MC-21 and C919 compared. Part 3.

By Bjorn Fehrm

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Introduction

June 15, 2017, ©. Leeham Co: We continued the comparison of Irkut’s MC-21 and COMAC’s C919 last week with an analysis of the cabins and systems. The week before, we compared project time plans, structures and aerodynamics.

Now we finish with an analysis of the economics of the aircraft.

Summary:
  • The MC-21 is the more advanced aircraft of the two. It uses carbon composites for the wings and empennage.
  • Coupled with more refined aerodynamics, the MC-21 offers a higher efficiency than the more classical C919.

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MC-21 and C919 compared. Part 2.

By Bjorn Fehrm

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Introduction 

June 08, 2017, ©. Leeham Co: We started the comparison of Irkut’s MC-21 and COMAC’s C919 last week. We compared project time plans, structures and aerodynamics.

Now we continue with the comparison of cabin capacities and systems.

Summary:

  • The C919 cabin is a slightly longer copy of the Airbus A320 cabin. MC-21 sets new standards for cabins in the single aisle segment.
  • Both aircraft use Western systems to ease development and improve in-service reliability.

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Aeroflot, the route to a modern airline, Part 2

By Bjorn Fehrm

April 19, 2017, ©. Leeham Co: In our second article about Aeroflot, the Soviet Union flag carrier that transformed to a modern airline, we will cover the period from the fall of the Soviet Union until 2010.

This was the difficult period for all participants. The old structures no longer existed and were replaced with… nothing, followed by uncertainty and a long struggle to get back to normal.

Figure 1. IL-96-300, a Soviet long range aircraft which stayed in the Aeroflot fleet until 2014. Source: Aeroflot.

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Bjorn’s Corner: Aircraft engines, sum up

By Bjorn Fehrm

April 14, 2017, ©. Leeham Co: We’ve been talking engines on Fridays since October 2016. The Corners covered several areas, from technologies to operations.

And we could go on and dig deeper. But we will move on.

Before we go, we sum up what we have learned in the 24 Corners around airliner Turbofans.

Figure 1. Principal picture of a three-shaft wide-body turbofan. Source: GasTurb.

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Bjorn’s Corner: Turbofan engine challenges, Part 3

By Bjorn Fehrm

By Bjorn Fehrm

November 12, 2016, ©. Leeham Co: In our trip through a modern turbofan airliner engine and its technologies, we looked last week at the engine intake and the fan. We now continue with the compressor parts.

As compressors and turbines use the same principles (but in opposing ways), we will look at these principles this week and how their roles in the engine create their special characteristics.

trent-xwb-model-stations_

Figure 1. Stylistic cross section of a three-shaft turbofan with section numbers. Source: GasTurb.

As before, to make things concrete, we use a GasTurb simulation of a Rolls-Royce Trent XWB 84k engine to look at practical data when needed. As before, I have no specific knowledge about the engine and will not use any data outside what is public information.

The GasTurb cross section of a three-shaft turbofan is shown in Figure 1. We will examine the sections between station numbers (22) and (3) and (4) and (5) in the general discussion of compressors and turbines. We will then look at some data for common compressors. Read more

Bjorn’s Corner: The Engine challenge

 

By Bjorn Fehrm

By Bjorn Fehrm

October 21, 2016, ©. Leeham Co: In our Corners on East bloc aeronautical industries, we could see that the hardest part to master in a new civilian airliner is the engine.

Both new airliners from Russia and China (Irkut MC-21 and COMAC C919) start their lives with Western engines.

Why is this so? What are the challenges that make engines harder to create than aircraft?

leap-1c-engine

LEAP-1C which will be standard engine on COMAC C919. Source: COMAC.

We will spend several Corners on the main reasons that airliner engines are harder to do than aircraft. Read more

Bjorn’s Corner; The Engine Research Institutes

 

By Bjorn Fehrm

By Bjorn Fehrm

October 14, 2016, ©. Leeham Co: In our Corners on East bloc aeronautical industries, we will now look at the role of the Research Institutes in Russian and Chinese civil aircraft engine development.

The Russian engine industry is organized similarly to the aircraft industry. It has a powerful research organization which has a much larger role than research organizations in the West.

A large part of fundamental design work and testing is done at the research institute and not at the design bureau level, Figure 1.

ciam-altitude-testing-of-pd-14-side

Figure 1. PD-14 engine altitude testing at the Central Institute of Aviation Motor Development (CIAM) in Moscow. Source: CIAM.

The Chinese organization of the engine industry is similar, the difference being that the research organizations are organized within the giant AVIC (Aviation Industry Corporation of China) grouping, rather than reporting to the state via a research organization path. Read more

Russian-Chinese wide-body: Program responsibilities

By Bjorn Fehrm

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Introduction

September 29, 2016, ©. Leeham Co: We will now finish our series about the Russian-Chinese wide-body with looking at who will have what role in the program.

Russian-Chinese widebody

Figure 1. Concept for new wide-body airliner. Source: United Aircraft.

As we described in the initial article, “Background and outlook,” Russia and China have vastly different competencies when it comes to making a state of the art wide-body aircraft.

Russia has made airliners since the 1930s, including wide-body jets. China did not design its own jet aircraft (military or civil) until the mid-1980s. Most of the aircraft produced still today in China have their origin in Russian designs.

At the same time, we saw in the article about the market demand for the aircraft that the Chinese market is 90% of the home market. This makes for China demanding important parts of the aircraft’s production, and China has the money to invest in production facilities.

All this will influence how different parts of the project will be shared between Russia’s United Aircraft Corporation (UAC) and Commercial Aircraft Corporation of China (COMAC).

Summary:

  • Russia and China enter the wide-body project with widely different knowledge bases.
  • Russia has long time knowledge on how to develop and produce aircraft and their engines.
  • China on the other hand has the market for the aircraft.
  • China also know a lot about serial production and have money to invest. Read more

Bjorn’s Corner; The Russian civil aircraft engine companies

 

By Bjorn Fehrm

By Bjorn Fehrm

September 23, 2016, ©. Leeham Co: In our Corners on East bloc aeronautical industries, we now look at the main Russian civil aircraft engine companies. As with the aircraft side, there is one overall Russian engine company since 2008, United Engine Corporation (UEC), Figure 1.

This is a state-owned holding which incorporates 80%of the gas turbine engine companies from the Soviet times, employing 80,000 people.

The aim is to coordinate and optimize Russia’s engineering and production resources around present and future gas turbine engines for Aeronautical, Naval and Stationary use.

uec-full

Figure 1. Engine companies in United Engine Corporation. Source: UEC.

Soviet and Russian engines have historically been named after their chief designer in the design bureau. We will now describe the main entities in UEC that work with airliner engines. Read more

Russian-Chinese wide-body: Aircraft performance

By Bjorn Fehrm

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Introduction

September 19, 2016, ©. Leeham Co: In Part 4 of the article series, we put together an assumed complete Chinese-Russian wide-body aircraft with fuselage, wing, engines, etc. It is now time to understand what kind of performance that can be expected, given the data we have from the wide-body partners, Russia’s United Aircraft Corporation (UAC) and the Commercial Aircraft Corporation of China (COMAC).

Russian-Chinese widebody

Figure 1. Concept for new widebody airliner. Source: United Aircraft.

We will combine these data with the ones we have deduced as plausible to fill the gaps, given the time frame and technology level that UAC and COMAC intend to use.

Out will come a first estimate of what kind of performance such an aircraft can have in terms of efficiency and payload versus range capability.

Summary:

  • We can use all the data we have gathered to make a first estimate of the efficiency of the Russian-Chinese wide-body.
  • We also have enough information to do a first payload-range diagram and to compare that with the diagram for Boeing’s 787-9.

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