IAE V2500 vs CFM56-5B on the A320 series
 

Hi
I was wondering if anybody knew the advantages of the two engines when compared to each other. Does one engine have a lower operating cost, fuel flow or more power?!
My FCOMs does not mention anything about this and I dont see anything on the web:8

Thanks

The answer somewhat depends on the version of the V2500 you are operating. I have experience with two variants of the V2500. The V2500-A1 is the older version of the engine, and it has had some problems with compressor blade failures due to something called "rotor bow". If you do some googling, you can probably find more info on the phenomena and on what they tried to do to fix it. The -A1 could also be purchased with a Thrust Bump option, which essentially gives you a thrust boost (approx 10%) for takeoff when the RTOW requires it. This adds significantly to the wear and tear and as a result, these engines fell out of favour with most airlines. The second version I've flown (V2527-A5) is a much better engine with more power and greater reliability but it doe sburn more fuel than it's cousin.

The CFM56 is a very reliable engine. There are over 16,000 of them in operation world wide on various types including all B737-NGs, which is a testament to their durability and longevity. My company has been operating them for 10 years and we just recently had our first engine failure due to an internal problem, the cause of which is yet to be determined. Personally, I would take a CFM engine any day over either version of the V2500.

By market share, CFM is the #1 choice.
 

The CFMs have lower emissions compared to the IAE. Over at the shop, the V2500s ,true to their PW heritage, generally have a lower estimated time to completion for most jobs.

I have heard that one has a better chance of lighting a CFM in cold weather compared to the IAE engine. :}

The big advantage is to Airbus. Airlines use the choice of engines to make GE and IAE compete for the business, and it makes the Airbus more competive vs. the 737, where you have no choice. The Airbus competition gets to the point of giving the engines away.

Boeing are not thinking of competitive advantage, when they offer a choice of engines only on the 757 and widebodies. They would sell more 737 if they offered the IAE as well.

GB

From an operational point of few, here are some differences.

V2500 will go higher, sooner but may struggle the last bit - use V/S, it is better with the Airbus than speed, uses energy better.

Thrust off is different, the V2500 carries residual in the flare - this compounds the autoland differences - the 2 varients have different flap settings in Conf Full and as a result, the V2500 tends to float unless you close the thrustlevers earlier than on a CFM. Much prefer the CFM for autoland - more predictable.

CFM's start quicker - no waiting 50 secs for fuel on a hot start.

Don't forget your ignition on the CFM if weather is bad.

The engineers say the CFM is far more robust, stays on the wing longer but uses more oil - don't worry about regular top offs.

Summary - CFM is better all round :ok:

V2500 A5
 

On our new A321's, plenty of power to altitude! :ok:

A321.....power.....altitude? :confused:
I guess you operate at low TOM's then!!!! :p

CFM has better maintenance costs. Tends to be limited by EGT.

IAE gives better fuel burn (sfc).

In a nutshell.

On the sensible side. We operate the V2500-A1, A5 and the CFM-56. The V2500-A1 has had a few problems such as the stage 4 failure linked to the rotor bow. That has now been sorted after a number of modifications.
The CFM-56 seems to be a very robust engine. I echo the comments above. The V2500-A1 is a slightly more efficient engine (low SFC) and the CFM-56 burns a little more oil/fuel but is more robust/liked by crews (low start times).

DTG

One of those urban legend type things, but by all accounts the CFM will deal with FOD much better than the V2500. I can attest to seeing some pretty bent fan blades on the CFM, and it still getting us home nicely.
Without chucking the same stuff into V2500 in the same scenario, I cant say the CFM fared any better - but it did well.

Apparently less of the "fan growl" from IAE's offering too. Again, unqualified.

Thank you all very much. It's nice to see so many replies. Sounds like everyone tends to like the CFM better:ok:

Yup, the CFMs on the BA bus fleet sound totally different to the IAEs, love hearing a CFM pass by on a bus! Doesn't sound the same on a 737 though...

Yeah, and a Lada sounds different to a Mercedes :p

After years of looking after CFM56-5 powered A320's from Line Maintenance to C check, I am now looking after V2500 powered versions, and as suggested by ASFKAP, we are constantly under the cowls of the V2500 version, new and old with routine maintenance (starter & IDG servicing, ignition, indication and bleed defects), [some of the bleed and indication defects are water/ice related], also the pylons and reversers seem to require more regular attention. Some of the not to old V2500’s (several months) had to be removed rapidly after a manufacturer notified potential compressor problem.
And as suggested earlier the CFM56 seems to be more tolerant to bird/debris ingestions.
For a while some of the new CFM56-5B engines were giving some serious bearing failure problems, but have not heard much lately.
As my V2500 instructor said the CFM56 has a strong controlling FADEC, but the V2500 has weak control.

V2500-a5
 

My outfit has 11 A319-131 using V2500-A5's. We've had them for about 4 yrs and have a despatch reliablity average of 99.8 percent. We also have 20 B737-800 with the CFM option. Their reliability is much the same as ours so there not much in it. The starting time of the V2500 is a bit longer though which can be a bit irritating. This would be helped if Airbus let us start the second eng once the first start valve has closed instead of waiting fir the entire start sequence to finish (about 30sec extra per start)

There aren't many operators who actually made the intentional change from one engine type to the other (as opposed to fleets put together due to a merger), but there are a few. Best known is probably British Airways who operated 10 of the earliest A320s produced (thus CFM of course) for many years, but when they decided to enlarge to a substantial fleet chose IAE instead.

Many of the posts above are by those with practical experience of the types, and I get the feeling that overall you find the CFM better. I wonder what the factors were at boardroom level that led BA to go the opposite way.

Presumably it was in the overall financial package. It must have been a good one to overcome the costs of duplicated spares, training, etc.

My office is some 8 nm west of Heathrow and the fan howl from departing IAE A320 aircraft at maybe 4,000 feet at certain power settings is most noticeable **. To be honest I sometimes ponder how it got through the noise certification as it can be more noticeable than a 747. I have also been seated abeam the front cowl in the window seat, so about 10 feet away from it, on takeoff, and it really is like sitting next to the circular saw in a joinery shop. Fortunately it goes eventually as speed builds.

I have often wondered where the two engines are actually built, because with the volumes coming out it must be a substantial manufacturing operation. Knowing they are both international joint ventures rather conceals it, and their websites say nothing, but I believe the CFMs are built somewhere in France. Is the IAE built in Britain or the US ?