The Reserve Aircraft

A reserve earns nothing until the day it saves a rotation. How the substitution engine picks a replacement, what happens to bumped passengers, and when the idle tail pays for itself.

A reserve is an aircraft you deliberately pay to do nothing. It sits parked, unscheduled, accruing lease payments and upkeep with zero revenue, until a rotation breaks and it saves your week. Whether that trade is worth making is one of the better fleet-planning questions in the game, and the answer turns on mechanics worth knowing precisely.

What counts as a reserve

On an aircraft's page you place the tail in reserve. A reserve is unscheduled by definition; the game will not let you flag a tail that still has flights assigned, and a reserve stays put until it is needed or you release it. The Fleet page counts your reserves and the Operations board tags them, so you always know where the spares sit.

Four ways a rotation breaks

A reserve steps in when a flight is about to be lost: a technical failure on a poorly maintained tail, an assigned aircraft out of position, a delay long enough that the flight would be scrapped, or a heavy check about to ground a tail with flights still on its schedule. In every case the spare must be parked at the right airport, healthy, and free of its own schedule. If no reserve qualifies, the normal bad outcome happens: cancellation, passenger compensation, and an image hit.

Planned heavy checks are the exception some worlds allow. Because the hangar date is known in advance, a spare parked at another airport can position in on a non-revenue ferry, provided it can land and complete its turnaround before the first affected departure. The ferry burns real fuel, and each tail gets at most one positioning move per day. Sudden failures get no such grace. There is no lead time when the flight is leaving now, so the spare must already be on site.

How the substitute is chosen

Worlds that enable full substitution (off by default; check yours) run a capacity-fit match. By default only the same aircraft type qualifies, with a total seat count between 80% and 130% of the broken tail's cabin; worlds and policies can widen the net to the same family, the same size category, or any type at all. Every candidate must actually be able to fly all the affected legs, range and runway length included. Among qualifiers, the engine picks the one that bumps the fewest passengers, then the closest cabin size, then the closest relative, then the best condition.

The swap is a genuine role swap, not a loan. The reserve takes over the entire rotation and becomes the line aircraft, while the broken tail becomes your new reserve, emerging from its heavy check healthy or waiting where it stands. A heavy check covered this way cancels nothing and pays no compensation, which makes a well-placed spare the cheapest hangar visit you will ever take.

Worlds without full substitution still honor the simple case: a same-type reserve parked at the departure airport can rescue an individual flight that would otherwise cancel. Heavy checks there simply cancel the flights they overlap.

When the substitute is smaller

It flies anyway, and the overflow is bumped class by class with no reshuffling between cabins. Bumped passengers get their money back plus a compensation premium, 20% by default, and only they hold it against your image; everyone who does fly rates the trip normally. Overflow cargo is refunded at face value.

Mind the accounting. A rescued flight departs on time, so it never appears in your disruptions list; the bill surfaces as passenger compensation on the ledger instead. A quiet ops board and a noisy compensation line can be the same event.

Worlds with cabin reaccommodation enabled soften the bump. Before anyone is denied boarding, overflow passengers re-seat across the substitute's cabins. Economy overflow rides up front for free, an op-up that costs you nothing. Premium passengers squeezed out of their cabin move down instead: they still fly, you keep the fare, you reimburse part of it (half by default), and they remember the downgrade, a milder image hit than a bump. Only passengers who fit nowhere at all are denied boarding.

The arithmetic of a spare

Idle capital against what one grounded rotation costs in refunds, compensation, and reputation: that is the whole ledger. The structural answer is commonality. A fleet built around one type gets far more from its spares, because a single reserve can cover every tail of that type at its airport. Scatter six types across a network and each spare insures a sliver of it; standardize, and one parked airframe stands behind the whole line.

The full substitution rules live at wiki.theplanesim.com.