Recent content by Niels


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    best 100 HP auto/motorcycle engine conversion?

    How many horsepower,prop rpm and prop diameter do You have in Your Deltajet Apollo to be competitive? How much mass is the engine,gearbox and prop? Lot of questions because I have a dream of something better. I have never piloted a trike but being passenger on some was very fun and pleasant.Best...
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    A FrankenFour Inline?

    For noise reasons tip speed have better be 220m/sec or less. What prop diameter is relevant for the aircrafts that will benefit from such an animal? Or asked another way how many rev per second?
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    Air Cooled Water jacket engine ?

    Some of the nicest german mopeds called SOLO used this system for years .Standard power was 2.1 hp from 50ccm 0r 40 horsepower per littre SOLO monkey
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    Aeromarine VTwin now in Electric Hybrid Version

    These kind of short ,big diameter electric machines can be a very good solution to torsional vibration problems. One at each end of a 6 or 8 throw crank will tame it for very low mass.
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    Are tube spars an insult to the engineering community?

    Blohm&Voss BV138 had tubular spar se eventual video here BV 138 fifty year under water
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    Lets talk about diesels.

    25 years ago I was trying to interest companies in something like that. All declined and quite a lot went bankrupt later anyway without my help. To keep the two cranks in step I dreamt of two bevel-gears and a carbon shaft. Torsional vibration calculations anyone? The new possibility is to omit...
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    Two cylinder gear-less twin aircraft

    These phenomenal slovenian electric machines from Emrax are axial flux and more compact/low mass than radial flux electric machines. I have found a drawing I made mid nineties of a non turbocharged radial flux enginerator. Junkerator was my very original name for it. To day I would have it...
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    Boeing - Design Issues...

    VW made some software that could detect when vehicle was on a test plant measuring NOx. Boing put in software to mask a fundamental flaw. What is most deplorable? What fines are reasonable?
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    Boeing - Design Issues...

    Professor Jan Roskam tells that Boing made three competing teams for initial layout of the new small,intercity jet for Lufthansa, that became 737. One design had engines on pods below swept wings like a B47(based on best german WW2 brainwork) One had engines aft like the french Caravelle and...
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    Two cylinder gear-less twin aircraft

    Let me try to calculate and hope for comments from people who know what they are talking about. We have a normal twin engine ship with two rotax 912 that can fly level on one( if handled rigth )as base. If 7000hours is realistic for a single 912 then it takes 49 million hours before we have a...
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    Two cylinder gear-less twin aircraft

    The big promise ,I think ,from electric propulsion is to have centerline thrust with very high reliability from two independent sources of electricity to one electric propmotor. Many years ago I read somewherer that piston engine twins make almost as many ugly things as singles. Is that still true?
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    Two cylinder gear-less twin aircraft

    Sorry for not explaining well enough. To displace Rotax 912 I propose to use one electric motor that can turn prop with 60kW at 40 rps. Electricity is supplied by either batteries,fuel cells or two enginerators of ca30 kW abillity each. Enginerators can have either two pistons in one cylinder...
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    Two cylinder gear-less twin aircraft

    Some millitary two stroke drone engines are around 15 kg for half a litre.In my scheme there is already a great part of the crankshafting in the generators plus some crankcase and there is no cylinder heads. Let us say 10kg for the Junkers parts and two times 4 kg for generators to make 30kW...
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    Two cylinder gear-less twin aircraft

    A cylinder of half a litre with two opposing pistons will make 40 horsepower at 100 rps if mean effective pressure is 7.5 bar.That is roughly a mixture of 3/4 fresh gas and 1/4 exhaust.If the strokes are 60mm we will need a cylinder inner diameter of ca 75mm.Pure outboard boat engine thermal...
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    Two cylinder gear-less twin aircraft

    Instead of making 30 kW using two cylinders and one generator ,we can use one cylinder two pistons and two phaselocked generators as I demonstrated around 1994. There is no specific electric machine in the Emrax range for 15kW but an Emrax 188, where all axial dimensions are halved, will be a...