By Bjorn Fehrm
March 3, 2020, ©. Leeham News: Airbus has started the additional flight testing needed to certify the 251t version of the A330-900. It needs to verify the handling of the aircraft at the higher weight allowed by a 251t MTOW (Maximum Take-Off Weight, up from 242t for today’s A330-900).
The flight test campaign is short, about 40 hours in all. This allows for certification and first deliveries by mid-year. The smaller A330-800 will certify the 251t version next year.
The benefit of nine tonnes higher MTOW is longer range. The A330-900 has large tanks, 139,000 liters, but you can’t fill them with today’s MTOW of 242t.
With the additional nine tonnes of fuel, the A330-900 can fly 7,200nm when flying with Airbus’ rules for passenger weight and mission reserves.
We will look at the range capability of the aircraft with typical airline rules in an article tomorrow where we use our airliner performance model to analyze the practical benefit of the new variant.
The A330-800, the 250 seats shorter version of the A330neo, will get the higher MTOW certification next year. The present 242t version of the A330-800 was certified last month, on the 13th of February.
Airbus could extend the range of the A330neo without an empty weight increase. The higher MTOW required strengthening of a few parts in the wing, fuselage and landing gear, but as these areas changed, some weight savings were realized.
The net effect is the 251t version of the A330neo (-900 and -800) will have the same empty weight as today’s A330-900 and -800.
The changes also had some other benefits. The update of the landing gear allowed an extension of the overhaul cycle from 10 years for today’s version to 12 years, lowering the aircraft’s maintenance cost.
Will the weight increase have any impact on MZFW, like it has on the A330 Enhanced?
A330E has a MZFW of 175t up to TOW 238t
Beyond 238 and up to MTOW 242t you have to subtract 1t from MZFW for every t increase from 238 to 242t. So at TOW 242t the MZFW is 171t.
typo: today’s MTOW is 242t not 245t
According to the airport planning data the 251t MTOW has 177t MZFW. There is or will be a 247t MTOW version with 181t MZFW. There are only these two MZFW weights.
Bjorn,
is there a difference in price and OEW between the 177t and 181t MZFW versions?
Does the 230t MTOW version has the same OEW as other versions?
Thanks in advance
Hi Leon,
the OEW hiked about 5t ceo to neo (bigger and heavier engines and nacelles, wider winglets, the 230t A330 was a ceo), then it has stayed the same for the neos.
Hello Bjorn
I just checked the easa tcds
Max mtow is 242t I guess for both – 900 and – 800
Did I miss something?
Best regards
Thanks, it’s 242t, corrected.
Will TAP and Delta be able to re certify their A330NEO on this MTOW? Delta likes to stuff their A330s..
Not according to FlightGlobal “Airbus says the weight increase and the associated changes to the new variant cannot be retrofitted to earlier aircraft.”
“Airbus has reinforced structures on the higher-weight aircraft but, through a weight-reduction effort, kept the maximum empty weight and zero-fuel weight unchanged.
The 251t version has a modified landing-gear – which also extends the overhaul time from 10 years to 12 – but will not have to undergo a rejected take-off test, says Cottet, because previous testing covered the full range of take-off weights.”
“Airbus says the weight increase and the associated changes to the new variant cannot be retrofitted to earlier aircraft.”
https://www.flightglobal.com/air-transport/airbus-aims-for-short-test-campaign-on-251t-a330-900/137058.article
So short answer, no for existing delivered aircraft, but potentially yes for new aircraft.
Interesting statement “becoming a true transpacific aircraft” – Maria-Luisa Lucas-Ugena
Delta is using a 281 seat configuration on the A330-900 (12 seats less than on the A330-300) and 306 seats for the A350-900.
I would like to see their fuel/range comparison. At which range with the same payload is the A350 better?
Delta will have 37 A330-900 and only 29 A350-900. Seems they love the A330.
The A330-900 without center fuel tank might reach 6000nm, enough for most routes.
This brings me to one of my unloved “pet” aircraft, an hypothetical “A330-1000”. Stretched A339 by 4-4.5m to ~340-500 length (68m), add 2 wheel rear landing bogeys as per A340’s. MTOW of around 255T, 76Klb engines, +40-50 pax in typical layout, 6000Nm range and you have a very useful uncomplicated aircraft that could be produced and sold at relatively low cost.
Not sure what MTOW the A330NEO wing can handle, so that’s a question for Bjorn.
That sounds like it would under cut the market for the A350-900.
To me the MTOW increase sounds like its in response to a specific Airbus marketing campaign for an airline or routes . Some one mentioned ‘true trans pacific plane’. So Im thinking from central Asia/China to the US as it can do northern Asian cities. With the drought on 787 orders from Chinese airlines, Airbus has to make sure its offering can take advantage of that opportunity.
Agree, it could undercut some 359 sales but see its main application in Asia/China/India serving trunk routes in relatively high density layouts. Depending on exit limitations an airline such as Air Asia-X could fit 450 pax? Routes typically varying from 1K-3K Nm’s. LCC’s could find it attractive to fly between India and the UK for example.
On the other hand it could be fitted with a more “luxurious” layout and still carry a decent number of passengers as British Airways is doing with their 787-10’s for Trans-Atlantic flights. For me the A330 remains the most comfortable twin aisle in economy (2-4-2).
If Airbus can get their freighter ducks in a row an A330-1000F can fill the gap between the 767’s and 777″s.
Your pet A330-1000 doesn’t make sense. Adding extra landing gear means a lot more weight (Landing gear are heavy!). Airbus would never add more MLG just to increase the MTOW by 4 tons- almost all if not all of that MTOW increase would get eaten by the OEW increase giving you the same (or worse) performance as a stretch A330-1000 at 251t with the current gear.
If Airbus was to add gear it would be for a significant MTOW boost, and Airbus will never do that to the A330 now because it would compete too much with the A350.
So Airbus re-designed the MLG on the A330neo, made it stronger and at the same time reduced weight.
Did they do that for all aircraft?
Will they do the same for the A321XLR to increase MTOW?
Was this done on the A220 to increase MTOW?
The A350-1000 will increase to 319t, is it the MLG too?
It’s great if Airbus finds ways for improvements and weight reductions and incorporate it on all aircraft. If airlines order Airbus they can assume they will get a better aircraft than specified today.
The A330 has a lot of built in margin due to the A340 since the largely similar A343 has a 276t MTOW. Airbus is cutting weight on the Neo by cutting out that margin and reoptimizing parts for the current MTOW window. Makes the Neo better, but it means the wing and frame are not as well suited for higher MTOWs as before (which is ok because Airbus has the A350 now for that space).
The A330 is rather unique because of the A340. Other planes like the A321 and A350 do not have as much excess structure so cutting weight out of them will be harder.
Adding 5 m to the A330-900 would take approximately 9t (OEW difference between A330-200 and -300).
Coincidently, it would be recouped this latest 9t MTOW bump, spending it not on payload-range but on capacity (30-40 xtra passengers, galley, a lav etc) . Range would take a hit, that might still be very acceptable.
A kind of 787-10 (787-9 & 787-10 same the MTOW). Not sure if it would be a viable business case. The A350-900 probably overall is a better investment.
Fuselage engineering / ground clearance at take-off should’t be too much of a challenge. The A340-500 fuselage is 67.9 m, a good stretch over the A339’s 63.7m and the A346 is way longer..
Typical early adopter disadvantage then, no being able to benefit from early enhancements. Still consequences are probably limitted for Delta’s use, TATL & S. America. And they probably got a suitable price for ordering early.
Delta’s primary use for those aircraft has been TPAC, not TATL. They still have plenty more to onboard, and can bump later deliveries to 251T by simply stroking a cheque, if they so desired.
Would anyone like to compare (range, etc) how this A330neo variant stacks up against 787? I guess that the yet-to-be-published article Bjorn mentioned will do just that…
2017 story
” Airbus is working on increasing the range of the larger variant of the A330neo to 7,000nm. The present version, A330-900, flies 287 passengers 6,550nm, according to Airbus….
But the Airbus 7,000nm is not comparable to the 787-9’s 7,635nm with 290 passengers.
https://leehamnews.com/2017/09/28/airbus-working-7000nm-a330-900neo/ [subscriber only but the indro gives an idea]
The current indro gives a bit more ,7200nm using Airbus rules
Obviously you tune your aircraft to your usage. You also choose the weight variant you need which must be different in price too.
The 251t A330-900 fully fueled with 139090 L (0.8 kg/L) can carry only 27 pax (100 kg/pax), so why even carry the center tank. Without the center tank fully fueled with 97530 L it can carry 359 pax, this makes much more sense. Also how much weight has the center tank you don’t need? This is the performance the 787-9 needs to beat.
The performance you would tune the 787-9 to should be different.
The centre tank is part of the wing box, along with the wing tanks. Sometimes fuselage belly tanks in cargo hold that arent part of the wing structure are added , but not in these planes. As well another location is the rear tail fin.
Not really a thing- ‘ carrying a centre tank’ , you cant leave it behind
The center tank is part of the wing on the A350, but not A330. Even Airbus is showing a paload/range diagram without center tank for the A330.
The A330 has stabilizer tanks too, not the A350.
Leon-
That doesn’t change what he says. Airbus has payload/range charts for the A330 that lack the center tank because not all A330s have it activated. But that just means it is missing some plumbing and sensors, the “tank” is still there it is just empty air. No way to get rid of it.
Thanks Whynot,
Airbus should better write “if activated” instead of “if installed”.
Also why is there no option to deactivate the center tank for the A330-200 and -800 and the 97530 L not mentioned in the describtion like it is for the A330-300 and -900.
Why are the 139090 L not mentioned for the A330-200F.
There needs to be a reason.
Why is there even an option without center tank, for what.
Since Airbus pointed out for the A321 that the RCT has four times the capacity of one ACT but weights only as one ACT, I guess the “old” tanks are little bit heavy.
The centre tank is always present on the A330, it may just be inactive as tanks always have unusable fuel in them and hauling that extra weight isn’t worth the fuel you can tank on top of it with the MTOW.
Best regards
Thomas
Thanks Thomas,
with 300 pax (100kg/pax) the 251t version can only load 105000 L (0.8 kg/L) fuel. With inactive center tank 97530 L fuel can be used. Much better to forget about the center tank in many cases.
Only for other uses than commercial flights 139090 L makes sense. To carry tank weight which is not needed on millions of flights is garbage. I wonder how Airbus thinks about it.
Thomas,
so I checked again, Airbus documents show all A330-200, -800, -300, -900, -200F models with a center fuel tank with (IF INSTALLED).
The technical data for the A330-200 and -800 mention only 139090 L. For the A330-300 and -900 mention both 97530 L and 139090 L. For the A330-200F only 97530L.
IF INSTALLED means that there can be no center fuel tank. Only this makes really sense.
Leon.
what deeper insight are you expecting to achieve with your ever turning ferris wheel of tank or no tank?
your OEW assumption are probably off.
Physical Center tank is presented by the center wing box.
A340-300 wing tanks plus center wing box as tank
A340-200 the same plus one ACT
Initial A330-300 wing tanks only
With the first set of MTOW upgrades:
Introduction of _longer_range_ A330-200 wing tanks plus Center wing box as tank.
( just like the A340-200 was the extended range version of the A340-300: shortened and additional fuel volume available.
After various further MTOW upgrades delta from MZFW to MTOW was large enough to turn the enlarged fuel volume into a viable option for the A330-300 too.
Some numbers are on occasion just that.
All A350 types provide about the same “hollow body” volume in the wings and center wing box assembly. Differentiated volumes for the subtypes is not much more than defining different filling levels. ( Same is valid for 787-8 and -9 actually )
OK, thanks … I get it now.
I saw the payload-range diagram and thought there was something to gain. Sad there is not.
Sorry for bothering you all haha
Leon, it’s probably like the wing box fuel tank of the deHaviland Mosquito, used to strengthen and be part of the wing structure.
“I saw the payload-range diagram and thought there was something to gain.”
A gain would show up as different max payload ( delta caused by tank infrastructure.) and a first corner in payload/range that starts earlier but extends longer before the switch over from MTOW limited to fuel volume limited.
Nicely exposed when you look at some A321 or A320ACJ payload range tables.
“”Nicely exposed when you look at some A321 or A320ACJ payload range tables.””
For the A321neo 5 versions are shown with different ACT and described MTOW.
#1 89t MTOW with 23000kg payload must be the 73.3t MZFW version. OEW must be around 50300kg.
#2 93.5t MTOW with 25000kg payload must be the 75.6t MZFW version. OEW must be around 50600kg.
#3 93.5t MTOW with 1 old ACT with 24390kg payload must be the 75.6t MZFW version. If OEW is around 50600kg same as #2 the old ACT must weight around 610kg.
#4 97t MTOW with 2 new ACT is an ACF with 24000kg payload must be the 75.6t MZFW version.
#5 97t MTOW with 3 new ACT is the LR with ACF with 23560kg payload must be the 75.6t MZFW version. So 1 new ACT for ACF must weight only around 440kg. OEW must be around 50720kg for both #5 and #4.
The A330-900 and 787-9 get very close in specifications after this payload range bump. I did a comparison in 2016 when the range difference was larger.
https://simpleflying.com/wp-content/uploads/2018/12/A339-7879-dimens-keesje_zps1afcfjgm-700×483.jpg
Nice work!
Takes on the A350 and the 787. You gotta love that.
Looks like they should have stuck to their A330 Rev 4 guns despite Hazy and the naysayers.
No. The XWB was the correct way to go
Their product line at the time
A320 6 across seating
A330 8 across
A350 9 across
A380 10 across
The A350 would take on the 777 and the A350neo can counter the 787 in a lot of its routes. The rewinged A330 would have been too expensive for its market
Since that time the 10 across has dropped out and the 5 across been added.
meanwhile Boeing sees an opportunity at 7 across but isnt sure
Well as I recall history, The A350 was the answer then they changed their mind.
Keeping in mind they are down to rte 2 or 3 and Air Asia has pulled their usual kicked the order down the runway………
Also airlines moved over to A350 rather than buy 787, so I don’t think that works logic wise.
Delta had a big contest and the end result was they simply used 787 as a price reducer. Then split their order.
We are seeing 3000 mile sectors for the 787, so all the range stuff does not factor in (Japan is using 787 on much shorter routes)
All you have to do is load less fuel and its a lot more efficient that way.
“”Delta had a big contest and the end result was they simply used 787 as a price reducer. Then split their order.
We are seeing 3000 mile sectors for the 787, so all the range stuff does not factor in (Japan is using 787 on much shorter routes) “”
The cabin without aisles for the 787-9 is 50% bigger than the A321neo, but the OEW is 157% more.
It doesn’t make sense to use the 787-9 in sectors the A321neo can do too.
If airlines are using the 787 on short routes it shows how desperate they are to find a usage.
100,58
Sorry, made a mistake,
The cabin without aisles for the 787-9 is 94% (not 50%) bigger than the A321neo, but the OEW is 157% more.
Contest was between A350/A330NEO and 787 at the time, not A321
IMU the XWB decision came when the FUBAR character of 787 gestation was apparent ( at least inside Airbus ) and a good chance for the regular A330 slogging on quite well ( some MTOW boosts to help ).
I could imagine a little faction fight inside Airbus at the time.
“We will look at the range capability of the aircraft with typical airline rules in an article tomorrow”.
The publication scheduling seems to be off, “tomorrow” was yesterday…. 😉
Best regards
Thomas
“”Airbus has started the additional flight testing needed to certify the 251t version of the A330-900″”
That might be a reason why the payload/range diagram for the neo wasn’t listed in the airport planning data. It might be included soon.
“”The benefit of nine tonnes higher MTOW is longer range. The A330-900 has large tanks, 139,000 liters, but you can’t fill them with today’s MTOW of 242t.””
Fully fueled with 139090 L (0.8 kg/L) the 242t MTOW version has -6272 kg payload. Adding nine tonnes does nothing, payload would reach +2728 kg which is 27 pax (100 kg/pax). For 300 pax the 251t version can only take 105000 L fuel.
The A330-900 makes much more sense without center fuel tank, then it can take 97530 L.
Center tank is integral ( i.e. the center wing box )
difference is a minimal amount of plumbing and sealant afaics.
(Only the A340-200 got extra volume by way of an ACT)
The -200 had it always enabled the -300 got it as option
somewhere around the ~~240t MTOW mark.
Sorry Scott, I’m not a subscriber. Sad not to be able to read Bjorn’s article (and many others) but obviously Bjorn mentioned 7200nm for the A330-900. I don’t know at which payload/pax. So I want to narrow the range possible without center fuel tank, because this makes so much sense.
Airbus describes a 2-class configuration with 310 seats for the A330-900. Virgin Atlantik is using on the A330-300 only 264 seats. I calculate with the middle 287 pax for the 251t A330-900.
With 287 pax (100 kg/pax) 106625 L fuel (0.8 kg/L) can be carried to reach maybe the 7200nm range. A rough linear calculation which can’t be exact is 6585nm range without center fuel tank. That’s more than I expected. The A330-900 is such a great offer.
Even the 242t A330-900 version could carry 269 pax without center fuel tank and should fly even further.
for the A330-200: the MRTT with an MTOW of 233t can fill all its tanks. ( 111t fuel ) i.e. empty weight below 122t.
I’m sure this range bump is a result of specific requests from some ( primarily) existing Asian 330 operators.
The 330neo is never going to beat the 789 on sfc.But aircraft performance is only half ( if that) the story.
If you are a 330 operator the cost of switching your whole hard and soft infrastructure to a new manufacturer/ model is enormous.
Furthermore since the NEO cost $2bn to develop Vs $30bn for the 787 program then it’s clear who can offer the ( much) lower cost of acquisition- ‘list prices’ can be totally ignored.
Since the launch of the NEO I believe Airbus have got about a 30% share against the 787.I imagine that’s probably what Airbus expected.
Since there are no new engines planned at present in this thrust class I imagine this status quo will continue into the future.
“The 330neo is never going to beat the 789 on sfc.”
Questioning that, trying to get the actual numbers would get your posts deleted on some forums 😀
Let’s assume Boeing just did a better job on everything, just because. Despite same engines, CRFP doesn’t help sfc, smaller cross section, better wing AR, 15 yrs of CFD progress and 30 years of continious aero fine tuning on the 330.
Trent11000TEN and Trent7000 being near identical twins has the potential to really give substance to that discussion.
2014 when the neo was launched.
“According to Hamilton, the fuel burn competition between the A330-900neo and the 787-9 will be razor thin, just 1 percent to 2 percent for 4,000 nautical mile segments”
https://www.bizjournals.com/seattle/news/2014/07/21/analyst-boeing-dreamliners-barely-ahead-of-a330neo.html
and for people who love the hard numbers
Analysis of direct operating cost of wide-body passenger aircraft: A parametric study based on Hong Kong- Chinese Journal of Aeronautics
https://www.sciencedirect.com/science/article/pii/S1000936119301244
Unfortunately doesnt have the A330 neo types in detailed results.
A table is supplied with great circle distances, The longest range pair is JFK- HK at 7003 nmi, which is relevant to the discussion about the range boost, but of course the payload boost at a shorter range is useful also.
NY area airports would tend to be payload heavy flights, but Newark doesnt have the runway lengths that JFK has
It would be interesting if the A330NEO had the much better GEN-X engines. Airbus hung their hat on a dog and ……………………
GE has maintained a 2% SFC advantage over the Trents.
We will know in a year or so if RR has managed to fix the Trent issues before they impact the fleet so there is going to be that cost (enough spares to do a voluntary engine swap before a have to engine swap)
Equally so the A330 proves out the 737 as well. A long time in production refined over and over again old aircrat can match up with a newer or new quite well.
Basically there has not been an aerodynamic game changer.
Boeing oddly never applied the 787-9 upgrades to the whole -8 (rear section). Pretty odd as its all supposed to be plug and play and bolt together .
Is CRFP basically a better and lighter materiel but harder to refine how you do your layering and not as long term able to refine when yo figure out you have over built and are carrying excessive weight?
Shades of Mad magazine, spy vs spy vs spy.
Im wondering if there is an airline with A350 orders ‘on hold’, United we are thinking of you, maybe others.
Airbus has looked at their route structure and sees that the range or payload bump means a lot of those planned A350 routes can be met by a cheaper to run plane. This way Airbus gets to keep an order thats in doubt, just shifted to another model.
Well in that case you are incurring the cost of running two totally dissimilar model and those are made from totally different material and process.
Its not like the Ford Mustang and Lincoln/Mercury Cougar where its the same frame, drive-train and with some sheetmetal changes.
And quite puzzling was when the A330 Mk 4 was cancelled, all the airlines that had those on order, moved to the A350. The evidence says they liked Airbus and not Boeing (not arguing that choice) and as long as it was not an A380 they simply adjusted.
So the A330 is really a complete waste of resources when you could be putting them into a once size fits all.
In the end I can only think of Hawaiian as having switched and its not a large fleet.
Airbus is costing itself big bucks and the return is not there as those ops would go Airbus anyway.
The market wanted a 9 abreast plane that had a carbon fuselage as well. Thats why they changed direction with XWB and it worked with 935 orders so far , while the neo gets 300 more for a low cost derivative.
“”So the A330 is really a complete waste of resources when you could be putting them into a once size fits all.””
No.
What was it worth for to make the cabin of the A350 only 0.35m wider. For a narrow 9-abreast in economy class to gain some seats? The A359 is not longer to add another row vs the A339 and all the carbon the A359 is using and the OEW is still 4% more than the A339.
The A350 is a waste. It would have been much better to keep the A330 cabin width. The A330neo is “old” metal, I wonder how much lighter it could be with “new” metal and still be much cheaper than the A350.
“.. the OEW is still 4% more than the A339. ”
For 11% more MTOW and an overall more capable airframe.
The A350 shows the plastics advantage that the 787 more or less only boasts about.
Yes sure, but who really needs more than 7000nm range also at a higher price. Full metall aircraft can still be great.
“”the return is not there as those ops would go Airbus anyway.””
Still great to give airlines an option and us something to talk about.
Boeing does nothing … oh I forgot, they pay dividends.
Argue all you want, all airlines at the time moved from A330X to the A350 and then some moved right back again when the A330NEO was announced.
Of all of them only Hawaiian deserted (no A350-800) and Hawaiian is small potatoes in the airline world (nice jab from Boeing at Airbus though)
So clearly is not size unless it gets into a A350-1000 or 777X.
Now why that is so? Some airlines want Airbus if its remotely close to size and need.
while that is fine and dandy, it also means the A330NEO is a total waste in taking up and costing use of production space , money and resources.
The A330neo project was cheap and I like it more than A350.
For long range I would use the A321 with one stop and change the crew instead of using the A350.
A330 was low cost but all airlines were screaming for high tech so Airbus caved and went A350. then they kept screaming for an A330NEO and Airbus spent more money on it.
That means a production facility, engineering resources, money and people to duplicate two lines that the customers don’t care which they have.
Point is Airbus has both. About rate 10 combined.
Boeing has 787 at rate 10.
I expect all to go down for the next few years. A330NEO more so as Air Asia is kicking a big order down the runway and they are circling the economic drain.
Presumably the neo will replace the standard A330 in production, but attractiveness depends on oil prices which are political with the Chicken Little types like Goon Greta about.
Increase in range of the of the A339 has pushed the A330-800 further into a dark corner as a niche aircraft with very long range and/or when an an airline requires good range from Hot&High airports. So where to with the A330-800?
Airbus void in the 250-275 seat 5000-5500Nm TA market has just become bigger. An 202X version of the A300-600R with effective range of ~5000Nm and OEW of <100T is maybe what is needed in the AB line-up?
An A322 might come as a better 757 successor and that’s it.
As much as I would love a 7-abreast cross section, nobody will do it.
Who wouldn’t want a blended wing body like the Maveric, that’s the future.
I have to laugh at the so called Maveric.
The US has been looking at that for years and suddenly Airbus has discovered it.
See, I said “like the Maveric”,
I don’t care if it’s from Airbus, Embraer or Boeing, if Boeing can build it good. It would provide advantages and other OEM would need to follow.
Only sad that 2-4-2 seat comfort is the past, Maveric has 3-6-3.
Why didn’t the US build it?
xxx-xxxxxx-xxx would be a terrible configuration for passengers. There are 4 seats 2 away from an aisle and 6 “middle seats”.
There are a real issue and perceived.
The seating winds up further from the center if you use the space and you feel more motion due to the length of the arch, much like a record player where the outer edge is the same RPM but is speed is vastly higher.
You need to seat wider to take advantage of the structure.
the other is seeing out which I think no one really cares. Put in flat screens or a viewing technology of some kind and …….
No windows reduce structural penetrations
But its been out there for a long time so its funny to see how wondrous it is since Airbus decided to play with it. More PR.
Much more work done in US on engine placement for the best benefit.
Boeing has made some serious proposal as a freighter to the US government.
I had previously wondered if airbus had taken the wrong approach with the A330neo. Instead of increasing the MTOW, could airbus have lowered the thrust specification like what boeing did with the B777X, consequently lowering the fuel consumption per trip?
Instead of maintaining the same 72klbf of thrust on the A330neo and gaining the MTOW and range, could a 10% lower thrust be sufficient to maintain the same range as the current A330ceo? By doing so the A330neo would have been better optimised for short to medium haul operations below 10hrs leaving the A350 to compete against the B787 in the long haul segment.
It would also make the smaller A330-800 more desirable as a NMA replacement with the derating of the engine from 10% to say 20% which would bring its thrust to below 60klbf and longer cycles between maintenance.
I wonder how would this have worked out?
Derating engines, lowering MTOW to lower costs happens all the time. But it’s a bit like putting a VW 1.6 JTi enigine of 120 shp in Grand Cherokee. It it limitted to 60 mph, can’t tow a boat. And in the end that engine functions better in a leaner car. Because costs are still high for a 120 shp Grand Cherokee.
Yes, and that is because the engines are not operating in its optimal range. Reducing 10% of thrust probably only gain the miserable 1% reduction in fuel consumption. That is very much the limitations of derating an engine.
However when airbus launched the neo, they had the opportunity to rewrite the engine specification. RR would in turn optimise the engine accordingly for lower thrust output, Just like what boeing did with the GE9X. But apparently airbus didn’t not sieze the opportunity and instead copied and paste the engine requirements from the A330ceo to the A330neo, adding an additional clause of 15% lower fuel burn than current A330ceo.
_effective_ downsizing is difficult.
At least more difficult than upsizing.
For upsizing you find the stress points that need incremental beefing up. The rest is already accepting the higher loads. ( until different stress points appear ).
i.e. upsizing is a task with limited scope.
Effective downsizing touches on everything.
The opportunity here is that the neo effectively is a new engine development. So it already encompass all aspects.
airframe != engine.