P-51C at ~70% scale as ultralight?

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by J.L. Frusha, Apr 30, 2019.

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  1. Jun 12, 2019 #301

    Lendo

    Lendo

    Lendo

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    MC 104, Their all good but approaches do differ, I will buy a book and be happy to get just one, (what I call) 'Golden Nugget' of information. I paid $500 Aust. for one book.
    Naturally members on here have been extremely helpful as well.

    J.l. Excel is a good standard, I know Roncz has used different ones, but unsure what they are - as long as they do the job. I will be looking forward to your success, as I find you project interesting.
    George
     
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  2. Jun 16, 2019 #302

    J.L. Frusha

    J.L. Frusha

    J.L. Frusha

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    Been a busy week working on a Biogas project and playing family chaufer. Too much going on to get anything done on this, right now.

    I live on a goat farm and will be putting in a 9 acre Alfalfa field, probably using Subsurface Drip Line watering. Definitely going to be a challenge to overcome the rocky soil..
     
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  3. Jun 18, 2019 #303

    Lendo

    Lendo

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    J.L. Some things are not always obvious in other peoples Spread Sheets (SS). Not to say their wrong, I just like to know all that goes into the calculations, for my own education and clarification. If you do your own SS with good notations, going back to check things makes it so much easier. Mind you I learnt the hard way.
    George
     
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  4. Jun 18, 2019 #304

    J.L. Frusha

    J.L. Frusha

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    Thank you. I don't know enough to properly use all of the features in the ones I have found, but I really do NOT have the background to set up a spreadsheet on my own. By using multiple spreadsheet calculations, I figue I'll at least be able to get a decent approximation of the values.
     
  5. Jun 18, 2019 #305

    BJC

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    There are lots of spreadsheets available, and some are good. All require an understanding of the embedded assumptions, approximations and formulas. Always do, or get, a sanity check on all results. And enjoy the chase.


    BJC
     
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  6. Jun 19, 2019 #306

    Lendo

    Lendo

    Lendo

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    BJC and J.L., Who was it that said Aeronautical Engineering are approximations to 8 decimal points.

    In my most humble opinion, if you can maintain accuracy to a high degree, going into formulas/ calculations - you're a better chance of getting something reasonably accurate as a result.
    LIke computers, shite in - shite out.
    George
     
  7. Aug 2, 2019 #307

    MadProfessor8138

    MadProfessor8138

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    How far along on the design are you now ?

    Kevin
     
  8. Aug 4, 2019 #308

    akwrencher

    akwrencher

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    Can't find it right now, but I believe the quote is something like "aeronautical engineering is highly educated guesswork worked out to several decimal places", IIRC.
     
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  9. Oct 3, 2019 #309

    MadProfessor8138

    MadProfessor8138

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    Any progress to report ?

    Kevin
     
  10. Oct 3, 2019 #310

    J.L. Frusha

    J.L. Frusha

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    Tied up starting a family business and running a goat farm.

    Stepson that was doing the farm work had his grandmother die and has been trying to help his father get the estate settled, so I'm working 7 days a week for no pay...
     
  11. Oct 3, 2019 #311

    MadProfessor8138

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    Sorry to hear that and I wish all of you well.

    Kevin
     
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  12. Oct 4, 2019 #312

    radfordc

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    And so ends the story of the exact scale P-51 ultralight.
     
  13. Oct 4, 2019 #313

    J.L. Frusha

    J.L. Frusha

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    Nope. And it wasn't exact scale, after all the discussion.

    Delayed,... yes. Starting a new family business is nothing to sneeze at and you damned well know it.

    How many people actually SUCCEED in a build, if their spouses, family and friends do not support their project?

    You want to piss on a parade, go piss on your OWN parade. I have more than one iron in the fire and a herd to brand, so you can kiss my @$$
     
  14. Oct 4, 2019 #314

    MadProfessor8138

    MadProfessor8138

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    Life gets in the way sometimes.....
    Take care of yourself & family then the rest will fall into place.
    It's perfectly fine to have delays.....hell,I've got 2 aircraft drawn out that I've been pondering solutions to various problems over the past few years.
    When the work gets overwhelming just keep the design in the back of your mind and you would be surprised how often you subconsciously solve an issue and you didnt even realize you were thinking about it.
    Helps the day go by a bit easier....

    Rome wasnt built in a day.......

    Kevin
     
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  15. Oct 4, 2019 #315

    BBerson

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    Ultralight design takes years. Can be done on spare time here and there. Like when trying to fall asleep.
     
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  16. Oct 4, 2019 #316

    J.L. Frusha

    J.L. Frusha

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    I keep playing with the lines on the 'Shetland Pony' (shortened ahead and aft of the cockpit).

    A touch here, redo that , etc., when I need a total break from the financial concerns, science and engineering aspects of what I am trying to do for our family business, which has applications from the cheapest porta-John to military applications.

    Flip side of the business plan is a nonprofic to take my design to the needy, especially in food and energy poor areas.

    Safe, sanitary use of organic waste, to make fertilizer and fuel.

    Inspired by the Gates Foundation "Reinvent the Toilet" challenge.

    I HAVE goals and dreams, but I have a MISSION to do what I can to make the world a better place.
     
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  17. Oct 10, 2019 #317

    rotax618

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    This model is a an idea for a 60-70% Corsair.
     
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  18. Oct 10, 2019 #318

    J.L. Frusha

    J.L. Frusha

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    Nice! I like it!

    Similar, but it looks like the scale of the pilot is off.

    I was fortunate enough to find plans with seated pilot to work with, for my cartoon scale P-51 'Shetland Pony' idea.

    Started with ~ 70% scale and it just didn't look/feel right to do what has been done, so I started playing with compressing forward and aft of the cockpit, but retaining the wings and tail-feathers.

    You know, it is said that 'if it looks right, it should be right'... mainly meaning ugly planes probably aren't as aerodynamic as those with smooth, clean lines.
     

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