The Light Twin Is Dead, Long Live the Light Twin

While numerous start-up companies are working on clean-sheet light twinjet designs based on the low-cost Williams engines, Aerostar Aircraft Corporation thinks it has a better idea: mount a couple of Williams FJ-33-1s on its existing certificated Aerostar. The result, they say, will be a 400-knot six-place speedster costing under $2 million that will start customer deliveries in early 2002. If you're interested, the company is taking deposits.

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At a press conference a few years ago, Cessna had a one-word answer to aquestion about when it might resume production of its popular C-340 light twin:"Never." The light twins on the market have always been known asdemanding to fly, particularly when an engine fails. Piston twins, most of themunderpowered, tend to have engine-out performance that ranges from marginal tononexistent.

Several companies — including RAM and Colemill — have made good businessesout of retrofitting increased horsepower on light twins, but none have come upwith "the" answer. Even the up-engined versions of the aircraft are areal handful on one fan.

A study of accident statistics shows that turbine aircraft enjoy a muchbetter safety record than piston-powered ones. Part of that is pilot training,part is the lower incidence of engine failure, and part is the excess poweravailable if an engine does decide to go toes up. A King Air pilot told me thatan engine failure on takeoff is a "non-event," thanks to the hugeexcess of power available at sea level from the turboprop engines. "Allthat happens is the airplane climbs at about 700 fpm instead of 1,600," hesaid.

So it makes sense that the next generation of light twins would not bepiston-powered. What took me by surprise is that it looks like these newairplanes are going to bypass props altogether and go directly to pure jetengines.

As an enabling technology, the Williams FJ33-1 and other Williams enginesdefinitely qualify. These newer generation engines are less expensive thantraditional jets and offer superior fuel specifics and guaranteed operatingcosts. Williams will provide a Total Assurance Program that will cap engineoperating costs at $55/engine/hour. That figure includes all maintenance,inspections and overhaul costs for the engine. But now that we have pure jetengines that are beginning to rival the older piston powerplants in cost andefficiency, we need airframes to put them on.

Enter The Aerostar Jet

There are several companies now in development of light twinjets, but noneappear as close to having a real airplane than the Aerostar Aircraft Corporationof Hayden Lake, Idaho. Aerostar Aircraft owns the type certificate for thecurrently flying Aerostar originally designed and built by Ted Smith, and thenacquired by Piper Aircraft. Piper sold the type certificate, engineering data,tooling, and all the parts they had to Aerostar Aircraft shortly before Piper’sbankruptcy. Aerostar Aircraft has been supplying parts and upgrades to theexisting fleet for many years and now they want to get back into the business ofbuilding aircraft.

When Ted Smith originally designed the Aerostar, he had in mind a wholeseries of models starting with normally-aspirated piston engines, andprogressing through turbocharged, turboprop, pure jet. So from the verybeginning, the airplane had jets in its future. This isn’t the first airplaneTed Smith designed — he also did the B-25 bomber and the Aero Commader lighttwins. Remember what happened to the Aero Commanders? First the made them aturboprop and finally a pure jet. So Ted Smith designs have been through thisprocess before.

So, how do you get to the future? According to Jim Christy, president ofAerostar Aircraft, the Aerostar Jet has a tremendous head start because so muchof the work has been done. Ted Smith actually flew a model with the longerfuselage the Jet will have, and he did it with the new tail that will also be onthe Jet. "There are always some unknowns in a project like this," hetold AVweb, "but we can get a prototype flying a lot easier than if westarted with a clean sheet of paper." He estimates that Aerostar can buildand fly a prototype jet by March 2001 and have it certificated a year later withdeliveries scheduled in early 2002. "We have a production certificate nowfor the piston powered 600/700 series Aerostars, and it isn’t such a big leap tomove into the new model," he said.

The jet airplane’s projected performance numbers are impressive. Designed for6 to 8 seats and with a gross weight of 7,300 pounds, the Aerostar Jet willcruise at 400 knots, climb to 41,000 feet with a cabin altitude of 10,000 feet,and have a range exceeding 1,200 nautical miles. The Williams FJ-33-1 turbofanengines will provide a maximum thrust of 1,200 pounds each. Keep in mind thatthe current Aerostar Super 700 is the fastest piston twin, capable of more than250 knots at 25,000 feet. The jump to 400 knots with the Williams engines seemswithin reach.

Christy believes that since the Aerostar was originally designed with the jetmodel in mind, doing the work to get it there will be reasonably straightforwardand much easier than what most companies face when they start from scratch. Withthis in mind, Aerostar Aircraft is taking orders for delivery positionsbeginning in early 2002. Each buyer puts down a fully-refundable $10,000 deposit(you even earn the interest on your money). After the first flight of theAerostar Jet, the buyer must either commit to a purchase and make a seconddeposit of $50,000, or decide not to buy in which case his original $10,000(plus interest) will be returned. Projected delivery rates are about 50 aircraftper year and Aerostar Corporation is looking for the first 100 buyers.

But Will It Fly?

I have to plead some non-indifference here as I am a happy owner of my ownAerostar 700. The airplane is a true pleasure to fly and I have no doubt that ajet version would be even better. Of all the things I would like for my ownairplane, it is a longer cabin to make it a true six-place airplane and two morepowerful and reliable motors. Both or these are accomplished in the Aerostar Jetand much more.

Predicting success or failure of new aircraft ventures is a tricky business,but Aerostar has a lot going for it — not the least of which is that they havea flying model that isn’t too far from the newer jet model they hope to produce.The question they are asking the public today is: Do you want a 6 to 8 passengerjet that will cruise at 400 knots at 35,000 feet at about $1 per mile, all foran acquisition cost of $1,875,000 in 1999 dollars? If you do, you can vote withyour check for $10,000. The first ten positions are already filled, and whenthey get the 100 buyers the flying prototype won’t be far behind.

You can reach Aerostar Corporation at 800-442-4242 or 208-762-0338. Thecurrent Superstar 700 model is on display at EAA AirVenture near Exhibit HangarB.

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