rounding block time

[Cirrostratuss]

Could someone point me in the right direction? Looking for a reference in the JAR's that says we can round the block times to the nearest 5 minutes.

Thanks!!

[S-Works]

I have always rounded block time using standard 'Swedish' rounding. Otherwise it is a monumental pain in the bum to add up. Over time it naturally evens itself out. No different from using decimals.

[Genghis the Engineer]

I'm not sure I've ever seen anything in any civil regulations - it's just custom and practice really.

You'll certainly never be criticised for doing it, except possibly if learning to glide where 1-2 minute flights aren't all that unusual.

G

[wsmempson]

I've never heard it called "Swedish Rounding" - it sounds very interesting...!;) Is that like a "spanish practice" or a "French letter"?

I think we're on the same page here; if the flight time comes out as 1hr 12minutes, it goes in the log as 1hr 10minutes. If it comes out as 1hr 13minutes, it goes in the book as 1hr 15minutes.

If you're working in decimal, I can't help!

[S-Works]

It is actually a currency term, but the principal is the same and as you describe!

[Cirrostratuss]

Yeah, I've been rounding since I started using minutes rather than decimals (years ago). But I remember vaguely reading about it before adopting the practice. I thought I read it from the JAR's but maybe I'm just mistaken.

Thanks for the feedback, appreciate opinions and an official reference If anyone comes up with one.

[tmmorris]

I record flight times to the nearest minute but then round them to decimals (6 minute chunks, not that hard to do) for the hours columns. That way if the CAA wanted to go through it and work out the actual precise hours they would be welcome, but otherwise if they are prepared to trust my rounding it makes the maths easier.

Confusing sometimes as I record exact minutes in UTC but our club likes times on the tech log rounded to 5 minute chunks in Local. Sometimes I get that one wrong...

Tim

[S-Works]

Blimey! talk about making life difficult!!! To the nearest minute! My watch is not that accurate nor my eyesight!

It should be born in mind that we are allowed to add 5 minutes either side as an arbitrary figure for Taxi time. Recording to the minute is a little excessive in context!!

I keep my aircraft logbooks in decimals but as I measure my day in hours and minutes I keep my personal logbook the same.

[jezbowman]

It should be born in mind that we are allowed to add 5 minutes either side as an arbitrary figure for Taxi time.

Is that an official thing then? If so, where is it quoted from?

I've recently joined a (very newly formed) group based around a DR1050 and they are using brakes off to brakes on to accumulate engine, airframe and maintainance totals. A couple of people I've spoken to (including one who operates a public catagory C of A machine) tells me that you normally count these totals in airbourne time, not brakes-on brakes-off time.

[worrab]

Saw a recommendation somewhere that groups/hire craft would do well to use airborne times since it would avoid the temptation for members to omit run-up checks and taxi at a gazillion miles per hour.

[tmmorris]

What's the problem?

Glance at your watch on brakes off, takeoff, touchdown, brakes on and note them on the PLOG. What's difficult about that? And if your watch isn't accurate to within a minute, get a new one. Seriously.

How accurate do you make your position reports/estimates? If you cross the FIR boundary, do you tell London Info that you estimate the FIR boundary at around 10 o'clock? Crossing controlled airspace, do you call them and ask for zone transit, estimating zone boundary at around 20 past? No, I didn't think so.

Maybe I'm anally retentive, but I do expect to be able to record times to within a minute, and calculate ETAs to within a couple either way.

Tim

[S-Works]

Tim. not saying that it can't be done, just asking the point of making life difficult for yourself when you add up your logbook!!!

Recording time in your logbook has booger all to do with a position report!!

But then I guess for me every minute does not need to count so I take a more philosophical approach!

[Rod1]

So you want me to look at my watch as I leave the ground and as I touch down? You are having a laugh! I use the same system as Bose and knock 10 min off for taxi. My GPS measures takeoff to landing (>40kn <40kn), and the two normally agree to within 1 or 2 min.

Rod1

[Agaricus bisporus]

What has take off and touchdown got to do with it? (UK CAA) It really is a pity people don't bother to read the regs as this is so clearly laid down...
Flight time in the logbook is brakes off with the intention of getting airborne to when the a/c next comes to a rest - that's it. ie brakes on to off. What is hard to undestand about that? This has nothing to do with the Hobbs or airborne (power on) hours that go in the tech records.

Nothing says flight time has to be recorded to the nearest any kind of unit either. Why can't people read the regulations????

Traditionally hours have been recorded to the nearest five minutes, tho you might sensibly prefer to round to the nearest six minutes - unless you want to make work for yourself - what's the differnece between rounding to 5 or 6? None! Just a dam sight easier with a calculator if the hour is 10/10ths as opposed to 12/12ths. Pretty obvious really.

Military time is traditionally recorded as airborne time only; the CAA is perfectly happy for this time to be adjusted by a notional amount to take account of for taxi time as accepted in CAA regs. All my mil time was augmented by 15 mins per hour - 10 mins taxi out and 5 mins taxi in. Perfectly reasonable, honest and practical. At some very slow airfields it might be appropriate to increase this - Cranfield for instance.

Apply "reasonable, honest and practical" to your times and you won't be adrift in either your logbook or your general conduct in the air. Don't be unreasonable (ie greedy) and it won't be a problem.

Easy!


How is this even a problem?

[Agaricus bisporus]

Heavens above! What next?

What is the definition of "flight time"

If you don't know then look it up!

I'll give you a clue - something to do with "Brakes off with the intention of taking off" Which would include taxi out, mag checks, fail mag checks, taxi back and park. (after all, you've exercised all the Captaincy required during that time? to "Brakes on at the completion of the flight"

In other words brakes on to off.


Nothing says what units it is recorded in either. What is the difference between time recorded to the nearest 5 or 6 minures or even the nearest 3 seconds?

Nothing!

- as long as there are enough flights for the numbers to average out, which even over the period of a first solo they would, let alone a PPL, let alone even a CPL

Logbook time is brakes on - off outside the clubhouse, or on/off stand when you're in a 737. No difference.

[tmmorris]

Yes, Rod1, I do, and so did my instructors and examiner for my PPL. Maybe they were responsible for the anality.

All you do is glance at your watch (or the clock which by law you carry in the aircraft) as you rotate, make a mental note, then write it down when you have a second. I always say it out loud which has the benefit that if I have a passenger I can ask him/her if I forget...

1...2...3... Ts & Ps in the green... airspeed active... 55 knots: rotate ... airborne time 35... FERAF check... 'G-ABCD airborne, to approach'...

Easy to fit in, as far as I can see, unless you are in a jet fighter. On touchdown I note the time as I roll off the runway onto the taxiway.

Incidentally as I think has been mentioned the interest in takeoff/touchdown times is that the tech log requires these for calculating maintenance. Plus knowing the takeoff time enables you to work out your ETA for the first waypoint, unless you have the luxury of climbing into the overhead to set course.

Tim

[Gertrude the Wombat]

So you want me to look at my watch as I leave the ground and as I touch down?
The one time I failed to record any time at all I just phoned ATC and asked them for my take off and landing times.

[S-Works]

Bloody hell! What an argument over nothing.

Everyone should do as they see fit within the regs. Personally I just do my logbook from the GPS most of the time and only log the airborne time. At work they very kindly send me a print out every month that I transpose to my log book.

Chill people.

[tmmorris]

Sorry, didn't mean to come over as tetchy. Just a bit bemused as I thought everyone did it the same way I was taught. Oh well!

Tim

[pmh1234]

We log flight time. I usually forget to note it so I note the time when in flight from the GTX330 capable of showing the flight time. If landing without proper notes I log the flight time from the transponder. Logging Flight time gives less hours on the aircraft. For my personal log book I add app 10 min in total - some for the takeoff and some for the landing to make it fit with 6 min increments.
All renting on our aircraft is paid on tach time only.

[ExSp33db1rd]

Swedish Rounding

In NZ all coins below 10c were declared illegal about 2 years ago.

It was widely feared that removing the small denomination coins would cause massive inflation, so Swedish Rounding was suggested - what have the Swedes got to do with it ?

In my book, everything up to and including 5c goes down - i.e. in my favour, and anything 6c or above goes up to the retailers favour.

Some retailers agree, others don't, so if an item is priced at 5c and I am charged 10c I then produce my Credit Card ( or my cheque book) that calculates to the nearest cent on my bank statment, and I can write a cheque if I have to, or indulge in Internet Banking to settle at the end of the month. Drives 'em mad, but they have a choice !

The Americans still manage with 1 cent coins, so why NZ had to go for this system beats me. Many US retailers have a saucer on the counter with 1 cent coins in it, and a note - If you need a cent take one, if you have a cent left over, leave one' - works well, 'cos one is always one coin short, and it saves changing a $100.oo bill !

Flying hours ? Chock to chock - keeps the maintenance bills down, to.
My Hobbs ticks over in decimals. Before that I had a calculator that adds up hours and minutes. ( didn't worry about the seconds )

[tmmorris]

Most scientific calculators can add degrees, minutes and seconds, so you can use that to add hours, minutes & seconds. (E.g. all the Casio range, as far as I know.)

NALOPKT...

Tim