Aircraft Backlog and
Delivery Slippage Tracker
Airbus and Boeing hold about 16,150 firm commercial aircraft orders. At the delivery rates they are actually achieving that is a little over ten years of work; at the rates they say they will reach by 2027 to 2029 it is about eight. Boston Warwick publishes both numbers monthly.
Every published backlog figure quotes years of cover at a production rate that has not been achieved. This tracker publishes two numbers side by side every month: cover at the rate the manufacturer is currently delivering, and cover at the rate it says it will reach. The distance between them is the whole of the analysis, and it is not published anywhere else in one place.
A backlog is not a delivery schedule. It is a claim on a production system, and in 2026 that system is running well below the rates presented as targets.
Backlog, rate and cover
Data to end July 2026. Cover is backlog divided by annual output, which ignores new orders, cancellations and mix, and is stated on both bases.
| Programme | Firm backlog | H1 2026 deliveries | 2026 target | Stated rate path | Years of cover at current rate | Years of cover at stated rate |
|---|---|---|---|---|---|---|
| Airbus total | 9,352 | 351 | about 870 | above 1,100 a year by 2029 | 10.7 | 8.5 |
| A220 | 574 | 44 | within 870 | rate 13 a month, 2028 | 6 to 7 | 3.7 |
| A320neo family | 7,574 | 271 | bulk of 870 | 70 to 75 a month, end 2027 | 10.4 to 12 | 8.3 |
| A330neo | 334 | 10 | within 870 | rate 5 a month, 2029 | high teens | 5.6 |
| A350 family | 870 | 26 | within 870 | rate 12 a month, 2028 | about 8 | 6.0 |
| Boeing total | about 6,800 | 314 | 645 to 660 consensus | 737 to 47 a month 2026, 52 in 2027 | about 10.5 | not stated as a group |
| 737 family | 4,888 | 243 | 500 MAX | 47 a month 2026, 52 in 2027 | 10.0 | 7.8 |
| 787 | within total | 40 | 90 to 100 | rate 10, subject to engine supply | high single digits | lower |
| Embraer commercial | about 319 | within guidance | 80 to 85 | executable on current evidence | about 4 | about 4 |
Scroll the table sideways on a narrow screen. No column is hidden.
The two numbers that matter this month. Airbus delivered 418 aircraft through July. Reaching guidance of around 870 requires 452 in five months, about 90 a month, against 67 in July and an estimated 49 in August. A fourth quarter sprint is the entire plan. The realistic band is 820 to 850. Boeing delivered 367 through July against a consensus of 645 to 660, which is a less demanding second half.
Where the constraint actually sits. The A320 family assembled at a cadence consistent with the mid 50s a month in the first half and handed over at 45. Ten A320 final assembly lines are already configured for rate 75. The binding constraint is engine availability, not floor space, which means the delivery rate is a function of somebody else's shop capacity.
The mix point that most commentary misses. About 5,677 of the 7,574 A320neo family backlog is A321neo. The production difficulty is not building A320neos. It is building A321neos at rate, with the longer fuselage, the heavier variants and the rear centre tank on a subset. Any rate discussion that treats the family as homogeneous understates the constraint.
The constraints, tracked
| Constraint | Status, September 2026 | Direction | Resolution window |
|---|---|---|---|
| PW1100G on the A320neo | Peak of about 650 aircraft on ground. Still the Airbus rate limiter. Advantage first shipsets delivered 2026. Second quarter repair output up 43 per cent year on year, turnaround down 23 per cent | Improving slowly | Manufacturer claims low single digit aircraft on ground late 2026. Full durability recovery end of decade |
| PW1500G on the A220 | Aircraft on ground 2 to 3 per cent of the sub fleet against about 17 per cent a year earlier | Improving | End 2026 for the residual |
| PW1900G on the E2 | About 1 per cent against a 22 per cent peak in March 2025 | Largely cleared | End 2026 |
| CFM LEAP | Groundings near zero. A rate constraint at the top end of A320 and MAX output rather than a grounding event | Stable | Not the 2026 headline |
| 737 fuselage supply | Boeing closed the acquisition of its fuselage supplier in December 2025. A new aft fuselage quality issue was flagged on 12 August 2026, described as not an immediate safety of flight matter, with inspection and repair being written | Fragile | Quality stability is a 2026 to 2027 test, not a completed event |
| MAX 7 and MAX 10 certification | Both uncertified in September 2026. Industry inventory held 116 finished narrowbodies at end August, primarily MAX 7 and MAX 10 airframes requiring significant post production rework | Slipped once in 2026 | Deliveries talked for 2027 |
| 777-9 certification | First delivery now 2027 against an original 2020 entry into service. Cumulative pre tax programme charges exceed $15 billion | Behind two uncertified MAX variants in the queue | A further slip into late 2027 is the base case, not the bear case |
Scroll the table sideways on a narrow screen. No column is hidden.
There is no published series for average delay by order year. Three proxies are worth tracking and are carried in each issue.
Aircraft that exist but cannot be delivered. 116 finished narrowbodies sat in industry inventory at the end of August, most of them airframes of two uncertified variants. That is slippage that can be counted on a ramp: the aircraft is built, the certificate is not.
Contractual slip after a reset. One large lessor discloses that once contractual dates were reset, subsequent slips have generally run one to two months, with an explicit warning that both frequency and length could increase. Cancellation rights in that style of purchase agreement typically crystallise twelve months past the original contractual date.
Customer side accumulation. One United States carrier recorded 81 aircraft contractually committed for 2024 and 2025 that had still not arrived at the end of 2025, carried as $1.7 billion of the following year's capital expenditure line. That is the cleanest public measure of what slippage does to an operator's balance sheet rather than to a manufacturer's press release.
Delivery slippage stopped being a sequence of single events, the grounding, the delivery halt, the tank certification, and became a feature of the production system. The consequences are more durable than the manufacturer narratives that surround them.
Mid life lease rates stay firm because operators who cannot get new aircraft keep the ones they have. Retirements are deferred, which puts additional shop visits onto earlier generation engines that were supposed to be leaving service. Route launches quietly do not happen. And the backlog figure itself is softer than it looks, inflated by aircraft that will be converted to other variants, deferred, or cancelled without announcement, and by variants whose certification dates keep moving.
Backlog is firm commercial orders. Airbus publishes a clean commercial order book. Boeing's published figure is sometimes quoted net of accounting adjustments for orders unlikely to be delivered, and this tracker uses the compilation that strips those, so that the two manufacturers are comparable.
Cover is backlog divided by output and ignores new orders, cancellations and mix. It is a measure of depth, not a forecast of when any particular aircraft arrives.
Where a figure is directional rather than published, it is labelled. Where a manufacturer states a rate target, the date attached to that statement is carried with it, because those dates move and the movement is part of the record.
Sources are the manufacturer order and delivery filings and half year results, third party monthly compilations used as a cross check, and company guidance quoted with its date.
Both tables are published as a single CSV file so that every figure and every derived column can be checked against the manufacturer releases.
Download issue 01 as CSV ↓Last updated: 2 September 2026. Next issue: first week of October 2026.
Backlog depth is a fleet planning input.
Boston Warwick advises airlines, lessors and investors on what a delivery position is actually worth once the rate assumptions behind it are tested.
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