Definition of "DAY" in the AUS CAR/CAO?

[Avturbound]

Hi guy's

For those that are up to speed with their Airlaw knowledge I am wondering if anyone knows where it gives the definition of a day whether it be in the CAR's or CAO's?

Much appreciated. :ok:

[ControlLock]

Try the AIP GEN 2.2 Definitions section or equivalent Jepp document.

[5-in-50]

Other more knowledgeable peeps might add to this, but I have a feeling that in typical fashion, The regulator's definition could be found by understanding what day 'is not', rather than what it is.

Look for 'civil twilight', 'end of daylight' etc. Day is the the time that is not encapsulated by the definition of 'night'. hah!

[Avturbound]

Hey mate,

I understand what you mean however going of the definition of civil twilight/daylight will not help in relation to finding the definition of a day.

To put it in different terms for instance the flight and duty times for a pilot they use the word day quite a bit. so where does it give the definition of a day. is it 24hrs 12am-12am ? etc

[Woodwork]

It's actually more complex than you'd think. Normally the font of all wisdom on legal definitions is the wonderfully-titled Acts Interpretation Act (1901), but it offers no guidance beyond the date and time, for the application of law, shall be the date and time in local time at whatever part of the Commonwealth you happen to be in.

There's a lot of common law about 'days', which mostly suggests for the purposes you're asking that it's considered to be a 24-hour period commencing at midnight in local time.

(There's also a wonderful nugget in the AIA(1901) about things being due on a weekend or holiday are legally considered due on the 'next day that is not a Saturday, Sunday, or holiday', which might help in an argument with CASA about renewal dates one day.)

[Creampuff]

Schedule 1 of the National Measurement Regulations 1999 defines these time intervals:

‘day’ means 86,400 seconds

‘hour’ means 3,600 seconds

‘minute’ means 60 seconds

‘second’ means the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the 2 hyperfine levels of the ground state of the caesium 133 atom.

AIP appears to define only the meteorological phenomenon of ‘day’, not the time interval.

[MakeItHappenCaptain]

Ever seen those beginning and end of daylight graphs in the AIP's (or Jepps)?

AIP GEN 2.7
1. DAYLIGHT AND DARKNESS GRAPHS
1.1 “Night” is that period between the end of evening civil twilight and the beginning of morning civil twilight. For all intents and purposes, first light should be construed as the beginning of civil twilight, and last light as the end of civil twilight. The terms “sunrise” and “sunset” have no relevance when calculating daylight operating times for the VFR pilot.:hmm:

[601]

definition of a day

I have heard of someone in Canberra who can come up with a definition for you:rolleyes:

[Creampuff]

Ever seen those beginning and end of daylight graphs in the AIP's (or Jepps)?So, how do those graphs help here:A pilot shall not fly and an operator shall not roster him or her to fly in excess of 30 hours in 7 consecutive days.

[Oktas8]

Avturbound, have you considered providing some context for your question? E.g. I did thirty hours flying since last Wednesday, 9pm. Can I go flying again tonight at 9:30pm?

Might stimulate a bit more educated discussion. Or gossip anyway, which is almost as fun...

[MakeItHappenCaptain]

Creampuff,
They don't, but if someone is having trouble applying the most basic of flight and duty times, maybe this industry isn't for them?
How does the SI definition help?

Avturbound,
Treat a "day" as a period of duty and the preceeding rest period. If you're trying to twist it any further, then it would seem as if you were trying to bust a rule.:=

[Creampuff]

How does the SI definition help?Errrmmmm, perhaps it helps because it’s the answer to the OP’s question. It is authoritative definition of what ‘day’ means when that word is used to mean a time interval.

[Harry Cooper]

Try looking in your relevant CAO 48 flight and duty schedule or exemption, in the definitions. Will most likely be midnight to midnight.

[Creampuff]

I have.

And it's not.

[AerocatS2A]

Errrmmmm, perhaps it helps because it’s the answer to the OP’s question. It is authoritative definition of what ‘day’ means when that word is used to mean a time interval.

Yeah but it doesn't define when it starts and stops, which is probably what the OP really wants to know. (I'd work on midnight to midnight, but it's always nice to find that sort of thing in writing, particularly if your company is trying to screw you over.)

[Creampuff]

So how does midnight-to-midnight help the OP, here for example:A pilot shall not fly and an operator shall not roster him or her to fly in excess of 30 hours in 7 consecutive days.The SI definition works perfectly and precisely in that context. Every second of every day, 7 consecutive days elapse and a brand new period of 7 consecutive days starts. :ok:

[MakeItHappenCaptain]

Yeah, your definition could be construed that way.
Rules don't say what definition you have to use, though, therefore it could be taken that they don't say you can't use another definition, ie. From start of rest period to end of duty period being classed in its entirity as one day.

Hypothetically,
Day 1 (after a sufficient rest period) starts 6am
Day 2 started rest period before 10pm
Day 3 off
Day 4 started duty at 6:01am thus covering the two consecutive 10pm to 6am periods
Day 5 normal
Day 6 normal
Day 7 started at 5pm finished at 11pm

(So in this case the "7 days" being 7 days and 11 hrs...)

This would actually be a safest case scenario by Creampuff's suggested definition.

How would you present a set of times that breaches your angle?
(Not being smart, just the brain's going fuzzy after not enough sleep.):}

[Creampuff]

Let’s make it as simple as possible and assume that this rule is the only one about flight and duty times: “A pilot shall not fly and an operator shall not roster him or her to fly in excess of 30 hours in 7 consecutive days.”

Ms Bloggs is rostered to fly (all times local):

2200 March 1 to 0800 March 2

2200 March 3 to 0800 March 4

2200 March 5 to 0800 March 6

May Ms Bloggs be rostered to fly at all on 7 March?

I would have thought she may be rostered to fly from 2200 on 7 March, because 2200 on 7 March is the start of the 8th consecutive ‘SI day’ since 2200 on March 1.

However, if a ‘day’ means ‘midnight to midnight’, she can’t be rostered at all on 7 March, because all of March 7 is part of the 7 consecutive ‘days’ that started on March 1.

[Harry Cooper]

Creampuff, I just looked in my company docs and as part of the part viii exemption it clearly defines a day to mean from midnight local to midnight local.

A problem we have commonly is that when rostered for a Night shift from 6pm to 6am the following morning, it is technically 1 shift but 2 days so if you call in sick for that shift you lose 2 days of sick leave.

[MakeItHappenCaptain]

thought she may be rostered to fly from 2200 on 7th March

Sorry to harp on, Creampuff, but your example is no in both cases purely by either interpretation of seven days. (Neglecting rosters in excess of eight hrs, multiple rosters in excess of eight hours and no consecutive days off).

By midnight to midnight definition, yes, you would breach if you started on the 7th.
By SI definition, 10pm on 7th is only the start of the sixth day. You still breach.

Bear with me.

1st 10pm to 2nd 9:59pm. 24hrs total (1 day)
2nd 10pm to 3rd 9:59pm. 48hrs total (2 days)
3rd 10pm to 4th 9:59pm. 72hrs total (3 days)
4th 10pm to 5th 9:59pm. 96hrs total (4 days)
5th 10pm to 6th 9:59pm. 120hrs total (5 days)
6th 10pm to 7th 9:59pm. 144hrs total (6 days)
7th 10pm up until 9:59pm in the 8th is still within 7 days. Bust.

I can't come up with any scenario where the SI definition is more limiting than the midnight one.

Anyone?:confused:

[Creampuff]

Whoops – you are correct. I made a mistake.

2200 on 1 March to 2200 on 8 March is 7 SI days.

I will try to come up with a scenario in which it makes a difference.

[Creampuff]

Let’s see if I can get it right, this time:

Ms Bloggs is rostered to fly (all times local):

2200 March 1 to 0530 March 2

2200 March 3 to 0530 March 4

2200 March 5 to 0530 March 6

2200 March 6 to 0530 March 7

(So, if I’ve worked the maths correctly, that adds up to 30 hours of rostered time so far.)

May Ms Bloggs be rostered to fly at any time on 8 March?

I would have thought that under the ‘midnight-to-midnight’ day measurement, the answer is ‘yes’ because 8 March is day 8.

However, under the ‘SI day’ measurement, the answer is ‘not until 2200’, because day 7 does not finish until 2200 on 8 March. :confused:

[Woodwork]

I guess my previous response was a bit too muted to be noticed, or maybe the phrase "common law" was misconstrued, but case history / common law in Australia defines a day as a 24-hour period commencing at midnight in local time.

This is the legal standard to which you, or any employer, will be held if presenting a case/prosecution/defence before any court or tribunal in Australia.

If the rules or regs mean a 24-hour period, then that's what they say - they do in the drug & alcohol portions, for example.

[Creampuff]

I would have thought that legislation like the National Measurements Act and regulations under it can oust the common law, but in any event, what is the effect of the common law definition of ‘day’ in scenario above?

May Ms Bloggs be rostered to fly on 8 March before 2200 hours?

The only rule we’re applying is:A pilot shall not fly and an operator shall not roster him or her to fly in excess of 30 hours in 7 consecutive days.

[Oktas8]

I'll bite this hook...

I would say yes she can fly at any time on the 8th, but for no more than 2 hours. Otherwise she will do more than 30 hours since the beginning of the 2nd.

My reasoning is this: as she is not obliged to maintain a logbook with specific times of departure and arrival, she cannot be obliged to maintain a flight time limitation to a rolling 'SI day'. Only dates are recordable, so only dates (midnight to midnight) are enforceable.

Yes, block times are recorded elsewhere, but nowhere that Mrs Bloggs is required to have access to before deciding whether to accept another flight.

[Capt Fathom]

Creamie.

I guess you are ignoring the 2 local nights in 7 for this argument!

[Creampuff]

Yes, CF, because the answer to the OP’s question would benefit from application of Ockham’s/Occam’s Razor. The assumption is that one rule, and one rule alone, applies.

O8: Setting aside the fact that the rule says nothing about ‘logged’ hours or dates, the rule applies to operators as well as pilots. The operator is prohibited from rostering Ms Bloggs to fly [note: not ‘log’] in excess of 30 hours in 7 consecutive days.

Let’s align ‘midnight-to-midnight days’ with ‘SI days’, by moving Ms Blogg’s roster forward 2 hours, to see what happens.

Ms Bloggs is rostered to fly:

0001 March 2 to 0730 March 2

0001 March 4 to 0730 March 4

0001 March 6 to 0730 March 6

0001 March 7 to 0730 March 7

Ms Bloggs has been rostered to fly 30 hours in 6 ‘midnight-to-midnight days’, which happens to coincide with 30 hours in 6 ‘SI Days’.

Whichever way you measure it, it seems to me that the effect of the rule is that Ms Bloggs must not be rostered to fly again until 0001 on March 9. That’s 30 hours and 30 minutes after Ms Bloggs finished the roster at 0730 on March 7.

Now subtract 2 hours (or any period ranging from 2 minutes to 23 hours and 59 minutes) from all the times in the roster. It would be a really weird outcome if merely moving that roster backwards (or forwards) resulted in the mandatory no-roster/no-fly period being any different from the one that applies if the roster starts at 0001 hours.

The really weird outcome is avoided if 'SI days' are used for the calculation.

Key point: we’re only assuming one rule applies here.

[Oktas8]

Good points CP.

However, I think it is unconscionable to place a restriction on a pilot when that pilot has no reasonable way of knowing whether the restriction applies. Let me explain.

I realise that your excellent example is only for the 7 day rule. Got it. For the purposes of this paragraph however, imagine that the only rule is the 900hr / 365 day rule. Imagine we've expanded your hypothetical roster so it goes to 900 hrs in exactly 365 days. How would Ms Bloggs know what time of day she did that flight 366 days ago, so she knows when she can start flying again? Ms Bloggs can't consult the operator's records - he was working her too hard, so she quit, and now she is onto her second employer, and the first bloke won't even speak to her let alone let her examine his flight records. And Ms Bloggs can't possibly remember times of day or when rest periods started & stopped. So she's stuck with the only records that CASA require her to have and to use, which is her logbook. All she can do is use logbook dates to determine when she can fly again.

Note in this case, "logged" hours are the only ones available, even though you've rightly pointed out that the CAO doesn't mention that word. Similarly, her current operator can't help, as his records only go back three months to when employment began. Despite his legal responsibility to roster Ms Bloggs correctly, he is just as dependent on her logbook as she is.

The adjusting the times to seemingly get a free day, as you've done to provide an example, is not so weird. In the first case, I think there is no day off owing. In the second case (roster moved back 2hours 1minute) there is a day off owing according to my reasoning. However, you've gotten a day off on the 1st of the month in the second example. So in the long term it averages out exactly the same.

That's why I suggest using dates in the logbook to satisfy the FTL. However, I could be wrong - all the above is just my highly non-lawyer-like reasoning, I admit.

Good discussion.
O8

[Woodwork]

Let’s see if I can get it right, this time:

Ms Bloggs is rostered to fly (all times local):

2200 March 1 to 0530 March 2

2200 March 3 to 0530 March 4

2200 March 5 to 0530 March 6

2200 March 6 to 0530 March 7

(So, if I’ve worked the maths correctly, that adds up to 30 hours of rostered time so far.)

May Ms Bloggs be rostered to fly at any time on 8 March?

I would have thought that under the ‘midnight-to-midnight’ day measurement, the answer is ‘yes’ because 8 March is day 8.

However, under the ‘SI day’ measurement, the answer is ‘not until 2200’, because day 7 does not finish until 2200 on 8 March.

In this scenario, using the 0000-2400 definition, Ms Bloggs has flown for 7 consecutive days for exactly 30 hours. On March 8, we can lop 2.0 hours off from March 1, but we still have the 5.5 accrued between 0000-0530 on March 2. That limits us to 2.0 hours only on the 8th - which would not preclude an 082200-090530 segment being flown that night. Ms Bloggs could also, subject to appropriate rest of course, fly a shorter 2.0 segment any time on the 8th.

Using the SI "preceding 24 hour" rule, we get a more restrictive result - no flying at all on the 8th and not prior to 0530 on the 9th.

Edit: Amplifying on the above, the reason I say no flying at all on the 8th is because the rule says "roster" for flying, that is, the second Ms Bloggs walks onto the flight deck she's been ROSTERED for a 7.5 hour segment, regardless of the fact that most of those hours will be acquitted later.

If you want to be less hung up on the word "rostered", then the SI definition allows Ms Bloggs to commence duty at 2200 on the 8th, since each minute after 082200 we can dismiss the equivalent minute after 012200. This interpretation equals the flying we'd be allowed to do in the 0000-2400 definition.

[Creampuff]

That’s my reasoning, too, WW.

O8: The meaning of the word doesn’t change depending on whether it has ‘365’ instead of ‘7’ in front of it. However, I reckon ‘SI day’ v ‘midnight-to-midnight day’ doesn’t make a schmick of practical difference in the 365 case.

When you wake up on the morning of midnight-to-midnight day 365, no one’s going to have a clue whether the hours you logged on midnight-to-midnight day 1 were for a flight that started before midnight. If all those hours add up to 899.9, good luck to you: it’s a problem I’d like to have!

[LeadSled]

Aaaarhhhhh!!
For the good old pommy regulations (don't really know if they have filtered into EASA's new flight time rules), but, for the pommy exams of yore, a day could be:
A) Mean Sidereal Day or:
B) Calendar day, (always GMT, this was before UTC) and
"the rules" made clear which day was "a day".
and daylight and darkness were were precisely defined.
On a day to day basis, we seemed to manage OK in picking the right definition of day for the day --- so to speak.

Tootle pip!!

[gaunty]

Creampuff mon vieux.

In the context of Flight and Duty times might the operative word be "local"?

There are now some very well respected and accepted FRMS programmes that account for the rotation of the earth in its orbit around the sun in the application and effects of circadian thingummy rest periods and duty times

We go too fast nowadays for the old rules to have any relevancy. :cool:

[Oktas8]

no one’s going to have a clue whether the hours you logged on midnight-to-midnight day 1 were for a flight that started before midnight

Exactly my point. So are you going to use midnight-to-midnight for all FTLs, or SI for limitations over a shorter time period and calendar day for longer time periods? In the long run it makes no difference to hours flown, so I use the principle of consistency.

For the hapless Ms Bloggs on her overnight shifts, I recommend recording flight dates in UTC. Perfectly legal and gets around the problem of taking off on day 1 and landing on day 2. KIS.

[Mainframe]

CAO 48, Industry Exemptions, Flight Crew Flight and Duty Limits

2. Definitions

2.2 Day: A day is the period between local midnight and the subsequent local midnight.

[gaunty]

Mainy old chap. G'day.

Quite so. :ok: however in times modern perhaps that "local" time should be further defined as "home base".

[Creampuff]

A definition in an exemption does not make it so for the regulations.

However, it does show why the discussion is academic in the context of the CAO 48 series: no one's actually obliged to comply with them, irrespective of what they mean. (Another regulatory dog's breakfast).