Air New Zealand says it expects about 9000 customers to be affected by global Rolls-Royce engine problems this week as it grapples with weight restrictions that are converting non-stop services into one-stop flights.

The New Zealand carrier said the engine problem was affecting two key United States routes — Los Angeles and Houston  —  as well as services operating to and from Japan’s Haneda airport and a limited number of trans-Tasman and Pacific Island flights.

WATCH: World’s scariest landing

All other services were operating as normal and the airline estimated the problem was likely to affect less than 3 percent of passengers traveling by Air New Zealand this week.

The FAA issued an airworthiness directive last week that lowered extended-range twin-engine operational standards (ETOPS) for Dreamliners fitted with Package C engines from 330 minutes to 140 minutes. ETOPS defines the maximum flying time the aircraft is allowed to be away from a suitable diversion airport.

READ: Airlines scramble to inspect CFM engines on some 737s

Rolls-Royce found that stage 2 blades in the intermediate pressure compressor have a resonant frequency that is excited by high airflow resulting from high thrust settings at certain temperature and altitude conditions. This can cause cumulative blade failure and an engine shutdown.

The FAA’s worry is that if one engine shut down, the remaining powerplant would operate at maximum continuous thrust for a prolonged period and create conditions that would increase the likelihood of the remaining engine failing. The problem is even more acute if the blades are already cracked.

The FAA’s AD came after European safety regulator EASA required inspections of the engines and Air New Zealand was forced to ground two of its Dreamliners.

Now the weight restrictions mean some AirNZ Boeing 787-9 Dreamliner flights to Asian destinations may need to make refueling stops.

Chief Operational integrity and standards officer David Morgan said that some flights may not be able to depart with the required fuel load, although this depended on en-route weather conditions.

Over the weekend, AirNZ 787-9 flights made fuel stops at Sydney, Cairns, Darwi, and Guam.

“Having the flexibility to make a short fuel stop means we are more likely to be able to take a full contingent of customers and cargo,’’ Morgan said. “The alternative would see us potentially having to disappoint significant numbers of customers by moving them to later flights.

“We are committed to doing everything possible to avoid this, particularly during this busy school holiday travel period.

“The fuel stops take around an hour to complete and passengers must remain on board.  Where possible the operating pilots will increase speed to make up time to achieve an arrival time at destination as close to schedule as possible.”

Customers who have a connecting flight booked on the same ticket, and who are likely to miss their connections would be rebooked on the next available connection.

Tensions have flared again between the Gulf States amid allegations Qatari fighter jets flew “perilously close” to an Emirati Airbus A320.

The UAE claimed the fighters flew came within 700 feet of the A320 as it traveled between Dammam in Saudi Arabia and  Abu Dhabi.

The Bahrain News Agency said the flight, identified as Etihad flight ETD88, met all requirements and the aircraft, identified Etihad Flight ETD88, was traveling at an altitude of 25,000 feet above the international waters within Bahrain Flight Information Region (FIR).

“The Qatari fighters flew too close to the UAE civilian aircraft, jeopardising its safety, which required the intervention of the air control in Bahrain to take the necessary procedures to maintain safety of aviation and the pilot of the plane to manoeuvre and lower it to an altitude of 24,600 feet in order to avoid the Qatari fighters,’’ the agency said.

UAE state news agency WAM said the UAE General Civil Aviation Authority described threats to civilian passengers as completely unacceptable and that it would file a case with the  International Civil Aviation Organization (ICAO).

“Qatari jets chased the UAE passenger plane and came close to it leaving just seconds before collision… a very dangerous and unsafe approach which endangered the lives of passengers,” WAM quoted a statement by the UAE General Civil Aviation Authority as saying.

The Bahrain Ministry of Foreign Affairs said on its website that it reserved the right to  take all measures with ICOA and other agencies “to preserve the safety and security of civil aviation and passengers against irresponsible and illegal Qatari practices.”

“The Airbus, arriving from Dammam airport to Abu Dhabi, was carrying dozens of passengers while flying over international waters on the international air corridor in the Bahrain flight information region, flying in a well-known track and fulfilling all necessary procedures,’’ the Ministry said.

“The Ministry reiterates that these provocative and repeated acts, which the State of Qatar bears responsibility for, represent a threat to passengers and endangers their lives. it also threatens the safety of civil aviation and is a serious violation of relevant international laws and conventions.”

The UAE and Qatar also clashed in January over the interception of civilian aircraft by Qatari fighters.

Relations between Qatar and its neighbours have been tense since Egypt, Bahrain, Saudi Arabia and the United Arab Emirates in 2017 severed diplomatic ties with Doha and imposed an economic blockade that included closing airspace.

READ: Qatar vows to expand network despite Middle East bans.

Air New Zealand has been forced to ground two of its Boeing 787 jets after safety checks revealed problems with some of the airline’s Rolls-Royce engines.

The New Zealand carrier faces further service disruptions and is investigating again chartering aircraft to compensate for the loss of the aircraft.

SEE Spectacular landing and take-off video

It is one of a number of airlines caught up in global problems affecting several hundred 787 engines which have prompted action by the US Federal Aviation Administration and European safety agency EASA.

The problems have caused several engine failures and “numerous” reports of engine inspections finding cracked blades resulting in unscheduled engine removals, according to the FAA.

Read: FAA moves on Roll-Royce Trent troubles.

Air New Zealand earlier this week rescheduled some services and announced a small number of cancellations as it performed checks required by EASA and Rolls-Royce on engine compressors in  Trent 1000 Package C engines.

“As a result of the checks, two Air New Zealand 787-9 Dreamliner aircraft will be temporarily removed from service while engines undergo maintenance work at a Rolls-Royce facility in Singapore,’’  the airline said.

“Around 340 engines globally are subject to the checks and this is placing very high demand on Rolls-Royce’s maintenance facility meaning it may take a number of months before Air New Zealand’s engine repair work can be completed.”

The airline said it would publish schedule changes in the coming days and it would communicate directly with affected customers and travel agents.

It said options to counter the loss of the aircraft would include re-introducing charter services operated European carrier Hi Fly next month.

Air NZ undertook the engine checks after problems with the Package C engines prompted EASA and Rolls to reduce the number landing and take-off cycles between inspections.

The FAA followed with an Airworthiness Directive reducing the maximum flying time affected 787s are allowed to be away from a suitable emergency airport from 330 minutes to 140 minutes.

The US regulator said it had been told by Boeing that Rolls-Royce had determined that intermediate pressure compressor stage 2 blades have a resonant frequency that was excited by airflow at high thrust settings under certain temperature and altitude conditions.

The vibration caused by this could result in cumulative fatigue damage that could cause blade failure and engine shutdown, it said.

Air New Zealand Chief operational integrity and standards officer David Morgan said the airline was fully compliant with the directives of EASA, the FAA and Rolls-Royce.

“Unfortunately this will mean disruption for our customers in the coming months as we adjust our schedule and fleet utilisation to accommodate these challenges and we thank our customers for their patience as we work through this,” Morgan said.

“Like Air New Zealand, aviation regulators prioritise safety over everything else and EASA and FAA have taken a very conservative approach in the checks and restrictions they’ve put in place around these engines.

“Customers travelling on our Dreamliner aircraft can be very confident in the integrity of the engines.”

The days of worrying whether you and your bags will end up at the same destination are receding with airlines set to introduce new technologies after again reducing the mishandled baggage rate in 2017.

The annual global survey by aviation technology company SITA shows the mishandled bag rate improved 2.8 percent in 2017 to 5.57 bags per 1000 passengers.

WATCH Spectacular Take-off and Landing Video 

The total number of mishandled bags was up 4.1 percent compared to 2016 but this was lower than the 7.1 percent rise in passenger numbers.

On a regional basis, the US mishandled baggage rate fell to an all-time low of 2.4 per 1000, despite operational challenges from hurricanes and Atlanta’s power outage.

The rate in the Asia-pacific rose 6 percent but was still significantly lower than the global average at 1.92 bags per 1000 passengers.

Europe continued to let the side down with an above-average 6.94 mishandled bags per 1000 passengers, although this was a significant improvement over 2016’s 8.06 per 1000.

The main reason for lost or delayed luggage remained mishandled transfers followed by failure to load bags in the first place. Ticketing errors, bag switches and security errors accounted for another 15 percent followed by airport, customs, weather and space or weight restrictions.

While the global year-on-year improvement was modest, it continued a trend that has seen the mishandled baggage rate fall by 70 percent since 2017 and SITA believes 2018 will be a watershed year.

Airlines have done a great deal of work on baggage tracking over the past decade. This not just a case of passenger satisfaction: lost or mishandled baggage costs airlines money and that added up to $US2.3 billion in 2017.

In 2007, 2.48 billion passengers were flying and airlines lost 46.9 million bags. More than 4 billion few in 2017 and it lost half that amount — 22.7 million bags.

Read American plans to expand the use of advanced baggage scanners.

This is set to improve as airlines adopt new baggage tracking technologies as part of an International Air Transport Association edict known as Resolution 753.

Resolution 753 requires end-to-end baggage tracking and will see passengers gaining greater insight into where their bags are in the labyrinthic baggage system.

“Over the last decade, we have seen significant improvements in bag management as airlines have taken advantage of technology,’’ SITA chief executive Barbara Dalibard said in releasing the latest report. “Now with IATA’s drive for 100 percent bag tracking, technology adoption will rise further.

“End-to-end tracking produces data which reveals where improvements can be made in operational processes.

“While we won’t see a sudden change in 2018, it is a real turning point for the industry as airlines begin to unlock the value of the tracking data for the 4.65 billion bags they carry.”

The SITA report cites a number of innovations adopted by airlines to improve the baggage service.

These include off-airport bag drops such as Virgin Australia’s pop-up check-in and bag drop service at cruise ports, conference venues and hotels.

Airlines and airports are also boosting the use of automation with almost nine out of 10 expected to provkid4e assisted bag-drop stations by 2020.

The report cites Cathay Pacific’s experience at London Gatwick where self-service check-in and bag drop has halved processing time to just under a minute.

Then there’s the Resolution 753 bag tracking requirement starting in June, 2018, for IATA member airlines.

“As airlines prepare for Resolution 753, there will be a rapid increase in those planning to provide bag tracking information to their passengers and staff,’’ the report said.

“At least seven out of ten airlines expect to be providing these services by 2020. Resolution 753 is also driving mobile services for mishandled baggage, with up to eight out of ten airlines implementing, or planning to implement, missing bag reporting and missing bag communications.”

The journey of feisty upstart Virgin America ends on April 24 as new owner Alaska Airlines retires the airline’s flight numbers and transfers all customer functions to its website.

Starting on April 25, every check-in will be performed by alaskaair.com as the bigger airline also takes overall customer service and mobile app functions.

The Virgin America brand will be removed from airports and all images and signs updated to the Alaska brand at 29 airports around the US and Mexico.

“Signs and screens will all change to Alaska branding at curbside locations, lobbies, ticket counters, gates and baggage areas,’’ the airline says on its website. “While there will be some Virgin America painted aircraft still flying for a period of time after April 25, tickets will be sold only under the Alaska name.”

The airline has already painted some Virgin America aircraft in its colors. It will start installing new interiors from the US autumn with work expected to be completed by 2019.

Read: Alaska, Qantas double codehare operations

Alaska bought Virgin America for $US2.6 billion in 2016  and the two carriers have been operating under one operating certificate since January. Obtaining the single certificate took 110 employees 70,000 hours as they analyzed more than 39,000 pages of material and instituted about 15000 changes to policies.

The merging of staff from the two airlines took another step forward the following month with a tentative merger agreement for the company’s 5400 flight attendants.

Virgin American was launched by billionaire Richard Branson on August 8, 2007, and delivered a breath of fresh air into the US domestic airline market.

It was a hit with travelers and won a slew of awards, including from AirlineRatings.

Alaska has used Virgin’s fleet of Airbus aircraft to drive into new markets and expand its network.

Read our ratings for Alaska Airlines.

Today, the combined airlines and their regional partners operate 1200 daily flights to more than 115 destinations and employ more than 23,000 people.

Separately, Alaska announced Thursday that it was joining other carriers in introducing new rules for emotional support animals for tickets purchased after May 1.

Passengers traveling with emotional support or psychiatric service animals must provide animal health and behavioral documents after this date, as well as a signed document from a medical doctor or mental health professional, at least 48 hours in advance of departure.

The change does not apply to the airline’s policy for traditional service animals such as guide dogs.

Engines similar to one involved in a deadly incident on a Southwest Airlines flight between New York and Dallas will be subject to a new regime of checks within weeks.

The US Federal Aviation Administration said Wednesday it would issue an airworthiness directive within the next two weeks requiring inspections of certain CM56-7B engines.

Engine maker CFM said after Tuesday’s shock engine failure that the CM56-7B had powered about 6700 planes worldwide since entering service in 1997 and had compiled “an outstanding safety and reliability record”.

WATCH Spectacular Landing and Take-off video

The FAA said the directive would require an ultrasonic inspection of fan blades when they reached a certain number of landings and take-off.

“Any blades that fail the inspection will have to be replaced,’’ it said without specifying the number of cycles or how many engines would be involved.

Southwest, which had a similar engine incident in 2016, had already announced an accelerated its fan blade inspection program and expected it to be completed within 30 days.

A 43-year-old mother of two was killed when she was partially sucked out of window that had been broken by shrapnel from the engine. Passengers managed to drag the woman back inside but she died of injuries.

The plane diverted to Philadelphia where it made an emergency landing.

Read: Fan blade missing in SouthWest Airlines engine involved in shock passenger death.

The AD comes after NTSB chairman Robert Sumwalt revealed that a fatigue crack believed to have initiated the engine failure was on the inside of the number 13 fan blade and not detectable by looking at the component from the outside.

Sumwalt said the blade separated in two places with the fatigue fracture at the hub holding all 24 blades and the second fracture halfway along.

“But it appears that the fatigue fracture was the initiating event which later caused that secondary failure,’’ he said.

The NTSB chief said investigators had the root of the blade, but not the rest of it,  and it was too early to tell whether it was a pre-existing anomaly such as a manufacturing fault.

Asked whether there was a broader flaw with  737 engines,  Sumwalt said investigators wanted to carefully understand what had happened at Southwest.

“As  I mentioned a few minutes ago I’m very concerned about this particular event,”’ he said. “To be able to extrapolate that to the entire fleet, I’m not willing to do that right now.

“We need to understand what happened here.’’

Sumwalt said that if the NTSB had the capability to issue urgent safety recommendations if it believed there was a deeper issue.

“We’re not doing that tonight because we don’t fully have all the facts surrounding this,’’ he said. “But I will say the CFM56 engine is a very widely used engine and it’s got a great record generally speaking.’’

Pieces of engine cowling — the exterior engine covering — have been found 65 miles north-west of Philadelphia and the NTSB is hopeful other parts may be found.

Sumwalt also revealed in his briefing the plane rolled sharply to the left after the trauma and reached a 41-degree bank angle but this was quickly corrected by the pilots.

He said there was “a fair amount of vibration’” during the 22 minutes between the initial event and touchdown at Philadelphia.

A  decision by the flight crew to land with a flaps setting at 5 because of concerns about aircraft controllability meant the aircraft touched down at about 165 knots (190mph) compared to a typical 737 approach speed of around 135 knots.

Among the many issues investigators are probing is how the window failed.

Although the assumption in new reports is that it was shattered by shrapnel, Sumwalt said no window materials had been found inside the aircraft.

Despite real progress in the last couple of decades in upgrading terminals and the airfield, getting to, through and around Los Angeles International Airport can still be a first class pain.

The epicenter of the problem is the closed-in, U-shaped configuration of LAX itself, a set-up that has flummoxed flyers for years.

Now comes word of some hope of untangling the ground transport mess. The Los Angeles City Council recently approved a $US4.9-billion plan to construct an Automated People Mover (APM) system, set to be up and running in 2023.

Read: New concourse aims to reduce gate wait at LAX.

LA Basin flyers have been clamoring for answers to the airport’s ground transport woes for years, even as the rest of the airport moved ahead with terminal and improvements.

Los Angeles Mayor Eric Garcetti says travelers “have been asking for reliable, convenient transportation to and from the terminals.”

AMP is the linchpin for an airport’s ground transport set-up that planners see encompassing a consolidated car rental facility and connection to LA Metro’s regional transport system.

Plans call for LA Metro to pick up and drop off flyers outside the terminal loop. Officials say that should cut congestion as well as emissions.

Bombardier Transportation will build the AMP. It’s got the experience and knowhow. It’s been involved in similar projects in Dubai, London Heathrow and Munich, among others.

Trains will arrive every couple of minutes. Doors will be wide to ease the burden of lugging luggage around.

Los Angeles World Airports, which runs LAX, says the system will be able to handle some 10,000 passengers per hour. That adds up to 87.7-million riders each year.

LAX has racked up tremendous growth over the past few years. The planet’s fifth-busiest airport—second-busiest in the U.S.—fields 737 daily nonstop to 100 domestic cities a formidable 1,386 nonstops to 88 cities in 73 foreign countries.