COMAC C919

Hendrik_2000

Lieutenant General
Those report of couple months ago about C919 facing delay due to engine problem is not true. Nothing that usual problem that crop up during the test and It has been rectify. Seem the test program is going very well That is why this talk about denying engine license . Via Broadsword
China technical progress has never been easy Her competitor trying all kind of trick to retard or delay her progress because China is such formidable competitor

COMAC C919 Testing Exceeds Cruise Speed, Reaches Ceiling
Bradley Perrett February 11, 2020

Credit: Ministry of Industry and Information Technology (China)

BEIJING—Flight testing of the COMAC C919 has exceeded the designed cruise speed of the narrowbody airliner and reached its intended ceiling, with the fleet of six prototypes now complete.

Elsewhere in the program, COMAC and propulsion partner CFM have modified LEAP 1C engines and nacelles of the six prototypes to cope with previously miscalculated loads, an industry source said.

CFM has further changed the design of transfer gearboxes on the turbofans, the engine company said. According to the source, this modification has been implemented.


The highest speed reached so far has been Mach 0.82, the source said; this compares with the design cruise speed of Mach 0.785. The highest altitude so far has been 39,800 ft. (12,100 m), the source said, the maximum intended for operation. The C919 is designed to carry 158 passengers in a standard two-class configuration.

A second source confirmed that loads on the LEAP 1C engines and nacelles had been unexpected. According to the first source, this resulted in undesirable shuddering. “There was vibration,” that person said. “But the modifications have been made.”


Asked about that issue, a spokesperson for CFM said: “There is no issue with the joint design of the C919 program beyond the normal iteration between the engine manufacturer and the airframer.” Reuters first reported that the issue had arisen. COMAC did not respond to a request for comment on this matter, but the issue does not appear to be unusually serious.

The transfer gearbox has been modified to improve durability, the CFM spokesperson said. The issue was entirely the responsibility of the engine company, said the first source, who added: “All six flight-test aircraft now have the new configuration. So far, there’s been no problem with it.”

CFM said in June 2019 it was redesigning the bearing of the radial drive shaft of the LEAP 1B, the version on the Boeing 737 MAX. This was done after five inflight shutdowns due to particles coming from the shaft, which, with the accessory gearbox and transfer gearboxes, is part of the engine’s accessory drivetrain. The CFM spokesperson declined to say whether the change to the LEAP 1C was related to this or any other product, however. The LEAP 1C is most similar in design to the LEAP 1A of the Airbus A320neo family.

The C919 program is five or six years behind schedule. COMAC said in August 2019 it was aiming at achieving certification in 2021.

The sixth C919 prototype, aircraft 106, flew on Dec. 27, 2019. It will be used mainly for verifying characteristics of the cabin, lighting and exterior noise, COMAC said.

The static strength-test airframe, meanwhile, has undergone all tests necessary for the program’s certification effort. Additionally, the static fatigue-test airframe has been built. The type’s normal flight control law has been verified. COMAC said it, not a supplier, developed this system. Wing de-icing has been tested in a wind tunnel.

Final assembly time for C919s is progressively shortening, COMAC said. The flight-test aircraft are numbered 101-106. Of the static test airframes, the one used for verifying strength is 01, and the one for demonstrating fatigue life is 02. Testing on 01 was completed on Nov. 30, 2019, COMAC said.
 
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Hendrik_2000

Lieutenant General
Via emperor
Development of the domestic alternative needs to be accelerated

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Next-gen Chinese engines power down – but for how long?
By Alfred Chua
22 October 2019

But more than two years later, the fanfare has died down, even as the C919 continues test flights and looks poised to enter service with Chinese carriers – minus the Chinese engines, for the time being.

The prototype of the CJ-1000AX, the alternative powerplant manufactured by Chinese engine maker AVIC Commercial Aircraft Engine (ACAE), was first publicised in December 2017, after 18 months of assembly. ACAE had signed a deal with Comac a year earlier to supply engines to the narrowbody programme.

The CJ-1000AX was touted as the "home-made engine" by the state-owned Global Times newspaper that would "replace imported foreign engines in future". The C919 will initially be powered by CFM International Leap-1C engines.

Last May, the CJ-1000AX hit a milestone in its development when it achieved power-on. The high-bypass turbofan engine's core reached a maximum speed of 6,600rpm, according to Chinese officials.

FlightGlobal has previously reported that China plans to build 24 more CJ-1000 prototype engines to support an airworthiness campaign, with entry into service targeted after 2021.

Citing an Aero Engine Corporation of China (AECC) researcher, Global Times painted a bright future for the turbofan: "The CJ-1000 is designed for the C919, but is expected to power the Boeing 737 or Airbus 320 or a similar newly built aircraft in the world market by 2025."

Meanwhile, the AEF3500 – formerly known as the CJ-2000 – was first unveiled at the 2018 Airshow China in Zhuhai. The turbofan was pitched as a Chinese engine alternative for the Sino-Russian CR929 widebody programme.

Little is known about the status of AEF3500, but media reports suggest it could be put into service on the CR929 by around 2030. Similarly to the C919, the CR929 could enter service in 2025 powered by western engines, before a Chinese-made option is offered a few years later.

It could, however, face competition from Russia in the form of the Aviadvigatel PD-35-1 powerplant. In January last year, United Engine and Aviadvigatel were picked by Moscow to develop the demonstrator powerplant.

While AECC continues with work on the two engine types, the aircraft they were supposed to power are moving on with development. It remains to be seen if China can strike a double win with domestically manufactured engines on a home-grown aircraft.
 

vincent

Grumpy Old Man
Staff member
Moderator - World Affairs
The problem with civilian FBW/FCS isn't so much the technology rather than fulfilling certification requirements in general and for software in particular. Safety standards are higher than military (there is no ejection seat to fall back on as a last resort) but accommodating those on the hardware side with higher redundancy is not rocket science... if you do your homework *cough* 737MAX *cough*. On the other hand, the software not only has to meet requirements, it has to have been developed according to a prescribed process with rigorous documentation requirements. If it wasn't, it automatically isn't admissible - Airbus fell into that trap with the A400M FADEC software, which worked fine but had to be re-written in its entirety because the *development process* did not satisfy civilian requirements.

Getting certification from the FAA is impossible regardless, given the Hegemon’s disgraceful actions recenly. As long as the avionics and flight control software followed the same rigorous standard, there is no reason C919 can’t be a commercial success just by selling to the domestic market.
 

Rettam Stacf

Junior Member
Registered Member
Getting certification from the FAA is impossible regardless, given the Hegemon’s disgraceful actions recenly. As long as the avionics and flight control software followed the same rigorous standard, there is no reason C919 can’t be a commercial success just by selling to the domestic market.

COMAC's current strategy is to get certification in EASA (European Aviation Safety Agency) first. EASA has an agreement with FAA to validate each other's certification process " to expedite issuance of a type certificate without technical review. These changes give both the FAA and EASA the opportunity to have even greater reliance on the regulatory capabilities and the technical competencies of one another’s aircraft certification systems. " (
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). COMAC sees this (relatively) as the path of minimal resistance. And this is one reason why COMAC joint ventures with Russia's UAC for the development of twin aisle C929 (now CR929) because the Russian has experience in working with EASA.

If the US government makes it impossible for C919 to get EASA certification through interference with the process or withholding key US sourced components for the C919, then China will likely just say to hell with international certification and focus the C919, a short to medium haul aircraft, on domestic flights and international fights to neighboring friendly countries. As a couple of forum members already mentioned, the C919 uses a lot of international sub components to make it easier for international certification. China will likely cancel some of these orders and joint ventures to go with her own indigenous sub systems.

As one the world's top 2 commercial aircraft market for the next 20 or more years, every extra C919 sold in China will be a loss to most likely Boeing and US aircraft component manufacturers rather than Airbus.
 
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wilhelm

New Member
Registered Member
In the matter of engines, the PD-14 is in exactly the correct thrust bracket needed for the C919.
It has been flying on the testbed, and as far as I am aware, the first two have been delivered and are being fitted to the MC-21.
The reliance on the US is unwise.. I would be putting feelers out for the PD-14 right now.
 

wilhelm

New Member
Registered Member
The first PD-14 powered MC-21 is due to fly in the next couple of months according to Google..with operations slated for late 2021 early 2022..so pretty much the same timeframe as the 919.
 

manqiangrexue

Brigadier
In the matter of engines, the PD-14 is in exactly the correct thrust bracket needed for the C919.
It has been flying on the testbed, and as far as I am aware, the first two have been delivered and are being fitted to the MC-21.
The reliance on the US is unwise.. I would be putting feelers out for the PD-14 right now.
It doesn't sit right that GE is a 50% partner in the C919. That means this success would be just as American as it is Chinese. I'd rather see some aggressive act by the US government that makes them unable to fulfill their contract, giving COMAC all the justification it needs to eject them from the project with no financial take-away for any of the work they did.

PD-14 is in testing and MC-21 is a direct competitor to the C919 so negotiations won't exactly be smooth as butter but I have no doubt that with the size of the Chinese market as a driving force, the Ruskies will prove to be far better partners. The main issue is making sure that this new engine doesn't turn the C919 into the new 737.
 

Gatekeeper

Brigadier
Registered Member
I won't go as far as callling him the real deal! But I'll say this, he is the real CAPITALIST!

And as such, he recognise stopping engine sales is going to harm USA economic interest in the short and medium term! Not just the engines, but all the other partners associated with the C919 programe. Even though it might not be in the USA long term interest!

But in the words of the great British economists J M Keynes, "in the long run, we all be dead"!
 

manqiangrexue

Brigadier
Yes, yes, the way he put it is funny and as if he has no recollection of what he's been doing for the past year but that's not the point. Other than that I didn't get my wish of seeing GE sabotaged by its own government and expelled from the C919 project, the point is, what happened to Trump? Did he hit is head? Did BoJo curse some sense into him over the phone? It's like his brain is suddenly starting to work and he appears to be capable of learning. Before, he was like some dumb animal you could trick into biting a metal rod with spikes on it every time you moved it around his face but this time, instead he's just looking at you as you waive it! This is literally the first time I've seen him display intellect. I don't like it at all...

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Trump blasts proposed restrictions on selling U.S. jet parts to China
In a series of tweets on Tuesday, Trump said national security should not be used as an "excuse" to make it difficult for foreign countries to buy U.S. products.

"The United States cannot, & will not, become such a difficult place to deal with in terms of foreign countries buying our product, including for the always used National Security excuse, that our companies will be forced to leave in order to remain competitive," Trump wrote on Twitter.

"As an example, I want China to buy our jet engines, the best in the World," he added. Trump later said before departing to California that, "things have been put on my desk that have nothing to do with national security, including chipmakers."
 
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