Alstom says Paris RER B delays will be fixed ‘provided CAF deliver’

Alstom has defended itself after fierce criticism from Paris transport authority Île-de-France Mobilités (IDFM) over fresh delays to the new MI20 trains ordered for the key RER B line. Set to enter service up to four years later than pledged, the French manufacturer points to its new timetable for test-train deliveries — but warns RailTech that progress still depends on its Spanish consortium partner CAF delivering on time.

Late last month, Paris transport authority Île-de-France Mobilités (IDFM) issued a sharp public warning to Alstom, accusing the manufacturer of “unacceptable” delays to its MI20 fleet. The €2.5 billion contract for 146 trains, signed five years ago, was meant to renew rolling stock on the RER B route, a key commuter line in the French capital that carries more than one million passengers daily. The new trains had originally been scheduled to arrive this year.

That deadline has now been extended by at least three years. An expert review commissioned by Paris’ operators and cited by IDFM warned that because of “a risk of industrial failure,” the first MI20 trains might not enter service until September 2029. It added that the proposed delivery timetable for the flagship fleet was “neither robust nor credible.”

During a tense board session in late September, IDFM president Valérie Pécresse reminded Alstom that the regional authority was its “largest customer” and demanded concrete action to bring the project back under control, including a revised industrial strategy and schedule by year’s end. Its key demand: that the first MI20 trains enter service by 2028, not 2029.

Several weeks on from that very public reprimand, Alstom tells RailTech it is working to meet its client’s expectations, stating that five test trains “would be made available next year” — a crucial step that would finally allow dynamic testing, safety certification, and validation of the fleet to begin. Without those trains, the rest of the delivery schedule is little more than a projection on paper. But with the MI20 long dubbed by insiders as a “cursed dossier,” it’s little surprise that Alstom is keen to stress the delays are not its fault alone, but a shared challenge — born of a partnership it once tried to escape — with CAF.