flyvulcan

Milton King’s Lightning Bug flew for the first time a few weeks ago at Murray Bridge Airfield. Ted King took it aloft for the flight which lasted around 20 minutes. Other than some oil cooling issues for the Jabiru 3300, the aircraft flew well. Speed was kept to a maximum of 150kias straight and level. Since then, the aircraft has been flown 3 more times. The speed envelope has been expanded out to 175kias straight and level with plenty of power still left in the engine. The IFA Ivoprop Magnum is not the right prop for the aircraft and has not yet been taken off the low pitch stop. Climb is at 2400 rpm (so way down on power due to the too highly pitched prop) giving 1500fpm. With the right prop allowing the engine to turn faster, rate of climb should be much improved. Top end straight and level will also be much faster than 175 knots. We are looking forward to seeing what this Lightning Bug can ultimately give in the way of performance.

Will do Peter. I anticipate that the Arion Lightning should arrive back in Adelaide around September/October. It will go into the workshop of my companies facility in Mile End, next to my jet project. I plan to have a workshop visit for local enthusiasts to show off both the projects and give everyone an update on the progress of my 200hp turboprop engine. I must get down to Goolwa to look over your Onex. I’ve been back from the desert for 2 years now but still haven’t caught up with everyone that I’ve wanted to. Between the business and family, I don’t get much time... Cheers, Dave

I am undertaking the first week of the Arion Lightning builder assist program for the Lightning that I just ordered in the first week of July. I’d be happy to report my experience here so that you have an idea of what to expect. My Lightning will have our (currently under development) 200hp turboprop engine in it. That is really going to be interesting! Dave

Coot amphibian

Thanks Ian, I’ll take you up on that offer. I’d like to get as many ideas as possible before heading over to the US in July to attend the builder assist program. I’ll pm you with my contact details. The aircraft will be the company test airframe and then demonstrator in Australia for our 200hp turboprop engine that we have under development. Dave

Still going well Ray and still dabbling in turbines (www.turb.aero). Next time I’m in Sydney, I’ll come visit you at Camden. My engines and your aircraft could be a good mix. Dave

The Vne increase has been determined through consultation with the designer. He had already developed a mass balance solution for the elevator and we will be incorporating that modification into our kit. The structural design element has been determined to be satisfactory and the aircraft has been dive tested without the mass balance fitted to beyond our target Vne (200 ktas). We want to be able to cruise at 180 ktas so the 200 ktas will give us some margin over our intended cruise speed. My friend with plenty of hours on the aircraft has no concerns about the gear. The only issue he has is with gusting crosswinds. He indicated that he finds them challenging but admits that it may be his own skills rather than an issue with the aircraft. I cannot comment on grass strip capabilities.

Ray, about 35 years ago when we were mucking around with my lpg powered pressure jet engines, you had an almost complete Stingray kit in your hangar. Did that ever get finished?

I ordered an XS just last week which will be delivered to the Build Assist shop during the first week of July. I am looking forward to carrying out the build under the supervision of the experienced build assist staff. Once the airframe is essentially finished, other than fwf, it will be shipped back to Australia to receive a panel and fwf. We will be putting a 200hp engine which we have under development into it. All flight controls will be mass balanced and the Vne will be increased over the current 180 ktas. The optimum cruise power for our engine will be 180hp at 10,000’ but we will be able to pull power back to 150hp without impacting sfc. Consequently, we should have a very handy cruise speed if we want it. I have not flown one but have some friends who own one. They are very complimentary about its flying characteristics. One of them is a 6x Lightning builder with many hours in it. I tried his latest build on for size last week, just before ordering our kit.

My mistake. Cliff was at Bondi Junction. I remembered it was near a popular beach and your mention of Bondi refreshed my memory...

Did Clifford van Praag sell the Sky Rider from his place near Manly? When he did my BMW K750 conversion about 30 years ago, I’m sure he had one of his kits in his shed.

A tragic outcome. Hopefully the authorities can determine the cause quickly in order to prevent similar occurrences in future.

Nev, our engineers will determine whether a torque measurement/indication will be required. I cannot say at this point. The display that we anticipate will be an N1/N2 (gas generator shaft speed and power turbine speed) expressed in % of maximum, or possibly an N1/Prop speed display. Being a constant speed prop system, the power turbine will normally be running steadily at its optimum % while the gas generator % will change to reflect power. So the pilots primary power reference (for Power + Attitude = Performance) will be a % figure. As an example for those interested I give the following (figures are only an example and are not true figures): For a TA120TP powered Lightning Bug with the XXX propellor system fitted, a 250ktas cruise at 10,000’ on an ISA day will require the following: 1 degree nose up and 85% N1 indication.

We aim to rate our engines as follows (at sea level, STP): TA120TP: Take-off power (5 minutes limit) - 120hp Maximum Continuous Power (MCP) - 110hp Optimum Cruise Power (OCP) - 100hp TA200TP: T/O Pwr - 200hp MCP - 190hp OCP - 180hp We are going to attempt to have a fairly flat SFC curve for the 80-100hp range for the -120, and 150-180hp for the -200. This will allow the pilot to pull the power back from the OCP figure, but still achieve a similar SFC at the lower power. We can’t guarantee this but we will be striving to achieve it.

We will likely brand our unit something like a “Power Control Unit” which will simply be a combination of an Engine Control Unit (ECU) and a prop controller. Our challenge with the prop pitch control system will be to have a system that can alter pitch at a high rate, in order to keep up with the potentially rapid rpm changes of the power turbine. We intend to work with a single prop control company to develop this mechanism (if we cannot find a suitable off the shelf product). We will work with that prop hub company and some blade manufacturers to offer a range of hub and blade options to suit whatever application the engines may be used in. Due to the dangers associated with operating a turboprop with an incorrect prop system, we will offer only a single prop system option with our engines; one that we will have thoroughly tested. We have used a fairly good ECU system on our proof of concept engine but we want to develop a more robust unit that offers redundancy in the event of a component failure, so you can anticipate a dual channel control system with no common components. So much to think of... so much to do... Fun times ahead!

It will likely go in one of these as we have a great relationship with the manufacturer: If you want one, they are available in Australia. See The Flying Legend | Your new aircraft or PM the user Tucano on this site. I'm sure he'd be happy to hear from you! Dave

Funnily enough, we have had a lot of interest from the low and slow community. Mainly from the perspective of short field take-off and landings. The light weight of the engine combined with the constant speed prop offering both static and dynamic thrust, as well as the potential for beta operations has some of the Cub type manufacturers interested. Sure, their loiter fuel flow wont be good but those dirt strips, river sandbars etc. may become that little bit more accessible. BTW, the engine will only come with a CS prop that is fully controlled by the ECU. We intend to offer a selection of gearbox ratios in order to allow different sized props swinging at different speeds. The prop rpm will be set to match the reduction gear ratio optimum output speed so that again, the single lever throttle control will simply be a more power/less power, go faster/go slower, climb faster/climb slower scenario for the pilot.

We are offering an AK47 and some white powder with each engine sold... PS for any law enforcement officers that read this, that was a joke!

Nev, we intend to address the existing market first which means propellors. That just makes economic sense. However, being a jet guy myself, we intend to move into that space once the company has financial security. I need a couple of 150-200lbf jets for my Jet Bug (Komet) but we are looking at the 4 seat personal jet market downtrack which we believe has good potential. In this class, 2 x 500lbf turbofans would give the 4 seat personal jet reasonable performance.

Part of our strategy is to seek an FAA amendment to the LSA regulations in the US to permit the use of turbine engines in LSAs. The submission has been prepared but we are waiting for our next prototype to run where we can demonstrate the “simple” operation of the engine through its single lever control, as well as extol the safety benefits of an engine where the pilot never needs to look at his engine instruments (I’m definitely not suggesting that is what should be done!) as the engine control unit will ensure that no engine parameters are ever exceeded. For the pilot, it will be a case of starting the engine by pushing the button. Thereafter, more power push the throttle forward; less power, pull it back. Easy, the ECU controls both the engine and propellor so that the pilot doesn’t have to worry about mixtures, carby heat, prop control etc. Simple! If we can get the FAA to amend their rules, it will be easier for CASA to follow.

These are the two areas that we are paying significant attention to in order to make our products viable in the market. Historical perceptions/facts should not be applied to what is available now. The technology is there to address these historical issues with small gas turbine engines and we are applying the latest proven technology to deliver a product that should change those historical drawbacks of high cost and high fuel burn. Thanks to the recent significant advances in the capabilities of the design and analytical software, the huge reduction in cost of that software, the reduction in cost of the “exotic” materials needed for a turbine and the significant reduction in costs associated with the manufacturing of the precision components needed for turbines, the time is now right to develop a lower cost turboprop. To address the historic high fuel burns for small gas turbine engines, we are incorporating recuperator technology which improves specific fuel consumption considerably, with acceptable downsides of weight and volume. Our target is a maximum SFC of 0.55lbs/hp/hr at Optimum Cruise Power. Initial indications are that we may be able to do better but 0.55 is the target maximum. Yes, that is a little more than the equivalent power pistons, but not a lot.

Hi everyone, as requested, here is an update on the program. Turbine Aeronautics received an injection of funding recently including a South Australian Government grant. This funding has allowed us to proceed full steam ahead with the program. On the boring side of things, we have moved into our new corporate offices in Adelaide which includes a good workshop facility. We have recruited administration staff and our corporate infrastructure is now robust to move ahead (very important for a business!). Earlier this year, both during and in the months after Oshkosh, the Executive Management team was busy visiting potential design program participants with a view to finalising the design teams for the program. We have a number of highly specialised components that we are incorporating into our engines to ensure that the required fuel efficiency and reliability/maintainability targets are met. We have been extremely fortunate to have some of the leading companies in the world in their area of expertise on board for our program. I had better mention here that for commercial reasons, we have chosen to launch with our 200hp engine, but rest assured that our 120hp engine should follow up about 6 months after the 200hp engine. This has been a popular decision amongst the kit manufacturers with whom we have formed close relationships and who have encouraged us to offer them the 200hp engine first. The technical program is well and truly underway for the 200hp engine and we are waiting rather expectantly for the first phase of the analysis process to be completed where we will have fairly accurate (theoretical) specifications for the engine. The good thing about the current analytical software tools are that they are now very accurate in predicting actual conditions (within about 1%). The design work for some of the components/systems is underway and the detailed design work for the major components will start shortly, after completion of the analysis that is currently being undertaken. Our timeline according to our current schedule has first deliveries of the 200hp engine during Q4, 2019, around 2 years from now. Early next year, a new website will be published. We intend to run a Blog on the website, giving frequent progress reports on the program so that enthusiasts can follow our journey. Let me say in closing that this is a huge and complex program. However, the planning that has gone into it is extensive; the quality of our design teams is extraordinarily high; and we as a company are determined and focussed to make this a success and bring the first commercially available, affordable turbine to the guys like you and me that want one in their aircraft. For me, it will be a 200hp Lightning Bug, for you, it may be a 200hp Arion Lightning, or a 120hp Turbine Jabiru or... Here’s a question for you guys, what airframe would you like to see a 120hp or 200hp turboprop in? Cheers, Dave

Let’s try this one...

BF109, Spanish civil war era, probably C or D model

Arion Aircraft, LLC Some progress photos of the 200hp Lightning.