Archive for month: August, 2019

There is no denying that aviation has come very far technology-wise. In its early infancy, commercial aviation was an expensive and rather uncomfortable endeavor, as the turboprops that powered aircraft were loud, produced a ton of vibration and were limited in power, making passengers travel onboard an aircraft for a very long time.

As jet engines gained traction commercially, passenger comfort and airline operations improved dramatically. The first turbojets were more efficient, faster and most importantly – less noisy, thus providing a much more comfortable journey on board. Yet, aviation authorities and governments worldwide now seek to reduce how much noise aircraft produce with manufacturing limits, operational restrictions and regulations.

To counter aircraft noise pollution, the International Civil Aviation Organization (ICAO) has issued the Annex 16, which includes several chapters with noise restrictions. ICAO measures sound levels in Effective Perceived Noise (EPNdB), which relies on human annoyance, rather than general loudness.

Why is reducing aircraft noise pollution important?

Noise pollution can significantly impact the experience onboard. Airlines today aim to deliver the best product possible, including top of the line in-flight entertainment (IFE), catering, cabin layout changes and even lightning inside the aircraft are crafted in a way to make passengers as comfortable as if they were in their own home.

But one aspect of comfort for airlines is hard to control – noise. It puts carriers in a difficult position, as configuring a cabin in various ways can help to reduce the noise inside, but at the same time increase the weight of the aircraft and subsequently, boost operational costs.

According to a report by the Federal Aviation Administration of the United States (FAA), exposing a person to loud noise (higher than 90dB) for a prolonged period of time (eight or more hours per day) for several years “may cause permanent hearing loss”. A 2006 study highlighted that even at 65 dB(A), “humans become irritated from noise”. The same study tested sound levels on two Airbus A321 flights and the average noise levels in-flight were between 80-85 dB(A), just below the 90dB threshold, but way above the human annoyance sound level of 65 dB(A).

Furthermore, studies like the one by The University of New South Wales (UNSW Sydney) have shown that continuous exposure to noise can reduce the recognition of memory and cause a person to be more fatigued. A recent example of how fatigue can cause issues inside the cockpit is Air Canada Flight 759. the National Trasnportation Safety Board (NTSB), which investigated the horrofing close-call, concluded that fatigue most likely contributed to the crews’ decision making.

However, the A321 is a fairly new aircraft and is categorized under Chapter 4 in ICAO’s Annex 16, which allows for a maximum of 92.8 EPNdB for the aircraft. On average, it emits 88.3 EPNdB during a flyover. Newer aircraft are even under stricter noise restrictions and manufacturers have to comply with Chapter 14 regulations released in 2013. As a result, newer aircraft like the Airbus A321neo emits 83.7 EPNdB, while Boeing 737 MAX generates 82.6 EPNdB.

Yet people on board aren‘t the only ones affected by noise pollution – residents that live under busy flight paths experience a lot more issues related to sound pollution.

“It may be beautiful to look at, but not to live near”

Said one New York resident, as Concorde took off for the last time from New York’s John F. Kennedy Airport (JFK). While supersonic speeds, due to sonic booms, exaggerate the effect of sound pollution, the general consensus amongst residents living near airports is similar.

One study, which researched how aircraft noise affects a person’s health, concluded that continuous noise exposure may lead to “heart disease and hypertension”. Both consequences are exaggerated if the noise exposure is during the night, but “similar daytime exposure effects have also been identified”. Another study concluded that aircraft noise can also impact a child’s ability to learn, as “aircraft noise exposure at school or at home is associated with children having poorer reading and memory skills” – so much so, that even 5 dB can delay the average reading age by 2 months.

Aviation authorities are trying to mitigate the impact of aircraft noise pollution. The previously mentioned ICAO Annex 16 and its newest Chapter 14 are written with hopes to reduce the people living under “Day Night average sound Level of 55 dB” areas by 1 million between 2020 and 2036. World Health Organization (WHO) indicates that noise levels above 55 dB during the night affect the population, as it becomes “highly annoyed and sleep-disturbed” and is more prone to cardiovascular diseases.

FAA has also launched a project called Noise Quest, which includes educational material and research about the effects of aircraft noise pollution. The agency even helps airports to acquire land near their facilities if the acquisitions are done under “noise compatibility programs”, as noise regulations also restrict operations.

Restricting operations

Airlines are very strict regarding their costs, especially low-cost carriers. While one of the reasons that they do not operate the night is to conclude maintenance on their aircraft, airports also charge a lot more for flights that land or depart during the night.

For example, London-Gatwick Airport (LGW) imposes charges upon every aircraft that lands at the airport. One of the charges is related to noise. An aircraft, compliant with ICAO Annex 16 Chapter 14 base noise emissions has to pay $26.23 (£21.65) during a summer’s (April 1 – October 31) day (5 AM – 10:29 PM), but at night (10:30 PM – 4:59 AM) that sum increases to $460.52 (£378.69). Considering the fact that low-cost carriers operate under tight margins and try to avoid every cost as much as possible, airlines try to avoid landing during the night as much as possible.

To illustrate, an easyJet Airbus A19 registered G-EZIV completed six flights from and to London-Gatwick (LGW) on August 21, 2019, according to FlightRadar24 data. The aircraft started its day at 5:50 AM, avoiding the night time noise charges, but its last flight was late to depart from Bordeaux (BOD) by 11 minutes and it landed at 10:30 PM. As a result, easyJet was forced to pay nightly fees for the flight. Considering the fact that the airline has to pay for fuel, emission taxes, parking fees, service fees and many other costs imposed on aircraft, and keeping in mind that easyJet average revenue per seat is $61.65 (£50.71), those 11 minutes can be the crucial difference between a profitable flight and a loss-making flight.

Numerous airports around the world limit their operations during the night due to noise restrictions – according to ICAO, the number of international airports who restrict night time flying in some shape or form is 161, of which 107 are located in Europe. As a result, landing and departure slot times are becoming a valuable asset that can be worth almost as much as an aircraft – in early 2016, Oman Air paid $75 million for a pair of take-off and landing slots at London-Heathrow (LHR). Thus, airlines pay extra attention to schedule planning, as profitability can depend on minutes. Increasing capacity on routes can also be very difficult, if the route is congested by other airlines – if slots are limited, the initial costs of purchasing a landing slot can determine whether the airline is able to increase Available Seat Kilometers (ASK) in their network.

Nevertheless, aircraft manufacturers try to reduce the noise that aircraft emit as much as possible.

Help of the manufacturer

But noise reduction comes back to the manufacturers like Airbus or Boeing. Fuel efficiency is by far the most important aspect of a new aircraft, but noise reduction has become increasingly influential when airlines do decide to purchase an aircraft.

Lufthansa estimates that a new Airbus A350-900 produces between 40 and 50% less noise contour compared to its quad engine cousin, the A340. The aerodynamic shape of an aircraft can help reduce the noise on an aircraft as wind bypasses it, rather than hitting the aircraft. For example, a retracted landing gear during an approach or a landing can create noise, as the wind hits it. One more case is the Airbus A320 family – the aircraft emitted a “squeaky” sound during the approach. But a vortex generator under the wings can reduce the noise by up to 6 dB, which airlines began to retrofit on their A320s back in 2014.

However, engines are one of the major contributors to overall noise emitted by an aircraft and manufacturers use an array of ways to reduce the sound. Modern engines have higher bypass ratios, thus the engine itself consumes less air and produces less noise. Also, the air that bypasses the core of the engine is muffled by the air that has passed the engine fan and due to the high bypass ratio, a lot more air passes by the fan. Engine chevrons also help, as they smooth out the mixture of the hot air from the engine core and the cold air from the engine fan, creating a turbulence-free environment around the engine.

Airlines also retrofit their engines with hush kits, but these are mostly used on older, low bypass engines like on the Boeing 737-200, which still sees active service in Northern Canada.
Health concerns

All in all, the number one reason to reduce noise pollution is to improve the quality of life of the communities that live near airports or busy flight paths. As noise pollution is proven to have detrimental effects on health and the ability to work even in the cockpit, further reducing noise emissions is crucial. However, as the general public is still largely unaware of the harm that aircraft noise can cause, according to PARTNER, education is as important as advancements in technology.

Source: https://bit.ly/2MBBp5i

Image : Ceri Breeze

Air New Zealand is awaiting its last remaining out-of-service Rolls-Royce engines to return to operation in the upcoming months, the airline has revealed announcing its latest financial results. The flag carrier has been hit by several rounds of Rolls-Royce Trent 1000 problems that continue to affect its operations.

“Another important milestone will be the return of our remaining Rolls-Royce engines back into service, which we are expecting to happen in the coming months,” the airline has revealed in a statement. “This will enable us to bring further reliability back to our flying schedule and to utilise our most efficient aircraft in the optimum way”.

The Air New Zealand’s “most efficient” aircraft are 13 Boeing 787-9 Dreamliners that the carrier has in its fleet of 64 airliners. The airliners, while preferred by the airline for their fuel efficiency, have been plagued by engine problems.

In early 2016, the launch customer of the Boeing 787, All Nippon Airways (ANA), detected unusual corrosion in blades of intermediate-pressure turbine (IPT), resulting in early wear and cracking on Trent 1000 Package C engines. At the time, the company estimated that it would take roughly three years to replace the blades in all the affected engines.

Air New Zealand was among the affected airlines. It had to cancel flights, make scheduling changes and resort to leasing wide-body aircraft as maintenance issues with the Rolls-Royce Trent 1000 engines resulted in grounding of some of its Boeing 787-9 aircraft. However, the problems did not stop here.

In January 2019, early wear of the high-pressure turbine (HPT) blade of Trent 1000 TEN was also detected, prompting for more inspections. Some of the airline’s Dreamliners were already fitted with Trent 1000 TEN engines too. Moreover, “at least seven of Air New Zealand’s Trent 1000 TEN engines are replacements for the earlier model Trent 1000 “Package C” engines”, Australian Aviation estimates.

In August 2018, the airline already accounted $30 million to $40 million hit resulting from schedule changes prompted by the global Rolls-Royce engine issues. This year, it does not reveal the exact numbers, instead vaguely mentioning “a temporary increase in operating costs” in the face of the global Rolls-Royce engine issues.

In August 2019, Rolls-Royce announced it was getting close to fixing problems that affect its Trent 1000 engines. “We have made good progress on resolving the Trent 1000 compressor issue, though regretfully, customer disruption remains,” was written in a statement by the company.

Engines problems have not discouraged Air New Zealand from buying Dreamliners. In May 2019, the airline signed a firm agreement to purchase eight Boeing 787-10s with an option to increase the order up to 20 aircraft, as well as, rights that allow to switch from the larger 787-10 aircraft to smaller 787-9s. The deal is valued at $2.7 billion (at list prices) and the first airliners are expected to arrive in 2022.

But this time, instead of Rolls-Royce, the airline opted for GE Aviation’s GEnx-1B engines to power its new long-haulers.

At the moment, Air New Zealand website (last update three days ago) still warns passengers about possible schedule or aircraft changes due to Rolls-Royce Trent 1000 Package C engine problems on a “number of” their Boeing 787-9s.

The airline explains that earlier than expected maintenance checks on a specific part of the engine compressor are required as advised by Rolls-Royce, in conjunction with European regulator EASA. To solve the issue, it is leasing one Boeing 777-300 aircraft from EVA Air.

Source: https://bit.ly/2zdr5Yr

Image: Stanislav Fosenbauer / Shutterstock.com

Embraer has reinstated that its newest commercial jet, the E195-E2, is to enter service in the second half of 2019. Besides the launch customer Azul Linhas Aéreas Brasileiras, Spanish airline Binter Canarias is also to receive the first E195-E2 this year, the manufacturer states.

Embraer reiterated the E195-E2 plans in its financial results for the second quarter of 2019 statement, released on August 14, 2019.

According to the company, the E195-E2 flight tests revealed a 1.2% “lower than expected” fuel consumption, meaning that the new generation E195 uses 25.2% less fuel per seat compared to the current-generation E195. Embraer claims that maintenance costs of E195-E2 are also 20% lower.

The E195-E2 received Type Certification simultaneously from the Brazilian Civil Aviation Agency (Agência Nacional de Aviação Civil, ANAC), the U.S. Federal Aviation Administration (FAA) and European Aviation Safety Agency (EASA) in April 2019.

So far (as of June 30, 2019), Embraer has 124 firm orders of E195-E2 and 50 options. The latest orders were placed by the Nigerian airline Air Peace and carrier in-the-making Great Dane Airlines. With an order of 10 E195-E2s (and options for 20 more), Air Peace is to be the first African-registered operator of Embraer’s new-generation E-jets.

The E195-E2 is the largest commercial aircraft in Embraer’s portfolio. With a maximum range of 2,600 nautical miles, it can accommodate 120 seats in a two-class configuration or up to 146 in high-density variant. With a higher range and more seat rows than E195, the E195-E2 actually has little to do with the first generation of E-jets, as 75% of its systems are new, including engines, wing, landing gear, and full fly-by-wire.

Source: https://bit.ly/33HT0On

Image: Nattanon Tavonthammarit / Shutterstock.com

Airbus was competing with Boeing, McDonnell Douglas and Lockheed’s TriStar only in short and mid-hauls until 1993. But in the long-haul market, Boeing was robust with its 747 since 1970. To fill the long-haul market gap, Airbus designated the A340 to be a “true globe-trotter” that airlines could use on their longest routes. With better operating economics than the 747, the A340 was poised to take over the Queen’s throne as the king of long-haul flights.

On October 25, 1991, Airbus A340-300 made its maiden flight, before joining fleets of launch customers Air France and Lufthansa and officially commencing service in 1993. On November 10, 2011, Airbus announced that the company has finished the production of the once record-breaking quadjet and will not take on any more new orders. Merve Kara from AeroTime looks at the 18-years of history of the A340.

Record Breaker

Airbus A340 started out with a good beginning in 1993. On June 16, 1993, the aircraft, dubbed “World Ranger”, flew from the Paris Airshow to Auckland, New Zealand, and back in 48 hours and 22 minutes, breaking six world records, including the longest non-stop flight by an airliner. This record was broken by Boeing 777 on a 12,455.34 statute miles (20,044.20 km) flight from Seattle, the U.S., to Kuala Lumpur, Malaysia, in 1997.

Airbus developed four A340 variants: A340-200, A340-300, A340-500 and A340-600. The A340-600 was the largest-capacity member of the Airbus A340 Family, which would become the longest-range commercial airliner until Boeing 777-200LR appeared on the stage in 2005. Virgin Atlantic announced it will become the worldwide launch customer for the new A340-600 in August 1997.

As the competition continued between Airbus and Boeing, the U.S. planemaker came up with a new move in 1999. When Singapore Airlines ordered 17 A340-300s, all 17 of the A340-300s were purchased by Boeing in order to sell 10 new 777’s to the carrier in 1999. It would not be the last bad news for the A340. The Wall Street Journal reported that Thai Airways International halted its 17-hour non-stop route from Bangkok to New York to save fuel costs. Thai Airways flew the last flight on the route on July 1, 2008, and sold its four A340-500s.

Airbus A340

Last goodbyes to the A340

On November 10, 2011, Airbus announced that the production of A340 had ended. As for the reasons behind the decision, the company’s spokesperson told AeroTime: “Given the low orders placed for the aircraft type, Airbus decided that no new A340s would be built from November 2011. Airbus however still fully support the global A340 fleet as long as they are on operation”. When all airlines decide to retire their A340s, it will be the final ending for the aircraft.

There are other ideas on why Airbus stopped the production of A340. Aerospace engineer Thomas Stagliano shared his ideas with AeroTime: “Airbus was developing the A330 and the A340 at roughly the same time. The A340 with four engines and the A330 with two engines. First flights in the early 1990s. By then it became obvious that the airlines wanted long-range two-engine aircraft with the more modern larger and efficient and more reliable jet engines”.

Stagliano thinks that the competition between Boeing and Airbus hastened the process of ending the manufacturing of A340s.“Boeing came out with the 777 a year later in 1993 and that was a long-range two-engine airliner and that was the doom for the A340. Airbus needed to go back and make larger versions of the A330,” he explained.“The A340 ran its course quickly and then Airbus followed Boeing into composite aircraft with the A350 to counter the 787,” Stagliano added.

Recently, Virgin Atlantic announced that the company will phase out its last remaining Airbus A340-600s at the end of 2019 as it announces new order for 14 A330neos. By that time, 131 A340-500/600s were made, of which 123 remain in operation (as of July 30, 2019, including Virgin Atlantic’s six), according to Airbus’ Orders and Deliveries file. The largest operators of the type remain Lufthansa and Iberia (both airlines have 17 A340s in their fleets).

Source: https://bit.ly/2OXf9Vv

Image: Airbus