Critical engine with counter-rotating propellers

[emilh1]

As far as I know the two outboard engines would be the most critical because of its position in relation to the center line of the fusulage.

Found an interesting link on a new plane called A400M where they have made something called DBE. Two counter-rotating props on each wing.
Check it out!

http://www.a400m-countdown.com/index.php?v=2&spage=7

 

[jbizon]

a twin-engine airplane with counter-rotating propellers has two critical engines

If when sitting in the cockpit your LEFT blade spins COUNTER CLOCKWISE and RIGHT blade spins CLOCKWISE. you have 2 critical engines.

If they both spin toward the fuselage. (LEFT blade spins CLOCKWISE, RIGHT blade COUNTER CLOCKWISE) you have NO critical engine.

 

[MikeD]

If when sitting in the cockpit your LEFT blade spins COUNTER CLOCKWISE and RIGHT blade spins CLOCKWISE. you have 2 critical engines.

If they both spin toward the fuselage. (LEFT blade spins CLOCKWISE, RIGHT blade COUNTER CLOCKWISE) you have NO critical engine.[b/]

Or, they could be both critical....depending on how you look at it, since each still has it's own moment arm to counteract when the other is inop. Same with two outward rotating props, just worse with the longer arm.

 

[tgrayson]

Or, they could be both critical....depending on how you look at it, since each still has it's own moment arm to counteract when the other is inop. Same with two outward rotating props, just worse with the longer arm.

Which highlights how meaningless it is to call them both critical:

Question: Who is taller, Jim or Bob?
Answer: They're both the same height.
Question: Ah, so they're both taller?​

 

[MikeD]

Which highlights how meaningless it is to call them both critical:

Question: Who is taller, Jim or Bob?
Answer: They're both the same height.
Question: Ah, so they're both taller?​

Its potato, po-ta-to there chief. Both critical or neither critical. You'll still have your work cut out for you when one decides to go bye-bye.

 

[z987k]

Its potato, po-ta-to there chief. Both critical or neither critical. You'll still have your work cut out for you when one decides to go bye-bye.

Well you need to be able to define it so you can chose which one fails, duh!

 

[Autothrust Blue]

Well you need to be able to define it so you can chose which one fails, duh!

I still like calling the whole airplane critical!

 

[FullDeflection]

If a mod could change the title to read "Critical engine with contra-rotating propellers" that would be dandy