Another C152 - freeware

  • Well I eventually managed to give her a test fly!!


    Thank you so much Sylvain, you did an outstanding job with such a very high standard 3D model, congratulations!

    Would this C152 have been designed by some well-known professional third party editor using expensive tools I would have said it's a brilliant job - therefore I'm even more amazed you did it with Sketchup! Hat's off!


    The cold and dark situation is gorgeous.

    The sounds are pretty good and immersive, turning back to the dull sounds of the DR400 after the C152 run sounded really disappointing to me (I need to work on it).


    I think the flight model however could benefit from Jan's experience and support if he reads those lines. You obviously picked the C172 base, which is sure the best method to start with, but the light C152 kept the engine power and many other features of her heavier big sister.


    As a result, at brake release the speed jumps to 70kt in no time before rotation eventually gets possible, and then the C152 rockets to the sky with an initial climb rate of nearly 2'000 ft/min - it felt like JATO-assisted takeoff.


    As long as you keep flying fast, she does it smooth and gentle, still with exaggerated power. But when reducing, speed control is nearly impossible whatever the flaps setting, with a very heavy nose when approaching 70kt and immediate stall below (should be some 40kt). Applying full flaps you hardly can reach 65kt before stalling (should be below 35kt). Then, of course, getting back to the AD I carrier-landed her 3-points full flaps at 70 kt without being able to flare despite full yoke deflection.


    I had no time to dig too far into the TMD file yet: reducing engine power to the 82kW of the 235 Conti is not enough, there's obviously more to it, but if Jan is willing to support you I guess in no time you will bring the flight behaviour to the same standard as that gorgeous model.

    Please don't take me the wrong way, it is really meant to be constructive only and I'm very grateful for the work you share with us.


    So, thank you so much Sylvain ! keep up the good work


    Cheers

    Antoine

    Config : i7 6900K - 20MB currently set at 4.00GHz, Cooling Noctua NH-U14S, Motherboard ASUS Rampage V Extreme U3.1, RAM HyperX Savage Black Edition 16GB DDR4 3000 MHz, Graphic Card Gigabyte GeForce GTX 1080 8GB, Power supply Corsair RM Series 850W, Windows 10 64 bit.

  • Trespassers,


    Yes, Jet-Pack can indeed do magic with the TMD files. 8o


    I would also like to see a slower and longer takeoff run with a gradual increase in the rate of climb. I probably have more hours in the pattern in a Cessna 150/2 than most folks have total time, so I would also love to be able to reduce power downwind and make a nice leisurely and quiet gliding approach to a landing. I have very fond memories doing just that.


    Some friends of mine have been working on building several of these airports as an add on area for some time now. Maybe it all will come together soon so I can recreate those happy days and share them with the community.


    Thanks for your test flight comments.

  • One item that needs attention is the throttle creep (fast creep). I can't seem to fix a throttle setting by using either my Saitek x52 Pro or the 3D throttle on the panel of the Cessna.


    Whatever setting I choose, is immediately changed back to 100%.

  • Yes, Jet-Pack can indeed do magic with the TMD files. 8o

    I can take a look at it when I have the free time and feel like working then.


    For starters you can move the center of mass by changing the first component of the R0 vector of the Fuselage rigidbody.

    Keep reducing the first value in small steps until it doesn't feel nose heavy anymore.

  • Thank you Antoine,

    I am aware of the wrong flight dynamics and I have been spending the week-end trying to improve things.

    Now she climbs below 1000 fpm and keeps a more reasonable climb speed of 90~95 knots with flaps retracted (versus 2000 fpm @ 110kts). Max speed is now around 125kts (vs 140). Descent is still problematic, even worse. I have reduced the wing area (aerowing table) so now she floats less. I have to trim almost full nose up to keep a reasonable descent speed.

    There is still a lot of work and I'm far from being good in math and physics.

  • Yes, tuning a flight model is a lenghty iterative process. There are a few obvious parameters like engine power or displacement, prop size and pitch, where you can quite easily find an accurate value to fill in, but there are parameters like aerodynamic coefficients, COG or inertia moments that are trickier to setup without dedicated tools and some documentation.


    Good luck!

    Antoine

    Config : i7 6900K - 20MB currently set at 4.00GHz, Cooling Noctua NH-U14S, Motherboard ASUS Rampage V Extreme U3.1, RAM HyperX Savage Black Edition 16GB DDR4 3000 MHz, Graphic Card Gigabyte GeForce GTX 1080 8GB, Power supply Corsair RM Series 850W, Windows 10 64 bit.

  • Do you need the POH of a C152?

    X-Plane 11.3x / DCS 2.5.4 / P3Dv4.5 / Aerofly FS 2


    Win10-x64 | ASUS Z270E | Intel i7-7700K @4.5GHz | Corsair Vengeance LPX 32 GB DDR4 | 6TB SSD Samsung 850 Pro | ASUS GTX 1080 ROG STRIX 8GB DDR5X | TM Hotas Warthog | Saitek Combat Pedals | Oculus Rift S

  • Do you have multiple throttles assigned?

    Nope. It is only on the C152.

  • Nope. It is only on the C152.

    Could be that he use an input_default and not an input_lever... afaik the input_lever can handle multiple devices, the default can't, which is what I was asking if you have multiple ones assigned... But if you don't have multiple ones assigned then I don't know where that creeping could come from, I'd have to look into the code...

    Sure the copilot wasn't on by accident?

  • CoPilot could have been on. I’ll check that next time I fly. Thanks.


    Jan,


    It was the CoPilot doing its thing in the background. Thanks.