Hawker’s Hot Rod Helo

Many men and women of persistence have succeeded in their visions, enduring real personal hardships because they had the courage of their convictions. Listing some of these would be superfluous, but we point to a recent example (in a recent edition of MOR) as being a prime subject – the little two-place Robinson R22.

Also in Australia is another working example of what a man can do if he believes in his dream – the Soloy Conversions.

Sitting quietly at the 1981 Schofields Air Show was a Bell 47. It didn’t look all that much different from the front end, but when one looked astern, the difference was staggering . . .

In place of its usually-expected 270 hp Lycoming sat a power-filled Allison 250 turbine, representing the first of its type in Australia.

Alongside the chopper sat Hawker de Havilland Australia’s Service Manager – Helicopters, Hank Hendry, who told us something of the Soloy Story. More than that, he opened up a completely new world in terms of a gas turbine conversion’s scope in this country’s often hot environment which has more often than not limited choppers’ payload and range to a significant degree.

These factors have in turn probably helped to slow down the acceptance of this agile and versatile form of workhorse. Joe Soloy was just another helicopter pilot back in 1963. . .

But he had this dream, you see. It was a vision so stark, so logical, that he just had to put it to the test.

Joe, like so many other helicopter operators, was limited by his steed’s tenderness to height, heat and the dreaded humidity.

He was particularly anxious to eliminate the critical time/payload disadvantage when using choppers in the logging industry – a peculiar operation often needing the winching-out of split logs from high and oft-difficult terrain.

Soloy began really working on his vision in 1967, but it was not until April 10, 1975, that it all came true.

On that date, the FM certificated a little Hiller UH-12E-J3.

And the Soloy Story has gone right on from there. . .

He has a far-reaching program of re-engining Hillers and Bell 47s with new Detroit Diesel Allison 250-C20B gas turbine engines.

One of his conversions, a Hiller, has become the only chopper in the world to work off the top of 21,000 ft Mount McKinley (Bud Woods, of Woods Aviation, Palmer, Alaska, made a landing at 21,000 ft density height to rescue two mountain climbers), and Australian operators are looking searchingly at the Soloy conversion which may provide an answer to the hitherto limited inroads able to be made in outback, scorching heat operations.

One of the major factors most are weighing up is the power reserve element; the ability to fly at gross weight with that reserve up one’s sleeve.

Dependability, ease of maintenance and the low downtime needed with the magnificent Allison, operational costs and choice of installation methods, are other most desirable things to consider.

Figures prove the all-over enhanced performance of, say, a Bell 47, with the new Soloy conversion.

A 47G’s empty weight drops by about 200 lb when the retrofit is complete. Engine life almost trebles.

The hook weight has gone up to 1000 lb.

The only thing pilots can spot – if they’re looking hard – is that the CG has shifted slightly aft when the fit is complete.

What does Soloy retrofit entail? Certainly much more than hefting out the old Lycoming and buttoning on a shiny new Allison.

Basically, the original Bell cooling fan and clutch have given way to a Soloy speed-reducing gearbox; a completely new 24-volt system with the battery housed forward; new low-profile instrument pedestal; hydraulic pump on the transmission instead of on the engine – this, says Joe Soloy, enables powered controls to remain operative even if the engine stops; new crash-proof fuel tanks with breakaway tank mounts.

It depends on the transmission used whether you derate the mighty 420 shp Allison to 261 or 270 shp. Compare the rated and de-rated figure to estimate what massive power you have in hand for those tight spots. . .

It works out that, depending on the transmission, you only use 61. 9 per cent or 64. 2 per cent of the total power available from the engine under normal circumstances.

Soloy has issued a long list of prerequisites for conversion, for both Bell and Hiller. Among the biggest “must haves” for Bell operators wanting a Soloy job done on their machine,, the patient must have tip-weighted rotor blades and duplex hub bearings, late model tail rotor gearbox and the latest tail rotor with 2500 hr life.

The collective must be fully powered.

When the job’s done you could be looking at an overall $109,000 including the new motor, says Hank Hendry.

A host of accessories are available; they include flotation landing gear; cabin heater; external load support system; cargo hook assembly; dual collectives; hydraulic drive assembly; hydraulic reservoir assembly, and a particle separator and mist eliminator system.

The particle separator and mist eliminator is worthy of mention. It’s made by a subsidiary of Pall Corporation, Aircraft Porous Media Inc. , at Glen Cove, Long Island.

A must for off-road helicopter operators, it’s a self-cleaning item, giving low-pressure drops and without filters to change. There are no moving parts.

All this adds up to an exciting picture, a portrait of things to come in the fixed-wing field if other operators, people with vision, get their act together. In the meanwhile, Soloy has realised his dream and proved it with reality.