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Author Topic: C-check scheduling  (Read 6362 times)

Offline Kazari

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C-check scheduling
« on: July 14, 2009, 10:29:03 PM »
(I apologize if this has been covered -- I DID search. I even remember reading about it.)

I would like the ability to schedule C-Checks ahead of time so I can "spread the love." I know I can do this manually, but if I could do it on a schedule, it would make cash-flow much more predictable.

I saw that something SIMILAR to this was proposed, but I wanted to be very clear.

I propose that http://www.airwaysim.com/game/Aircraft/Maint/xxx/ OR http://www.airwaysim.com/game/Aircraft/My/?sort=Reg&view=tech&sort2=up&page=1 (or both) have a field or link added that says "Schedule C-Check" so that we can set the date of the next check.

BD

  • Former member
Re: C-check scheduling
« Reply #1 on: September 18, 2013, 01:40:20 PM »
Just had the same conclusion. 

With a large number of aircraft, this becomes untenable to manage, as one by one it requires near full time attention to the game to try to spread them out.  Thus one is subject to the randomness of how the c-checks cluster, which can play havoc with your cash flow.

Definitely could use the ability to schedule these ahead of the default time limit they come to the airline with to give them proper spacing.


Offline LemonButt

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Re: C-check scheduling
« Reply #2 on: September 18, 2013, 07:01:59 PM »
If you take a step back, you will realize how ridiculous this is.

Instead of paying for C-checks when they are due, you want to pay for them before they need to be paid for, which actually hurts your cash flow at the macro level because you're paying for unnecessary maintenance.

Statistically, the frequency of C-checks is a Poisson distribution and subject to the central limit theorem.  Which basically means that those "clusters" of C-checks will start to converge on the theoretical mean.  Or in less technical terms, the more aircraft you add to your fleet the less variation you will experience in weekly cash flow due to C-checks.

So as it stands today, the problem is only a problem if you have a small fleet, and if you have a small fleet you should be able to use the existing features to "space out" your C-checks, which is still a losing proposition because you're giving up free cash flow today to pay for unnecessary maintenance versus using future cash flow to pay for required maintenance.  If you add in the time-value of money, it becomes even more of a no-brainer.  If you're really worried about these short term fluctuations, the solution is to always have $1 million in cash on hand and treat that as your $0 level so there is always a reserve for C-check expenses.

IRL I'm certain this probably happens as the main constraint is aircraft mechanic labor and you don't want them working 80 hours one week and 20 the next because you had a cluster of C-checks, however AWS does not require this level of micromanaging (thankfully).

BD

  • Former member
Re: C-check scheduling
« Reply #3 on: September 18, 2013, 09:39:34 PM »
If you take a step back, you will realize how ridiculous this is.

Instead of paying for C-checks when they are due, you want to pay for them before they need to be paid for, which actually hurts your cash flow at the macro level because you're paying for unnecessary maintenance.

Statistically, the frequency of C-checks is a Poisson distribution and subject to the central limit theorem.  Which basically means that those "clusters" of C-checks will start to converge on the theoretical mean.  Or in less technical terms, the more aircraft you add to your fleet the less variation you will experience in weekly cash flow due to C-checks.

So as it stands today, the problem is only a problem if you have a small fleet, and if you have a small fleet you should be able to use the existing features to "space out" your C-checks, which is still a losing proposition because you're giving up free cash flow today to pay for unnecessary maintenance versus using future cash flow to pay for required maintenance.  If you add in the time-value of money, it becomes even more of a no-brainer.  If you're really worried about these short term fluctuations, the solution is to always have $1 million in cash on hand and treat that as your $0 level so there is always a reserve for C-check expenses.

IRL I'm certain this probably happens as the main constraint is aircraft mechanic labor and you don't want them working 80 hours one week and 20 the next because you had a cluster of C-checks, however AWS does not require this level of micromanaging (thankfully).
Come on...why use such a tone?  :-\

Probability does not equal actual instance...that scientific Poisson Distribution nicely piled much of my c-checks into one part of the year (long tails anyone?).  :P   

I fully understand what you say about the extra cost to doing so.  Yes, there is the time value of money related to doing maintenance earlier than technically necessary.

Your suggestion of reserving $1M has an opportunity cost as well, btw.  I think that matters more.

That $1M means approx one a/c and two to three routes (ymmv for other airlines/airports/aircraft).  That's a recurring weekly profit stream of, minimally, $20K+/- (less whatever allocation of costs that don't show up on my aircraft page) vs a one time cost of $2K per each week of shifted C-check (C-check cost/50 weeks - again, ymmv by a/c), plus whatever the time value calculation of that one time charge would be.  In high growth mode, that is a pretty important distinction.

So yes, because of an artificial constraint, the bottom line choice is either slowing down my growth a bit and sitting on a pile of cash, or using that cash, but risk missing an opportunity to conduct a transaction because I cannot schedule my time around the game's time. 

I tried to "correct" the imbalance by attempting to smooth out the checks, but I found that it merely doubles down on issue of scheduling around the game, as it has to be done in "real time".  I've moved several of the worst occurrences so it is better now, but it is far from ideal.

This is by far my overriding consideration for this request - the ability to fit this aspect of the game better to my schedule as a player.  To me, that is worth something, even if it means my airline is hit with the extra cost in the one time transition.


Offline LemonButt

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Re: C-check scheduling
« Reply #4 on: September 18, 2013, 11:13:51 PM »
Not trying to be a p***, but it is ridiculous.  I'm not sure if you know this, but C-checks will be performed if you are in the red, as long as your not DEEP in the red, so you could easily operate your airline (assuming it is profitable) with a $0 cash balance and still have all the checks performed.

At the end of the day, you want to spend money before you have, which is fine, but hurts you more than it helps you.  And yes, that Poisson distribution has tails on both ends and it will happen where you have an exceptional number of C-checks at one time, but as your fleet size increases all of that gets smoothed out.  It's for all these reasons it makes no sense to spend money you don't have to on maintenance you don't need yet.

BD

  • Former member
Re: C-check scheduling
« Reply #5 on: September 19, 2013, 01:45:34 AM »
... ridiculous....not sure if you know this, but...
Aw man!   ???  

I'm left guessing what your intent is, so will assume you really don't intend to mean anything derogatory by it (not sure what p*** means which may be a clue that we are getting our signals crossed).  ;D

...C-checks will be performed if you are in the red, as long as your not DEEP in the red, so you could easily operate your airline (assuming it is profitable) with a $0 cash balance and still have all the checks performed....spend money you don't have to on maintenance you don't need yet.
I know that maintenance generally still occurs in minor red status, thanks.

The issue is not about being able to afford C-checks and being in the red.  

The airline is profitable and covers the c-checks just fine.  If not so, I would not be looking to pay them earlier than I have to.

At the end of the day, you want to spend money before you have, which is fine, but hurts you more than it helps you.  
Spend money on c-checks before I technically have to, yes.  But not because I want to.  

It is because given the choice of sitting permanently on $1M, as you suggest, or using it, I chose to use it (available cash) to invest to generate revenue (reflecting my greater priority on growth).  

However, that choice means that I must time my IRL interaction with the game because of the timing of POSITIVE cash balances which occur towards the latter part of a game week and varies from week to week.

Where c-checks come into play is that they can create an impediment to that timing.  If they could be smoother, I could keep an optimal level of capital in play vs having to manage around them with some kind of reserve however short lived.  

The cost of that smoothing would be less than the NPV of the revenue stream, which I think I logically demonstrated in my prior post (the difference seems vast enough that the cost of shifting c-check schedules looks like pennies).  But, I could be missing something, if someone could non-offensively point it out, I'm quite willing to admit error.  :laugh:


Notwithstanding all that...


It comes back to a compromised choice because of an unintended constraint in game play.  

Not having the flexibility to schedule c-checks means I must either carry a larger airline cash balance to cover the "waves" ...OR... I must risk not being able to meet opportunities because my IRL schedule does not permit me to be active in the game at the time they present themselves.  

It is this non-game-financial, IRL consideration that motivates this request.  

It is not a choice I WANT to make, but one that I must, given the constraints of functionality in the game.  

...but as your fleet size increases all of that gets smoothed out.
According to the theory, on average, yes.  However, the average is made up of several observations/instances.  It is instances we live with, not averages.

I would think that 50 should be a good number for an average spread of closely even across a year, if it were random (I could sub-optimise my aircraft selection at lease time to force a smoother c-check schedule, but that would have other costs).  After some nudging, I now have them roughly equal by quarter and not bad monthly.

Still, even if they fell close to the average, I'd expect month to month and week to week variation, and it still seems desirable to smooth them out, for my reasons stated above.


Where to from here...


I doubt anything will be done soon, as this has been open for some time, so I have to make my choices and play on.  ;D

That said, not sure I'll go further than what I have for now, given the hassle and that it is time to diversify aircraft, perhaps to something new.

« Last Edit: September 19, 2013, 12:36:56 PM by BD »

5teve

  • Former member
Re: C-check scheduling
« Reply #6 on: September 21, 2013, 08:02:37 PM »
BD I agree that a C-Check Schedule would definitely enhance the game.

Personally I would take your idea and add a little to it. Perhaps a separate 'Schedule' could be created to allow zero touch C-Checks without affecting operations. For example sake I will use a nice round number of 24 planes.

If I have a fleet of 24 of aircraft of the same 'family' eg A32x or 737NG's and a C-Check takes 2 weeks. This means 23 aircraft will be in service at any given time and 1 on C-Check.

A screen that allowed me to plan C-checks on a 12 month basis and also allowed automatic assignment of my 'spare' aircraft to replace the one going into maintenance would be very handy. Essentially it would enable planning of C-Checks for years in advance and mean we wouldn't have to worry about manual intervention to ensue routes are unserved when planes hit the hangar.

Steve

exchlbg

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Re: C-check scheduling
« Reply #7 on: September 22, 2013, 12:28:20 PM »
Automatic scheduling  was not part of that request and is not possible for far more reasons than you just mentioned.
That was discussed here before many times.
Although C-checking before its due would mean more costs, there are reasons esp. for smaller airlines to do so. Not everybody gets to the stage of flying a few hundred birds off 4 bases.
It even would be closer to reality to consider manpower, space and cash management in scheduled checking.  
Would be nice to have the opportunity to set a date for checking actions (on individual aircraft page). In a second step an individual pre-setting of every schedule moving action (on schedule page) would be nice,not only to cover checks with spare planes but also to guarantee a smooth transition from old plane leaving your airline to a new one if you are not online at that special time.Plan time
could be limited to next 30 days by giving the option of chosing the next matching date number (1-31).
« Last Edit: September 22, 2013, 12:53:37 PM by exchlbg »

Offline Sami

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Re: C-check scheduling
« Reply #8 on: September 24, 2013, 06:25:25 PM »
So basically just a manually operated thing that sets the C check to be performed in a future date?

UI-wise easy to put to maintenance actions page, technically would require some work.

brique

  • Former member
Re: C-check scheduling
« Reply #9 on: September 25, 2013, 12:31:50 AM »
I'd be happy with just a simple 'perform c-check on date xx;xx;xx' function on the maint page for an aircraft : imagine it would also require a background check to ensure the date is valid and not after the otherwise due date.

that would go a long way to smoothing out cash-flow and schedule disruption for smaller operators working on tighter margins.

'auto-re-scheduling to a spare ' of aircraft in maint is a nice idea, but not vital, imho : if you could pre-plan the fleet c-check skeds, then manual swapping would become much easier anyway or just leave it to do its thang, as prefered

BD

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Re: C-check scheduling
« Reply #10 on: September 25, 2013, 07:31:47 PM »
I'd be happy with just a simple 'perform c-check on date xx;xx;xx' function on the maint page for an aircraft : imagine it would also require a background check to ensure the date is valid and not after the otherwise due date.

that would go a long way to smoothing out cash-flow and schedule disruption for smaller operators working on tighter margins.

'auto-re-scheduling to a spare ' of aircraft in maint is a nice idea, but not vital, imho : if you could pre-plan the fleet c-check skeds, then manual swapping would become much easier anyway or just leave it to do its thang, as prefered
Agreed...main point is the ability to move the date - and no limit on the date other than it must happen within a 12 month cycle.

Thanks for the updates by everyone.  ;D
« Last Edit: September 25, 2013, 07:36:15 PM by BD »

Offline eleytheria

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Re: C-check scheduling
« Reply #11 on: October 17, 2013, 01:17:33 AM »
I came here looking for exactly this.

My current situation: my fleet is made of a 21 planes in one base and 14 in a second one. I usually have an extra spare plane for every 24 so that when one goes in c-check I can keep flying the routes by moving the schedule on the spare plane(s).

I have received a new plane every two weeks, which means that with 24 planes, I have a c-check every two weeks. Smooth, except for used planes that I have sometimes gotten by the pair on the same day.

I don't login regularly enough to do keep it up and sometimes I find myself with 2 expired checks+1 expring that day. All the sudden I have to run 3 c-checks at the same time, with only one spare plane.

If I could schedule the c-check on a given date I would move the schedule to my spare plane and set the c-check to run at a set date.


Example:

AAA c-check 01/01
AAB c-check 15/01
AAC c-check 30/01
XXX spare plane

What I usually do: on 31/12 I move AAA's schedule to XXX and run AAA's check. I will than move the schedule back to AAA and repeat the process on 14/01 with AAB and on 29/01 for AAC. With more aicrafts I do the same but with two spares.

If I don't login for 2 weeks, I will find myself with AAB and AAC's check at the same time, for example, defeating the whole purpose. Instead, if I could schedule the c-check, I would be able to set it up before logging out. And if I have a cluster, I can spread it back again by anticipating the c-check.

I probably did a horrible job describing it, sorry!


Offline eleytheria

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Re: C-check scheduling
« Reply #12 on: October 17, 2013, 01:18:33 AM »
I'd be happy with just a simple 'perform c-check on date xx;xx;xx' function on the maint page for an aircraft : imagine it would also require a background check to ensure the date is valid and not after the otherwise due date.

that would go a long way to smoothing out cash-flow and schedule disruption for smaller operators working on tighter margins.

'auto-re-scheduling to a spare ' of aircraft in maint is a nice idea, but not vital, imho : if you could pre-plan the fleet c-check skeds, then manual swapping would become much easier anyway or just leave it to do its thang, as prefered

this exactly!

FORSBERC

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Re: C-check scheduling
« Reply #13 on: October 24, 2013, 09:12:21 PM »
A GUI would be nice to display the up and coming C-Checks. This should also apply to D-Checks since they are MUCH more time and cost intensive.

It would also be nice to have a maintenance cost forecast for a filterable amount of time. On this maintenance scheduling screen, there should be the ability to reschedule C-Checks and then see the checks move in "real time" to match the changes. You could do something similar to the aircraft scheduling screen, where you see 12 months instead of the 7 days, with the horizontal bars indicating maintenance of aircraft.

Offline LemonButt

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Re: C-check scheduling
« Reply #14 on: October 24, 2013, 09:39:26 PM »
A GUI would be nice to display the up and coming C-Checks. This should also apply to D-Checks since they are MUCH more time and cost intensive.

You mean like this? ;)

FORSBERC

  • Former member
Re: C-check scheduling
« Reply #15 on: October 25, 2013, 03:59:43 AM »
No, I mean for the whole year for C-checks and make 12 separators for each month. For D Checks, you could make a line for 7 years, and 7 separators for each year. I am no graphic artist, nor am good with any image editing software, otherwise, I would post a sketch of what I mean. But the similar layout to the aircraft scheduling page would be awesome, very clear, and offer a nice design carryover to allow ease of use for everyone.

The picture you posted is an awesome illustration of why something simple is necessary for easily planning and scheduling heavy checks. That screen is an information overload and really isn't all that useful for planning since it is simply showing the next month.

Zoom

Offline Sanabas

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Re: C-check scheduling
« Reply #16 on: October 25, 2013, 07:05:22 AM »
I just go to aircraft --> my aircraft --> maintenance view, then sort by D check to see if I have any coming up in the next year or two, meaning I should probably decide whether to do the D-check or switch off the lease renewal.

BD

  • Former member
Re: C-check scheduling
« Reply #17 on: October 25, 2013, 02:05:05 PM »
A GUI would be nice to display the up and coming C-Checks. This should also apply to D-Checks since they are MUCH more time and cost intensive.
I, too, would like to see them on the Upcoming section in the Aircraft summary page.  Perhaps they don't show up there for me, as I turned off auto D check.

I DO get a message about two months in advance on D checks (not sure if that is because I turned auto off), which is a reasonable time-frame to take action in response.

The Aircraft summary page only seems to give a 30 day heads up, which is cutting it tight IRL for gameplay purposes. 

As mentioned just above, IMHO, it really is necessary to regularly survey the Maintenance view to give oneself a long runway for planning around several D checks (logically, the larger the airline, the more critical this becomes).

FORSBERC

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Re: C-check scheduling
« Reply #18 on: October 25, 2013, 06:22:19 PM »
I just go to aircraft --> my aircraft --> maintenance view, then sort by D check to see if I have any coming up in the next year or two, meaning I should probably decide whether to do the D-check or switch off the lease renewal.

That is good if you want to sort through the numbers. But it is not very convenient for for determining HOW many aircraft will be D-Checking at one time or if there are any gaps in the D-Check schedule. A visual depiction would help out a lot.

Offline Kazari

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Re: C-check scheduling
« Reply #19 on: October 27, 2013, 01:52:11 PM »
It's nice to know that my FOUR-year-old post is finally getting some traction.  ;)

Sometimes it just takes a little time, I guess.

 

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