But the two protagonists have still racked up 1,360 sales between them this year, pushing their combined backlog up by a further 200 aircraft.
Total net orders for year stand at 1,360, which is 20% down on the first nine months of last year. Some 398 net orders were placed in the third quarter, compared with 522 in the same period last year.
Airbus has extended the lead it held at the six-month mark, with 737 orders against 623 of its rival. Driving its success is the A330, which has already accumulated 138 orders in 2008, just 12 shy of its sales in the first nine months of 2007.
Airbus has restructured its orderbook during the third quarter, finally eliminating the Iraqi A310 order which was signed just before the first invasion of Kuwait in 1990.
The Kingfisher A340-500 orderbook has also been revised, with seven of the 10 orders being removed (two going to Arik Air of Nigeria), and the Indian airline's A330 orders have been increased by five to 20.
Boeing's Q3 net orders fell almost 60% on last year - which was a particularly strong quarter - to 148. Significantly, the airframer saw its first lean quarter for 787 sales, with orders standing at a net minus one as a result of Azerbaijan Airlines reducing its order for three 787-8s to two.
Remarkably, it was Boeing's old-timer, the 767, which was its best-selling widebody, with 20 orders secured - primarily the capacity-bridging deals with 787 launch customers All Nippon Airways and Japan Airlines (the latter officially still "undisclosed").
Combined deliveries rose just 3% on the first nine months of 2007 to 674, as the Boeing industrial dispute kept its shipments flat. Airbus output has increased by 6% to 349 aircraft.
Boeing, which had averaged 39 deliveries a month during the first nine months, delivered just 12 aircraft in September in the wake of the production stoppage. Its three-month delivery tally declined to 84 from 109 in the same period last year.
Despite the sales slowdown, the airframers still grew their backlog by 200 aircraft to over 7,530 aircraft as orders continue to outpace deliveries by a factor of two to one.
The share of the backlog remains well-balanced, with Airbus having edged into a slight lead from the position at the end of June.