Primarily for general aviation discussion, but other aviation topics are also welcome.
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By T67M
#1695033
defcribed wrote:
JAFO wrote:How do you log decimal and round to the nearest 5 minutes?


As an example, you're brakes off at 09:59 and brakes on at 11:28.

Round 09:59 to 10:00.
Round 11:28 to 11:30.
10:00 to 11:30 is logged as 1.5.


A counter example:
Blocks times of 10:47 to 11:13 (=26 minutes, or 0.4)
Rounding to five minutes gives 10:45 to 11:15.
Convert to decimals "10.7" to "11.3" = 0.6, or 35 minutes.

By effectively rounding the numbers twice, any errors are magnified.
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By defcribed
#1695041
T67M wrote:
defcribed wrote:
JAFO wrote:How do you log decimal and round to the nearest 5 minutes?


As an example, you're brakes off at 09:59 and brakes on at 11:28.

Round 09:59 to 10:00.
Round 11:28 to 11:30.
10:00 to 11:30 is logged as 1.5.


A counter example:
Blocks times of 10:47 to 11:13 (=26 minutes, or 0.4)
Rounding to five minutes gives 10:45 to 11:15.
Convert to decimals "10.7" to "11.3" = 0.6, or 35 minutes.

By effectively rounding the numbers twice, any errors are magnified.


I only convert the final flight time to decimal, not the start and finish times. So in your example I would round to 1045 and 1115 as you do (and enter those times in my logbook) and then that 30 minutes = 0.5.

Also, if I happen to round up on the start time (thus excluding a minute or two) then I tend to round up on the finish time (if required) so as not to potentially chop a whole five minutes off. Same applies the other way around. As often as not though, at any given brakes on or brakes off the minute hand on my watch is close enough to something ending with a 5 or 0 that it really doesn't matter.

The only way to be truly accurate is record it to the nearest minute and not use decimals. I rather wish I had done that from the very beginning.
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By QSD
#1695096
.....The only way to be truly accurate is record it to the nearest minute and not use decimals. I rather wish I had done that from the very beginning.


But if you did this, you would probably introduce more errors in the adding up process, assuming you are still using pen and paper.

Every time I do a CCC for a test ready student I have to go through their logbooks and correct any errors. Those students using decimals as you describe (ie rounding block times to the nearest 5 minutes and then expressing the total time as a decimal) seem to make the fewest errors. Those students who are adding up hours and minutes rarely get their page totals correct and can sometimes be a long way out.
By Lefty
#1695163
For the first 20 years of flying I used hours : minutes. It was simply what we all did. My early log books are full of tipex and (less pretty) corrections, as we all made loads of mistakes in our adding up.

Then I discovered that I could use decimal hours - and suddenly no (or very few) mistakes.

Until recently, my aircraft log books were still in Hrs:mins, and like my own logbooks - had lots of errors and corrections. I’ve now switched to decimal and all is great.
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By derekf
#1695184
I've used decimal since I started (possibly from my first instructor) - quite surprised to find people did it other ways a year or so ago.
Debated switching, but to be honest suspect it's just a simple and less likely to confuse if I stick to decimals (based on 6 mins not 5 mins). My logbook.aero does the same so helps me check my rounding is correct :) and we use decimals in aircraft logbook as well...
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By defcribed
#1695324
derekf wrote:I've used decimal since I started (possibly from my first instructor) - quite surprised to find people did it other ways a year or so ago.
Debated switching, but to be honest suspect it's just a simple and less likely to confuse if I stick to decimals (based on 6 mins not 5 mins). My logbook.aero does the same so helps me check my rounding is correct :) and we use decimals in aircraft logbook as well...


Do you write actual brakes off/on times in your logbook or round them to the closest six minutes?
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By davelee212
#1695331
I've always logged in hours and minutes, perhaps my first flight instructor did it that way (I can't remember) or maybe it just made sense to me at the time. I don't tend to have any difficulty adding it up. I tend to stick it all in a spreadsheet as well so any mistakes are easily spotted when I add things up at the end of a page.

Dave
By riverrock
#1695345
HH:Mi for me - and logbook.aero keeps my terrible arithmetic correct. Both Share-o-planes are also logged in HH:Mi , as are all those who I've seen at my club. Everything rounded to 5 minutes, and we always log 5 minutes taxi time (for personal logbook and for paying).
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By derekf
#1695373
defcribed wrote:
derekf wrote:I've used decimal since I started (possibly from my first instructor) - quite surprised to find people did it other ways a year or so ago.
Debated switching, but to be honest suspect it's just a simple and less likely to confuse if I stick to decimals (based on 6 mins not 5 mins). My logbook.aero does the same so helps me check my rounding is correct :) and we use decimals in aircraft logbook as well...


Do you write actual brakes off/on times in your logbook or round them to the closest six minutes?


Closest 6 mins and record decimal only
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By Dave W
#1695392
I do find interesting the discussion of why and how people use different (allowable) techniques for logging time.

But the thread discussion has diverged some way from what I took from the OP, which I found rather depressing as it would appear that the CAA reviewer found it acceptable to bounce the application at first sight without the simple sanity check of looking at even one line of the logbook to line up clock times with elapsed time to see how the applicant had logged the training.

Instead, the assumption seems to have been that of course the applicant and training organisation were wrong/trying it on, rather than initially taking the applicant's side and assuming that it was correct so then checking why it apparently wasn't - rather than the other way around. If they had, it would seem that the actual times could have been determined from available paperwork rather than causing the time, angst and further expense to the applicant that did result. And let's not forget the applicant will have paid a fair wedge anyway to get the apparently cursory examination that they did.

If that sounds jaded, then it is: Since I have recently experienced exactly that attitude with a friend's applications (yes, more than one) where the worst possible interpretation by the CAA reviewer has been taken each time - regardless of tests passed or competences previously demonstrated - with the upshot that he is facing a likely >£1,200 additional cost for no practical or safety reason.

I can't say I've been that impressed with one of his (several) training providers either, who effectively left it to him to fill out complex application forms with limited to no guidance and in fact erroneous records signed off which twice needed to be corrected. Which was done with poor grace despite being (a) Their error, and (b) uncorrected would have definitely led to a CAA bounce in itself.

Those are situations that I have direct knowledge of. Yet these stories are not uncommon on here either.

My conclusion is that there is something apparently awry in the training and approvals process in too many cases in the UK at the moment.

Thankfully there are knowledgeable, positive, generous and helpful people who give freely of their time to help put things right. Pleasingly, many of them post on here.

And no, I don't intend to provide further details here on the above just yet as the situation is rightly under review for appeal.
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By flybymike
#1695409
But the thread discussion has diverged some way from what I took from the OP, which I found rather depressing as it would appear that the CAA reviewer found it acceptable to bounce the application at first sight without the simple sanity check of looking at even one line of the logbook to line up clock times with elapsed time to see how the applicant had logged the training.

Instead, the assumption seems to have been that of course the applicant and training organisation were wrong/trying it on, rather than initially taking the applicant's side and assuming that it was correct so then checking why it apparently wasn't - rather than the other way around. If they had, it would seem that the actual times could have been determined from available paperwork rather than causing the time, angst and further expense to the applicant that did result. And let's not forget the applicant will have paid a fair wedge anyway to get the apparently cursory examination that they did.

If that sounds jaded, then it is: Since I have recently experienced exactly that attitude with a friend's applications (yes, more than one) where the worst possible interpretation by the CAA reviewer has been taken each time - regardless of tests passed or competences previously demonstrated - with the upshot that he is facing a likely >£1,200 additional cost for no practical or safety reason.

A refreshingly cynical view of the CAA; truly worthy of a post by Cockney Steve. :wink:
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By skydriller
#1695415
flybymike wrote:A refreshingly cynical view of the CAA; truly worthy of a post by Cockney Steve. :wink:


But is it generally true or an isolated case?

Regards, SD..