Cessna mods for the backcountry

Discussion in 'Flight Following' started by motoadve, Apr 4, 2021.

  1. motoadve

    motoadve Pre-takeoff checklist

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  2. Shepherd

    Shepherd En-Route

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    The PA-18 mod, with the additional fat tires mod.
     
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  3. luvflyin

    luvflyin Final Approach PoA Supporter

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    What propeller was that?
     
  4. NordicDave

    NordicDave Pattern Altitude PoA Supporter

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    Love my Robertson R/STOL kit where the ailerons are converted to flapperons. 34kt stall at max gross. Help with glass smooth landings.
     
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  5. motoadve

    motoadve Pre-takeoff checklist

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    MT propeller.
    Never flown with the Robertson, I think they dont make it anymore.
     
  6. denverpilot

    denverpilot Tied Down PoA Supporter

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    One of the competing STOL makers owns the STC and makes parts but won’t sell complete setups anymore AFAICT.
     
  7. Dana

    Dana Pattern Altitude

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    I didn't watch the video, but from the picture it seems the best backcountry mod would be to put the little wheel on the correct end? :D
     
  8. Matthew Rogers

    Matthew Rogers Line Up and Wait

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    When you put the little wheel in the back, the plane still want to fly in tricycle configuration. That’s why you guys seem to end up backwards in the grass on the side of the runway so often. That little wheel knows it should be up front and will get there eventually.
     
  9. NordicDave

    NordicDave Pattern Altitude PoA Supporter

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    The STC holder is now installing them again as new. https://skyway-mro.com/robertson-stol-high-lift-systems/

    There was a period of time here they were only selling parts post the ownership transition. This was based on a phone call with them about a year ago, not sure if it’s the latest.
     
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  10. denverpilot

    denverpilot Tied Down PoA Supporter

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    Neat! We had to buy a part once. So that was the last time we had any contact with them.
     
  11. Stewartb

    Stewartb Final Approach

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    Back country mods? Survival gear. Sat phone. Tool kit and knowledge of how to use it.

    Big tires, big motor, big prop. Those enhance capability without compromising performance in unfavorable winds. Wing extensions and similar STOL mods are fun when you can pick your weather but my stock wings allow me to go when other guys won’t. For those nice days? A slat wing Cub with 235hp is fun. ;)
     
  12. Silvaire

    Silvaire En-Route

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    There are at least a couple of PA-18 Supercubs out there that have had Cessna wings put on them.
     
  13. denverpilot

    denverpilot Tied Down PoA Supporter

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    Most go for small prop to keep it out of the rocks.

    I have no idea what that last blather means. I can’t think of any weather the STOL kit cares in the slightest about, or that would cancel a flight that a non-STOL aircraft could accomplish.

    Leave the flaps up, my wing is identical to stock, if there’s even a reason for needing that.

    Which, there isn’t.
     
  14. Stewartb

    Stewartb Final Approach

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    The only rock dings I get in my props comes from rocks being tossed from the tires. Length of prop doesn't make any difference on my planes. Humidity and surface composition make a huge difference for what sticks to the tires and gets thrown over the top. Probably not an issue for you nose dragger drivers, but in my memory of my own nose dragger I can't recall any prop ding issues.

    Come fly into a short narrow strip cut into tall tress with an obstructed approach in 40 mph winds crossing at 45*. High lift wing candy is not your friend. In my own life the high lift adds wouldn't make anything better but would make things much worse on the windy days. When getting over tall trees on short strips power and thrust are king. And buckle up tight for when the wind hits you at the treetops. A stock wing Skywagon should be able to safely operate in and out of 500-600' with most loads on most days. For shorter than that? I have a Cub with the ultimate wing candy and gobs of horsepower. And as fun as it is on a nice day? It's no fun at all on a rough day that ends with landing in winds diagonal to the strip.
     
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  15. denverpilot

    denverpilot Tied Down PoA Supporter

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    Man let me go get my hip waders. It’s getting kinda deep in here now.

    Don’t want high lift and high drag, don’t deploy it. Or just learn how to fly the airplane as configured.

    High lift and drag cause absolutely nothing toward any of those things other than the short part. It’ll fly just fine either way if you know how to fly it.

    (I would have added that it helps “obstructed” but most people know how to use a slip. Hell mine you can slip with all 40 degrees of flap if you want and it’s going to handle any obstruction better than anything but a freight elevator in that mode.)

    Methinks you regularly make wild claims that have no basis in aerodynamics.

    Now... if you said a whole bunch of people with high lift devices don’t actually know how to fly them to their full potential — and would eff up that approach...

    I’d have no argument with that.

    But the airplane doesn’t care about any of that stuff and the STOL kit doesn’t make it any more or less difficult — assuming you know how to actually fly the thing with the STOL kit on it correctly.

    Correctly includes understanding you have lower airflow over the rudder and prop thrust WILL be part of the round out and assist to use the rudder effectively. Counter-intuitive until you’ve practiced it.

    Have to understand your equipment. Just like any machinery operation. Most play with their STOL devices but don’t actually practice with them to be proficient at stuff you mentioned.

    Most get nervous using full control deflections required at low speeds, as a starter... all the way to the stops isn’t in their experience and it feels wrong at first.
     
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  16. Stewartb

    Stewartb Final Approach

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    My claims are observations and pireps. There’s a reason I never added WingX to my Cessna. There’s a reason I have extended wings with 9-1/2’ Fowler flaps and leading edge stats on my Cub.

    I have friends with RStol, friends with WingX, friends with Sportsman cuffs, even one with a Wren. Friends with stock Cubs, big motor Cubs, Carbon Cubs, slat wing Cubs. I have what I want for what I do, which is primarily what you guys call back country flying. I’ll stand by my comments. You’re welcome to have different opinions but that doesn’t make mine wrong.
     
  17. denverpilot

    denverpilot Tied Down PoA Supporter

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    Aerodynamics and physics make your assertions wrong. My opinions have nothing to do with it.
     
  18. Stewartb

    Stewartb Final Approach

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    Congrats on making your first post I could read without falling asleep. At least you have that going for you. Me? Still happy with what I said. When the strip's 4' wider than your gear and the wind's blowing across? Wing loading is my friend. For taking back off? Power loading is my friend. On nicer days? Nothing I've flown beats my Cub. landing at 20 mph is pretty darn cool.
     
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  19. denverpilot

    denverpilot Tied Down PoA Supporter

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    I’m super glad you’re happy with what you said even if it has no basis in physics or aerodynamics. Good for you.
     
  20. 455 Bravo Uniform

    455 Bravo Uniform En-Route

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    I kinda like it when two seasoned POA members go at it. It’s like watching 2 trophy bucks spar. Neither one is kilt, just fun to spectate. :D
     
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  21. 455 Bravo Uniform

    455 Bravo Uniform En-Route

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    And just so I contribute something - would a Peterson STOL (front mounted elevator canards, plus 260-300hp) fall into a different category because it pretty much retains the 182 wing loading? Or is there no “free lunch”?
     
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  22. denverpilot

    denverpilot Tied Down PoA Supporter

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    Now now you stop mentioning all that fancy math and science stuff! We all know anecdotes trump that stuff! LOL
     
  23. Wagondriver

    Wagondriver Pre-Flight

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    I didn't watch the video, but I got pretty much everything you can do to an old 180. The cuff DOESN'T hurt your abilities at all, it gives a bigger window in which to operate. You can take advantage of it or not, just like most improvements. Just because I have nearly 300hp doesn't mean that I need to firewall the throttle, but it sure is nice when you need to.
     
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  24. NordicDave

    NordicDave Pattern Altitude PoA Supporter

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    Can't to this with a standard 182 - Go R/STOL

    1400' Book take-off over 50' obstacle, reduces to 825' with Robertson STOL

    Screen Shot 2021-04-08 at 6.35.49 PM.png
     
    Last edited: Apr 8, 2021
  25. Stewartb

    Stewartb Final Approach

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    I did 900’ over 100’ trees at gross in my old Hawk XP with wife and daughter on board. My 180 was an improvement. When I put the 520 and 86” 3-blade on it it got even better. I don’t do this stuff occasionally. It’s my life. I’ll make a video when the snow’s gone. You won’t bring that 182 where my Cub will go. And I’ll bet you won’t take that 182 where my 180 goes. Give me a few minutes to put skis on and I’ll school you good. ;)
     
    Last edited: Apr 8, 2021
  26. Dana

    Dana Pattern Altitude

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    Anything that reduces wing loading and/or stall speed will reduce the amount of crosswind or gusts that can be safely handled. Flaps or other deployable high lift devices can be retracted, yes, but wing extensions or VGs can't.

    Everything is a compromise.
     
  27. idahoflier

    idahoflier Cleared for Takeoff

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    Nice, capable aircraft! That said, it seems like the better path would be to buy a C180 or C185 and call it good...
     
  28. Matthew Rogers

    Matthew Rogers Line Up and Wait

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    I don’t see how VGs could make a plane handle worse in gusts or cross winds. All they do is keep the airflow stuck to the wing at high angles of attack. Please explain - as VGs don’t affect wing loading or much of anything other than lowering stall speed, which would seem to help in gusty conditions as airspeed increases and decreases with gusts.
     
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  29. 455 Bravo Uniform

    455 Bravo Uniform En-Route

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    And what about stall fences?
     
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  30. idahoflier

    idahoflier Cleared for Takeoff

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    I was thinking that @Dana was speaking in the context of flying the approach at those lower airspeeds afforded by the VG's?
     
  31. Matthew Rogers

    Matthew Rogers Line Up and Wait

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    Or is it that you can’t actually touch down if the wing is still flying? Consider if your wing flies at 25 mph and the winds are 30 mph down the runway. You can’t even untie from the parking spot without the aircraft wanting to fly away, right? In that case you could not land the plane until the plane was going -5 mph backwards. Or you land with a 30 mph tailwind (which isn’t so bad as you are only going down the runway at 55 mph).
     
  32. idahoflier

    idahoflier Cleared for Takeoff

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    If that's the performance I can expect out of VG's, I'm buying some! ;-)
     
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  33. Matthew Rogers

    Matthew Rogers Line Up and Wait

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    Haha, it was an example, but some highly modified Cubs or the Highlander, may have stall speeds that low.

    If I could lower the stall speed of my stock C150 to 25 mph for $600 in VGs I would be all over it too. Even with that it is hard not to want a little extra safety margin for only $600.
     
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  34. Dana

    Dana Pattern Altitude

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    :yeahthat:
    The winds you can handle are proportional to your stall speed. The lower the stall speed, the less wind (cross or otherwise) you can handle.

    It's why airliners fly in winds that keep single engine Cessnas on the ground, and Cessnas fly in winds that keep ultralights on the ground.
     
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  35. Matthew Rogers

    Matthew Rogers Line Up and Wait

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    But does that still apply to VGs? The airflow over a wing at a level attitude (i.e. a tricycle gear airplane rolling on a runway) is unaffected by the VGs, which only affect airflow when at high AOA. So after landing, the stock wing and the wing with VGs should have no difference in their characteristics.

    You may have to keep a higher airspeed (lower AOA, all things considered) than the VGs would ultimately allow you to fly (at very high AoA) when landing in high winds, but at those higher airspeeds, the AOA is probably out of the range of where the VGs have any affect as well. So say you could have an approach speed of 35 mph with VGs and stall fences, but if you fly the approach at a "stock" 55 mph, what difference would there be when the airplane is finally on the ground?
     
  36. Matthew Rogers

    Matthew Rogers Line Up and Wait

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    He says he has landed his highlander in winds blowing over 30. It has a stall speed of 36 mph.
     
  37. idahoflier

    idahoflier Cleared for Takeoff

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    I think it has more to do with rudder authority than stall speed. But assuming you are correct, retracting flaps can effectively negate any advantage (or I guess in this case disadvantage) VG's provide...
     
  38. Dana

    Dana Pattern Altitude

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    Mmmm... maybe. If you drive it onto the ground above stall speed, then yes, I guess VGs make no difference. But for a full stall landing, that stall speed will be lower, more chance for the wind to get you. But I've never flown a plane with VGs. I guess how the plane behaves in windy conditions depends on just what STOL mods you have.
     
  39. AlphaMike

    AlphaMike Pre-takeoff checklist

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    I’ve got the sportsman STOL with micro VGs. From my experience I don’t really see any stall speed difference with VGs. But the controls are much better at lower speeds with the VGs. I haven’t seen any negatives regarding the sportsman STOL or VGs. Stall speed is lower, climb rate is higher, and better slow speed control.
     
  40. denverpilot

    denverpilot Tied Down PoA Supporter

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    Incorrect. Controllability has nothing to do with stall speed. It has to do with the effectiveness of flight controls.

    You can make aircraft with flight controls that are effective at low speeds. They exist. You can even make aircraft with thrust vectoring if we’re talking math and physics.

    Stall speed has absolutely nothing to do with controllability UNLESS you didn’t pay attention to the control authority when modifying the aircraft.

    Are we taking aerodynamics or are we talking about the market of badly designed “STOL” strap ons that focus on only one thing?

    Because most of the aerodynamic statements are false in this thread. They apply only to very specific mods that aren’t being mentioned and without that accuracy...