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Richard Sennett

Takeoff problems

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I have many Carenado aircraft, great stuff but never had a problem lifting any of them of the ground the skymaster will not takeoff easily it just goes up a little bit and then falls to the ground again flaps - trim nothing helps any help would be appreciated, thank you. Rich

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Have you tried a bit of aileron? Sometimes getting one wheel off the deck will help to unstick an aircraft that seems reluctant to fly since it puts on a bit more ground effect, although you might have to be ready to kick on a little bit of rudder since that effect will be on one wing only, and you'll have a bit more drag from the wheel still on the ground. But be somewhat cautious with this trick at lowish speeds (as in 'watch out for excessive yaw and even adverse yaw' especially on aircraft with a long wingspan, not as in 'only use a bit of stick') since your ailerons will of course be less effective at take off speeds and you might initially need a fair bit of input to make it happen. I suspect it's not a technique most ab-initio instructors would advocate, and I probably wouldn't try it on a check ride either LOL, but it does work (both in the sim and in real life, especially on taildraggers). Al

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Guest bstolle

With the default loadout you don't need any trim or flaps for take-off. Suggest to check the joystick calibration.The idea with the aileron input to lift one wheel sounds very strange to me. Both in the sim and IRL. How should this influence groundeffect?

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As you probably know if you've ever done any formation flying, the turbulent drag-inducing wake from an aircraft spills back and down behind the aircraft, which is why you get bounced around when flying below and behind another aircraft, rather than when you are directly behind it. This is one of the chief reasons why ground effect increases lift, because when a wing gets close to the ground, it cannot properly form a wingtip vortex because the ground breaks up the airflow trailing off the wing, which means there is less induced drag (this is exactly what winglets do - smooth out the wingtip vortices - and as you will know, winglet-equipped aeroplanes have a shorter take off roll). Thus there is even less induced drag when you put some roll on the aircraft and stick a wing nearer to the deck, not much, but the increase is there. Since there is also less thrust required to maintain speed when there is less induced drag, the aircraft will accelerate more for the same power setting, so you'll reach flying speed quicker too, and it will also require a lower angle of attack to generate lift, which is another bonus you gain. All of these things combine to help unstick an aircraft, and though each effect is fairly small, they combine to be quite a noticeable effect and you will find that because this is so, the technique, as strange as it may seem, actually works. You can demonstrate this for yourself in the real world if you fly several aircraft types with a similar NACA profiles, or if you fly gliders using winch launches: Low wing monoplanes get off the deck sooner than high wing monoplanes with the same wing profile, since they are effectively in more ground effect than their high wing counterparts. If you fly gliders, try this: hold the aircraft down a foot or so above the airfield on a winch launch, where you'll be in some seriously decent ground effect since gliders have a big wingspan. Doing that reduces the effort the winch is exerting because of the lack of induced drag it has to overcome, so when you reach the speed where you pull up for the climb, you'll find the winch really gives it some power and you can go really steep for quite a few seconds without sapping the power off the winch, so you'll get a higher launch. Do that right and you'll get another 300 feet off the launch of an average glider winch. You can sort of do that in a powered aircraft too by the way, i.e. hold it just off the deck after lift off and you will pick up speed quicker, since you'll have less induced drag, although this is a lot less risky to do in a glider on a winch, since there is no prop to strike the ground when holding the aircraft just off the deck. If you fly a lot for real, you tend to suss these sneaky tricks out. wink.png Al

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Well its not fixed, have to check yoke calibration, thankd for the heads up, just got it working correctly with my quadrant and yoke with the NGX, now I have to see if I can get things right for both heavies and GA aircraft, now thats quite a post Al wow, thanks Guys. Oh did a reinstall and patch no joy fyi

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Guest bstolle
1. (this is exactly what winglets do - smooth out the wingtip vortices - and as you will know, winglet-equipped aeroplanes have a shorter take off roll).2. Thus there is even less induced drag when you put some roll on the aircraft and stick a wing nearer to the deck, not much, but the increase is there.3. Since there is also less thrust required to maintain speed when there is less induced drag, the aircraft will accelerate more for the same power setting,
1. Didn't know that and I doubt it. IRL the effect is negliable or not there at all because the performance tables I've seen don't show any difference in take-roll distance for the same plane with and without winglets. Winglets reduce induce drag, but whatever thing you glue onto a wing which sticks into the the airflow adds weight and increases drag. 2. You are contradicting yourself! If you put 'one wing closer to the deck' you lift the other one away from the deck and hence reduce ground effect on the other side. By banking the plane you loose a part of the vertical lift component plus the fact that you have to add rudder to keep the direction, which adds drag. You also have to overcome the resistance to tilt the plane to one side, thereby increasing the friction of the wheel you are putting the additional load on. The additional aileron deflection adds drag as well. The net effect of banking the plane during the take off roll is definitely a total drag increase, a performance loss I don't know why this should make unstick easier but this 'technique' for sure adds to controllability difficulties during the take off run. 3. During the take off run with an AoA of approximately 0, I'd say that the weight and drag increase of the winglet at least cancels out the better acceleration, (if it's there at all).

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Well, i have the same problem right now.Purchased the Skymaster yesterday and it simply won't fly into the air.If you set flaps 33% (which is position 1 for them) and trim it to 6° you will eat up near to all the runway before reaching 95 kts GS before it lifts off.And then you can't keep it in the air. It will always drop the nose and ram into the ground until you fly it near stall (or better said not stall it 1 out of 10 times) to keep it flying level or climbing with 50ft/min. Same goes for climb once you get it flying...it won't climb.Forget about 500ft/min like other Cessna do..... i think this is a bug. I really can not imagine, why a plane that isn'T capable of climbing with 100% fuel without load.Even in the late 1960th such a plane wouldn't be used anyway. I hope for Carenado to put out a patch real soon.

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Guest bstolle

There's definitely no patch for that user problem needed. Do you really think that Carenado would release a plane that doesn't even take off?Even at maximum take off weight and the trim at neutral I can lift then nose wheel at 60kts from the runway with and without flaps.The trimmed speed with neutral trim is 100kts.Just tested and the only way I can get her to 'take off' at 95kts is if the autopilot has been engaged!!!Also the 50ft/min rate of climb with full up elevator is only possible if you are fighting the autopilot.Suggest to either recheck your joystick calibration or if the autopilot is state. Another thing, do you have a default plane e.g. the Trike or 172 in the menu screen when loading FSX?This is essential to correctly initialize add-on planes to load a default plane first

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There's definitely no patch for that user problem needed. Do you really think that Carenado would release a plane that doesn't even take off?Even at maximum take off weight and the trim at neutral I can lift then nose wheel at 60kts from the runway with and without flaps.The trimmed speed with neutral trim is 100kts.Just tested and the only way I can get her to 'take off' at 95kts is if the autopilot has been engaged!!!Also the 50ft/min rate of climb with full up elevator is only possible if you are fighting the autopilot.Suggest to either recheck your joystick calibration or if the autopilot is state. Another thing, do you have a default plane e.g. the Trike or 172 in the menu screen when loading FSX?This is essential to correctly initialize add-on planes to load a default plane first
So, let's just suggest, i am way too stupid, then.I would like you to take some of your minutes and please explain to me, what i would be doing if i were to fight the Autopilot. Maybe that's it, i would thank you very very much if i could fly the plane without fighting it (seems, i am loosing 9 out of ten times, anyway).

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Guest bstolle

If the autopilot is ON, you have almost no pitch control with the joystick and in that case she will lift at around 95kts if you keep pulling the stick fully aft and she will just barely climb at about 50ft/min.Have you tried toggling the AP on and off with the appropriate key stroke ?What does the AP master switch (and the tooltip) below the throttle quadrant indicate?

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Ok, thank you. No, at Takeoff the AP is OFFI turn on the FD and programm the GPS to a course with some waypoints. I do however point the Heading bug towards the runway and point the HSI needle towards the next waypoint.But AP is OFF till some hight is gained. Then i turn on AP and the plane immediately turns towards the course but also sticks the nose down rather steep putting the plane into the ground if i do not switch OFF the AP and pull to near stall. This happens 9 out of ten times.NO, ALT HOLD isn't selected yet. What i do once i managed to get into the air and the AP won't kill us anymore isFD ONAP ONNAV ON And then i change the Pitch on the lower FD panel to gain some hight. That's where i can select any pitch to rather stall the plane but gaining no hight at all or climbing at 50ft/sec.It simply won't climb but pitch till it stalls. It almost does the Cobra manuever Su 37 could do but still flies level without ALT HOLD selected.In other planes i flew, i could select a hight, ARM it and when reaching it, the AP beeps, levels the plane out and holds that hight.In the Skymaster i couldn't find such a mechanism. so i do not really know, how to selcet a hight or how to climb to a descent hight without stalling or hitting the mountains.

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She behaving fine here, since day1, so we may have to look into the current setup of yours.Can you take some screenshots when this happens, Mario?Maybe go to pause and then post a screen of the complete panel and maybe also look what the tooltip on the trim wheel tells you, and then tell us. smile.png If you do this with a state before enabling the AP and after, it would be perfect.

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Well I woul have to say I still have problems also trim the hec out of it still it dives to the ground will not stay airborne, fustrating anymore ideas I would luv to hear them, I have calibrated the yoke still no good, thanks Guys.

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well. unplug your yoke altogether or just disable it... and try to fly with keyboard or go into mouse yoke mode and try that... or hook up a cheap/another joystick... try something different... to make sure its not your yoke.

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This may sound silly, but I hit CTRL+F4 before each and every flight in FSX. This ensures that the system's prop pitch is fully set. I have heard of instances where even setting prop pitch to full on [VC or 2D] panel or on Saitek did not do the trick *unless and until* FSX system prop pitch was fully set ( ctrl+f4) beforehand. Make sense? Maybe not. Does it work? You bet.

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