The Anonymous Widower

DHL Express Determinedly On Course To Achieve Net-Zero Emissions

The title if this post is the same as that of this article on The Lodestar.

This was the introductory paragraph.

DHL Express chief executive John Pearson came out with all guns firing when detailing the firm’s efforts to hit net-zero by 2050, during a press junket this week.

The rest of the article is basically in three sections.

The Use Of Sustainable Aviation Fuel (SAF)

Summed up by three sentences.

“When it comes to sustainable aviation fuel (SAF), we know this is expensive, but we have also put a big chunk of change into this,” he said.

By the end of the year, we want 2% of flights fuelled by SAF.

DHL has bought 15% of all globally available SAF

DHL seem to have a comprehensive policy on the use of SAF.

This reinforces my view that SAF will be important.

Alternative Approaches

This paragraph sums up some of the more alternative approaches DHL are looking at.

SAF use forms only one part of the migration to net-zero: fleet renewal; decarbonising ground handling; a fuel optimisation programme; and the use of electric aircraft, following the successful September trial over Seattle of the Alice e-cargo plane, are all critical.

I suspect there are other alternative approaches.

Fleet Renewal

The last two paragraphs talk about fleet renewal.

Fleet renewal comes after a particularly pronounced moment of growth for the company: it added 10 widebody and 70 small- and medium-body planes during the pandemic.

Described by Boeing as one of the most “fuel-efficient” aircraft on the market, thanks to its twin-engine design, the 777 freighter forms a central part of DHL Express’ renewal plans, said Mr Pearson, adding that 28 were on order.

With 28 777 freighters on order, DHL will need a lot of SAF.

A Last Thought

Given the size of DHL’s fleet, which in their Wikipedia entry is given as 197, seventy-three of which are narrow bodies, I am surprised that no dedicated zero-carbon small or medium-sized cargo aircraft, except for the Alice is under development.

Perhaps, in areas like Europe, this niche is being taken by rail or perhaps by Airbus’s proposed hydrogen-powered ZEROe Turbofan.

I wrote in detail about this hydrogen-powered aircraft in Could An A320 neo Be Rebuilt As A ZEROe Turbofan?.

Airbus say that the passenger version of the ZEROe Turbofan could handle up to 200 passengers, despite having a large hydrogen tank in the rear fuselage.

The cargo capacity of a ZEROe Turbofan would probably be a bit smaller than say the latest Airbus A321 or Boeing 737, but if the hydrogen-powered aircraft was built to accept a stretch, I wouldn’t be surprised to find it was a viable aircraft for DHL, with a fuselage stretch!

It would surely help passengers of future hydrogen-powered aircraft, overcome their fear of an aircraft fueled by hydrogen.

The ZEROe Turbofan is quoted as having a range in excess of two thousand nautical miles, so it would have Europe and North America fairly well covered.

I also wouldn’t rule out use of Airbus’s proposed hydrogen-powered ZEROe Turboprop for flying cargo.

It would have a smaller capacity than the ZEROe Turbofan.

  • It would have a useful range of over a thousand nautical miles.
  • I feel that both ZEROe aircraft have the same fuselage cross-section, which could ease cargo handling, by using the same equipment for both aircraft.
  • I also feel that both ZEROe aircraft will have the same cockpit, which should reduce crew costs.

I feel that smaller cargo aircraft will play a large part in the development of hydrogen-powered aircraft.

If the plans of some companies and individuals work out, hydrogen might be a better alternative financially to SAF.

March 18, 2023 Posted by | Transport/Travel, Hydrogen | , , , , , , , | Leave a comment

Zero-Carbon Emission Flights To Anywhere In The World Possible With Just One Stop

The title of this post, is the same as that of this press release from the Aerospace Technology Institute.

This is the first sentence of the press release.

Passengers could one day fly anywhere in the world with no carbon emissions and just one stop on board a concept aircraft unveiled by the Aerospace Technology Institute (ATI) today.

These three paragraphs describe the concept.

Up to 279 passengers could fly between London and San Francisco, USA direct or Auckland, New Zealand with just one stop with the same speed and comfort as today’s aircraft, revolutionising the future of air travel.

Developed by a team of aerospace and aviation experts from across the UK collaborating on the government backed FlyZero project, the concept demonstrates the huge potential of green liquid hydrogen for air travel not just regionally or in short haul flight but for global connectivity. Liquid hydrogen is a lightweight fuel, which has three times the energy of kerosene and sixty times the energy of batteries per kilogramme  and emits no CO2 when burned.

Realising a larger, longer range aircraft also allows the concentration of new infrastructure to fewer international airports accelerating the rollout of a global network of zero-carbon emission flights and tackling emissions from long haul flights.

These are my thoughts.

The Airframe

This picture downloaded from the Aerospace Technology Institute web site is a visualisation of their Fly Anywhere Aircraft.

Some features stand out.

The wings are long, narrow and thin, almost like those of a sailplane. High aspect ratio wings like these offer more lift and stability at high altitude, so will the plane fly higher than the 41,000-43,000 feet of an Airbus A350?

I wouldn’t be surprised if it does, as the higher you go, the thinner the air and the less fuel you will burn to maintain speed and altitude.

The horizontal stabiliser is also small as this will reduce drag and better balance with the wing.

The tailfin also appears small for drag reduction.

The body is bloated compared to say an Airbus A 350 or a Boeing 777. Could this be to provide space for the liquid hydrogen, which can’t be stored in the thin wings?

The fuselage also appears to be a lifting body, with the wings blended into the fat body. I suspect that the hydrogen is carried in this part of the fuselage, which would be about the centre of lift of the aeroplane.

The design of the airframe appears to be all about the following.

  • Low drag.
  • high lift and stability.
  • Large internal capacity to hold the liquid hydrogen.

It may just look fat, but it could be as radical as the first Boeing 747 was in 1969.

The Engines

I suspect the engines will be developments of current engines like the Rolls-Royce Trent XWB, which will be modified to run on hydrogen.

If they are modified Trent engines, it will be astonishing to think, that these engines can be traced in an unbroken line to the RB211, which was first run in 1969.

The Flight Controls

Most airliners these days and certainly all those built by Airbus have sophisticated computer control systems and this plane will take them to another level.

The Flight Profile

If you want to fly any aircraft a long distance, you generally climb to a high level fairly quickly and then fly straight and level, before timing the descent so you land at the destination with as small amount of fuel as is safe, to allow a diversion to another airport.

I once flew from Southend to Naples in a Cessna 340.

  • I made sure that the tanks were filled to the brim with fuel.
  • I climbed to a high altitude as I left Southend Airport.
  • For the journey across France I asked for and was given a transit at Flight Level 195 (19,500 feet), which was all legal in France under visual flight rules.
  • When the French handed me over to the Italians, legally I should have descended, but the Italians thought I’d been happy across France at FL195, so they didn’t bother to ask me to descend.
  • I flew down the West Coast of Italy at the same height, with an airspeed of 185 knots (213 mph)
  • I was then vectored into Naples Airport by radar.

I remember the flight of 981 miles took around six hours. That is an average of 163.5 mph.

I would expect the proposed aircraft would fly a similar profile, but the high level cruise would be somewhere above the 41,000-43,000 feet of an Airbus A 350. We must have a lot of data about flying higher as Concorde flew at 60,000 feet and some military aircraft fly at over 80,000 feet.

The press release talks about London to San Francisco, which is a distance of 5368 miles.

This aircraft wouldn’t sell unless it was able to beat current flight time of eleven hours and five minutes on that route.

Ground Handling

When the Boeing 747 started flying in the 1970s, size was a big problem and this aircraft with its long wing may need modifications to runways, taxiways and terminals.

Passenger Capacity

The press release states that the capacity of the aircraft will be 279 passengers, as against the 315 and 369 passengers of the two versions of the A 350.

So will there be more flights carrying less passengers?

Liquid Hydrogen Refuelling

NASA were doing this successfully in the 1960s for Saturn rockets and the Space Shuttle.

Conclusion

This aircraft is feasible.

 

 

 

December 7, 2021 Posted by | Hydrogen | , , , , , , , , , | 2 Comments