Maintenance limit warnings

What it is

When you create a booking, Syndik8 estimates how much usage it will add and checks that against the asset’s maintenance items, each on the measure it counts. If the booking would take the asset close to, or past, a maintenance limit before that item is due, the booking dialog shows a warning. The aim is to catch “this flight would run the engine past its 50-hour check” at booking time rather than after the fact.

This page is about that booking-time check only. It is separate from the reminders admins get simply from a check’s own status ticking over to due soon or overdue with no booking involved — see Maintenance items: Behaviour rules.

Who sees it

All members see the warning when it applies to a booking they are creating.
At the most serious level a regular member is blocked and pointed at an admin, while an admin can acknowledge and proceed.

Where it appears

In the booking dialog, after you have chosen the asset and the times.
As notifications in the notification centre (see below).
On your own future booking’s screen, while it is at risk (see below).

The three levels

Level	When	What happens
Green	The booking leaves comfortable margin before the item is due.	A quiet note showing how much remains before the item, in the measure it counts (for example, “12.0 flying hrs remain before 50-Hour Check”). The booking proceeds normally.
Amber (Maintenance Approaching)	The booking would leave little margin before the item is due.	A warning card with an Estimated usage field, labelled with the item’s measure (for example, Estimated usage (Tacho hrs)), so you can refine the estimate. Anyone can still create the booking with Create booking.
Red (Booking exceeds a maintenance limit)	The booking would take the asset past the item’s limit.	A regular member is blocked and asked to contact an admin to arrange maintenance. An admin can tick an acknowledgement and use Override and Create.

When the aircraft has no maintenance items at all, there is nothing to check. An admin making a booking that has not started yet is told so in the booking confirmation, with a prompt to set maintenance tracking up; members, and bookings already under way, get no such note.

How the estimate is made

Each check is estimated in the measure it counts. A booking uses different amounts of different measures: an hour and a half on the Tacho might be only an hour of flying. So a check counted in flying hours is compared with an estimate of the booking’s flying hours, and a check counted on the engine meter with an estimate of its meter hours. The card names the measure every figure is in, such as “4.0 flying hrs remain before 50-Hour Check” or “This booking may use approximately 1.5 Tacho hrs”.

The estimate comes from the asset’s recent bookings of a similar length. Each booking counts once, as the total of every flight logged against it, so a trip flown as three short legs counts as the whole trip rather than as one short leg. A booking that has not ended yet is left out, because its later flights may not be logged. Flying hours are read from each flight the same way the aircraft’s own flying-hours total is kept: airborne time where your syndicate records it, otherwise block time, otherwise the engine meter, and nothing for a ground run. A flight that recorded none of those is left out of the average rather than counted as zero. Where there is not enough history, a standard allowance is used instead.

On the amber card you can type your own figure, in the measure the card names, which re-checks the level. The booking records its estimate on the engine meter, so a figure typed in flying hours is converted in proportion: typing twice the flying hours the card estimated records twice its engine-meter estimate.

Notifications

Three notification types come out of this check:

Maintenance Limit Approaching (admins): raised when a new booking came close to a limit, either because the booking dialog showed the member an amber or red warning, or because the server, checking the booking again when it is saved, finds it leaves an hours check with little margin by the same rule as the amber card: 5 hours or less left after the booking, or less than 30% of the hours that were left before it. A booking that was green in the dialog and leaves comfortable margin raises nothing. When the server can tell which check it is, the notice names the member, the aircraft, the estimate, the check and the hours it has left, for example “100-Hour Inspection has 13.0 hrs left, leaving 5.0 hrs after this booking”, and tapping it opens that check. When only the dialog saw it (a check counted in another measure, or one that falls due by date), the notice says the booking check warned it comes close to a maintenance limit, and tapping it opens the aircraft’s maintenance list.
Maintenance Limit Exceeded (admins): raised when an admin overrides the red warning and books anyway. Its title is Maintenance Limit Override. When the booking takes an hours check past its limit, the notice names that check and the hours it has left, and tapping it opens the check; when the red warning came from a date-based limit, it names no check and tapping it opens the aircraft’s maintenance list. If a check a notice names has since been deleted, tapping the notice opens the aircraft’s maintenance list.
Booking May Need Rescheduling (the booking’s owner): raised when a future booking is projected to fall the wrong side of an upcoming maintenance item, usually because earlier bookings will use up the remaining hours first. If the item has been deferred, the projection is against the deferred limit, not the original one. It is re-checked whenever usage is logged, a meter reading is corrected, or a booking on the aircraft is made, approved, moved, cancelled or given a new estimate, so it reflects real readings rather than just estimates. You get it once when your booking first comes into amber or red, and again only if it worsens from amber to red. A figure that changes within the same level sends nothing new. If your booking drops back to comfortable margin, or the check is carried out, a later warning is sent afresh. If you receive it, the maintenance is likely to fall before or during your slot, so check with an admin about rescheduling or the maintenance plan.

Your booking’s own screen shows the current position while your booking is still to come: a Maintenance may affect this booking card. The forecast counts the bookings before yours and your own booking’s estimated hours. In amber, the card shows the hours expected to be left before the check after your booking. In red, it says the check may fall due before or during your booking. The forecast is worked out afresh from the aircraft’s current readings, checks and bookings, so it follows a check being carried out, deferred or added, and a booking being made, moved or cancelled. It updates on the open screen as those changes reach your phone. It is only shown to the member whose booking it is, and only while the app can reach the server. It disappears once the risk passes.

Behaviour rules

The check runs when a booking is created and is based on an estimate of the booking’s usage. The amber card lets you refine that estimate.
Each check is estimated in its own measure, and the card names that measure.
Only the red level blocks anyone, and only regular members. Admins can always override, which records that the booking may exceed a limit and notifies the other admins.
The booking records the level the dialog showed, and the server also judges the booking itself when it is saved, from the aircraft’s readings at that moment. The admins are told on whichever of the two is the stronger. The server has only the booking’s engine-meter estimate and judges hours checks only, so it can disagree with the dialog either way; taking the stronger of the two means a warning the member saw is always passed on, and so is one the member’s device could not see, such as readings recorded since it last synced.
An admin’s override applies to the red warning only. If the estimate is changed so the warning is no longer red, the override is withdrawn and the booking is not reported as one.
The admin who made the booking is not sent either notice, since they have just seen the warning.
The “may need rescheduling” reminder is the only member-facing one. The approaching and exceeded notices go to admins.
These warnings are an informational aid. The Pilot in Command remains responsible for confirming the aircraft’s maintenance status before every flight.