Leeham News and Analysis
There's more to real news than a news release.
Leeham News and Analysis
- Boeing’s 737 North Line and the Everett factory: in transition now June 9, 2025
- Bjorn’s Corner: Air Transport’s route to 2050. Part 25. June 6, 2025
- New RISE powerplant benefits from decades of GE research and development June 5, 2025
- Engine makers emphasizing durability, reliability June 4, 2025
- Boeing CEO: Lessons learned are key to certification of 737-7/10 and 777X June 2, 2025
Bjorn’s Corner: Supersonic transport revival, Part 12
October 26, 2018, ©. Leeham News: In the previous Corner we discussed the noise challenge an SST engine has. To be effective at Supersonic speed it needs a high Specific Thrust (a fast jet out the back) but this creates Takeoff and Landing noise.
We now look at some key data for SST engines.
Figure 1. The GE Affinity medium bypass Turbofan for Aerion AS2. Source: GE.
Bjorn’s Corner: Supersonic transport revival, Part 11
October 19, 2018, ©. Leeham News: In the last Corner we discussed the temperature challenges an SST engine faces.
Now we address an even larger problem for SST engines, the takeoff and landing noise.
Figure 1. The GE Affinity SST Turbofan for Aerion AS2. Source: GE Aviation.
Bjorn’s Corner: Supersonic transport revival, Part 10
October 12, 2018, ©. Leeham News: In the last Corner we discussed the challenges of the nacelle outlet for an SST (SuperSonic Transport). Now we will discuss SST engines and what are the key technical challenges for these engines.
We start this week by looking at some design constraints for the engine which we don’t have in Subsonic airliner engines.
Figure 1. A generic mixed Turbofan SST engine with ConDi nozzle. Source: GasTurb. Read more
Bjorn’s Corner: Supersonic transport revival, Part 9
By Bjorn Fehrm
October 5, 2018, ©. Leeham News: In the last Corner we discussed the challenges an efficient inlet poses for an SST (SuperSonic Transport).
Now we go to the back of the nacelle and look at the outlet.
Figure 1. The Concorde nacelle with intake and nozzles. Source: Google images.
Bjorn’s Corner: Supersonic transport revival, Part 8
By Bjorn Fehrm
September 28, 2018, ©. Leeham News: In the last Corner we started looking at the biggest challenge for an SST, the powerplant. We first discussed the most fundamental problem of the engine, the level of Ram drag for an SST engine.
Now we continue with the challenges of the Nacelle. This week we talk intakes.
Figure 1. The Concorde nacelle with its Multi-Shock inlet. Source: Google images.
Bjorn’s Corner: Supersonic transport revival, Part 7
By Bjorn Fehrm
September 21, 2018, ©. Leeham News: In the last Corner we looked at the heating of the aircraft when cruising at high Mach.
Now we will address the biggest problem for supersonic airliners, the engines and nacelles.
Figure 1. The Concorde engine and nacelle. Source: Google images.
Bjorn’s Corner: Supersonic transport revival, Part 5
By Bjorn Fehrm
September 7, 2018, ©. Leeham News: In the last Corner we looked at the drag hump which is created by several supersonic effects when an SST (SuperSonic Transport) passes Mach 1.
Now we will look at other aerodynamic problems facing an SST.
Figure 1. The Aerion AS2 SST with its main systems. Source: Aerion Supersonic.
Bjorn’s Corner: Supersonic transport revival, Part 4
By Bjorn Fehrm
August 31, 2018, ©. Leeham News: In the last Corner we discussed supersonic lift wave drag and how suddenly the length aspect ratio is more important than wingspan aspect ratio.
Now we talk about the problem of going from subsonic to supersonic flight.
Figure 1. The Supersonic drag hump. Source: Wikipedia.
Bjorn’s Corner: Supersonic transport revival, Part 3
By Bjorn Fehrm
August 24, 2018, ©. Leeham News: In the last Corner we discussed how supersonic wave drag can be higher than any other drag for a blunt fuselage trying to fly at supersonic speeds. If we try to fly supersonically with a Dreamliner fuselage, the volume wave drag is four times as large as the whole Dreamliner drag when flying at its normal cruise speed.
Besides wave drag based on bodies volumes we also have wave drag when we angle lift surfaces like wings against air to create lift.
Figure 1. The last Supersonic transport, the Concorde. Source: Wikipedia.
Bjorn’s Corner: Supersonic transport revival, Part 2
By Bjorn Fehrm
August 17, 2018, ©. Leeham News: In the last Corner we outlined several challenges facing a supersonic airliner or business jet.
We will now go through these challenges one by one. We start with the aerodynamic challenge.
Figure 1. The last Supersonic transport, the Concorde. Source: Wikipedia.