By Bjorn Fehrm

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Introduction

April 25, 2016, ©. Leeham Co: We will now finish our series where we look into how big an undertaking a CS300 stretch to a 150 seater would be for Bombardier.

The C Series existing models, the CS100 and CS300, were designed with the CS300 as the main family member. That makes a stretch to a CS500 a pretty straight-forward job from a wing perspective, only minor adjustments are needed.

The problem area for the stretch is the fuselage. The C Series is a five abreast aircraft and at 150 seats the aircraft will have more than 30 seat rows. The resulting long fuselage limits the available rotation angle at takeoff.

Having discussed the different actions that can be taken to handle this problem in Part 2, we will now check the implications for the takeoff field length with our performance model. The model will also show if the engine takeoff thrust needs to be increased.

Finally, we will use the model to estimate the fuel consumption and the range of a CS500 derivative.

Summary

• A CS500 derivative made from the CS300 is a pretty straight-forward stretch project.
• Special care has to be taken with the risk for tails strikes from a longer fuselage.
• With the discussed actions in place, the field performance of a CS500 is still very good, even though it can't compete with a CS300.
• The range would be less than a CS300 but the aircraft would still be capable of five hour missions.
• Fuel consumption would be higher per trip but lower per seat than a CS300. It would give existing 150 seaters strong competition on efficiency.