This month EBAN magazine takes a look at the AW139, a twin-engine helicopter with one of the largest cabins in the intermediate class. Its two Pratt & Whitney Canada PT6C-67C engines support a maximum take off weight of between 6,400 and 6,888 kg with one or two pilots and up to 15 passengers.

Since type certification in 2003, more than 960 units have been sold to 240 customers in at least 70 countries, and more than 830 units are still in service worldwide. The new generation AW139 is known for favourable performance, reliability, safety, versatility and cabin space. It has one engine inoperative (OEI) capabilities, even in hot and high operating conditions, and its advan-ced integrated cockpit minimises pilot workload.

Designed to meet rigorous standards

The AW139 belongs to the Leonardo-Finmeccanica helicopter division family of products along with the AW169 and AW189. The family's models share many component parts and the same approach to maintenance and training, which translates into significant advantages in terms of operational efficiency and a reduction in life costs for users and mixed fleet operators. The cabin is spacious, comfortable and quiet, with energy-absorbing landing gear, fuselage and seats all designed to meet JAR/FAR 29 standards. It has a cruise speed of 165 kts and its large display avionics work together with the four-axis digital autopilot, with auto hover and full digital electronic engine control (FADEC), to minimise pilot workload.

With what Leonardo claims is the highest power to weight ratio in its category, it can accomplish vertical take off and landing in confined areas and on uneven terrain, and is one of the only helicopters in its class to fully satisfy the latest FAR29 and AIROPS regulations which incorporate crashworthiness and survivability features. In medevac configuration it can accommodate between two to four stretchers with up to five seats, and the large sliding doors provide unobstructed access to the flat-floor cabin for easy loading and unloading of patients on the ground and during hoisting operations.

The AW139 can achieve a range of more than 675 nm, with endurance of up to six hours for rapid deployment of personnel in police and security operations. It has a full ice protection system (FIPS) for flying in known ice conditions and has optional self sealing fuel tanks too. EBAN has spoken to operators of the helicopter in EMEA to paint a portrait of Leonardo's flying machine.

Going offshore

The first AW139 was delivered in 2003, and since then it has undergone a number of design evolutions. “The cost to maintain it is no different to any of its rivals,” says Mike Gislam, base manager at Norwich, UK, for the Belgium-headquartered Noordzee Helikopters Vlaanderen (NHV). “It has high payload capability and its performance is very good, which makes it particularly suitable for the company's activity in the oil and gas and renewables markets.”

NHV's core business started in Belgium with maritime support for wind farms. It is seeing an increase in activity from renewables due to the development of offshore farms, but at the moment its primary business is in oil and gas. The company is active in all oil and gas producing countries in the North Sea region, as well as having a strong presence in west Africa.

“We operate four AW139s at NHV,” says Gislam. “One is based at Norwich and the others are all based in Nigeria.” Other aircraft can suffer when the mercury rises, but he says: “We have found that the 139 copes well. Obviously it still has its limits and the heat does start to affect it at some stage, but the higher payload means its tolerance is greater than that of some other aircraft.”

NHV's use of its AW139s is mainly customer driven. “Some customers will ask us to advise them what the best aircraft choice is, while others say that they would like a particular aircraft and we then indicate whether or not we are interested in bidding for that work with that particular type of airframe. We also have the EC155 in Norwich so will have to see how things progress. But as a whole the aircraft choice is dictated by the customers,” says Gislam.

The Norwich-based AW139 is popular for offshore missions to the southern North Sea because of the distance and range it covers. NHV's is the very latest high spec model and was delivered in September 2015; it has TCAS II. “Ours was originally going to be a search and rescue (SAR) machine, but when we pulled it off the production line it was converted to oil and gas operations. However, we kept all the provision for winch capabilities on the aircraft.

“I can't really name any short-comings on the 139. We just have to ensure that we keep reacting to the changes that are coming in, just like any operator does.”

Fine tuning for safety in operation

Bel Air Aviation is the only Danish owned offshore helicopter company. Its main base is at Esbjerg airport and its fleet comprises three AW139s that sit alongside three AW189s. Both types are used for North Sea offshore missions to oil and gas stations and to wind farms. “The 139 is a bit smaller and is configured for 12 passengers while the 189 is configured for 16,” says MD Susanne Hessellund. “So the biggest difference between the two from the customer's point of view is the availability of seats on each flight.” At the moment the company is performing crew changes but it is going into the winching and hoisting market at some point in the next six months.

“The AW139 is the best helicopter I've ever flown,” says Hessellund. “It is very powerful and performance-wise it is at the top of its class. We are very happy with our rotorcraft.” She describes it as a workhorse, and was so pleased with its performance that she went on to take delivery of two larger 189s and order a third in 2014.

For Bel Air, the best attribute of the 139 is its safety in operation. The company decided to opt for 139s as opposed to other medium weight helicopters due to its payload and certification. “We knew what the Class I performance would be in Europe and the North Sea a few years after we took delivery of the first one in 2009,” says Hessellund. “We had to go into the market with a brand new helicopter, to stay ahead of our competitors.” Class I covers helicopter performance so that, in case of critical power-unit failure, the aircraft is able to either land on the rejected take off area or safely continue its flight to an appropriate landing area, depending on when the failure occurs.

Bel Air is an EASA Part 145 certified AgustaWestland service centre with approval to carry out continuing airworthiness on both its own and third party helicopters. The company set up a working group with Leonardo in order to save kilos on the AW139, eventually saving between 160 and 180 kg. “This was a great outcome,” Hessellund adds. “I don't see many areas for improvement on the aircraft because as time has gone on and the aircraft has developed, Leonardo has made improvements along the way. It will be nice to have an extra 200 kg on the new aircraft and we still have the opportunity to modify the current design further.”

As Bel Air regularly flies 12 passengers on trips of 230 miles, the weight adjustment suits the operation well. “I flew some of the earlier variants of the 139 and there is no doubt that the variant that has the longer nose led to a big improvement in the centre of gravity,” says Hessellund. “The avionics were then fitted to the front instead of the back, which was another improvement, and the centre of gravity is not as sensitive now as it was in the first versions.

“If we could go back and start all over again, we would still choose the AW139 and AW189,” she concludes.

From game to grouse

“We only have one AW139,” says Johnny Laing, operations manager at South African operator Fireblade. “It is mostly employed for VIP corporate travel; 85 to 90 per cent of the time it is used for the principal, the owner, but we do a bit of VIP charter with it as well.”

The owner is responsible for vast game areas, home to a lot of animals, and the company carries out a game census every year using the helicopter. “We have four counters and two computer operators, and we fly specific routes over the farm to count the animals.”

Interestingly, the livery of the Fireblade machine (see picture, page 12) depicts rock art and engravings from Zimbabwe, the Kalahari and Namibia. These reflect a whole host of early beliefs about the origins of life and connections between people, animals and plants. In these myths, trees have particular significance and there are stories of hunters who become part of their bark so as to merge into the landscape and become invisible during the hunt. Trees are often seen growing out of termite heaps which are symbolically generative and nurturing.

As well as working on game reserves, the AW139 is flown each year from Johannesburg all the way up through Africa and Europe to London, from where the passengers travel on to Scotland to spend the last two weeks of August shooting grouse. “It is a nice big helicopter, very reliable, and spacious inside too,” says Laing.

Johannesburg, where Fireblade is based, is 5,500 ft above sea level and the summers can get very hot. The aircraft has good hot and high performance, and the current rotorcraft is the second AW139 that the owner has had. “He had the first one from 2006 to 2012, and this one is coming up to three-and-a-half years now. He is completely satisfied with the aircraft on all fronts and doesn't see any reason to change it,” Laing says. It has upgraded avionics, the Honeywell Epic system, along with four-axis autopilot and all the necessary equipment for IFR. “Put simply, it is a nice aircraft,” he adds. “There is a renewal cycle every five to seven years, so after this time the owner will more than likely upgrade to a newer model. This way you keep close to the warranty and it doesn't go out of cycle.”

Fireblade also manages an Agusta 119, a small single which it uses for infrequent charter. “In the mining and other resources environment, most companies prefer to use twin engine rotorcraft. Before the 119 the owner had a Dauphin and an EC155, but the AW139 is a much better performer when it comes to power, especially in the hot and high Johannesburg area,” he continues. It carries a good amount of payload but one of its biggest advantages is that it offers a nearly four-hour range with extended fuel tanks, so it is possible to fly close to 420 nm before refuelling with full crew and another four passengers.

The 139 has only 15 per cent availability for charter but Laing believes that if it were more often available there would certainly be more work for it. “Because it is quite big, it does occupy a certain niche market. In South Africa there is not tremendous demand for this sort of thing from individuals, it is mainly corporate, resources companies who charter from us.”

Laing has flown French helicopters for most of his career but he has been flying the AW139 since 2006. “I have to say it is such a great machine, ticking the vast majority of the boxes,” he states. “It is very dependable and the engines are great. We are very happy with the product and we are fortunate that we have our in-house maintenance facilities, including factory-trained engineers, working on the machine.”

Hot and high stalwart

Earlier this year Leonardo-Finmeccanica celebrated the AW139's outstanding hot and high altitude performance and mission capabilities during trials in Pakistan which it reached on a ferry flight from Italy. The trials were conducted in the central desert area of Multan where temperatures touched 49°C, and in the northern areas of the Karakoram mountain range. The helicopter was still able to take off at its MTOW.

The desert flights included demonstrations of tactical low level flight capabilities and the ability to shut down and restart engines in just one minute. High altitude perfor-mance flights included take-offs and landings on unprepared surfaces at 16,300 feet density altitude and flights at 20,000 ft pressure altitude. The most demanding missions in terms of altitude and temperature were all performed with at least eight passengers and two pilots on board, in a fully mission equipped configuration including a passenger transport layout with up to 12 seats, air conditioning, a comprehensive avionic package encompassing TCAS II, HF radio plus rescue hoist and cargo hook provisions. Also included was fuel for more than one hour of flight plus required reserves. “The aircraft demonstrated significant power index margins in the most demanding conditions, highlighting its unrivalled perfor-mance and handling capabilities in an extremely challenging environment,” says a spokesman for Leonardo-Finmeccanica.

Following the testing the government of Pakistan signed a contract for an undisclosed number of AW139s for transport and EMS missions. Pakistan is one of several nations that are operating the 139s for a range of government roles, along with Italy, Ireland, the UAE, Qatar and Thailand.

A consistent performer designed for crew transfer

German operator HeliService International has an established core competence in the offshore transportation of personnel, injured personnel and cargo to and from wind farms, research and construction vessels. It is currently operating three AW139s, all equipped with a double hoist, and has just taken delivery of its first AW169, with a second due at the beginning of 2017. MD Eberhard Herr says: “We are not replacing the 139s, we are just adding additional aircraft to the fleet. The 169 will be used on hoist operations within the wind turbine industry, deploying service technicians to wind turbines, whereas the 139 is generally used for crew transfers. So the two aircraft types perform different functions.” On average the 139s fly between 800 and 900 hours a year.

Harald Heimerdinger, HeliService flight operations manager, has flown around 1,000 hours in the type so far, with an average flight range of 80 to 100 nm. “It has good passenger comfort and a lot of safety features,” he says. “For the ranges that we fly and the number of passengers we transport, between 10 to 12 at a time, it seems to be the optimum aircraft for a crew transfer. If the aircraft had more seats it would be too expensive for the customer, and if the ranges were smaller then it would be too big.”

“It is no secret that it has been a hot selling aircraft over the last ten years,” he adds. “There is almost no competition for it.” Its size enables it to transport up to 15 passengers to offshore rigs approximately 100 nm out. “If you wanted to go further out you would have to get a bigger aircraft like the S-92 or the Super Puma. But for the ranges we use here in Germany for the wind industry, the AW139 is perfect.”

Heimerdinger is very happy with the avionics suite. It allows him to fly for a multi-crew operation and has the most modern GPS approach capability, the localiser performance with vertical guidance (LPV), while the autopilot gives a smooth ride for the passengers. In terms of upgrades he says he would like to see the usual stuff that pilots wish for, to make it lighter and make it faster with less vibration. “Of course, you can't have it all. But over the years, it is nice to see that the airframe has become a lot lighter.” Between the first and last 139s delivered to HeliService, there is almost 200 kg of empty weight difference, and there are only a couple of years between them. As technology advances, so the electrical and avionic components become smaller and lighter, and the airframe benefits from that weight loss.

Along with the drop in the gross weight, enhanced autopilot features have been introduced. Phase seven saw LPV capability for approaches, and Heimerdinger hopes that in the future Leonardo continues to improve the autopilot features: “As with all the advancements that have been made with the AW189 and AW169, I hope these find their way onto the 139 in due course.”

Good serviceability

At the moment the three 139s cover the bulk of the HeliService workload and the availability of the aircraft is good. “It's not a question of getting another just in case one breaks down,” he says, “because the 139's serviceability is really good. If I compare it to older models like the Sikorsky 76, the Sikorsky has a 100 hour inspection where it's out of service for a week. The 139 is only out for one day.” Maintenance times have consistently shortened over time and this makes a noticeable impact on dispatch reliability.

The Super Puma's super sub

With the grounding of the L2 Super Puma type following an accident in April 2016 when an H225 ferrying workers from a Norwegian oil platform crashed into the North Sea, Babcock's SAR pilots were retrained on the AW139. Twelve seasoned SAR pilots, who had been flying the L2 for about a decade, have now finished the conversion course, and Mike Deakin, SAR manager for the company, is mid-way through doing the same.

“With the grounding of the L2, we were trying to choose an aircraft that was fit for purpose and available to us,” he says. Babcock missions are maritime SAR combined with medevac, which involves flying offshore to oil rigs to pick up people who have suffered heart attacks, strokes and traumas. “Probably 95 per cent of our role is offshore medevac, and then there is a five per cent search and rescue element in the oil and gas sector,” he adds. Where people on supply vessels become sick they will be winched out on a stretcher, as will those who have fallen overboard. “We also help with the local fishing industry, where we are picking up people off small fishing boats,” he adds.

The AW139 is well suited for these sorts of missions. Although a medium aircraft, it has space in the cabin to cope with picking up a large number of people out the water. It is also fast, and speed makes a huge difference when picking up someone requiring urgent medical attention. “It may only be 10 kts faster than another aircraft, but if you are dealing with illness, or people in the water, then those five or 10 minutes that we might gain going offshore make all the difference. For a stroke victim for example, picking them up and getting them to hospital in good time means they are more likely to make a full recovery, whereas a delay of, say, ten minutes could leave them with life-changing injuries,” he says.

Replacing FLIR with handheld goggles

Babcock's SAR AW139 lacks the forward looking infrared camera (FLIR) search tool of the Super Puma, but next year sees the introduction of hand held FLIR goggles, which its pilots prefer when searching in a very small area. “If we are tracking to a beacon of someone who is in the water, someone who has fallen overboard, we first track them with the homer and find them in the water. Then we can use our handheld system rather than the FLIR pod that we used to have,” he says.

Neither does the new aircraft have a winch camera built into it, so Babcock's pilots are already going down the route of putting GoPro cameras on their winch ops. “This gives us a much better view of what's going on outside the aircraft, on the deck and so on, while we are winching.”

But the great thing about the AW139 is the full icing protection system (FIPS). “With this, the AW139 can fly in more or less any weather except freezing rain, which no one is going to fly in anyway,” Deakin adds. “Nothing else will stop us. And given the winter weather in the North Sea, having a 139 with FIPS really makes it a very capable aircraft.”

Babcock has carried out a number of cabin modifications, including a cabin extension that is used on almost all SAR aircraft; a tunnel leading from the cabin to the baggage hold. The second biggest modification is a C-Tray that keeps the cabin protected from infection by stopping any blood staying in the aircraft. Otherwise much of the outfitting is already standard, such as the Goodrich hoists, the SAR autopilot modes and the auto hover function. These allow automatic transition down and up in instrument meteorological conditions (IMC), that is to say in bad weather. “All of these features are standard across SAR 139 aircraft, but they are very much cutting-edge compared to what we had on the Puma. That was 1990s technology, whereas this is real 21st century technology,” says Deakin.

“From a pilot's perspective, the automatic transition up and down is particularly impressive because it frees up his/her own capacity,” he reports. “On a typical dark and stormy night such as is common on the North Sea, transitioning down to a 50 foot hover is a relatively pleasant experience because the aircraft does all the hard work, leaving the pilot to monitor the systems and make sure the craft is performing safely.”

Babcock's Aberdeen SAR oper-ations team have a primary and a backup aircraft which are both kitted out to exactly the same specification, and are both available at the same time. “We do our maintenance at the weekends, when we might take our backup aircraft offline, but we always make sure it is recoverable within a sensible period of time,” he says. The team has only been operating the AW139 for a few months but is very impressed with the type's reliability: “And not only reliability. If we do go AOG for some parts, or we have technical issues, the manufacturer gives us really good support. Leonardo-Finmeccanica is aware of the importance of our project and has engaged with us at the highest level about this particular operation. They have gone out of their way to support us.”

Designed around the pilot's workload

The transition to the AW139, with the necessary pilot retraining and modifications, was launched as a 12-month project, but with support from Leonardo, this has been compressed down to six months. “From my point of view as a pilot, the 139 is really designed around pilots and the workload pilots have. The visibility we have from the cockpit is fantastic, the ergonomics of the cockpit and the way it is laid out are ideal for my role, and it really makes it a lot easier for me that everything is where I need it.”

It is also very quick to start. If the pilot is trying to get away to an SAR tasking on a 15-minute readiness, then the way the aircraft starts is good for purpose.

In March of this year, Stuttgart-headquartered DC Aviation expanded its private jet operating licence with the takeover of BHS Helicopters to include the commercial use of helicopters. DC Aviation Switzerland, originally called Jet Link and acquired by DC Aviation in the summer, has now added an AW139 for operations which include alpine flying.

Michael Kuhn, DC Aviation's CEO, says: “This valuable addition is the direct result of our customers' steadily growing interest and trust in our long-term experience in the management of private and commercial aircraft. We see this as an acknowledgement of our expertise and capability in providing our VIP customers with services of unsurpassed quality at maximum safety.”

High security

“From my point of view, as general officer commanding the Irish Air Corps, the AW139 has been a great success,” says Brigadier General Paul Fry. “It has brought our technology base right up to date, expanded our capabilities and importantly has added night operations to our portfolio, giving us much improved security coverage across the region if and when it is needed.” Being more or less a launch customer for the type means there have been teething problems, but these have been overcome with Leonardo's assistance and, according to Fry, their product support quality remains very good.

Thus, we have seen that the AW139 is well-suited to a wide range of roles. Being a large and spacious machine, group transport – especially for oil and gas workers – is where it shines. Yet its stability, start speed and resilience in almost all conditions make it just as adept in a SAR role. In the case of Firebalde and DC Aviation, the 139 is also a very desirable private people carrier, and it seems clear that customer devotion to the type will increase as the latest AW169 and AW189 technology finds its way onto the smaller variant.