COMAC C919
- Thread starter Deino
- Start date
China Eastern Airlines is seeking funding to pay for 4 C919 and 24 ARJ-21.
According to the disclosure, the airline will add 38 new aircrafts, including 4 C919, 24 ARJ21-700, 6 A350-900 and 4 B787-9. These aircrafts are expected to be delivered between 2022 and 2024.
Each C919 will cost 653 million yuans while the ARJ21-700s will cost 251 million yuans a piece. The airline will pay the unit price of 2.095 billion yuans and 1.931 billion yuans for the A350-900 and B787-9, respectively.
On May 8, The 7th C919 made by COMAC was spotted taxing on the 5th runway of Pudong Int'l airport. According to the social media, if everything goes by the plan, this aircraft will become the first of the said four C919 delivered to the Eastern Airlines. The airline will then fly it for service trial in May.
EDIT: Add info about the 7th C919.
According to the disclosure, the airline will add 38 new aircrafts, including 4 C919, 24 ARJ21-700, 6 A350-900 and 4 B787-9. These aircrafts are expected to be delivered between 2022 and 2024.
Each C919 will cost 653 million yuans while the ARJ21-700s will cost 251 million yuans a piece. The airline will pay the unit price of 2.095 billion yuans and 1.931 billion yuans for the A350-900 and B787-9, respectively.
On May 8, The 7th C919 made by COMAC was spotted taxing on the 5th runway of Pudong Int'l airport. According to the social media, if everything goes by the plan, this aircraft will become the first of the said four C919 delivered to the Eastern Airlines. The airline will then fly it for service trial in May.
EDIT: Add info about the 7th C919.
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Max flight height seems low which would limit the number of flight paths and be less efficient.
My uneducated guess is that it might be due to its shorter service range. I'd imagine that to fly at a higher cruise height might hurt feul economy and even take longer to finish the trip.
It is generally true that fuel burn decreases at higher altitudes (less dense air at altitude = less drag).
However a wide body jet at max takeoff weight can only cruise at roughly 28000 to 30000 feet (the floor of RVSM airspace starts at FL290). If it climbs/cruises higher than that, it reaches coffin corner where the subsonic stall speed meets the critical Mach number. A wide body can only cruise at higher altitudes once it burns off more fuel and becomes lighter, or if it takes off with a lighter traffic load. Most long distance flights use step climbs - the plane might start off the cruise at the high FL200s and step climb every couple hours till it reaches the mid to high FL300s or low FL400s.
An illustration of coffin corner - the plane (looks like a Boeing 777) is cruising at FL360 at Mach 0.77. The plane enters high speed buffet if it flies faster, and it stalls if it slows down. The coffin corner margin between high speed buffet and subsonic stall speed only increases as the weight of the aircraft decreases with fuel burn.
A plane primarily designed for short haul flights doesn't need to reach the high flight levels - let's say I'm operating from London to Paris, by the time I've reached the mid to high FL300s, I'm a couple miles away from top of descent. In essence I've "wasted" a boat load of gas reaching optimum cruise altitude in hopes for better cruise fuel economy.... except I'm only cruising for a couple minutes before having to start descending anyway after climbing that high up. I might've burned less fuel climbing up to the high FL200s to low FL300s, as compared to using full thrust trying to reach optimum cruise altitude and only briefly enjoying the benefits of climbing that high. That's why there really isn't a need for the C919 to have the capability to have high cruise altitudes, not when it's designed for short hop flights like Beijing to Shanghai or Chongqing to Shenzhen.
However a wide body jet at max takeoff weight can only cruise at roughly 28000 to 30000 feet (the floor of RVSM airspace starts at FL290). If it climbs/cruises higher than that, it reaches coffin corner where the subsonic stall speed meets the critical Mach number. A wide body can only cruise at higher altitudes once it burns off more fuel and becomes lighter, or if it takes off with a lighter traffic load. Most long distance flights use step climbs - the plane might start off the cruise at the high FL200s and step climb every couple hours till it reaches the mid to high FL300s or low FL400s.
An illustration of coffin corner - the plane (looks like a Boeing 777) is cruising at FL360 at Mach 0.77. The plane enters high speed buffet if it flies faster, and it stalls if it slows down. The coffin corner margin between high speed buffet and subsonic stall speed only increases as the weight of the aircraft decreases with fuel burn.
A plane primarily designed for short haul flights doesn't need to reach the high flight levels - let's say I'm operating from London to Paris, by the time I've reached the mid to high FL300s, I'm a couple miles away from top of descent. In essence I've "wasted" a boat load of gas reaching optimum cruise altitude in hopes for better cruise fuel economy.... except I'm only cruising for a couple minutes before having to start descending anyway after climbing that high up. I might've burned less fuel climbing up to the high FL200s to low FL300s, as compared to using full thrust trying to reach optimum cruise altitude and only briefly enjoying the benefits of climbing that high. That's why there really isn't a need for the C919 to have the capability to have high cruise altitudes, not when it's designed for short hop flights like Beijing to Shanghai or Chongqing to Shenzhen.
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This is what I meant but you explained it much better.
The 7th C919 and the first ever to be delivered for service successfully made its maiden flight on May 14.
According to Xinhua, the airplane, designated as B-001J, took off at 6:52am at the Pudong Int'l Airport. It landed safely at 9:54am after completing its maiden flight.
Guancha said Eastern Airlines and COMAC reached the deal in Shanghai on March 1. The first batch will consists of five C919. These aircrafts will be based in Shanghai.
Just two days ago, Guancha was saying that Eastern Airlines is seeking funding to buy four C919 among 38 aircrafts in total. Are we looking at two batches of 9 ordered in total?
According to Xinhua, the airplane, designated as B-001J, took off at 6:52am at the Pudong Int'l Airport. It landed safely at 9:54am after completing its maiden flight.
Guancha said Eastern Airlines and COMAC reached the deal in Shanghai on March 1. The first batch will consists of five C919. These aircrafts will be based in Shanghai.
Just two days ago, Guancha was saying that Eastern Airlines is seeking funding to buy four C919 among 38 aircrafts in total. Are we looking at two batches of 9 ordered in total?
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Agree that C919 is currently not commercially attractive to airlines. However, it is economically valuable to China and Chinese airlines. Availability of C919 as a third option will keep Airbus and Boeing honest in pricing and prevent any pricing collusion between the two, at least for single aisle jets.
It also enable China to sanction either Airbus or Boeing without making the other a monopoly is a good enough reason for China to see this commercial venture through in any means she can.
Of course, this is not lost to the US administration and will be a factor in their calculus of whether to sanction COMAC or not.
It’s better for CAAC to be careful then rush through. See what happened to the 737 max, I guess that hurts Boeing badly.
Some problems regarding materials used on C-919.
C-919 use third gen Al-Li alloy，which is heavily rely on import at the moment
The level of automation of composite material processing is quite low，lags far behind advanced countries.
ref:
国防军工国产大飞机系列报告之二：大飞机应用材料解析
C-919 use third gen Al-Li alloy，which is heavily rely on import at the moment
The level of automation of composite material processing is quite low，lags far behind advanced countries.
ref:
国防军工国产大飞机系列报告之二：大飞机应用材料解析