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Thread: Oddball engines and prototypes

  1. #2866
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    electric? not so fast. I want / need to be able to fly my gyro four hours without landing and refueling. IC will do that for me at the moment, electric would be closer to maybe half an hour, at the moment. Not enough.

  2. #2867
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    Quote Originally Posted by Flettner View Post
    electric? not so fast. I want / need to be able to fly my gyro four hours without landing and refueling. IC will do that for me at the moment, electric would be closer to maybe half an hour, at the moment. Not enough.
    See what I mean? - all you need is an old EA81 (pushrod) Subaru for starters, get 'that guy' from Waikato to give it a going over and hey presto! - everything's there , like a four stroke which revs low enough (to manage without a reduction gearbox) and is economical and uses the 'thirties' technology we were discussing - everything you need! but if you want something lighter then you can try a two stropke (they are available from 'that guy' too!)
    Strokers Galore!

  3. #2868
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    Napier was at the forefront of IC engine development for a long time. They developed fighter aircraft engines with very high power for their frontal area starting the W layout Lion and ending with H design Sabre. The Deltic was probably the last successful refinement of the opposed piston engine. In the end, these engines complexity was their downfall. In aircraft we have turbines, and in two strokes we have crankcase scavenged tuned pipe engines. My lawn mower and weedeater have an electric motors. Less is more.

    Lohring Miller

  4. #2869
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    In aviation there is still a need for reliable mid horsepower work engines and the old school radial engine takes care of that at a fraction of the cost of a turboprop engine..I work with some ag aircraft(crop duster) guys and they still prefer the radial for low overhaul cost,cheap to maintain,low fuel burn..The bigger players prefer turbines,but must work year around flying across the nation for work to keep up with their million dollar ag plane payments.insurance.and maintenance costs in check..Its their choice!
    Back to the loved 2stroke,their beauty is every stroke is a power stroke!No wasted pumping stroke..I am all for different 2stroke configurations,oiled bottom ends is even better!I'm not an engineer,but feel a 2stroke engine can deliver more even torque at a lower RPM with a smaller simpler size than the normal stuff...

  5. #2870
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    Quote Originally Posted by lohring View Post
    Napier was at the forefront of IC engine development for a long time. They developed fighter aircraft engines with very high power for their frontal area starting the W layout Lion and ending with H design Sabre. The Deltic was probably the last successful refinement of the opposed piston engine. In the end, these engines complexity was their downfall. In aircraft we have turbines, and in two strokes we have crankcase scavenged tuned pipe engines. My lawn mower and weedeater have an electric motors. Less is more.

    Lohring Miller
    Lohring,
    Much as I hate to admit it, in the mechanical world, most of the innovations were in the twentieth century and I hope we are now sifting through the tailings to find any discarded gems and refine them. The electronics world continues upward but it's very fragile and is vulnerable to outside interference (in all sorts of ways) and I don't think it's sane to rely on it as much as we do!).
    I think that the only upside of this virus is that it has made many us forget the world of fantasy we have been living in, take stock of just where we actually do stand in terms of human existence- and settle for less! ....... (which is more! ).
    Strokers Galore!

  6. #2871
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    Quote Originally Posted by 190mech View Post
    In aviation there is still a need for reliable mid horsepower work engines and the old school radial engine takes care of that at a fraction of the cost of a turboprop engine..I work with some ag aircraft(crop duster) guys and they still prefer the radial for low overhaul cost,cheap to maintain,low fuel burn..The bigger players prefer turbines,but must work year around flying across the nation for work to keep up with their million dollar ag plane payments.insurance.and maintenance costs in check..Its their choice!
    Back to the loved 2stroke,their beauty is every stroke is a power stroke!No wasted pumping stroke..I am all for different 2stroke configurations,oiled bottom ends is even better!I'm not an engineer,but feel a 2stroke engine can deliver more even torque at a lower RPM with a smaller simpler size than the normal stuff...
    I guess those AG planes were originally built to take advantage of the thousands of cheap, well developed radial engines which were left over from WW2!

    Two stroke power? - Yes but it will still face opposition by many quoting from the same old book of prejudices against it, we will have to rewrite the book and give it a new presentation! - today's upgraded (but still traditional) design will convince no one to change - present two stroke design (as I see it) will work well for competition perhaps - but not universally be accepted, powering other vehicles and in this important area it has already been well and truly stymied! - but there's no profit in being a pioneer either!
    Strokers Galore!

  7. #2872
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    Don't worry guys, I got this😆
    Uniflow for aviation, two cranks , no need for counter balance shaft and there is an exciting option of twin counter rotating props. Any engine IC of any worth still needs a gear reduction anyway, if you are looking for efficency.
    Will D, my Subaru EA81 powered gyro even has an Autoflight gear reduction ( torque multiplier ) or it would be a slug to fly.
    Splitting the exhaust away from the inlet has big advantages.
    Compare my Uniflow 440 engine to say my EA81.
    Uniflow has two cranks but the same amount of connecting rods and crank journals as the EA ( so could be argued the same), Uniflow has no heads or valves or push rods or rockers or camshaft. Same number of pistons. Uniflow could live with two carburetors or FI same as the EA. Uniflow has four gears, EA has two gears ( cam drive ) plus two redution hears, so the same, EA has and oil pump, Uniflow not. EA has a sump, Uniflow not, same amount of spark plugs on both.

    So only thing extra on the Uniflow is some reed valves.

    EA, extra is, cam, lifters, push rods, rockers, valves, sump, oil pump, heads, you have to take into account the gear reduction so same number of gears and it only fires half as often.

    Seems the Uniflow is the clear winner. Make it HCCI and I'm sure it would be so efficient, it would be making fuel. 😆

  8. #2873
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    A clean sheet required, and clear workshop bench.

  9. #2874
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    Quote Originally Posted by Flettner View Post
    A clean sheet required, and clear workshop bench.
    Oh well, sorry for my ignorance in the engine/prop department ( I tend to be looking from the perspective of light fixed wing aircraft) but I know I probably get people so wound up sometimes that they might feel the need to correct me ! )..... and that's great, ..... I hope they do - that way I can learn more! - )
    Also, it looks like I possibly could have been wrong in the foundry thread in thinking that you were reviving the Cre'cy again ! - I could be forgiven for thinking that though! ........ and now, two cranks on a new aviation engine idea - never ending!
    Good comparisons given between it and the EA81! (don't scrap the EA81 just yet though!) .... anyway we'll wait and see everything unfold.
    .
    Now that the Oddball thread and the Foundry thread are both going again, - the ESE thread has decided to stall! - that's unbelievable! it used to be packed with so much stuff it could hardly breathe! - someone needs to kick start it as well guess, - not me, it's not my domain!.

    I guess the Virus is having an impact because it has closed down all Bucket Racing activity!!
    Strokers Galore!

  10. #2875
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    Places where high continuous power is needed (ships, airplanes) will use IC engines for a long time. However, I worked at an electric boat company that has been building electric powered "boats" for a very long time. Today these "boats" are using lithium ion batteries. The batteries are replacing sterling engine systems. Noisy diesel generators are still used for recharging. Aircraft need lighter power plants than ships. Even so, short haul planes are currently being designed for battery electric power. See https://www.businessinsider.com/elec...lations-2020-3

    My favorite spray plane pilot survived flying biplanes in the early days of post war aviation. I had a ride in his N3N when he was still flying. Those big radials are impressive. These days he's 88 and flies as a passenger in his wife's Bonanza. He still does aircraft inspections as an ATA certified mechanic.

    Lohring Miller

  11. #2876
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    lohring, boats easy, a bit of weight in the right place is a good thing and if it all stops no big deal.
    Autogyro is a power hungry aircraft, power density is top priority. And if it all stops you aren't just floating around, you are ' floating' down. In fact the modern gyro didn't really shine until a suitable twostroke turned up. Early examples used McCullough military drone engines, 72 HP, the weight of a loaf of bread (almost) suddenly the personal gyro was a real thing. Thank you Dr Benson.
    In my opinion a uniflow twostoke would be the ultimate IC power plant for a gyro, power and efficiency.

  12. #2877
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    Quote Originally Posted by lohring View Post
    Places where high continuous power is needed (ships, airplanes) will use IC engines for a long time. However, I worked at an electric boat company that has been building electric powered "boats" for a very long time. Today these "boats" are using lithium ion batteries. The batteries are replacing sterling engine systems. Noisy diesel generators are still used for recharging. Aircraft need lighter power plants than ships. Even so, short haul planes are currently being designed for battery electric power. See https://www.businessinsider.com/elec...lations-2020-3

    My favorite spray plane pilot survived flying biplanes in the early days of post war aviation. I had a ride in his N3N when he was still flying. Those big radials are impressive. These days he's 88 and flies as a passenger in his wife's Bonanza. He still does aircraft inspections as an ATA certified mechanic.

    Lohring Miller

    We still (as far as I know) use DH Beavers for fertiliser drops in the hill areas of this country (NZ) - they were first brought in for that purpose from Canada a long time ago - I think the in late fifties and were assembled here by the father of a friend of mine, and of course used the big radial engines - so that shows their reliability!
    We also have a home grown topdresser here called a Fletcher, which has been operating from those days as well and it used a Lycoming or Continental flat 6 and has been around for a very long time as well - there was a modified version fitted with a turboprop (now called Cresco) - and unfortunately just last week, one crashed on takeoff, killing the pilot.

    https://en.wikipedia.org/wiki/PAC_Cresco

    Neil, ( I know that we're deviating a little from the bike stuff but it's still relevant so long as we get back again I hope) ....... I was familiar with the contra rotating twin prop scenario - In N. Ireland, where I grew up, our farm was close to an RAF base operating the 4 engined Shackleton bombers which used the RR Griffon engines (with contra rotating twin prop).

    https://www.pinterest.nz/pin/382383824590278960/

    Also close was a RN Base which operated the Fairey Gannet (carrier anti submarine aircraft) which used Twin Mamba Turboprop engines coupled to a twin prop setup - these engines could be used as seperate engines as well! but... noisiest things on the planet!

    https://www.faaaa.asn.au/heritage-fairy-gannet/
    Strokers Galore!

  13. #2878
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    Noisy, they were not doing it right.

  14. #2879
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    Quote Originally Posted by Flettner View Post
    Noisy, they were not doing it right.
    Not sure if it was the engines (unlikely) or the props - probably shock waves from the prop tips - but bloody noisy .... they easily rivalled the Harvards at takeoff!
    Strokers Galore!

  15. #2880
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    Quote Originally Posted by WilDun View Post
    Not sure if it was the engines (unlikely) or the props - probably shock waves from the prop tips - but bloody noisy .... they easily rivalled the Harvards at takeoff!
    https://youtu.be/elENLa01XHA?t=993

    contra-rotating propellers have been found to be between 6% and 16% more efficient than normal propellers.
    However they can be very noisy, with increases in noise in the axial (forward and aft) direction of up to 30 dB, and tangentially 10 dB. Most of this extra noise can be found in the higher frequencies. These substantial noise problems limit commercial applications
    https://www.rcgroups.com/forums/show...mentid=2815700
    Quote Originally Posted by Katman View Post
    I reminder distinctly .




    Kinky is using a feather. Perverted is using the whole chicken

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