Bjorn’s Corner: Why hybrid cars work and hybrid airliners have challenges

By Bjorn Fehrm

June 14, 2019, ©. Leeham News: In last week’s Corner we discussed why aircraft with batteries as an energy source will be short ranged for decades to come. The battery energy density is too low and it won’t change appreciably over time.

Now we look at the challenges hybrid transport aircraft face when competing with today’s turbofan airliners.

The Zunum Hybrid electric airliner. Source; Zunum.

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Bjorn’s Corner: Why Electric Cars work and Airliners don’t

By Bjorn Fehrm

June 7, 2019, ©. Leeham News: In last week’s Corner I wrote: “The reason electric cars work and airliners don’t is the Sky lacks Stoplights“.

The discussion was part of my previous series on Electric aircraft, but it was in the comment section. Here is a more exhaustive run through of the main reasons.

Figure 1. The Tesla electric car which is a functioning replacement for a combustion engine car. Source: Tesla.

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Bjorn’s Corner: Electric aircraft, the first fall on the Hype curve

Bjorn’s Corner

May 31, 2019, ©. Leeham News: Last week the new Airbus CTO, Grazia Vittadini, said we should not expect electric aircraft anytime soon when presenting at Airbus Innovation days. What is realistic is hybrid developments, not battery-based designs.

After having made the basic checks about Electric aircraft in my Corner series 18 months ago, this was music to my ears. Finally, someone was curbing expectations.

Figure 1. The Gartner technology hype curve. We are somewhere in the first peak.  Source: Gartner.

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Bjorn’s Corner: Airbus about Urban Air Mobility: Stop dreaming, Start making

By Bjorn Fehrm

May 24, 2019, ©. Leeham News: “Stop dreaming, Start making” was the angle of Airbus responsible for Urban Air Mobility (UAM), Eduardo Dominguez Puerta, presenting during Airbus Innovation days in Toulouse this week.

He also said, over 90% of the present UAM projects will not make it into a certified operational platform. Here’s why.

Figure 1. The motivation for Urban Air Mobility is strong. Source: Airbus.

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Bjorn’s Corner: Why I wouldn’t hesitate to fly on the MAX after the fix

By Bjorn Fehrm

May 18, 2019, ©. Leeham News: We are now two months into the grounding of the Boeing 737 MAX because of MCAS. Boeing announced yesterday it has finished the work on the fix and it’s now ready for FAA certification flights. Once FAA has certified the fix, the 737 MAX will return to the sky. At least this is how it used to be.

A lot of hesitation and distrust has come into the system since the March 13th grounding. Here’s why I wouldn’t hesitate to fly on the MAX after the fix.

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Bjorn’s Corner: Time to reassess the safety standards for our airliners

By Bjorn Fehrm

April 26, 2019, ©. Leeham News: In the wake of the 737 MAX crashes the standards to which Boeing and the FAA qualified and approved the 737 MAX MCAS function is questioned.

FAA has called the world’s aviation regulators to a meeting on the 23rd of May to discuss how the revised MCAS function will be approved. But it’s time to discuss more than how the updated MCAS shall pass.

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Bjorn’s Corner: MCAS fix on the way

By Bjorn Fehrm

April 19, 2019, ©. Leeham News: Boeing’s CEO Dennis Muilenburg yesterday flew with the final version of the updated MCAS software on a 737 MAX. It will now enter certification flights, having completed 120 Boeing test flights.

Here my perspective on MCAS and the overall Boeing 737 safety record.

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Bjorn’s Corner: We are getting worldwide flight surveillance

Bjorn’s Corner

April 12, 2019, ©. Leeham News: In the wake of the 737 MAX accidents an important news event last week went almost unnoticed. After years of preparation, the worldwide coverage of ADS-B via Satellite receivers started with a trial service over the Atlantic.

It’s the Aireon Company which started the trial on April 2nd together with Nav Canada and UK’s NATS (National Air Traffic Control Services).

Figure 1. The Aireon worldwide Sattelite ADS-B receiver system. Source: Aireon.

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Bjorn’s Corner: ET302 crash report, the first analysis

Bjorn’s Corner

April 05, 2019, ©. Leeham News: The preliminary accident report of the ET302 crash was released yesterday. It confirmed what we wrote about earlier in the week, the pilots followed the prescribed procedure to stop MCAS. Yet they didn’t make it.

Part of why we presented Wednesday. Here follows additional analysis after studying the information in the Preliminary Crash Report.

Figure 1. The general Flight Data Recorder trace from ET302. Source: ET302 preliminary report.

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Bjorn’s Corner: The Ethiopian Airlines Flight 302 crash, Part 3.

By Bjorn Fehrm

March 23, 2019, ©. Leeham News: Boeing this week presented how they plan to get the 737 MAX back in the air again. MCAS has a fix.

We look at what the fix tells us about the first implementation and the rationale behind its implementation.

Figure 1. The improved Pilot’s Primary Flight Display presented Wednesday. Source: Boeing.


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