Second mover advantage? Learnt from China Eastern?
COMAC C919
- Thread starter Deino
- Start date
Second mover advantage? Learnt from China Eastern?
Don't know what you mean by the weight difference and quick enough. Are you suggesting that the weight difference is significant enough for more integration and certification job when CJ1000A is ready?
We need to be careful when quoting wiki. Here is EASA certification document about LEAP-1A and 1C.
LEAP-1C's weight figure is quoted by wiki. It includes thrust reverser which is quite big chunk of structure although it does not include (hydrolic) fluid. I can't find wiki's figure for 1A though. But my point is that source like wiki present a over simplistic picture that can be misleading.
If everything related is put together, there may not be a difference.
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Absolutely correct. 1C weight here includes not only thrust reverser, but also this:
1A weight is only basic engine weight + fluids... no reverser, no plug, no nozzle.
In fact I won't be surprised if at the end of the day 1C will turn out to be lighter than 1A due to more advanced nacelle.
Just look at the debate before your post. The thing is we simply do not know. Not when we do not have decent numbers measured by the same yardstick to compare both.
I have seen a lot of people in Russia do the same thing with regards to PD-8 vs SaM-146 engine. They claim PD-8 engine is much heavier, but they are comparing the weight of PD-8 engine with the shell around the engine and the nacelle, to just the SaM-146 engine.
You think so because the thrust figures quoted by wiki? I have said that the weight figures are misleading. The thrust figures on wiki are also misleading according to the EASA document. The bottom line is that all of them are the SAME engine with different adaptations for different demands, they are not one version improved over the other, therefor no one is better than the other.
If there is one varient of CFM LEAP being "inferior" it is the 1B variant used by Boeing 737 because it has a much smaller fan (lower bypass ratio) due to the lower mounting point. This leads to 1B having lower thrust and higher fuel consumption. The "inferiority" is not due to the technology in 1B but the old airframe design of 737 therefor I use quotation marks.
From EASA document.
1. The electricity generation of 1C is higher than 1A, therefor its thrust will be lower than 1A. There can be other hiden usages of power from the engine that futher skew the figure on surface, such as but not limited to percentage of air from the bypass (fan) duct to pressue the cabin, higher pressure is more comfortable to passengers but lower the engine thrust.
2. Most variants of 1A have LOWER thrusts (Take-Off and Max continuous) than 1C. The "best" of 1A are due to its lower electricity generation.
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IMHO China shouldn't waste too much time with EASA certification. It is fine if they get it, but much better would be to establish the credentials of its own certification authority and improve relations between it and other Global South countries.
EASA certification is not for export to Europe, but to increase the credibility to Global south countries. Let's say you are trying to sell to Saudi Arabia. Would you not want EASA certificate? After all, Saudis cannot fully replace 737s in their fleet unless C919s are allowed to fly into Europe. There is also just the overall reputation effect of having EASA certificate.