The Comac C919 is a planned family of 158–174 seat
narrow-bodytwin-engine jet airliners to be built by the Commercial Aircraft
Corporation of China (Comac). It will be the largest commercial airliner
designed and built in China since the defunct Shanghai Y-10. Its first flight
is expected to take place in 2016, with first deliveries scheduled for late
2018. Roll-out ceremony was held in Shanghai on 2 November 2015.
Image: kosnews24gr
The C919 forms part of China's long-term goal to break
Airbus and Boeing's duopoly, and is intended to compete against Airbus A320neo,
Boeing 737 MAX, Irkut MC-21, and other next-generation single-aisle airliners.
Development
Comac applied for a type certificate for the aircraft
from the Civil Aviation Authority of China on 28 October 2010. The company
plans to conduct the first flight of the C919 in 2017, with deliveries
beginning in 2018, whereas Marwan Lahoud, Chief Strategy & Marketing
Officer of Airbus Group, assumes a competition outside China around 2020.
The assembly of the
COMAC C919 takes place in Shanghai. – Image: modernairliners
In June 2011 COMAC and Irish low-cost airline Ryanair
signed an agreement to co-operate on the development of the C919 On 24 November
2011, Comac announced the completion of the joint definition phase, marking the
end of the preliminary design phase for the C919. The company said it planned
to cut the first metal for the aircraft in December 2011, with estimated
completion of the detailed design phase in 2012.
C919's advanced aerodynamics were engineered with the
help of the Tianhe-2 supercomputer. With an estimated development cost of $8.3
billion, Comac planned to produce 5–10 planes per year in 2016 and 2017,
subsequently ramping up to 150 C919s. The company intends to manufacture up to
2,300 aircraft of that type.
In 2014 delivery was yet again delayed by technology and
supplier problems, this time to 2018. Comac rolled out its first C919 aircraft
off the assembly line in September 2015 with no engines installed.
On 2 November 2015, Comac rolled out its first C919
aircraft.
China's Comac C919 plane to Be Tested in
2017: Here
Excerpt
The first test flight of China’s Comac C919 plane will
most likely take place in the first quarter of 2017, Chinese media report.
BEIJING (Sputnik) – The test flight could take place as
early as February, although the exact date has not been announced yet, People’s
Daily said on Saturday citing the Commercial Aircraft Corporation of China
(Comac).
China-made C919 to make maiden flight soon: Here
Excerpt
The C919, the first large passenger aircraft designed and
built by China passed the last expert assessment on Tuesday, its manufacturer
announced.
The aircraft was given the go-ahead to begin a series of
high-speed taxiing tests, the last step before its maiden flight. The process
usually takes one to two months.
According to Shanghai-based Commercial Aircraft Corp. of
China (COMAC), 25 experts from Chinese research institutes, civil aviation
administration, and domestic jet makers formed Tuesday's assessment panel. They
reviewed the preparedness of both the aircraft and ground services for the
maiden flight.
C919 makes maiden flight: Here
Excerpt
The Comac C919 narrowbody lifted off from Shanghai Pudong
International airport's fourth runway at 14:00 local time, marking its maiden
sortie seven years into its development.
Onboard aircraft B-001A as it took off on an overcast
Shanghai day are a team of five. In the cockpit are flight test captain Cai
Jun, co-pilot Wuxi and flight observer Qian Jun. In the cabin are two flight
test engineers – Zhang Da Wei and Ma Fei.
The first flight will lasts about 1.5 hours, during which
the CFM International Leap-1C-powered aircraft's landing gear will not be
retracted, Comac's flight test manager You Li Yan told reporters in Shanghai.
The aircraft is expected to reach an altitude of 10,000ft.
China's COMAC says C919 jet completes 2nd
test flight: Here
C919 performed 2nd flight test this morning at Pudong
airport, which lasted 2h 46m. Photos by 金枫. Source: dafeng cao
Excerpt
China’s domestically developed C919 passenger jet
completed its second test flight on Thursday, the jet’s maker said, but there
were questions about its duration and on the near five-month gap between the
two test flights.
The narrow-body aircraft, which will compete with
Boeing’s 737 and the Airbus A320, is a symbol of China’s ambitions to muscle
into a global jet market estimated to be worth $2 trillion over the next 20
years. It first flew on May 5 after numerous delays.
“The plane has made a smooth return,” a spokesman for its
manufacturer, Commercial Aircraft Corp of China (COMAC) [CMAFC.UL], told
Reuters.
Design
Design and assembly of the aircraft is done in Shanghai,
using foreign-made jet engines and avionics. However, China has expressed its
desire to produce a domestically made engine for the C919.
The center wing box, outer wing box, wing panels, flaps
and ailerons are planned to be built in Xi'an, China. The center fuselage
sections are planned to be built in Hongdu, China. The airframe will be made
largely of aluminium alloy. The center wing box was originally intended to use
of carbon fiber composites, but the design was changed to an aluminum design to
reduce program complications.
Center wing box – Image: comac
The center fuselage section – Image: Romain Guillot
CFM International will supply a version of the LEAP
engine, the LEAP-1C, to power the aircraft The engine's nacelle, thrust
reverser and exhaust system will be provided by Nexcelle, with such features as
an advanced inlet configuration, the extensive use of composites and acoustic
treatment and an electrically operated thrust reverser. Michelin will supply
Air X radial tyres.
LEAP-1C
Figure 1. LEAP-1 engine cut through showing the
main areas of interest. Source: CFM.
No 1 marks the fan and fan case.
GE is the world leader in CFRP-based fans (first with GE90) and fan cases
(first with GEnx). LEAP is now taking this technology further. The GE90 and
GEnx blades are hand-laid up from CFRP prepreg cloth. Snecma, which has
responsibility for the fan and low pressure parts in CFM, has formed a joint
venture, Albany Engineered Composites Inc. (AEC, Rochester, N.H.) with one of
US high tech weaving companies, Albany International. AEC has the technology to
weave the Carbon fibers into a 3D mesh which when placed in a form get soaked
in injected resin.
Figure 2. Albany Engineering Composites, AEC,
resin infusion fan blade form with the interlocked weaved carbon fiber in
place. Source: AEC
With this technique, fibers can be woven in an
interlocking manner eliminating any risk of delamination associated with the
discrete layers of prepreg in conventional blade layup. The technique can also
be more automated, necessary for the high volumes that the LEAP will be
produced in.
This process also gives very exact control of the blades
properties like directional stiffness of the different parts and we understand
that Snecma is using this to have the blades form themselves according to their
working condition. A modern fan is a very advanced piece aerodynamically. Its
tips are supersonic, the middle part has transonic aerodynamics and the inner
part has subsonic aero. This requires different aerodynamic forms, from thin
and pointy to blunt and round. In all 3D woven resin infused blade ensures a
very exact blade with high efficiency and low weight. AEC is also producing the
fan case in the same way, first forming the weave and then infusing the resin.
Right after the fan come the booster compressor. As it
sits on the same diameter as the fan’s inner part it has subsonic aerodynamics
and a low speed through the air. The pressure gain is therefore low, on the
level of the fans average pressure ratio of around 1.4-1.5. Conversion
efficiency, shaft hp to pressure gain, can still be as high as the fans
efficiency using today’s advanced 3D aerodynamics, above 90%.
No 2 denotes the variable bleed
ports on the outer part of the swan neck duct between booster and compressor.
The fan will ingest debris like sand from the runway. It is important to keep
that away from the fine dimension of gaps and seals in the core. CFM uses
several techniques to ensure this:
– the spinner form
throws most debris past the core entry, into the bypass.
– The small
particles that do enter the core swan neck will then slide on the outer wall of
the duct due to its curvature where the engine control computer, the FADEC, can
angle the handling bleed doors slightly open to catch the particles that got
ingested and route these to the bypass duct. This technique has been proven on
the GE90 operating in sandy environments.
No3. Snecma is also responsible
for the gearbox with accessories. It is mounted on the fan case to ease service
access and slung to the side to maximize ground clearance.
No 4. The passing point of the
responsibility in the core from Snecma to GE Aviation, where the booster swan
neck leads into the High Pressure Compressor, HPC.
No 5. The high pressure
compressor, HPC. It takes the air from a pressure raise of around 2 and raises
that to above 40 before the air passes into the combustor. GE Aviation is known
in the industry to be the masters of efficient high pressure rate compressors.
Our simulations for cruise suggests the HPC for the MAX8 consumes around 9,500
hp to do that with a conversion efficiency (shaft energy to compressed air
energy) of well above 90%. At its peak operating point it can raise the
pressure 22 times, most of the time it is operating around 20 times however.
One of the effects of this high compression is that the
air gets hot, at ground level and hot take-offs the HPC exit temperature can be
a limiting factor. Our simulations with GasTurb suggest the HPC exit would be
at around 700°C or 1,200°F. The last stages of the HPC is therefore made with
heat resistant nickel based alloys whereas the early stages are made of
Titanium. They can be machined in on piece (nickel based alloys are not easy to
machine), so-called BLISKs, giving both aerodynamic (leakage) as well as
manufacturing advantages.
At this point it can be instructive to understand that
most values in a turbofan engine vary with the demanded thrust. Figure 3 is
showing a diagram from a GasTurb simulation of the LEAP-1B at average cruise
height. It shows what happens with specific fuel consumption (SFC), overall
pressure ratio (OPR) and by-pass ratio (BPR) when the engine goes from en-route
climb (5,300 lbf) to cruise (4,500 lbf) to flight idle (probably around 1,000
lbf).
Figure 3. Simulation of LEAP-1B working line
with GasTurb12. Source: GasTurb and Leeham Co.
The diagram shows several interesting aspects of turbofan
design:
TSFC: this varies with every thrust setting of the
engine, important is that the TSFC “bucket” has its minimum at cruise thrust
(between 4,000-5,000 lbf).
OPR: The overall pressure ratio of an engine is a
function of its rpm, high thrust = high rpm = high OPR. The important area is
once again cruise where OPR would be around 40, a good value and one of the
corner-stones in the high efficiency of the LEAP.
BPR: Finally the By Pass Ratio, BPR, is varying from 8.7
to 13-15 at flight idle. BPR is strongly coupled to how hard the engine is
working, the higher thrust, the more air through the core (to generate shaft
hp) and lower BPR. This is why higher rated members of an engine family always
have lower typical BPR. The kink in the BPR is from the on-set of a handling
bleed through the variable bleed ports after the booster. At low load the HPC
gets to aggressively feed by the booster and therefore excess air is bleed into
the bypass channel from (in our simulation) 2,200 lbf thrust. Should this not be
done the HPC early stages would stall.
No6. On our journey through the
engine the next station is the combustor. One of the problems with high
pressure ratios in turbofans is that this creates high levels of NOx emissions.
GE has developed a lean burn two-zone combustor series called TAPS to master.
LEAP is using the latest incarnation of this technology, TAPS II. The TAPS
combustor also has a very uniform distribution of the heat in the exit gasses
to avoid hot spots in the combustor nozzle and the first high pressure turbine
stage.
No 7. LEAP divides the driving of
the high pressure compressor over two turbine stages instead of one for the
CFM56. This is necessary as the work done in the HPC has doubled, from maximum
pressure ratio 11 for the CFM56 to 22 for LEAP. To create shaft hp efficiently
with the smallest core, the gasses entering the turbines shall be hot and at
high pressure. State-of-the-art right now (GEnx-1B75 ) is 1,700°C or 3,150°F
turbine entry temperature and about 55 in pressure raise from inlet to first
turbine. As stated by CFM, LEAP has another optimization philosophy than GEnx.
We have assumed around 1,550°C and a pressure rise of around 50 at the most
extreme working point.
To withstand such temperatures, the turbine section requires
cooling and quite a lot of it for the first stages. At the toughest operating
point, which we found to be one engine out at V2 on a hot day, the turbines
needs over 20% of the air produced by the compressors for cooling. This cooling
air is consistently taken from the lowest compression level possible in the
engine, from fan, booster, compressors and even combustor; the pressure need to
be high enough to secure positive circulation in the cooling object at all
conditions but not more, any more pressure and the air is hotter than needed
(worse cooling result) and more engine work has been invested in creating the
cooling air than necessary.
A turbofan is therefore riddled with cooling air
off-takes. The CFM56 has about 10, from after the fan for nacelle and aircraft
bleed air cooling to the HPT being cooled with air from the combustors
peripheral airflow. The highest cooling demands are for critical flight cases
like takeoff or one engine flight. For cruise, the demands are lower. It is
therefore attractive to regulate the cooling air for the different load cases.
Easiest is to regulate the air to the stator side but the latest airliner engines
have also regulated the air to the turbine rotors. To check what regulated
turbine cooling would give, we halved the turbine cooling air in our simulator,
which gains the engine about 1% in TSFC.
Better still is to use materials that require very little
cooling such as Ceramic Matrix Composites, CMC.
GE is a leader in the use of CMC for turbine engines. GE has deployed it
in their stationary gas turbines for years and the LEAP now forms the premier
for deployment of CMC in airliner engines. The application is on the outer
shroud of the first high pressure turbine, Figure 4.
Figure 4. First high pressure turbine shroud
which uses CMC lining elements. Source: CFM picture with Leeham Co commentary.
This is a clever choice. Should CFM hit any trouble with
such an application it should not be difficult to replace it with a
conventional Nickel alloy shroud. The drawback would be higher weight and
perhaps more important, an increase of the cooling air flow to the shroud, but
the change of the section to a conventional layout would be pretty straight
forward. We don’t expect this to happen, GE has major knowledge and investments
in CMC technology, but it shows how one approach new technology in a prudent
way.
No 8. The Low Pressure
Turbine, LPT, is the real work area of the engine. This is where the thousands
of horsepower are produced to drive the fan (and the booster compressor but it
only consumes a fraction of the power). At hot day sea level takeoff, the MAX 8
would ask the LPT to furnish the fan+booster with 29,000 hp. It does this work
by dividing the extraction of the power in the gasses over five turbine stages
with flow turning stator guide vanes in-between. It is therefore natural the
LPT is a major building block of a modern turbofan and it constitutes an
important part of the engine weight. The first stages operate in high
temperature (around 1,000°C or 1,800°F) and are implemented in heavier nickel
based rotor technologies but when the temperature sinks the last stages are
made with lighter Titanium-Aluminide alloy technology.
Source: leehamnews
Dimensions of the C919 are very similar to the Airbus
A320, possibly to allow for a common pallet to be used. Its fuselage will be
3.96 metres (13 feet) wide, and 4.166 metres (13 feet, 8 inches) high,
producing a cross-section of 12.915 square metres (139 square feet). The
wingspan will be 33.6 metres (110 feet, 3 inches), or 35.4 metres (116 feet, 3
inches) if winglets are included.
Payload will be 20.4 metric tonnes. Its cruise speed will
be Mach 0.785 and it will have a maximum altitude of 12,100 metres (39,800
feet).
There will be two variants. The standard version will
have a range of 4,075 km (2,200 nmi), with the extended-range version able to
fly 5,555 km (2,999 nmi).
According to a film shown by Comac at the 2010 Zhuhai
Airshow, the company plans to build six different models of the aircraft: a
base passenger aircraft with 168 seats, as well as stretched and shrunk
passenger versions,business jet and freighter models, and a type designated
only as "special".
Target
The Comac C919 is intended to be a new entrant in the
commercial airliner market specifically targeted at low-cost airlines. Fuel
price increases are especially damaging to the low-cost flying model, leading
these airlines to renew their fleets frequently. This ensures optimal fuel
performance and reliability across a single-type fleet. Direct competitor Boeing
737 MAX unit cost of US$80.6–116.6 million in 2015 means that target
price for this airplane should be lower. The Airbus A320neo has a
wider price range of US$75.1–125.7 million. The Comac developers have not
announced a price tag for each plane, although based on industry speculation
current orders for 2012 could be worth more than US$26 billion. With 380
orders secured as of 2012, this results in projected average price of
about US$68 million.
Honeywell Eyes $15 billion Opportunity on
Comac’s C919: Here
Excerpt
Honeywell’s partnership with the Commercial Aircraft
Corporation of China (Comac) C919 program represents a $15 billion
opportunity for the U.S. company, its top regional aerospace official
told AIN in the run-up to the Singapore Airshow.
“It’s going to be a great aircraft. If you read deeper
into the aircraft, it will be very competitive with the aircraft that are
flying right now,” said Briand Greer, president, Honeywell Aerospace Asia
Pacific. “It’s not old, but current, technology.”
Comac’s efforts to develop a domestic aircraft to take on
the market’s dominant narrow-body players, the Boeing 737 and the
Airbus A320, have faced repeated setbacks. Despite delays, the arrival in
November of a prototype represented new progress.
Honeywell joined the project in 2010, when Comac invited
it to provide four essential components, “including flight control systems,
wheels and brakes, auxiliary power units, and navigation systems,” the company
said.
Some experts believe the C919 will not be competitive either technologically or commercially when it enters service given the plane's strong dependence on foreign suppliers. In particular, the engines will likely be sourced from CFM International Inc. (LEAP-1C engine), the same company that sells the CFM International CFM56 used by direct competitors. Others also say that it will most likely not be competitive given that every single commercial airline (except for City Airways which is based in Thailand) that has placed an order for the aircraft is a Chinese airline that wants to support their country's technology. This idea is reinforced because all of the Chinese airlines that have placed orders for the C919 already have either the Boeing 737 or Airbus A320 in its fleet. In 2013, state-owned newspaper Global Times complained that an Aviation Week editorial about the bleak prospects for the aircraft "maliciously disparaged the future outlook for the C919."
Honeywell: Chinese contract agreed: Here
Excerpt
Honeywell has been selected by Commercial Aircraft
Corporation of China, Ltd. (COMAC) to supply its 131-9[C9C] Auxiliary Power
Unit (APU) and associated equipment for the C919 single-aisle commercial
airliner.
The new APU design is based on Honeywell’s highly
successful 131-9 family of APUs, which have more than 51 million hours in
commercial service on narrow-body aircraft like the Boeing 737 and the Airbus
A320.
“Honeywell’s 131-9A is the most popular APU for
single-aisle commercial aircraft in the world today,” said Honeywell Chairman
and CEO Dave Cote. “Our APU has proved to be highly reliable, fuel efficient
and quiet in the millions of hours of in-flight service that it has recorded to
date.”
C919 Supplier Table
COMPONENT
|
SUPPLIER
|
Engines
|
|
Avionics
|
Rockwell Collins, Honeywell,
CETC, GE AVIC, (General Electric joint venture with AVIC (Aviation
Industry Corporation of China))
|
Fight
Control System – Full Authority Fly by wire and advanced active control
technology.
|
Parker,
AVIC, Honeywell, MOOG
|
Landing
Gear System
|
Liebherr
|
Hydraulic
System
|
Parker, AVIC
|
Air Conditioning System
|
Liebherr
|
Electric
System
|
Hamilton, Sundstrand, AVIC
|
Flight Deck and Cabin
Interior
|
FACC, XML
|
APU (auxilary power unit)
|
Honeywell, AVIC
|
Fire protection
|
KIDDE, AVIC
|
Lighting
System
|
Goodrich, AVIC, TM, Jiuzhou,
Eaton
|
C919 Specs
The first iteration of the family of airliners planned by
COMAC is the 156-174 seat C919. This
will be the smallest of the plane makers’ offerings and looks to be offered in
6 variations. It is hard to know if this encompasses the whole fleet of C919,
C929 and C939. The offerings are called:
Baseline, Stretched, Freighter, Shortened, Business and Specials.
The C919 flight deck is very much along the lines of the
Airbus style, with a side control joystick instead of the standard control
column controlling the fly by wire system. Instrumentation is state of the art
with two 15.4 inch main display screens in front of each pilot as well as a
12.5 inch side screen below the window. In addition, the C919 will be offered
with the option of a HUD (Head Up Display). This is used in fighter jets where
instrument data is projected onto a window in front of the pilot so
he can monitor data such as airspeed, altitude
and other information without having to look down. In other
words his/her head remains up.
Material source: modernairliners
Orders: Here
Military application
Specifications
C919-Mixed C919-All ECO C919-High Density Flight crew 2 Seating capacity 156 (2-class) 168 (1-class) 174 (1-class) Seat pitch base line 12 passengers (97 cm (38 in)) + 144 passengers (81 cm (32 in)) 168 passengers (81 cm (32 in)) 174 passengers (76 cm (30 in)) Length 38.9 metres (127 ft 7 in) Wingspan 35.8 metres (117 ft 5 in) Wing area 115 square metres (1,390 square feet) Wing sweepback Height 11.95 metres (39 ft 2 in) Cabin width 3.9 metres (12 ft 10 in) Cabin height 2.25 metres (7 ft 5 in) Aisle width Seat width Typical empty weight Maximum take-off weight 77,300 kilograms (170,400 lb) extended range Range fully loaded 4,075 km (2,200 nmi) 5,555 km (2,999 nmi) Max. operating speed Mach 0.785 900 kilometres (560 mi) (extended range) Normal cruise speed 834 kilometres per hour (518 mph) Take off run atMTOW Service ceiling 12,100 metres (39,700 ft) Powerplants (2x) CFM International LEAP-1C Single turbofan engine Engine thrust 110,000–130,000 N (25,000–30,000 lbf)
| C919-Mixed | C919-All ECO | C919-High Density | |
|---|---|---|---|
| Flight crew | 2 | ||
| Seating capacity | 156 (2-class) | 168 (1-class) | 174 (1-class) |
| Seat pitch base line | 12 passengers (97 cm (38 in)) + 144 passengers (81 cm (32 in)) | 168 passengers (81 cm (32 in)) | 174 passengers (76 cm (30 in)) |
| Length | 38.9 metres (127 ft 7 in) | ||
| Wingspan | 35.8 metres (117 ft 5 in) | ||
| Wing area | 115 square metres (1,390 square feet) | ||
| Wing sweepback | |||
| Height | 11.95 metres (39 ft 2 in) | ||
| Cabin width | 3.9 metres (12 ft 10 in) | ||
| Cabin height | 2.25 metres (7 ft 5 in) | ||
| Aisle width | |||
| Seat width | |||
| Typical empty weight | |||
| Maximum take-off weight | 77,300 kilograms (170,400 lb) extended range | ||
| Range fully loaded | 4,075 km (2,200 nmi) | 5,555 km (2,999 nmi) | |
| Max. operating speed | Mach 0.785 900 kilometres (560 mi) (extended range) | ||
| Normal cruise speed | 834 kilometres per hour (518 mph) | ||
| Take off run atMTOW | |||
| Service ceiling | 12,100 metres (39,700 ft) | ||
| Powerplants (2x) | CFM International LEAP-1C Single turbofan engine | ||
| Engine thrust | 110,000–130,000 N (25,000–30,000 lbf) | ||
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