Wings of Mercy

For reasons we shall examine in a moment, the next generation of RFDS aircraft is likely to see the King Air’s so far unique capabilities duplicated across the entire RFDS fleet.

The RFDS (Central Section), based in Adelaide, bought its first King Air in the late 1980s when the Royal Adelaide Hospital set up a Hyperbaric Unit to treat diving accidents. In order to carry an 800kg decompression chamber the RFDS needed a much larger aircraft than the existing Piper Navajo Chieftains operating in the air ambulance role from Adelaide. Super King Airs with the necessary internal space and cargo doors were starting to come on the market with low airframe and engine hours at affordable prices so the Service bought one of these in the United States. It was reregistered in Australia as VH-HEO.

Although the initial scheme to carry decompression chambers did not proceed, the RFDS (Central Section) recognised the value of a fast, roomy turboprop aircraft and made the most of this purchase. The Super King Air B200C made possible a quantum leap in the service the RFDS could provide to the outback: not only could it cover the ground faster,it had the potential to offer a far higher level of patient care than the smaller, slower and unpressurised Navajos and Chieftains then in service with the Central section.

It is worth reminding ourselves here that the Flying Doctor service is more than just an air ambulance. An RFDS aircraft is a flying treatment room in which qualified doctors and nurses can monitor patients whom they have already treated (and carry out a certain amount of further treatment) while en route from pickup point to hospital. The limits to the treatment which can be carried out in an aircraft, however, are set by such mundane things as cabin space and the availability of electrical power to run medical equipment, the provision of medical oxygen, and pressurisation. Which is why the King Air has proved to be such a success.

RFDS (Central Section) Chief Pilot Graeme Maughan was the first to convert to the new aircraft. “With a King Air and three Chieftains based here at Adelaide, a King Air and two Navajos at Port Augusta and another King Air and two Navajos at Alice Springs, nobody South Australia and the southern sector of the Northern Territory is now more than one and a half hours flying time from medical treatment or a hospital. In the King Air we can cover a 200nm sector in less than an hour, cruising quite happily at 24,000ft – well above the weather. The difference it makes to the patients’ comfort is enormous. ” VH-HEO and the other King Airs received Raisbeck designed modifications which included minor aerodynamic changes and the replacement of the three bladed props by four bladed Hartzell units, making the aircraft faster and quieter, improving its service ceiling and climb performance, and ensuring that 950m strips would never be a problem in the temperatures encountered in central Australia. High flotation landing gear was fitted as most of the strips the Service encounters are unprepared.

On VH-HEO’s arrival in Adelaide, the RFDS asked all the Adelaide hospitals exactly what equipment they wanted to see in a retrieval aircraft. This Project Definition study led to a two phase engineering program carried out at Parafield, Adelaide’s GA aerodrome just north of the RFDS Central Section’s city headquarters. Engineering consultants for the work were Australian Flight Test Services Pty Ltd of Technology Park, Adelaide, and the conversion was carried out by Parafield based Rossair General Aviation Pty Ltd.

The first phase provided the basic life support systems necessary for RFDS duties when VH-HEO entered service on 15 September 1987. The second phase of modifications in July 1989 saw the installation of the patient diagnostic and monitoring equipment, the addition of much-needed extra stowage space for medical supplies and equipment, and the fitment of the Stretcher Loading Device (SLD).

Theconversion program resulted in an exceptionally successful retrieval aircraft offering a level of patient care – particularly intensive care – superior to that found in many hospitals. The aircraft does not carry all the intensive care equipment all the time: it can be re-roled quickly, for example to carry a neonatal team and incubator from the Queen Victoria Hospital to a difficult birth in the morning, and then a differently equipped team from the Royal Adelaide Hospital burns unit to the site of a serious accident in the afternoon. The Central Section has converted two more Super King Airs since 1987 and other sections of the RFDS with similar time/distance problems have followed suit, buying and converting their own Super King Airs.

The Conversion

The conversion began, literally, from the ground up with the fitment of the high flotation landing gear. Internally, the fuselage was gutted: an independent 28V electrical sub-system with an 18 Ah battery was fitted to operate the medical systems; this allows independent operation of the medical equipment on the ground. With the engines running, the aircraft generators power the medical equipment and recharge the medical battery.

The medical electrical system powers a mixture of 28V DC and 240V AC power outlets, medical suction systems, special lighting and a stretcher loading device.

Two additional medical radios were fitted: a second HF radio covering the RFDS HF net, and a new VHF-FM system (powered by the medical battery) for the ground based St John’s Ambulance and RFDS VHF radio nets. A three station voice activated intercom system in the cabin allows voice communications by the medics and the monitoring of both medical radios as well as the pilot’s audio on the ATC frequency.

The medical equipment installation necessitated the replacement of the cabin’s floor and interior side panels. Except for the main spar running across the cabin aft of the flight deck (and which does not interfere with the medics or their equipment), the new floor is now a completely flat, easily removable honeycomb panel allowing quick access to the under floor medical electrical system. The floor and lower side panels are surfaced with sealed, non slip rubber material and the redesigned side panels fitted with recesses so that the various plugs and sockets for the medical and electrical equipment at each stretcher location are flush mounted rather than standing proud.

Overhead tracks on each side of the central aisle allow the fitting of sliding spotlights and hooks for intravenous drips. The King Air’s roomy cabin is therefore unencumbered by odd excrescences, which means it can be re-roled in a hurry to take seats, stretchers, incubators and even cargo.

The Ferno Washington FW-26 stretcher, which is standard throughout the South Australian emergency services, is used aboard the aircraft so that the patient need never be transferred from one stretcher to another between the injury site and the hospital. The stretchers are located on the starboard side of the cabin on the existing seat tracks using fittings which can be adapted to other stretcher types and to incubators. A third stretcher, an FW-107, can be carried on the port side of the cabin for serious emergencies.

To get the stretchers in and out of the aircraft a purpose-built Stretcher Loading Device (SLD), powered by the medical battery, is located on the port seat tracks just inside the cargo door and swung down when the door is opened to receivethe stretcher. This ingenious system was designed by Australian Flight Test Services to the RFDS Central Section’s requirements. “More and more women are joining the RFDS and ambulance service,” says Graeme Maughan, “And two smallish women would have one hell of a problem getting a stretcher with a 20 stone stockhand up to the level and into this aircraft. That’s why we need the cargo door, because manoeuvering a patient on a stretcher into the cabin through the normal rear door could be unsafe for a badly injured casualty. ” Australian Health and Safety legislation covering the causes of potential back injuries will almost certainly make systems like the SLD mandatory in certain applications in the future.

The SLD has been patented and discussions are in progress with possible American licensees to manufacture this unique but simple piece of equipment.

The Intensive Care equipment fit gives the King Air its full capability. Located just aft of the pilot’s and co-pilot’s seats, it consists of an Electro Cardiogram (ECG), a respiratory gas analyser and temperature, blood pressure, plethysmograph and pulse oximetry systems, all of which have alarms which sound through the cabin intercom system. Hard copy printouts of any of the traces is available through a printer so that the hospital has a record of the patient’s condition since initial treatment began. All the connections to the patient are available at his bedside, eliminating the rat’s nest of leads and wires which normally run direct from patient to monitor and which would really clutter up the King Air’s cabin.

Stowed alongside the Intensive Care systems can be heart defibrillator, foetal monitoring equipment, ventilators and syringe and infusion pumps, as circumstances demand.

A medical oxygen system was also fitted to the King Air, consisting of a kevlar-wound 3250 litre bottle located outside the cabin and replenished in exactly the same way as the aircraft liquid oxygen (LOx) system. Portable bottles are also carried.

Equipment

The RFDS has a difficult job: it attempts to provide urban levels of patient care, including preventive medicine, diagnostics, retrieval and convalescent care, across vast areas with a low population density. The quality of care its medical staff provides to the outback is legendary, but when faced with a victim of illness or injury speed is of the essence and the RFDS’s modified King Airs provide that speed along with flexibility, comfort and the ability to stabilise and monitor a seriously ill patient’s condition before arrival at hospital.

There is no doubt that the outback has never been better served than by the RFDS’s fleet of King Airs, and the similarly equipped Cessna Conquests used by theWA and Eastern Goldfields Sections of the RFDS. The various generations of aircraft used by the RFDS, starting with chartered Qantas DH. 50s back in 1928, have seen gradual improvements in speed, comfort and onboard medical facilities. The bigger and faster the aircraft, however, the greater the purchase price and the running costs. Some sort of compromise has always had to be struck between outright performance and affordability.

“At each of our locations we have one King Air and at least two Navajos or Chieftains,” says Graeme Maughan (Adelaide, in fact, has three Chieftains). “The slower Navajos are used for ‘Clinic runs’ in the main; the King Airs are our ‘retrieval aircraft’ they specialise in the life threatening, time critical situation. They are faster than the piston twins, they’re pressurised and, of course, they’ve got all this gear aboard. ” The King Airs fly about 600-800 hours a year, although the AliceSprings based aircraft flies around 1,000 hours per year; VH-HEO has flown 2,800 hours in RFDS service. “Even allowing for the age difference (the average age of the Adelaide Navajo fleet is around ten years), our piston aircraft have a statistically lower despatch reliability than our turboprops. ”

The RFDS (Central Section) Navajos and Chieftains, with an average age of around ten years, will be the first aircraft replaced under a recently announced ten year plan estimated to cost around $30 million. The aircraft with which they will most probably be replaced offer considerably more performance and space, making it possible for the RFDS to operate a fleet of aircraft all equipped to the same standard as the King Airs. This happy situation is as much as anything else the result of circumstances outside the Service’s control.

The RFDS has to be careful how it spends public money. Buying second hand aircraft, as was the case with the Central Section’s three King Airs, is all very well but it is estimated that even these low hour King Airs won’t last more than about 10 years in RFDS service. “Well, actually, they probably would,” says Graeme Maughan, “but the cost of maintaining them would go right up. Buying a brand new aircraft hasn’t been an option for us during the first phase of the aircraft replacement program. New turboprop twins are too expensive and the American product liability issue has killed the cheaper big piston twins which we used to buy new the last member of the Navajo family was built in 1984. ”

The problem is compounded by the lack of suitable King Airs on the second hand market. Only 137 were built with cargo doors for the civilian market, of which the first 37 were equipped with the Pratt & Whitney Canada PT-6A-41 turboprop engine. “With our ‘hot and high’ operations we need the extra performance of the -42 engines fitted from aircraft number 38 onwards,” says Graeme Maughan. “VH-HEO was aircraft number 39, the other two we have in Central Section are numbers 41 and 47. Only about 100 King Airs in the whole world actually meet RFDS requirements that is, they’re in private hands with cargo doors and dash 42 engines. The chances of finding a suitable aircraft on the open market in good condition at a sensible price are minuscule. The only one to come on the market in the last few years was about 18 months ago. We snapped it up.

“One of the other sections bought a King Air without a cargo door; in the end they had to install one because the risk of injuring a stretcher patient during loading with a standard door was too high. That cost them about $80,000. ”

The RFDS (Central Section) has cast its net a little wider.

Reluctant at first to abandon the security of a twin engined configuration, they have looked hard at the larger turboprop singles such as the PT-6 powered Cessna Caravan and Pilatus PC-12. The Pilatus aircraft, according to Graeme Maughan, has the right basic design and the PT-6 engine’s reliability record is outstanding. “VH-HEO has never missed a flight through unserviceability in nearly four years’ operation,” he declares.

The Central Section has led the rest of the RFDS in placing options on two PC-12s, subject to the aircraft meeting its performance and reliability targets in flight testing. With its big, spacious cabin, flat floor and cargo door, the Service is confident that the performance and facilities currently available in the King Airs will be available in the PC-12, with the advantages to the RFDS that the new aircraft would have a longer service life (conservatively 15 years before a fleet review is considered necessary), reduced maintenance requirements and far lower running costs overall than any aircraft in the current fleet.

Significantly, an all turboprop fleet will probably bring medical care even closer to outback communities which are currently two hours by air from the nearest doctor using the Navajo. Higher speeds and reduced maintenance will allow more sorties to be generated and will also mean that most communities are now only an hour and a half away from medical care. The doctors and nurses of the RFDS will be able to cover more ground, or cover the same ground more frequently, caring for their community while spending proportionately less time in the air travelling.

The debate on single versus twin engines continues within the RFDS and among its supporters. Graeme Maughan is quite convinced in his own mind. “We have calculated, based on our own experience with the PT-6 engine, that if we ran a fleet of 15 PC-12s for 600-800 hours a year each (the Central Section might order as many as seven aircraft), after ten years we would be only one third of the way to our first engine malfunction. ” He uses the term ‘malfunction’ deliberately: very, very few engine shutdowns, he maintains, are actually necessary they are usually the result of some sort of false indication on the flight deck. “In fact, the probability of an engine shut-down during the 15 or so years we would expect to keep a new aircraft in service is so low as to be statistically insignificant: to my knowledge, only one PT-6 engine failure has ever occurred in three and a half million flying hours. ” Crew training will not be a problem with the PC-12, reckons Graeme Maughan: ”All our pilots have now been converted from Navajo to King Air and could fly either aircraft, depending on how they’re rostered. So converting from a turboprop twin to a turboprop single will be comparatively easy and not too expensive; we’ve already paid most of the bill up front in converting our pilots from slowish pistons to higher performance turboprops. ” Pilatus has said that there would be no trouble in incorporating the special-to-type modifications such as the medical radio and electrical systems, SLD, oxygen, suction and patient monitoring connectors on the production line. The flyaway price of a brand new aircraft configured for RFDS duties would be around $2 million half that of a brand new King Air, and roughly the same as the service has been paying for its second-hand King Airs.