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Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Columba
Posted 2008-06-26 12:06:43 and read 15065 times.

Browsing to the pictures of the A400M roll out:

http://www.spiegel.de/fotostrecke/0,5538,32835,00.html

I was wondering if a passenger aircraft would be possible using A400M parts (mainly engine and props).
I am not thinking of a A400 for passengers but an aircraft below the A320 series for around 100 passengers using the engine of the A400. Given high fuel prices and the huge success of the Q400 turbo prop engines seem to have a comeback.

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Srbmod
Posted 2008-06-26 12:17:09 and read 15037 times.

Why should they when they have ATR in the fold? The ATR family pretty much makes the need for Airbus to develop a turboprop based off of the A-400M not necessary. ATR has new versions of the ATR-42 and ATR-72 scheduled to enter service in the next few years. Instead of devoting time and money to develop an Airbus turboprop, just use what you already have access to in the ATR family. ATR did have plans for an additional stretch of the ATR design called the ATR-82, but that was shelved back in the mid-90s. ATR could always stretch the ATR design to get it in the 80-90 seat range, and it would more than likely be cheaper than to design and build a clean sheet turboprop.

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Columba
Posted 2008-06-26 12:24:12 and read 15016 times.



Quoting Srbmod (Reply 1):
Why should they when they have ATR in the fold?

I don't know if the A400 engine and prop would fit under the wing of an ATR.
My idea was that the A400 engine was really hard to develop and has cost a fortune and if they could make some more money on the civilian market it would be very much appreciated.

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Srbmod
Posted 2008-06-26 12:43:36 and read 14983 times.



Quoting Columba (Reply 2):

Unless they developed a smaller version of it, you probably won't see it in civilian use The Pratt & Whitney Canada PW100 engine family that is the common engine used on a number of turboprop families has a max hp of 5000 hp, which is less than half of the horsepower of the EuroProp TP-400-D6. Perhaps they could do like P&W Canada did and find some non-aviation applications for the engine (The engine is also used in Bombardier's JetTrain high-speed train concept.). Hopefully the A-400M will have enough success that the EuroProp group recoups their investment.

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Astuteman
Posted 2008-06-26 12:49:42 and read 14975 times.



Quoting Srbmod (Reply 1):
Why should they when they have ATR in the fold?

I suspect there's a subtle difference.....
The ATR's engines are rated around 2 400 shp (ATR72), whilst the A400M's are some 11 000 shp.

A twin-engined Turboprop using these engines could have an MTOW of the order of 150 000 lb (I've assumed 1/2 the MTOW of the A400M), compared to about 50 000 lb for the ATR72

That's a pretty big plane..  Smile

Rgds

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Srbmod
Posted 2008-06-26 13:02:34 and read 14919 times.



Quoting Astuteman (Reply 4):

But you don't need that much power for a turboprop that seats under 100 (Which is what the OP is asking about). That would be like putting a race car engine on a compact car. So unless a smaller variant were to be developed, the EuroProp TP-400 engine will more than likely be a military-only engine unless a civilian cargo version of the A400M is offered.

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Astuteman
Posted 2008-06-26 13:04:11 and read 14919 times.



Quoting Srbmod (Reply 5):
But you don't need that much power for a turboprop that seats under 100 (Which is what the OP is asking about). That would be like putting a race car engine on a compact car. So unless a smaller variant were to be developed, the EuroProp TP-400 engine will more than likely be a military-only engine unless a civilian cargo version of the A400M is offered.

How about a 200 seater... ?  bigthumbsup 

Rgds

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: GST
Posted 2008-06-26 13:17:09 and read 14833 times.



Quoting Astuteman (Reply 6):
How about a 200 seater... ?

A 200 seater turboprop? Now that I'd love to see...we can only hope that perhaps a market will open for one.

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Beaucaire
Posted 2008-06-26 13:20:01 and read 14818 times.

I think the question is justified in that those engines could be used in a 150 seater Turboprop .
The EADS site about the A400M specifically states :

"...The A400M is designed to civil certification standards complemented where appropriate by specific military requirements. The aircraft design incorporates leading state-of-the-art technology including:

*
Fly-by-wire Flight Control System with sidestick controllers
*
Flight envelope protection system, already proven in Airbus commercial aircraft
*
Advanced structural design incorporating extensive use of composite materials
*
High performance turboprop engines, allowing operation in civil air traffic control environment
*
High flotation landing gear, allowing operation from short, unpaved airfields...."

While the A400M is primarily geared to find MIL applications and users,it would be not too far fetched to consider a civil variant ,considering oil at 150$...
75 % of all European/Asian flights are less than 2000 nm- so not a market that could not be adressed by a 350 Mph 150 seater offering 30% lower seatmile costs than a A320 .

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Scipio
Posted 2008-06-26 13:29:35 and read 14765 times.



Quoting Beaucaire (Reply 8):
offering 30% lower seatmile costs than a A320

30% lower seatmile costs, or 30% lower fuel costs? The two are not the same. I presume that time-related costs (staff, capital, ...) would eat substantially into the fuel savings.

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Kappel
Posted 2008-06-26 13:58:02 and read 14646 times.



Quoting Scipio (Reply 9):
I presume that time-related costs (staff, capital, ...) would eat substantially into the fuel savings.

Assuming this aircraft would be able to reach speeds comparable to the Q400, that would not be such a big problem for many routes. But agreed, it would be much less suitable for US transcon, and as such, Western Europe to US East coast ops.

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: KennyK
Posted 2008-06-26 14:33:18 and read 14536 times.

It's getting to the stage now where an 8-bladed turboprop is getting to look like an unducted fan!! Now where is the difference other than their ancestry? And wouldn't an A320 or better still an A340 look cool with a brace or two of those props under their wings!!!

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Keesje
Posted 2008-06-26 14:55:18 and read 14493 times.

Maybe. I determined 2 x 11.000 hp could power ~170 seats single class within a range of about 1500nm.

http://i191.photobucket.com/albums/z160/keesje_pics/turbolinermai17.jpg?t=1214511696
click to enlarge

Result of a long discussions with prop pilots on pprune. I took the TP400 as starting point & determined the MTOW for a twin TP400 aircraft. BAE146 fuselage (minimum 6 abreast) concept, ERJ190 style wing, DLC, it even had APU powered electric drives for taxiing and push backs.

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: Group51
Posted 2008-06-26 15:42:05 and read 14337 times.

Keesje, you are amazing. I love that plane! I hope EasyJet is watching.

Topic: Could Airbus Develop A Pax Turboprop Based On the A400M?
Username: MEA-707
Posted 2008-06-26 16:01:22 and read 14287 times.

With the props seeing a come back, it's indeed weird since the 1960s no turboprops have been built with a wider then 4 abreast fuselage. Probably the last were the Il-18, Electra and Vanguard. Basically being 4 abreast limits the design of the current propliners to around 90 passengers at the max. I think an 5- or 6-abreast turboprop airliner with 130 seats will have a good chance currently, if it can fly around 700 km/hr.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: DavidByrne
Posted 2008-06-26 17:29:51 and read 14181 times.

Surely there's a potentially huge market for a 150-seat turboprop for short sectors (less than 500 miles/800 km) if signficiant fuel savings can be demonstrated over the 737 and A320 series. Over these kinds of stage lengths, the slower speed of the turboprop will mean little time difference, especially if the speeds of the Q400 can be achieved economically. I'm genuinely surprised that there isn't a large civilian turboprop already on the drawing board.

Remember the Tu-114 . . . ? Now that was a large, fast and long-range TP . . . though probably quite uneconomic by western standards. But let's not allow our view of TPs to be confined to 70-90 sets, when 50 years ago a 220-seat TP was in service. And then there was the Vanguard as well - that was surely in the 130-seat bracket, no?

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Aircellist
Posted 2008-06-26 21:47:13 and read 13972 times.

The Vanguard V.953 was pegged at 139 seats, 5-abreast, with 4xRR Tyne MkII engines 5050 shp.

source: Airlines and airliners #3, 1994

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Group51
Posted 2008-06-27 00:24:45 and read 13779 times.

Video on the BBC now of the unveiling:

http://news.bbc.co.uk/1/hi/business/7475687.stm

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Jdevora
Posted 2008-06-27 01:05:29 and read 13695 times.



Quoting Columba (Reply 2):
My idea was that the A400 engine was really hard to develop and has cost a fortune and if they could make some more money on the civilian market it would be very much appreciated.

My understanding is that the A400 development is fully paid by the " seven European launch nations" plus a pre-agreed % as profit. Airbus will "make money" with the follow up orders of an already paid project.

Cheers
JD

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Keesje
Posted 2008-06-27 03:17:05 and read 13527 times.



I checked, the guys are no hobbits, around 1.75 meters  Wink

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Parapente
Posted 2008-06-27 04:19:21 and read 13411 times.

It seems very hard to relate turbo prop power to Jet power but from waht one reads here on this thread these engines (11,000 shp)- in a modern frame would be very capable of driving a 150 seater aircraft and possibly more. As such in this form the plane would sit firmly in the 737/320 replacemnt market. At present there appears to be 3 engine camps. 1, The Cfm camp whose programme envisages creating fuel savings through a series of major updates to a conventional design. 2. P&W who suggest that the only way forward is the geared fan which also releases the core to spin at optimum speeds (12-15% efficiency gain ). 3. Rolls who say "Open Rotor" is the only long term route as it offers about 25% greater efficiencies (something P&W does not disagree with but points out the huge unresolved issue of shockwave blade noise ).

I guess (since we are discussing it) the question is are we /should they -be looking at a fourth route? That of the "supermodern ,triple shafted , blisk using, high pressure/temperature, scimitar (carbon) bladed,geared, turboprop? It must be the utlimate "fuel miser",if for no better reason than the fact that it will (force majeur) fly a little slower.
This is surely the (only) point. If consumers can accept that journey times for the 1-2.5 hour flights are increased by (what?) 15% then surely there is no technology existing or planned that would/could beat such a combination.

That then leaves us with one (big) question.And one I am not going to go into! It is -Has "Peak Oil" arrived or not? If it has "you aint seen nothing yet". $200 will not be far away. You only have to read todays papers about BA restructuring to see how hard the fuel prices are hurting, and climate change has not and will not dissapear -as much as some would love it to.

If this IS the senario then the thread starter has a very valid point indeed. This engine could and should be considered as a very real candidate for the A320/737 replacement and NOW!

Consumers (whose wallets are empty at present) will ,I believe, trade a little time for lower prices (less expensive prices I should say).

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Scouseflyer
Posted 2008-06-27 04:26:29 and read 13380 times.

I don't know about the US but in the UK there is an issue with the public believing that props are "old-fashioned" and even dangerous - this may be an issue that has to be overcome but if U2 ordered 100 of this Turbo Liner this may change pretty quickly.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Keesje
Posted 2008-06-27 04:37:49 and read 13351 times.



Quoting Parapente (Reply 20):
At present there appears to be 3 engine camps.

It seems GE also is working on something. First metal is cut on General Electric's 7,500shp GE38-1B, selected 18 months ago to power the new CH-53K transport helicopter. Honeywell is also working on a > 5000hp engine.

"GE made an investment in this programme as well. It's not just government money," Birtwell says. "We did it for a reason. We are highly aware of the various other applications in this power class."

http://www.flightglobal.com/articles...-future-in-emerging-heavylift.html

http://www.flightglobal.com/blogs/the-dewline/GE38.jpg

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Ty134A
Posted 2008-06-27 05:07:38 and read 13281 times.



Quoting DavidByrne (Reply 15):
Remember the Tu-114 . . . ? Now that was a large, fast and long-range TP . . . though probably quite uneconomic by western standards. But let's not allow our view of TPs to be confined to 70-90 sets, when 50 years ago a 220-seat TP was in service. And then there was the Vanguard as well - that was surely in the 130-seat bracket, no?

Now I can not come up with exact numbers, but I more or less often read that the fuel burn of the TU-114 was very good, and I think of remembering this "very good" in comparison to todays products available. The counter rotating props bring great benefits, again not being able to provide a source I would ask for any further information, maybe on the fuel burn of the engine (which is also mounted on the Tu-95, Tu-116, An-22, as well as on the A-90 Ekranoplan). I believe though that they were (are) pretty noisy, even for former SU standards.

Any backup data welcome...

As to a pax A400,... would it not be a bit to heavy, only looking at the gear, and what about a pressurazation, is it totally pressurized?

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Parapente
Posted 2008-06-27 05:17:17 and read 13245 times.

Don't wish to over state it but of today.... or raise another of todays threads covering TAP (alitalia etc etc) just off the BBC website


"The price of crude oil has surged to a record, breaking through $142 a barrel, amid concerns about the ability of producer nations to meet demand."

"In London, Brent crude jumped to $142.13 a barrel, while New York light crude climbed as high as $142.26. "

Taking into account Keesje's post.It suggests that there are now 3 brand new technology prop engines spanning 5,000 -7,5000 -10,000 shp. This (from this thread) suggests modern twin aircraft of 75,100/115 and 150 plus pax

Yes scouseflyer.Props WERE considered old fasioned -but that was in the 60's!

Today we are in the post Concorde, environmentally friendly,carbon concerned era.You may have noticed Gordon Browns committment to putting up some 4,000 -7,000 wind turbines yesterday. PROPS my friend are about as "In" as you can get right now!

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Parapente
Posted 2008-06-27 05:35:09 and read 13192 times.

BTW. Keesje,whist I do not wish to play engine games....How about this "little" baby?

The Progress D-27 is a propfan engine that the Ivchenko Progress company developed in the 1980s for commercial and military transport aircraft. Unlike the General Electric GE-36 UDF propfan, the D-27 has a fairly conventional layout, with a reduction gearbox linking the power turbine to the contra-rotating propfan blades,at 14,000shp each! Now one is talking a potental 175-200 seater aircraft.

What if the Russians built that? If oils stays where it is (or higher) who could refuse it? It would be as the Americans like to say -a game changer.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Keesje
Posted 2008-06-27 07:17:30 and read 13577 times.



Quoting Parapente (Reply 25):
How about this "little" baby?

I think the russian engineers have a track record in the area of big turbo shafts and the gearboxes that come with it. They made a very lean one that could handle 14.000 and two counter rotating heavy props 50 years ago..

As you mention they have not been sitting on their hands since then, however where financially constrained for a long period. I understand the D-27 is a good engine but their weren't the big orders and budgets to engineer child deceases out of it. I think the russian airforce is showing renewed interest in the Oekrainian Antonov aircraft.

"New" development is something inbetween: NK-93 "ducted propfan"

http://www.flankers-site.co.uk/moscow_2007_files/day03_004.jpg

Obviously trying to combine high bypass ratio with low noise and reduced blade containment risks..

http://www.flankers-site.co.uk/moscow_2007_files/day03_056.jpg

The russian have been working on this engine since the early nineties. radical budget cuts killed progress.. maybe know when russia is rich again..

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Pliersinsight
Posted 2008-06-27 10:04:08 and read 12692 times.



Quoting Keesje (Reply 19):
I checked, the guys are no hobbits, around 1.75 meters

You'd think they would have put the props up about another 6 to 8 inches higher for safety sake as they are just at the height for nasty fatal injury to some ground crew who might be momentarily inattentive.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: R2rho
Posted 2008-06-27 11:46:14 and read 11924 times.

Well, I definitely agree that there is a market for a 100-150 seat turboprop. But that this plane could be based on the A400M.... not so sure. Definitely not on the fuselage, which is build for military cargo. As for the engines, indeed two would suffice to power such a plane. But they are very heavy, have a huge torque, which means lots of wing reinforcement (even the C-130 wing had to be reinforced for one of them) plus engine-out considerations, the aerodynamic effects of the huge prop... it's too much engine for a passenger aircraft I think. The Russians solved many of the above issues by going counterrrotating.....

But the idea is good. The A400M will cruise at Mach .70 and 30000ft - what difference is there to your average flight on an A320? It's definitely worth exploring that path, a shame that A&B are completely ignoring it.

Quoting Parapente (Reply 25):
What if the Russians built that? If oils stays where it is (or higher) who could refuse it?

If Western companies keep hesitating to build a large turboprop for much longer, maybe they will. They have the know how, specially in counterrotating designs, Russian engineers kick ass, alas they lack the money (for now...).

Quoting Keesje (Reply 26):
They made a very lean one that could handle 14.000 and two counter rotating heavy props 50 years ago..

...while having an impressive intercontinental range and cruising at near-jet speeds. Imagine what could be done today if the same effort was put into a new design.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Aircellist
Posted 2008-06-27 16:40:54 and read 11511 times.

In fact, from the few informations available on Wikipedia (so, subject to comments...), the Tu-114 and A400M have engines of equivalent ratings, should cruise at similar speeds (420Kt for the A400M, 415Kt for the Tu-114, which are quite close to the CSeries projected cruising speed of 447Kt as shown in the pdf published by the Runway girl today at http://www.flightglobal.com/blogs/ru...bombardiers-new-cseries-specs.html ).

Now, with the progress in aerodynamics since the Tu-114's era, how would a contrarotating scimitar-bladed prop fare today, speedwise (if there is to be any difference) ?

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Tdscanuck
Posted 2008-06-27 19:43:36 and read 11376 times.



Quoting Jdevora (Reply 18):
My understanding is that the A400 development is fully paid by the " seven European launch nations" plus a pre-agreed % as profit. Airbus will "make money" with the follow up orders of an already paid project.

I believe the A400M is on a fixed-price contract once the development costs are absorbed...so they need to get the per unit cost below the agreed price or they're going to loose money on each frame.

Quoting Pliersinsight (Reply 27):
You'd think they would have put the props up about another 6 to 8 inches higher for safety sake as they are just at the height for nasty fatal injury to some ground crew who might be momentarily inattentive.

I agree that going safer is always better but, like a jet engine, you really have no business being that close to a running propeller.

Tom.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On
Username: PITIngres
Posted 2008-06-27 19:50:46 and read 11361 times.



Quoting R2rho (Reply 28):
... Russian engineers kick ass...

 checkmark 

They certainly manage to disregard conventional wisdom and get away with it. Contemplate an oxidizer-rich turbopump (RD-170), and tremble...

I dunno if the west is ready for an A400M-sized pax t-prop yet, it might be a few years ahead of its time. I am quite sure that I personally will take several hundred km doing Mach 0.70 in a t-prop before doing the same distance in a car at 120 km/hr -- if only the security fascists would get out of my way ...

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Keesje
Posted 2008-07-06 15:52:06 and read 10831 times.

Was RR watching?


Rolls-Royce promotes turboprop solution for new civil airliners

Rolls-Royce is talking up the possibility of a new generation of turboprop-powered aircraft replacing a substantial proportion of today's narrowbody jets.

The manufacturer believes high oil prices are likely to drive airframers to sacrifice cruise speed for economics.

"The TP400 engine [for the Airbus A400M military transport] is a very efficient propulsion system," R-R director engineering and technology, Colin Smith, says. "There is a very sound argument to be made for the majority of the 150-seat market, which flies mostly for less than 1.5h [being turboprop-powered]...if somebody does want a high-efficiency turboprop then have we got one for you."

R-R civil aerospace president Mark King adds: "More and more manufacturers are looking at whether the bottom half of this market would be better addressed with turboprops."

King stresses that the engine-makers have yet to be asked by the airframers to satisfy a specific requirement: "All we know is that a lot of people who currently fly around in 150-seat aircraft will need transporting in the future. Is that going to be in a single-aisle or twin-aisle? There are plenty of persuasive arguments about what that will be.

"What is the range of this thing? A thousand miles [1,600km] or 3,000 miles leads to fundamentally different machines."


http://www.flightglobal.com/articles...boprop-solution-for-new-civil.html

 Wow!  bigthumbsup 

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Viscount724
Posted 2008-07-06 16:16:44 and read 10772 times.



Quoting Aircellist (Reply 16):
The Vanguard V.953 was pegged at 139 seats, 5-abreast, with 4xRR Tyne MkII engines 5050 shp.

That should read 6-abreast. I believe the maximum certificated seating on the Vanguard was 139 but that was only possible with 6-abreast seating. BEA had 6-abreast Y class on their Vanguards. Most were all Ywith 135 seats but they also had a few with 18 first class (2-2) and 109 3-3 Y class.

AC (still TCA when they took delivery of their Vanguards), the only other original customer, had much more spacious 5-abreast Y class seating. If memory correct their final Vanguard layout was 18 F and 90 Y for a total of 108, although when first delivered they had more first class seats, about half the cabin.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: EA772LR
Posted 2008-07-07 09:11:21 and read 10360 times.



Quoting Astuteman (Reply 4):
A twin-engined Turboprop using these engines could have an MTOW of the order of 150 000 lb (I've assumed 1/2 the MTOW of the A400M), compared to about 50 000 lb for the ATR72



Quoting Astuteman (Reply 6):
How about a 200 seater... ?

I think you could be on to something my friend.... scratchchin  A twin engined Europrop powered airplane could theoretically seat 200 pax with a range of up to 800 to 1000nm could be a suitable option, particularly in Europe where many major destinations are within 1000nm of each other. Just a thought

Topic: RE: Could Airbus Develop A Pax Turboprop Based On
Username: Aircellist
Posted 2008-07-07 18:53:12 and read 10119 times.



Quoting Viscount724 (Reply 33):

Quoting Aircellist (Reply 16):
The Vanguard V.953 was pegged at 139 seats, 5-abreast, with 4xRR Tyne MkII engines 5050 shp.

That should read 6-abreast. I believe the maximum certificated seating on the Vanguard was 139 but that was only possible with 6-abreast seating. BEA had 6-abreast Y class on their Vanguards. Most were all Ywith 135 seats but they also had a few with 18 first class (2-2) and 109 3-3 Y class.

AC (still TCA when they took delivery of their Vanguards), the only other original customer, had much more spacious 5-abreast Y class seating. If memory correct their final Vanguard layout was 18 F and 90 Y for a total of 108, although when first delivered they had more first class seats, about half the cabin.

Oh, you are absolutely right. The seating plan at the end of the book is AC's one... Sorry, and thanks!

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Keesje
Posted 2008-07-08 04:29:57 and read 9943 times.



Quoting EA772LR (Reply 34):
Quoting Astuteman (Reply 4):
A twin-engined Turboprop using these engines could have an MTOW of the order of 150 000 lb (I've assumed 1/2 the MTOW of the A400M), compared to about 50 000 lb for the ATR72


Quoting Astuteman (Reply 6):
How about a 200 seater... ?

I think you could be on to something my friend.... A twin engined Europrop powered airplane could theoretically seat 200 pax with a range of up to 800 to 1000nm could be a suitable option, particularly in Europe where many major destinations are within 1000nm of each other. Just a thought

Astuteman, EA772LR I think half weight would not be possible. An A400M having an engine failure at V1 will have 75% thrust left to pull that MTOW aircraft over that obstacle down the flight path. A twin engined aircraft under the same conditions only 50%

If 3xA hp (one engine failure) is needed for quad with a MTOW of B lbs, a twin powered aircraft having 1xA hp (one engine failure) available would have a MTOW of ~0.33 B lbs.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: EA772LR
Posted 2008-07-08 08:58:38 and read 9722 times.



Quoting Keesje (Reply 36):
Astuteman, EA772LR I think half weight would not be possible. An A400M having an engine failure at V1 will have 75% thrust left to pull that MTOW aircraft over that obstacle down the flight path. A twin engined aircraft under the same conditions only 50%

This is true. How about around 125,000lb takeoff weight and a slightly scaled back twin 10,000shp Europrop 200 seat regional aircraft???

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: TylerDurden
Posted 2008-07-08 09:16:59 and read 9689 times.



Quoting EA772LR (Reply 34):
A twin engined Europrop powered airplane could theoretically seat 200 pax with a range of up to 800 to 1000nm could be a suitable option

I doubt any airline would buy it. Airlines do not want an aircraft of that size to be so range limited. Limits flexibility, limits resale...so limits value....
Any aircraft program likely would need to sell 400-600 aircraft to turn a dime....I just don't see that market with a range so limited.

Just my .02.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Prebennorholm
Posted 2008-07-08 10:22:09 and read 9631 times.

I am afraid that we are generally asking too much from the TP400 power system when talking about real 320 / 737 replacements. The reason is that the TP400 system is designed for military specs.

For civil use I would assume those those very high speed propellers to be externally very noisy and not conforming to present day civil noise standards.

But limited to 7,000 or 8,000 HP with a 10% reduction in propeller rotation speed and a propeller which is optimized for low noise, what could it do?

What about a twin version of a modernized BAe-146/ARJ - the long version with 115 seats? Or something similar?

One thing which could discourage such a plane would be the inability of propeller planes to easily climb to high altitudes. A good climb rate on a fast turboprop plane in the thin an cold air at high altitude would require increased propeller rotation speed with tip speed well into supersonic. There goes much of the fuel efficiency gain, and it would noise wise be unbearable to sit on the plane, like it was said to be on the Tu-114.

If such planes are produced in great numbers with ceiling well below FL300, then terrible congestions would be the result at many places in Europe and North America.

There is no easy straigh forward replacement for the modern turbofan engine.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: TylerDurden
Posted 2008-07-08 10:37:05 and read 9604 times.



Quoting Prebennorholm (Reply 39):
But limited to 7,000 or 8,000 HP with a 10% reduction in propeller rotation speed and a propeller which is optimized for low noise,

At what price will we/can we relax noise regulations in the name of economics?
Will this ever happen. Seems somewhat silly that we expect mass transportation to make no more noise than a vacuum cleaner...

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Prebennorholm
Posted 2008-07-08 10:58:44 and read 9562 times.



Quoting TylerDurden (Reply 40):
At what price will we/can we relax noise regulations in the name of economics?

It's not a question about price or costs, it's about politics.

It's a no starter to propose a new airliner which does not comply with ICAO Stage 3 noise rules, and I expect that to be far from the case with the military A400M.

Every major civil airport is surrounded by a few hundred thousand NIMBYs who elect and re-elect local politicians. They will not tell their politicians: "We will gladly accept double noise if that saves $25 for each passenger on his fuel bill on a 1,500 miles flight".

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: BlackProjects
Posted 2008-07-08 11:23:37 and read 9534 times.

Ooooh a GIANT ATR what ever next!  old 

The Russians didnt try it and they have the most powerfull turbo props on the planet 15,000 shp which is why the AN-22 goes so fast and makes so much noise that and the contra rotating props.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: TylerDurden
Posted 2008-07-08 11:49:36 and read 9492 times.



Quoting Prebennorholm (Reply 41):
It's not a question about price or costs, it's about politics.

I hear ya. I was a rhetorical question primarily since noise standards seem to be almost random--at best (the threshold at which they are set).

I just have to wonder that if we can reduce the cost of transportation by 20% at the increase of noise pollution by 5% is that considered a success?

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Keesje
Posted 2008-07-08 13:58:26 and read 9372 times.



Quoting Prebennorholm (Reply 41):
It's a no starter to propose a new airliner which does not comply with ICAO Stage 3 noise rules, and I expect that to be far from the case with the military A400M.

http://www.airbusmilitary.com/images/1strollout02.jpg

Airbus militairy says the A400M meets future noise and emissions regulations. The props are designed to ru at lower RPM avoiding the usual prop tip effects. The noise is supposed to be lower then other props. Listen for yourself (after GPU is switched off  Wink )



From the specs; overall pressure ratio, combuster, materials, SFC (0.41?) this seems a pretty efficient engine regardless of its use.

Topic: RE: Could Airbus Develop A Pax Turboprop Based On The A400M?
Username: Prebennorholm
Posted 2008-07-08 15:44:59 and read 9294 times.



Quoting Keesje (Reply 44):
Airbus militairy says the A400M meets future noise and emissions regulations.

Thanks Keesje, that is very interesting, I didn't know that. I was pretty sure that for a pure military plane like the A400M not one single dime or performance decimal digit would be spent on noise reduction.

That makes a twin TP400 plane as 320 / 737 substitute a more viable project. Still I am sceptical about climb performance at high altitude.


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