The shape of the distribution
When we compute the difference between the moment a leg appears on our snapshot and the leg's own departure time, the result is not a smooth curve. It is a heavily right-skewed distribution with a long tail into the future and a sharp cliff on the near-term side. The median lead time in our June 2026 sample sits at roughly 62 hours — a little over two and a half days — and more than 65 percent of the entire feed carries a lead time of less than 72 hours. Anything more than two weeks out accounts for under 10 percent of the sample. The market is, in a very literal sense, a short-cycle inventory market.
The reason for the shape is operational. An operator does not know a leg is going to be empty until the contracted flight ahead of it is confirmed and paid, which typically happens between five and ten days before the primary trip departs. Once that confirmation lands, the operator's dispatch office looks at the aircraft's calendar, identifies the repositioning legs that will follow, and pushes them onto the public feed. The interval between the primary trip's confirmation and its departure is what sets the outer bound of the empty-leg lead time — and that bound is almost never further than two weeks.
Why the 48-hour cliff exists
Within the general skew there is a specific, sharp discontinuity at the 48-hour mark. Legs with more than two days of lead time are common; legs with less than two days are dramatically more common, and legs with less than 24 hours account for a striking share of the total. The reason is that operators aggressively push down inventory as departure approaches. A leg that is still unsold at the T-48 mark is essentially guaranteed to fly empty; the operator has already committed the crew, filed the flight plan and paid the handling fees. Every additional discount from that point is pure marginal revenue against a fixed cost.
Two days before departure, the operator's incentive flips. The leg is going to fly regardless. Any price above zero is a win.
This is the moment when the headline 75-percent discount the industry advertises actually appears in the wild. A leg posted at T-96 hours will typically carry a discount of 20 to 30 percent versus the equivalent full-charter quote; the same leg re-listed at T-24 hours can settle 50 to 70 percent below the original charter price, particularly if the operator's algorithm detects that the leg has received no serious enquiries. The cliff is not marketing; it is the exact point at which the operator's revenue-management logic switches from margin protection to loss mitigation.
What this means for the buyer
If you are shopping the feed manually, the practical instruction is unsentimental: check often, in short windows, close to your desired travel date. Checking a public empty-leg aggregator two weeks before a trip will surface at most 30 percent of the legs that will eventually exist on your corridor, and almost none of the deeply discounted ones. Checking the same aggregator at eight in the morning on the day before travel will surface everything the market has to offer, priced at its softest. The half-life of a good deal is measured in hours, not days.
For a buyer who cannot spend the week refreshing a feed, the correct workflow is an alert. Our own empty-legs page and the alert form embedded in it exist precisely because the market rewards being the first serious enquiry on a newly-posted leg. An alert delivered within minutes of a leg going live is worth more than an alert delivered the following morning; a broker who reads the feed at seven in the evening and calls back at nine is competing with buyers who received the same leg at 07:03. The economic value of speed on this market is far greater than the economic value of route or aircraft flexibility, and it is not close.
The narrow window that isn't a cliff
There is one meaningful exception to the general lead-time pattern, and it is a corridor phenomenon. On heavily seasonal routes — the Northeast US to Nantucket in July, the DACH region to Sylt in August, London to Ibiza on any summer Friday — operators publish legs earlier because they know the corridor will absorb the inventory even at low discounts. A Nantucket leg posted at T-9 days is genuinely likely to sell; a Van Nuys deadhead posted at T-9 days almost certainly will not. Reading the lead-time distribution by route is therefore as important as reading it in aggregate: some corridors reward patient shopping; most do not.
The other exception is the ultra-long-range segment. Legs on Global 7500s, G650s and Falcon 8Xs tend to appear earlier because the operators of these fleets manage their scheduling on longer horizons and because the pool of buyers willing and able to book a heavy jet on 48 hours' notice is much smaller. If you are shopping for a heavy jet on a transatlantic corridor, the feed will show you meaningful supply seven to ten days out — and the discounting behaviour close to departure is muted because there is no crowd of last-minute retail buyers to drive the price down.
Reading the timing correctly
The lead-time distribution is the piece of empty-leg data that a first-time buyer is most likely to get wrong, because the intuition from every other travel market — book early, save money — inverts on this one. Empty legs are a distressed-inventory market layered on top of a scheduled repositioning market, and distressed inventory rewards patience within the 72-hour window and punishes it outside. The right workflow is to identify your corridor, set an alert, and be ready to move within an hour of the notification landing in your inbox. Any workflow that begins with a two-week horizon and a browsable aggregator will systematically deliver worse economics than one that begins with a live alert at T-36 hours.
For our own charter desk, the 48-hour cliff is one of the operational realities that shapes the whole business. Our AI-guided search re-scans the feed every few minutes; our alert system pushes new legs to subscribers within seconds of publication; our brokers are trained to close on high-value legs inside a single working hour. None of that is a feature; it is the minimum table stakes for participating seriously in a market whose median lead time is 62 hours and whose best economics live inside a window of 24.