In much of the world, all-weather commercial air transport operations using single-engined turbine aircraft such as the Pilatus PC-12, Socata TBM series or Cessna Caravan have been permitted for years. The notable exception was Europe. Then, some 18 months ago, safety regulator EASA looked ready to approve a painstakingly devised set of provisions for allowing commercial single-engined turbine (SET) passenger operations in instrument meteorological conditions (IMC).

At that time, manufacturers of fast turbine singles could have been forgiven for predicting a sales bonanza. And, true to its word, on 1 March last year EASA supplied the expected approvals to usher in SET-IMC operations.

But uptake by operators of this much-heralded opportunity has been slow and that sales surge remains unrealised. Why? Turbine singles have gone on selling at a healthy rate even in Europe, but most of them go to private buyers who do not require a commercial air operator certificate.

Asked whether EASA's SET-IMC permission has changed the marketplace for its PC-12, Pilatus has this to say: "We have been approached by many existing commercial operators after EASA’s approval of Commercial SET-IMC ops. In addition, we were also contacted by new operators which have to get their AOC first. There is also interest by some private owners who see an opportunity to charter out their aeroplane. So, in summary, the new rules are definitively positive for the Pilatus PC-12. They are certainly a contributing factor to our solid backlog in Europe."

Cessna technically has a pressurised single turboprop in the race – its Caravan is rather slow and is not pressurised, but its in-development Denali has performance that approaches that of the Socata TBM series.

Preparing it for the European marketplace, Cessna says: "The Cessna Denali aircraft and GE Catalyst engine are being designed to comply with the EASA CAT SET-IMC requirements. We are actively working with EASA and together have defined a clear path for the Cessna Denali to achieve compliance with the regulation." Once technical compliance is achieved, some time will need to pass to prove reliability compliance figures. A first prototype is in assembly at Cessna's Wichita headquarters, with first flight expected by the end of the year.


Edwin Brenninkmeyer, chief executive of Biggin Hill, UK-based Oriens Aviation, a PC-12 dealer that manages 12 of the type at the moment, says the problem in the UK is the expense of being the first in any given country to upgrade to SET-IMC standards. The first to do it has to write the books and prove the case to the national aviation authority. Once somebody does it, says Brenninkmeyer, the task becomes progressively cheaper, encouraging more to take that step.

Europe's operating expert on the subject of SET-IMC, particularly using PC-12s, is Matti Auterinen, chairman of Vantaa, Finland-based Hendell Aviation. Since 2008, his company has had an AOC as an EU commercial carrier, and was one of the first to be given SET-IMC exemptions for particular services before the EASA approval became effective.

Auterinen has been working with EASA for years to define the challenges of SET-IMC and find ways to overcome them. For that reason he has unparalleled experience in drawing up PC-12-specific operating procedures for approval by the European agency, and is highly sought after by operators who want to set up similar operations.

Auterinen explains what he believes the problem is in parts of Europe – including the UK – at present: "I think the challenge is more about the complexity of running a modern small airline in the EASA environment – all the increasing requirements on management, the safety management system (SMS) and compliance – than about operating the single-engined aircraft itself.” He also points out that it would help operators if there was a PC-12 full-flight simulator located in Europe, but even Pilatus does not offer one.

Ian Austin, managing director of UK-based Jet Exchange, is fully rated as a PC-12 pilot and manages one of the type for a group of four co-owners. It is a busy aircraft by the standards of privately owned business types, working about 600h a year. He says he is planning to obtain an AOC as a PC-12 operator, has contracted Biggin Hill-based Total AOC to help him draw up the manuals and prepare to meet the management requirements, and is looking for another PC-12 with owners that want to offset their costs by working it harder under an AOC. He says he hears the point Auterinen makes about the lack of a PC-12 simulator in Europe, but says in fact, it can be cheaper to give pilots training time in the aircraft itself.

But there are indeed some PC-12 operators with a commercial AOC in Europe, Auterinen points out, because his organisation is the enabler for many of them: "The majority of our operation nowadays is managed from our Lausanne operations control. Our commercial sales department is also there. Our own business is expanding rapidly now, with a total of eight PC-12s being operated commercially. One is in Finland and seven are elsewhere in central Europe. This year we expect to operate a fleet of more than 10 aircraft under a commercial AOC. In total, our continuing airworthiness management (CAMO) business takes care of 13 aircraft."

Hendell, together with FLY 7 Executive Aviation, fully manage the PC-12s for their owners with full service on AOC, CAMO, operations, crewing and sales through the extensive sales network, as well as brokerage.

Auterinen calls the service "jet look-a-like" for the charter customers. He adds: "The model has been found very efficient by our customers." His ambitions go much higher, however – more in line with what the aircraft manufacturers might have begun dreaming about when EASA gave its SET-IMC permission.

Auterinen explains: "In the future we are aiming to command our own fleet for dedicated charter and scheduled routes, which we cannot disclose at this stage. However, the current model provides us with sustainable growth, and at the end we will have the strength to expand and design new business models, having already created a strong basis with a pool of pilots, a training model, etc.”

The Auterinen model looks like the future operators such as Jet Exchange dream of. Austin himself admits that one of the primary problems an operator faces is attracting qualified crew and, being able to keep them fully trained, and retain them on strength. Flying a PC-12 into demanding destinations, especially in IMC, is a job for a two-pilot crew and, he admits, most customers expect to see a full crew.

Austin says he is considering the possibility of offering a "cadet scheme", where brand-new pilots with a CPL/IR and multicrew co-operation course fly the PC-12's right hand seat for "not much money but excellent crew training". Flying a single-turboprop aircraft like a Cessna Caravan might have been seen as an entry-level job for a new pilot with a CPL/IR.


But EASA regulations acknowledge that the position of a commander flying a commercial SET-IMC flight demands much more than minimum commercial pilot licence experience in terms of total flying hours (minimum 700h), time in command (minimum 400h), and time flying under IFR (minimum 100h), so this is not an entry-level piloting job. For that reason, commanders will have to be attractively paid or there will be a supply problem. Then there is the expense of the specialist SET-IMC training, as Austin acknowledges.

Austin observes that PC-12s are expensive to buy, but with a full cabin, the fuel use per passenger compares with a family car, so operating costs are low, and training in the aircraft itself is relatively low cost, too. Hendell sends pilots to the USA for simulator training, because there are sufficient PC-12s there to make a simulator pay, enabling crews to practise exercises that would be too risky in the aircraft.

US-based training organisation FlightSafety International – which dedicates a great deal of its training capacity specifically for the business aviation industry – provides training for PC-12 pilots, with full-flight Level D qualified simulators for the PC-12NG, PC-12 Legacy and new PC-24 aircraft at its centre in Dallas, Texas.

Operators "from around the world", it notes, are taking advantage of these programmes, but at present it has no plans to place a PC-12 simulator in Europe. Meanwhile, Austin comments, UK operators can, if their training needs dictate, practice high altitude engine-out glide approaches in a PC-12 into fully capable but low-traffic airports such as Inverness in Scotland.

Although it is clear from Auterinen's experience that there are clients that do not shy away from machines with propellers, or with only a single engine, there are some who will not accept either. This factor adds to the business risk hurdles facing someone like Austin when considering investing in an AOC for even a sophisticated, pressurised single-turbine like the PC-12, with a large, comfortable cabin. But another advantage a turboprop can offer over a twinjet is better short take-off and landing performance, which opens up for access airfields jets could not use. He offers Courchevel in the French Alps as a typical example.

However, voicing his awareness of other hurdles to achieving a viable SET-IMC operation, Austin lists restricted airfield opening hours at the smaller aerodromes, fire/rescue cover, and airfield lighting as just some of the issues. For PC-12s operating at night it would be desirable to have more aerodromes that installed pilot-controlled airfield lighting, so the crew can switch on the runway lights when they are approaching the circuit. The future may hold other delights like remote tower operations to enable small airfields to provide a service out of hours, but nobody seems to be talking about that much yet.


To understand why winning an AOC for SET-IMC in Europe is not simple, it is worth reprising the European regulator’s demands. Previously, commercial SET passenger operations had been permitted in Europe, but only in daylight visual meteorological conditions (VMC). In addition, a few European carriers operating turbine singles in areas of relatively flat terrain and low population density were awarded SET-IMC exemptions for defined operations. It all boils down to the simple fact that if a single-engined aircraft suffers engine failure, the pilot's only option is to glide to a forced landing.

If this happens at night or in poor visibility, a forced landing in an aircraft without special equipment is likely to be fatal for the occupants and for anybody in the aircraft's path. In North America and Australasia, for example, population density is relatively low, but Europe has nearly four times the population density of the USA, and an even greater multiple compared with Canada or Australia, so the risk of a blind forced landing to the population on the ground – as well as the aircraft occupants – was judged unacceptable. This risk was seen as particularly significant in areas like England's southeast, with its many urban centres, and where even the countryside is well-populated.

The technical advances that have permitted EASA to approve SET-IMC in Europe’s airspace include increased engine reliability, boosted by engine/gearbox health monitoring systems. But no matter how low the probability of an engine failure, the aircraft and crew are required to be able to cope with it – and in IMC or at night. The factors that impressed EASA include the fact that a pressurised single like the TBM series or the PC-12 has a high cruising altitude, therefore a considerable glide distance, making diversion flight planning and risk management easier.

A much more powerful battery system to power full avionic capability during the descent, plus a powerful landing light to illuminate the final approach to a forced landing, are essential. Advanced avionics and flight management systems play a major part. For example, the Honeywell avionics suite in a SET-IMC-approved PC-12 can allow the pilot, in the event of engine failure, to select a diversion airport and runway in use within glide range, and the autopilot will fly the aircraft to arrive over the threshold at 50ft on its radar altimeter.

But the aircraft also has to be equipped with a crew that can manage such a descent, glide approach and landing, which is not a scenario that is part of the recurrent training for multi-engine airline pilots.