Geared Turbofan Problem on Bombardier CS

[fleigle]

Whoops!, this is going to hurt both programs.

New Bombardier Jet Suffers Major Engine Failure - WSJ (http://online.wsj.com/news/article_email/new-bombardier-jet-suffers-major-engine-failure-1401475483-lMyQjAxMTA0MDMwMDEzNDAyWj)

[DaveReidUK]

"According to two people familiar with the incident, the failure inside the engine was "uncontained" and debris spewed out of its casing."That's not necessarily the definition of an "uncontained" failure (as has been debated on here previously), but if it was then it's bad news. Even if it wasn't, it seems likely to lead to a further delay in CSeries certification/EIS.

[archae86]

both the engine and the airframe were damagedThe airframe part of that sounds a bit like imperfect containment to me.

[barit1]

In my day, a failure was either contained or uncontained. Binary.

Today I hear words like "high energy" and "low energy" uncontained failure.

Pieces of airfoils penetrating the case (and almost certainly the cowl) are regarded "low energy", thus unlikely to bring down the aircraft.(*)

But a rotor disc burst results in chunks with the mass and velocity of a cannonball, putting the enterprise in jeopardy.

* Debris blown out the tailpipe, while not penetrating the case, can possibly damage the tail feathers, and is worrisome from that aspect. :(

[lomapaseo]

"Containment" is in the eye of the beholder

simple words like "must not burst its cases" are a little more descriptive.

Then the conditions of the event are certainly relevant. Such as to whether we're talking high energy multiple particles capable of penetrating a pressure surface behind which are lots of important stuff to fly the aircraft.

Each event must be examined by itself and more importantly combinations such as an uncontainment resulting in :

a loss of flamable fluid

a fire

multiple engine involvement (pilot workload issues)

Multiple systems beyond the single engine (ex, a system in a wing or tail section not associated with the engine itself)

Obviously some of these are aircraft specific.

More importantly the follow on issue is the corrective action.

[barit1]

From the Canadian Press, 12 June:
Ground rests on the jetliner resumed Tuesday for the first time since the incident, after which the engine in question was shipped to manufacturer Pratt & Whitney in Connecticut for analysis. The Canadian Transportation Safety Board also opened an investigation.

Bombardier (TSX:BBD-B.TO - News) has said it believes the engine failure occurred in the low-pressure turbine of an engine that was "known to have problems."

The manufacturer has been running stationary tests on other systems, including electrical and avionics in the last week and has begun to repair the first test flight airplane, describing the damage as "manageable."

The CSeries won't make an appearance at the Farnborough Air Show in mid-July.

[barit1]

...and has begun to repair the first test flight airplane, describing the damage as "manageable."

As we used to say, "Jack up the nameplate, and install a new airframe". :O