I create a "currency report" that will tell me when my next oil change is due (by Hobbs time) and give me a reminder 3 or 4 flight hours in advance?

If none of this is possible, why not? If it is, why can't I find it in the help?

Hi Craig,

We will add this as a suggestion for the next version. We don't tie times to hobbs, tach, etc. as they all differ in requirements, accuracy, and methods of logging flight time. Military log flight time from wheels up to wheels down, not 'engine running time' such as Hobbs time, and my corporate/airlines log their time similarly. Therefore, in the goal of Logbook Pro, it was not to tie the software to a particular rule, regulation, or aircraft/usage. We intended to leave it up to the pilot to determine the amount of time to log, then enter that value for Logbook Pro to use.

AS for oil changes and other maintenance items, we are looking at adding this with version 2 as well as the potential hobbs/tach and other time input methods.

Thank you for your comments as they promote new features in upcoming versions.

I didn't realize that the vast majority of your customers were military. I figured they were probably private pilots and maybe some instructors. I can see why you would do it the way you did, then.

While I understand the design goal of not tying it to one particular rule or mode of use, it seems you've done exactly that here. If you don't use your watch to make your log entries, then your particular mode of use isn't supported.

Thanks for considering this for a future version. I'll have to either write my own or keep looking.


The majority is not military or any group for that matter. Logbook Pro is actually more catered to the general aviation/hobbs user in that from Hobbs you get a hours.tenths value, therefore it's a direct fit to Logbook Pro's design. OUT/IN (or gate to gate / block times) and Takeoff/Landing times are not required entries, simply the Date, Type, Ident, Route, and Duration. Duration is directly derived from your hobbs reading.

I'm not sure I understand the problem. In your example, you simply enter your hobbs delta of 1.4 in the Duration column and other time columns, as required.

The 'problem' such as it is -- it's not that big of a deal -- is that it would be nice to simply enter the hobbs end time of each flight in a particular airplane. Start time would default to the previous hobbs end time. The program would compute the difference.

Once you're entering hobbs times for an airplane it becomes trivial to add features like 'warn me when the hobbs time approaches x + 500' where x is the last time I performed a recurring AD that needs to be checked every 500 hours. You could also use it for oil changes, 100-hour inspections, etc.

I agree I can just enter the duration of the flight. But when I fly I don't write down the hours and tenths. I write down the ending hobbs time. I put this in an unused column of my logbook and calculate the duration of the flight when I make the log entry. It's no big deal, but if I switch to your program I have to write down hobbs out/in or takeoff/landing times instead of just the final hobbs number.

Having the hobbs time in my log makes it easy to know when service is due by comparing to the aircraft logs.

Hi Neal,

I am evaluting LB pro and am so far impressed. I currently keep my log in an access database and am an owner-operator. I expect that Craig is as well. For those of us who usually fly one plane, our own, the easiest and best way to track time is via the hobbs meter. (Granted there are some issues, on my C340, it logs wheels up time only so my database includes a taxi time field which when totaled with hobbs gives block time). By making the last hobbs end time, the default start hobbs time for the next flight, you select the date only once per entry, it is not necessary to enter a take off time and date, landingtime and date for each entry. As for the difference in hobbs meters, a simple "Ground Run/taxi time" fieldtakes care of the difference between an oil pressure/master switchhobbs meter and a WOW(weight on wheels) meter.

One other comment, and this is most likely user error on my part. I was able to enter a flight date that was different from the "in/out" dates????

Backon the owner operator topic, I also agree that somemaintenace tracking would benice. Of course this may not have enough appealfor an ROI.... It would be nice to be able toenter an Annual, ELT battery, IFR Cert/Transponder check, 100 hour, oil change etc etc. and have the software alert you that these items need to be handled. The issue for an owner operator is that our logs and the A/C logs aretightly coupled and just these features would be very valuable. It is about the same as a medical for the pilot only tracking it by N# foreach airplane, the main difference being some items are date related and some are time related.

I hope this makes sense, I love what I see so far in the software.

Best Regards