I was reading about the 7E7 today and learned something really cool about it.Say an airline orders 7E7s with Rolls Royce *and* General Electric engines. Now imagine that just before a flight the GE-equipped aircraft has a problem with one of its engines. It has to be removed......there *is* a plane in the hangar - but it has RR engines. No problem. The 7E7 can accept a different engine! Its computer software will make the RR engine behave exactly like the GE engine on the other wing!So yea...the thing can fly with diff engines from diff companies!I thought that was pretty schweeeeeet :)----------------------------------------**Corrected post - thanx michal!**

>Say an airline orders 7E7s with Rolls Royce *and* Pratt &>Whitney engines. Correct, however the choice will be between RR and GE. No P&W for 7E7.Michael J.http://www.reality-xp.com/community/nr/rsc/rxp-higher.jpg

"Correct, however the choice will be between RR and GE. No P&W for 7E7."Yes, but with their -keen- software, they can simulate them...

I thought that this feature was more related to not being sole-sourced on engines. In prior Boeing (and I assume Airbus) aircraft, the a/c is designed to be engine-type specific. That is, you can't change engine type once the a/c is built. This locks a customer into a specific engine type for specific a/c. In the 7E7, I thought that you could change both RR engines for GE, and therefore offer flexibility, but haven't heard of mixing engine types on the same plane.If this is correct, just one more aspect of a real cool a/c!!Bruce.

>haven't heard of mixing engine types on the same plane.Neither have I. Someone I think is getting his imagination run wild !Michael J.

Great idea. If a grounding was ordered for a period,for one type of engine, delays & costs would be reduced.Peter Sydney Australia

I read it also. You can mix engines. It has to do with spares and if only one is available you can use a different engine. I believe it was in the news section of last monyhs Airliner World. Check it out.Andrew

>I read it also. You can mix engines.I wonder where since it is nowhere to be found on the Boeing site and none of the aviation trade magazines (say AW&ST) mentioned it either.Boeing clearly states that engines on 7E7 will be "interchangable" and by this they mean that if airline XYZ that normally uses GE engines buys a used 7E7 from airline ABC that uses RR only then they will be able to swap engines easily. No mention anywhere about being able to fly 7E7 with two different engines hanging from both wings.Michael J.http://www.reality-xp.com/community/nr/rsc/rxp-higher.jpg

I don't want to spoil this, but that's nothing really new.777's can use an intermix of different engines by different manufacturers and of different thrust ratings. Software readjusts itself to the "lowest common denomitator", means, the more powerful engine reduces its output to the "weaker" one.A32x's/330's and 737NG's can use differently RATED engines (same manufacturer though)Seems just reasonable for a brandnew design.Tomey

same here. While it might be possible to replace both engines with a different model I doubt the weight and size differences of having different engines under the wings would be beneficial to flight characteristics :)And that's IF the software allows for different rated engines and compensates the higher rated one to run at less than full power to prevent asymetric thrust.I also doubt Boeing would load 2 engine management programs into the bird, one for each engine.Having one program controlling both requires less computing hardware thus less weight thus making the aircraft more efficient.I also wonder how this affects typerating...Currently aircraft are rated in combination with a specific engine make and model, recertification taking a long time and being expensive.This would have to be abandoned with the 7E7 being certified for any of several engines in any possible combination. I don't see that happening (especially the latter part).

sure, but NOT operationally.Such a config could be used to ferry an airframe home for maintenance or repairs, they're not certified to carry passengers while operating like that.

Neat feature that's for sure, but it's not meant to replace/switch the engine in a short notice as of an engine being out of order and replace in in loco by another one. Changin an engine takes a lot of time (hours), so not so pratical to do, instead thsi feature is intended for a switch of owner regardless of the engine type, you could buy whatever airframe you'ld like an then change the engine type, regardless of the engine assembled in the production line...

Now now...why would I make something like this up!!?? :)Im not a 100% sure of the magazine but Im positive I read it in the latest issue of Airliner World magazine where there are two articles on the A380 & the B7E7.Heres the magazine cover:

>Now now...why would I make something like this up!!?? :)You did not make it up - you misunderstood what you read. As Jeroen correctly stated there is a difference between an operational flight (with paying passengers) and a ferry flight (usually performed by so called "test" pilots). There are many things that are allowed on such a ferry flight (including many non-functional equipment) that are not allowed during normal operations.Michael J.

<<<< You did not make it up - you misunderstood what you read >>>>>Yea I know :) No worries! All in good fun!From what I read in the magazine it sounded like they *are* going to make the aeroplane certified to fly passengers with different engine makes - not just for ferry flights. Im not a 100% sure on that now though!I have to say that I was also unaware that the 777 was capable of accomodating different engines on each wing. So thanks for that interesting info to whoever mentioned that!I wonder what the 7E7's FADEC would think if we bunged a Pratt &Whitney R1830 DC3 engine on the starboard wing mruhahahahaa