Airbus and Boeing are each observing 7,000 delivery milestones of a different kind this week. Airbus is celebrating the delivery of its 7,000th aircraft, an A321, while Boeing will hand over the 7,000th 737.

The A321 was delivered on Dec. 12, just under two years after Airbus passed the 6,000th delivery milestone with the handover of an A380 to Emirates in January 2010. The event for the European manufacturer comes as Boeing prepares to hand over the 7,000th 737, a 737-800, to Emirates low-cost subsidiary FlyDubai. The aircraft is in final pre-delivery completion and will be officially presented to the customer this week, says a Boeing spokeswoman.

The handover of the A321 to US Airways, currently operator of the world’s largest Airbus fleet, took place at the Airbus Hamburg site in Germany. The delivery also marks the progressive production ramp-up across the single- and twin-aisle product lines which, in the case of the A320 family, is set to rise to 42 units per month late in 2012. Boeing also is in the midst of a historic production ramp-up for the 737, which will rise to 35 units per month in 2012 and 42 per month in 2014.

From its initial A300B delivery in 1974, it took Airbus 19 years to deliver the 1,000th aircraft, an A340-300 for Air France in 1993, and a further six years to hit the 2,000th delivery in 1999. Three years later, it hit the 3,000 mark, followed by the 4,000th aircraft in 2005. The 5,000th aircraft, a Qantas A330-200, was delivered in December 2007. Including heritage McDonnell Douglas products, Boeing has delivered more than 17,900 jet airliners since the late 1950s and is set to pass the 18,000 mark early in 2012. Overall unfilled orders currently stand at more than 3,530, of which 2,192 are 737s.

By the end of the year, Airbus says US Airways will operate a fleet of 93 A319s, 72 A320s, 63 A321s and 16 A330s. The airline also has firm orders for an additional 58 A320 family aircraft, eight A330s and 22 A350 XWBs on backlog. Overall, more than 8,200 A320s are on order with over 4,900 delivered.