C series CS100 GTF engine failureMay 2014 would not be recorded in history of civil aviation as a great month for Bombardier C series family.First problems came from commercial side and sales. Air Canada have announced they are going to keep 25 Embraer 190 jets in their service which were otherwise targeted to be replaced by C series aircraftAnother blow came from the single largest customer Republic Airlines has put a hold on order of 40 larger 138 seat CS300 Republic will still remain the largest single customer with 40 of smaller CS100 on firm orderOn top of that on the 29th of May first CS100 flight test aircraft FTV-1 has suffered engine failure on the ground. The event happened according to some inside information on the ground and represents so called uncontained failure which means that the parts of the failed engine exited the casing of the engine and caused damage to the surrounding aircraft structure. The consequences for the already delayed C series program would be most likely at least further delays. The other manufacturers would need to look at this as this engine is used in new projects by Embraer (E2), Mitsubishi (MRJ), Comac (C919), Irkut (MS21) and Airbus (A320NEO family). Excluding Airbus where this engine is one of the two options, for other quoted manufacturers the engine Pratt and Whitney geared turbofan (GTF) is the only engine and the total order book for this engine stands at 5500. In contrast to the CS100 aircraft which is in flight testing development phase, GTF achieved certification by Transport Canada on 20th February 2013 so this event represents in service event for the engine.According to unnamed insider sources the engines on FTV-1 are not standard engines but pre-series standard. We shall see in coming months if this statement has made any difference to the event or not.There are however some benefits from the event. Although for the engine manufacturer PW this can not be good news, the engineers from the airframer Bombardier would now have lots of data to compare their uncontained engine (rotor) failure models. The UE(R)F models serve to protect the aircraft of the rare events of particular risks where the aircraft structures and systems must be designed in such a way to protect safe flight and landing in such rare cases. What is important is that the common causes faults are avoided. Namely in this case the engine debris should not damage or knock-out some of the flight critical systems. Typically aircraft design engineers would draw volumes (cones) in which the contained engine debris could eject the engine. Then they would check if the planned trajectories would intersect with any of the vital systems or structural parts. If there would be any intersection with the vital parts, they would either be removed, shielded or doubled in the further redesign when such checks take place. Taken into account that this event happened on the ground, there would be lot of evidence in the small area, collectable and available to Bombardier engineering teams so they can compare if the assumptions they have taken coincide with the reality. So this event could be viewed as live uncontained engine rotor test. It could be even potentially be used as part of the evidence for certification that some of the systems and structures were properly shielded.What seems as risk for someone may be an opportunity for someone else.References:(http://www.bloomberg.com/news/2014-05-15/air-canada-to-keep-25-embraer-jets-in-blow-to-cseries.html).(http://www.flightglobal.com/news/articles/republic-puts-off-decision-on-cseries-order-399322/).(http://en.wikipedia.org/wiki/List_of_Bombardier_CSeries_orders).(http://online.wsj.com/news/article_email/new-bombardier-jet-suffers-major-engine-failure-1401475483-lMyQjAxMTA0MDMwMDEzNDAyWj)