A new approach

“It provides us better technology for to allow us to have better navigation performance, allowing us to reliably and confidently know that our aircraft are on track and then allow our crews to descend to lower minimas, and with that have a little more schedule integrity in terms of our ability to get in and out and the like,” said Jetstar’s engineering project manager for RNP, David Lau.

For the carrier, implementing RNP originally started in June 2008 when it commenced trials at Brisbane and the Gold Coast as part of its original plan to roll it out in Australia. This saw it restricted to conducting RNP operations during day visual conditions as a result of some systems issues encountered on the A320s.

Another challenge was a delay from Airbus in gaining certification for its ‘Step Three’ RNP suite for the A320, which included a software upgrade to the aircraft’s flight management system to enable it to undertake RNP-Authorisation Required (RNP-AR) operations.

“Because the Airbus aircraft are all fly-by-wire they just need to go through very robust testing, so they completed about 20,000 hours of testing with three operators around the world with this software on board, and then they’ve got to demonstrate the accuracy of the system in non-normal situations,” said Lau.

While the issue was put on the backburner for some months, the start of domestic New Zealand services in June last year gave the airline greater impetus to pursue adopting RNP. In particular, there was clear benefit for its operations into Queenstown, a port where Qantas and Air New Zealand have used RNP to make approaches during inclement weather for a number of years.

“About mid June last year when we commenced operations to Queenstown when the airline quickly realised that RNP offered a lot of benefits at an airport that has high terrain and a lot of inclement weather. That really became the higher priority – to introduce RNP into Queenstown,” project pilot Nick Findlay told Australian Aviation.

As the services started at the beginning of winter, the airline soon found out the disadvantages of not preparing RNP prior to the start of its flights into Queenstown, with a number of flights forced to divert or be cancelled due to the weather. That had a major knock-on effect on its early New Zealand services, and contributed to the initial poor publicity it received.

Those incidents were seized upon by competitor Air New Zealand, which in some cases was able to make it in and out of Queenstown with its fleet of RNP equipped aircraft while Jetstar was forced to cancel or divert some of its services.

As such, CEO Bruce Buchanan has made getting RNP operations in time for the current winter at Queenstown a priority. “Our focus this year is really to get our domestic Queenstown operations to the level of reliability that RNP will give us and that will bring it in line with the rest of the network, and then we’ll look to expand operations as we move into next year,” he told Australian Aviation.

He explains that in the Queenstown context, RNP delivers much for the relatively small outlay. “The cost benefit analysis in Queenstown is very straightforward. It’s about lowering your diversion rate. Especially in the winter months you can lower your diversion rates by about 90 per cent,” he said.

Jetstar’s program involves the latest standard of RNP, known as Authorisation Required (RNP-AR), which utilises Airbus’s latest Step Three technology to determine the aircraft’s position and altitude. Compared to RNP 0.3 which is already being used by other carriers, RNP-AR incorporates additional navigational accuracy, integrity and functional capabilities.

Jetstar’s implementation of RNP-AR is taking place in three phases, with major consultation with CASA, the New Zealand Civil Aviation Authority, RNP design company Naverus and Airbus. The project is also utilising a number of staff across the organisation, while the company has also borrowed heavily from the RNP experience gained from Qantas, which first introduced RNP operations in 2004.

The first phase of the new RNP-AR project started in March. In this phase, the airline conducted 30 RNP operations at Queenstown and the Gold Coast during day visual conditions during March, after which it conducted a review of the data in conjunction with CASA.
At the time Australian Aviation visited Jetstar’s Melbourne headquarters in early April, indications were that the first phase of the trial had gone well, particularly at the more challenging airport at Queenstown. “We’ve got two flights a day [into Queenstown], and we’re probably only getting one in on RNP and that’s based around weather, aircraft availability and crew availability,” said Lau.

Following that review, the airline was expecting in early June to start on the second phase of its project, which will see it conduct 60 approaches and departures in instrument conditions ahead of another review gate. From there, the airline expects to be able to implement full RNP 0.3 procedures from June, just in time for the winter where the full capabilities of RNP are expected to be put to good use, ahead of further rollouts at other airports.

The wider rollout will also include a staged approach to take full advantages of the RNP-AR standard, which will allow it to operate down to RNP 0.2, which utilises greater precision. This will decrease the minimas required to operate RNP approaches further, and ensures that most approaches in all but the worst weather should be possible. It is expected that this will take place during 2011 in a phased approach.

As well as the operational benefits of RNP, Buchanan also points out that the greater reliability it offers could mean opening up new commercial opportunities, such as direct services from Australia to Queenstown. “Trans-Tasman flying is one of the things we’re evaluating, and it’s one of the things we’re looking at doing once we get our RNP capability up,” he said.

“There is a bigger business case for RNP as well which is linked to new navigation technology that will provide not only greater reliability in difficult situations, but also provides shorter flight times through shorter flight time through more efficient flight paths,” he said. “It also provides greater reduced fuel burn and greater reliability to get into a whole raft of different situations and destinations.”

“One of the benefits using RNP technology is that you can get shorter approach paths, so you get track mile savings,” added Lau. “They’re talking about up in Brisbane and Coolangatta you can save about 16 miles coming in on a curved approach.”

While that may not mean much on a single flight, for ports such as the Gold Coast where Jetstar has a high frequency of operations, the fuel burn and emissions savings can be significant. Airservices estimated that the use of RNP at Brisbane Airport could save up to 189 tonnes of carbon emissions each year.

From a pilots’ perspective is an increase in the safety of operations as Findlay explains. “For an RNP-AR departure out of say Queenstown, if you lose an engine on departure and you go IMC, you follow the engine out procedure which is all published. You don’t have to disconnect the autopilot and do anything radical, and all the performance is calculated,” he said.

There are also performance benefits of the technology. “The other benefit is on departure you can design an RNP departure that stays away from hills and you can potentially increase your maximum takeoff weight, reduce the thrust required and carry more payload,” said Findlay.

As RNP uses satellite rather than ground based aids that the procedures can be used if other aids there are also benefits if a ground based navigation aid, such as an ILS, becomes unserviceable. As an example of that, during July the ILS at Cairns Airport broke down one day, forcing a number of aircraft to divert elsewhere, while Qantas was able to use RNP equipped 737-800 services.

Training

With new technology being implemented, training pilots to operate RNP-AR approaches and departures has been a major project in its own right.

The majority of pilot training for RNP is being conducted by Jetstar pilots at the Ansett Simulator Centre in Melbourne on board its A320 simulator. However as the simulator has not been set up for training to Airbus’s Step 3 standard some differences training also has to be carried out, albeit very minor.

As of early April, the airline had 22 pilots in a control group trained for RNP-AR operations. Those pilots are primarily involved in operating RNP flights into and out of Queenstown as part of the first and second phases of the program.

Findlay explains what the training for those pilots has involved. “The training for a basic pilot in Jetstar endorsed on type would have to go through initial RNP training, which is not Queenstown specific. That training would be a half day ground school. Then there would be a four hour sim session for two pilots, and that would be at say the Gold Coast where they practice normal and non normal RNP procedures. Following that, they are able to go and do an RNP approach and departure in VMC conditions.

“They then go back into the simulator for a four hour session with two pilots, and they go through Queenstown procedures – all the approaches and departures, non-normals etc in varying weather conditions.”

The pilots who have received the sim training must then undertake line training, on a flight into Queenstown where they are supervised and assessed as being proficient in RNP-AR operations.

While currently focused on training the pilots operating into Queenstown on RNP, Jetstar is aiming to qualify all of its A320 pilots to conduct RNP operations as it rolls it out across the ports in Australasia. This will be done through extending the current xis monthly sim check cycle by one day to include an added simulator session.

Buchanan adds that the training currently being done for RNP has also been expanded to take in other skills which are aimed at increasing the airline’s ability to serve airports during different weather conditions. “We’re taking advantage of the training that we’re doing for RNP to also include low visibility training, which means you can land in much more challenging weather conditions at places like Auckland and Christchurch.

“So the benefits are not isolated to Queenstown, there’s also other benefits that we’ll see very quickly in the rest of the New Zealand ports as well.”

Australian rollout

With Qantas one of the earlier adopters in the world of RNP and Airservices Australia providing increasing means to use it at a number of airports, Jetstar has made it clear that it intends to roll out RNP-AR across its Australian network.

Initially, this will be on the A320 fleet which will receive the necessary upgrades over the next year, while all future deliveries have been specified with the necessary equipment to conduct RNP operations. The airline also has plans to roll out RNP across its A330 fleet in the future.

So far, the airline has built up experience using RNP approaches and departures at Brisbane and the Gold Coast. The latter airport, which can be subject to low cloud at times, is important to Jetstar due to the number of flights it operates, and the potential savings from having fewer disruptions.

Aiding this rollout is the commitment from Airservices Australia to roll out common-use RNP procedures at a number of airports around Australia, which Jetstar is planning to take advantage of. “They’ve actually contracted Naverus to do chart designs there they will have Sydney, Melbourne, Brisbane and Adelaide rolling out this year, and we’ll start piggy-backing off those when they start rolling out,” said Lau.

As part of that, Jetstar is trying to push for some of the smaller airports to also be included in the Airservices program due to the benefits. “We would see a lot of benefit in places like Maroochydore and Hamilton Island, but that’s not on their early radar,” said Lau. “You get cloudbase and the like, so the greater accuracy of your flightpath , you can get lower decision altitudes.”

For an airline like Jetstar which operates on tight turnaround times, being able to get into some of those ports can potentially save the whole network from experiencing a disruption.

Aside from its own benefits, the airline is also keen to push the use of RNP in Australia up for traffic reasons. “With all the aircraft that are doing an ILS approach, to have one aircraft come in and do an RNP approach does upset the flow a bit, so the more that RNP is rolled out, there is greater argument to fit the RNP aircraft into the flow,” said Findlay.

As such, there is some push from Qantas for Jetstar to continue its ramp up of RNP, in order to push the industry towards greater adoption of the technology, with the associated operational and economic benefits.

Overall, while the RNP project reflects a major undertaking for an airline like Jetstar, the benefits are expected to significantly outweigh the costs and ultimately allow the airline to deliver better services both in New Zealand and Australia.