When International Airlines Group completed the purchase of British Midland International (BMI) from Lufthansa in late April 2012, it presented British Airways with the major challenge of quickly bringing BMI's Airbus narrowbodies into BA's existing fleet.

From May 2012 to January 2013, in what BA describes as “an extremely complex process,” it integrated 11 Airbus A319s, seven A320s and seven A321s from BMI into its fleet. BMI's two A330s were returned to lessors because BA does not operate Airbus widebodies.

The assimilation of all 25 aircraft in just eight months took place alongside BA Engineering's other in-house and third-party maintenance work. While the airline's maintenance needs account for the majority of its workload, the MRO hopes to grow its third-party work to 20% from today's 10-12% by 2015.

In a multidepartmental effort, incorporating BMI's narrowbodies was handled in three stages by BA's engineering arm based at Heathrow Airport, with help from Iberia Maintenance in Madrid and BMI's engineering facility in the East Midlands, England.

“While this added to an already very full program of maintenance, modifications and painting, we were able to perform the entire integration process without affecting the British Airways operation,” says Mark Davison, business development manager at British Airways Engineering.

The first phase entailed transferring the fleet to BA's aircraft operators certificate (AOC)—requiring mostly safety, flight-deck equipment and software changes—and retrofitting the aircraft cabins. BA kept the Recaro seats on the A319s and A320s, which were recovered in BA colors at Heathrow. The A321s were reconfigured at BMI's East Midlands facility for BA's two-class mid-haul services. Thomson Aero Seating flat-bed seats were installed in the “Club World” business-class cabin and Geven seats in “World Traveller” economy class. Between May and November, 3-4 aircraft underwent a retrofit each month, with a peak of six in October.

The second phase, slightly behind the AOC transfer but concurrent with the first phase, involved repainting the aircraft in BA colors using the PPG Aerospace inter-coat system. BA Engineering completed 14 aircraft, Iberia Maintenance painted seven and BMI finished the remaining three.

BA Engineering's paint bay at Heathrow is large enough to accommodate a Boeing 747 or two A319s at the same time, allowing it to perform the majority of the painting alongside its existing schedule.

The first aircraft was in the paint bay at Heathrow for nine days, starting on May 16, and the 13 others subsequently for as many as seven days. Between June and December, the airline MRO repainted 2-5 per month, with the final aircraft leaving the paint bay on Jan. 2.

The third and final phase was the transfer of the aircraft's Continuing Airworthiness Management Organization (CAMO) records to BA at a rate of around two per week between August and December. “Structuring the integration like this allowed us the flexibility to plan the AOC cutover, cabin retrofit and paint inputs without the complex preparation for the CAMO transfer,” Davison tells Aviation Week. “The CAMO transfers could then be completed toward the end of the process.”

With the BMI fleet now fully integrated, BA has 112 A320-family aircraft in service. The A319s and A320s are flying short-haul routes from Heathrow Terminal 1 to destinations including Dusseldorf, Germany; Toulouse and Lyon in France; Belfast, Northern Ireland; and Leeds, England. The two-class A321s fly to mid-haul destinations including Tel Aviv, Israel; Cairo; Almaty, Kazakhstan; and Baku, Azerbaijan. Heavy maintenance checks on these aircraft will be handled by BA Maintenance Glasgow, Scotland.

BMI's East Midlands base closed after the cabin retrofits and painting were completed.

Tap on the icon in the digital edition of AW&ST for a detailed time line of the BMI fleet integration, or go to AviationWeek.com/bmi