Leeham News and Analysis
There's more to real news than a news release.
Fundamentals of airliner performance, Part 2.
By Bjorn Fehrm
In our first article on how to understand the fundamentals that make up airliner performance we defined the main forces acting on an aircraft flying in steady state cruise. We used the ubiquitous Boeing 737 in its latest form, the 737 MAX 8, to illustrate the size of these forces. 
Here a short recap of what we found and then some more fundamentals on aircraft’s performance, this time around the engines:
When flying steady state (Figure 1) we only need to find the aircraft’s drag force to have all important forces defined.
Figure 1. Elementary forces acting on an aircraft at cruise. Source: Leeham Co.
The lift force is given as equal to and opposite to the aircraft’s weight and the tail downforce that we need to add to this was small. We also presented the two classes of drag that we will talk about:
- Drag independent of lift or as we often call it drag due to size as almost all drag components here scale with the aircraft’s size.
- Drag due to lift or drag due to weight as we call it as this drag scales with weight when one flies in steady state conditions.
We could see that the aircraft’s flight through the air created a total drag force of 7900 lbf, Figure 2 ( lb with an f added as we prefer to write it as this is a force and not a measure of mass. Mass we denote with just lb or the metric units kg or tonne = 2205 lb).
Figure 2. Drag of our 737 MAX 8 and how it divides between lift and non lift drag. Source: Leeham Co.
We also learned that if the drag is 7900 lbf then the engine thrust is opposite and equal. It is then 3950 lbf per engine when cruising at our mean cruise weight of 65 tonnes or 143.000 lb on our 1000 nm mission. Drag due to size consumes 63% of our thrust and drag due to weight 37%. Read more
Zhuhai Airshow: China’s aircraft industry is gaining speed
The 10th Chinese airshow at Zhuhai opened today. It was a day with fewer announcements than expected from the usual suspects (Airbus, Boeing…) but the Chinese industry did not disappoint. China is now showing more and more of its coming might as a player on the aeronautics arena.
The most prominent displays at this show were on the military side, where China has two stealth aircraft projects flying (the large Chengdu canard J-20 and the smaller Shenyang J-31) while their canard Chengdu J-10 was flying the display circuits overhead (Figure 1).
Figure 1. Chinas latest fighter developments; the J-31 and J-20 stealth fighters and the canard J-10. Source: China internet.
All aircraft are of latest structural and aerodynamic design if not in engines and systems. This is a big difference to previous shows where the Russian Sukhoi and MIG aircraft and their local copies did the flying display until 2008. Since then everything has changed and now China and USA are the only countries in the world with two different stealth designs flying. USA has one in operation (F-22) and one close to (F-35) whereas China still has many years to go until they have their new aircraft operational. But it is significant that the old aeronautical behemoths Europe and Russia have none respective one (PAK-50) stealth fighter in flight test.
Odds and Ends: 787 donation; Alenia sues Bombardier over CSeries; 2016 777 delivery slots opening up
787 donation: The Boeing Co. handed over 787 test airplane #3 (ZA003) to the Museum of Flight Saturday in an elaborate ceremony marking an unprecedented donation of a modern airliner to an aviation museum.
Boeing 787 ZA003, which went on a world sales tour, was donated to Seattle’s Museum of Flight Nov. 8, 2014. The logos of customers bracket the #2 door. Photo by Leeham News and Comment. click to enlage.
To be sure, the donation was made possible by the fact that ZA003 (and 002 and 001) can’t be sold due to the massive rework necessary, and these three airplanes have been written off for more than $2bn. But this doesn’t make the event any less significant.
Del Smith, aviation icon, dies
Del Smith, an icon in aviation for decades, died in Oregon.
Smith was the founder of Evergreen Aviation, an MRO in Arizona and the highly regarded air museum that houses the Spruce Goose in Oregon.
Evergreen cargo airlines was widely believed at one time to be owned by the CIA. The MRO in Marana (AZ) was one of the top airliner graveyards. It is now under new ownership.
The museum in McMinville (OR) has been regarded as one of the finer ones in the country. It’s been mired in controversy over allegations Smith failed to pay for the Spruce Goose, the huge wooden airplane designed by Howard Hughes, per the contract to buy the airplane.
Evergreen Airlines was the first operator of the Boeing 747 Dreamlifters, a contract now held by Atlas Air.
We met Smith on several occasions. Always affable, Smith never admitted (to us, anyway) whether Everegreen had CIA connections.. His enthusiasm for aviation history was always infectious.
Odds and Ends: Rescuing a polar bear cub; new turbo-prop, sort of
Rescuing a polar bear cub: Long-time readers of this column know we’re fascinated with polar bears, so when we received the following press release, we couldn’t help but share the story with you.
Mi-26 saves polar bear cub
The crew of a Russian Mi-26 military helicopter from the Eastern Military District Army Aviation airbase saved a baby polar bear from starving to death in the Arctic, after the young bear became separated from its mother.
The Mi-26 was carrying out a routine transport flight in the Arctic zone, delivering goods from Anadyr to Wrangel Island, when one of the crew spotted a lone polar bear cub wandering along the Chukotka shore. The crew carried out several sweeps of the area, but there was no trace of the cub’s mother. The decision was therefore taken to pick up the polar bear cub.
Airbus, Boeing freighter demand forecasts optimistic, says P2F company
Special to Leeham News
By Cliff Duke
LCF Freighter Conversions
I have mapped out below the last five years of OEM forecasts (Boeing World Air Cargo Forecasts and Airbus Global Market Forecast data) on widebody conversions calibrated against the actual widebody aircraft conversions redelivered and the current respective order books. If this is half right, it suggests that if in 2010 you were a widebody aficionado and you set your stall out on the Boeing or Airbus 20 year forecasts published that year, you would, reading their 2014 forecasts, now be looking at a 46% reduction in that forecast and your 2010 business plan might be developing cracks.
In terms of performance to date, a quarter the way through the 20 year 2010 forecast (assuming an equal spread of conversions across the 20 years of the forecast) we are currently some 70 conversions behind the Boeing 2010 forecast, a 50% drop off from where we thought we would be. It looks unlikely that the variance can be recovered in the remaining 15 years of the 2010 forecast. In the meantime Boeing and Airbus have updated their 20 year forecasts, and the overall drop off forecast is significant.
One question is, have the OEMs now updated their outlooks enough? Could both forecasts still be too optimistic and could our 2010 investor be looking at a further 50% drop off when revisiting the OEM forecasts in five years’ time (2020)?
Figure 1. LCF Conversions says the Airbus and Boeing 20 year freighter demand forecast have been substantially over-optimistic. Click on image to enlarge for crisp image. Source: LCF
MD-11’s final pax flights contains lessons for McBoeing as NSA targets 2030
- Boeing’s CEO, Jim McNerney outlines his vision for the next New Small Airplane in this report from Reuters. We believe this will cement Airbus’ dominance in the single-aisle market for the next 15 years.
A retrospective of the McDonnell Douglas MD-11 and the last passenger flights for enthusiasts contains lessons for Boeing, or McBoeing as many still call the combined companies.
Aviation Week’s story by highly respected technical reporter Guy Norris contains this key paragraph:
Despite its many technical advances, most notably on the flight deck, the MD-11 was handicapped from birth by its derivative dependence on the obsolete DC-10. Created on the eve of the era of the fuel-efficient big twin, the MD-11 emerged as a committed three-engined product too early to be redesigned around the new generation of big turbofans. Notoriously starved of serious investment by its ‘MD’ leadership, all attempts by the Douglas product development group to develop either twin-engined or larger stretched versions of the MD-11 sadly came to nothing. (Emphasis added.)
Boeing, burned mightily by the twin program development debacles of the 787 and 747-8, isn’t about to take any more “moonshots,” says CEO Jim McNerney. Yet Boeing is now at a crossroads where another moonshot is needed.
Boeing 737 MAX 8 as a long and thin aircraft and how it fares in general versus Airbus A320neo.
Subscription required.
By Bjorn Fehrm
Introduction
Over the last weeks we have looked at Boeing’s 757 replacement possibilities on its long and thin network niche, including a ground breaking launch interview for the A321neoLR with Airbus Head of Strategy and
Marketing, Kiran Rao. In the series we have seen that the A321neo has the potential to replace the 757-200 on long and thin international routes. Boeing’s equivalent single aisle entry, 737 MAX 9, has problems to extend its range over 3,600nm. It is too limited in the weight increase necessary to cover the longer range.
Many have asked how the less- restricted Boeing 737 MAX 8 would fare, suitably equipped with the necessary extra tanks. This is the subject of this week’s sequel on the theme long and thin. At the same time we look at Airbus entry in this segment, the A320neo, to see how it stacks up to the 737 MAX 8, both in their normal 1,000 to 2,000nm operation and then also in a long and thin scenario.
Let’s first summarize what we found so far in our four articles around the Boeing 757 and its alternatives:
Summary
Figure 1. Boeing 737 MAX 8 overlaid with Airbus A320neo. Source: Leeham Co.
Read more
4 Comments
Posted on November 9, 2014 by Bjorn Fehrm
Airbus, Airlines, Boeing, CFM, GE Aviation, Leeham Co., Leeham News and Comment, Pratt & Whitney, Premium, Rolls-Royce
737, 737 MAX, 737NG, A320, A320NEO, Airbus, Boeing, CFM, Pratt & Whitney, Rolls-Royce