There is jubilation in the offices of Bombardier right now by reason of a huge order made by Delta Airlines for its new C series jets. The deal was announced by both companies on Thursday.

This contract provides a major boost to the airplane manufacturer and its startup C Series aircraft which has experienced sluggish sales among established air carriers. Its deal with Delta includes a firm order for 75 Bombardier CS 100 jets, with options to order 50 more.

The contract also allows Delta to convert some of its orders into the bigger CS 300 variant of the airplane at a later date.

At current list prices, this would amount to $5.6 billion, although these types of deals usually carry provisions for substantial discounts.

The airline company said the CS 100 jets will enable the carrier "to cost-effectively reshape and up gauge its narrow body fleet, providing an improved customer experience and better cost efficiency."

Delta also said that the planes will be deployed on "short- to medium-haul routes throughout Delta's network."

This deal is a benchmark for Bombardier, a Canadian-based airplane manufacturer, as it attempts to break into the large fleets of leading air carriers and supply a niche market for 100-seater airplanes that bigger competitors like Airbus Group and Boeing have ignored.

Bombardier is more than happy with the firm order by Delta Airlines considering that it is their biggest order to date for new jets and it overshadowed the company's dismal first quarter loss on Thursday.

Meanwhile, this order will enable Delta to phase out its 50-seater jets that it leases to regional airlines which fly under the brand of Delta Connection. Additionally, the bigger CS 100 jets consumes less fuel for each passenger, and have extra room for two cabin classes, instead of just one, providing the carrier the chance to up-sell its passengers to business class.