I've got and am assembling my Phoenix Super Decathlon, waiting for a bigger fuel tank and engine mount - will maiden next weekend. what do I need to know about this plane? It has a really short tail, and I've heard something about torque rolls. I've also heard something about flying the tail, but if that just means keeping it straight and not nosing it over I should be all set. I' super excited to fly this plane; I'm pretty ready for it and am eager to hear your suggestions.

I also want to thank everyone in this forum. Im about to maiden my third plane and am training for my second pattern meet in only 2.5 months of flying. I owe it all to you for your experience and advice; I listened and took it to heart, and to the field. Thank you.

joe "Garfield" Marri

http://www.rcuniverse.com/forum/m_36..._1/key_/tm.htm

Slap a 12" on a .46 or bigger, it'll hang.

Perhaps instead of torque rolls you meant ground loops?

Learning to take off with it will probably be the biggest hurdle; It is more short coupled than "trainer" type conventional geared aircraft. The key is to get enough airflow over the rudder before you need to use it to make large corrections. I usually start the takeoff roll with full "up" elevator to keep the tailwheel planted firmly on the ground. The rudder isn't effective yet, so I need the tailwheel to "grip" the ground for steering. As I slowly increase power I slowly remove the elevator in one smooth motion. Eventually the tail will come off the ground, but by now you have enough airspeed to where the rudder will be effective. As the airplane gains speed you will be able to remove some of the right rudder you had inputted to keep the airplane tracking straight. As it gains flying speed, carefully pull up on the elevator to lift her off. Keep the climbout nice and shallow (20 degrees) to avoid a stall. Get her up high, trim, and feel it out. Many beginning pilots make the mistake of trying to trim the airplane right after it leaves the ground. They aren't used to needing trim and panic when they need input just to keep it straight and level. If your training was good you shouldn't have this problem anyway, but it's just something to keep in mind. When you're taking off close to the ground the idea is simply to keep roll and pitch deviations to a minimum. Only after you gain altitude should you take your fingers off those sticks to quickly grab the trims. I know this was a lot of information, so don't worry about it all. Just pick out some of the important stuff out of this paragraph of bull puckies and remember it.

Mine flew a lot like a Cub, but wasn't nearly the floater that a Cub is, and the stall break is more pronounced and took a bit longer to recover from (both from the difference in performance of a semisymmetric vs a flat bottom wing) . It is also more responsive in yaw due to shorter tail moment, and the roll rate is much, much faster and more linear than a Cub. All that said, I felt it was relatively easy to fly, it still requires rudder on takeoff to stay straight, but I don't try to pin the tail using "up" on the takeoff roll. I keep the tail pinned during taxi, but as soon as I throttle up for the takeoff roll, I release the elevator and let the tail rise when it's ready. Like Nathan said, just a touch on the elevator, let the plane fly itself off the ground, gain altitude slowly enough to allow the plane to gain airspeed in the climb. An Extra 300 it ain't.

It will likely be a bit of a handful on the ground. I have seen them get really squirrelly. It will also stall easier than a trainer or even many sport planes. It's definitely not a 3D type plane but it IS a high wing aerobatic plane. Not impossible to fly by any means but just not as forgiving as some others. Just keep the bad tendencies in mind and try to avoid them and it will fly fine.

Bah! In the scheme of things, the Decathlon is a piece of cake. You'll do fine.

i like the title how do i fly this plane? lol

yeah I'm not too concerned, but better to be proactive than reactive.

the torque roll thing - i heard that if you are going to abort a landing you have to be careful of torque rolls, not sure why, but i guess you're supposed to ease into the throttle, which is a good habit I picked up anyway to avoid problems with the engine as it's running closer to idle during approach.

Ahh, here's where the confusion lies. Technically, a torque roll is a 3D maneuver. What you are referencing is called asymmetric propeller loading. Asymmetric propeller loading (p-factor) is most pronounced when the airplane is flying at a slow airspeed, high angle of attack, and high power (like on a go-around). Take a spare propeller and hold it with the blades making a horizontal line. Imagine it's installed on your airplane and look at it from the side. Now tip the prop up like the airplane is climbing. Look carefully at both sides of the prop. What you'll find is that the right hand (descending) blade has a higher angle of attack than the left (ascending) blade. This means that the right blade is "grabbing" more air as it spins. This, in turn, enhances the thrust on the right side. If you have more thrust coming from the right side than the left the airplane will yaw to the left. This is exactly what you experience - the model will yaw left when you pour on the power in this slow, high angle of attack, maneuver. This is corrected with right rudder and NOT aileron.

Keep in mind that there are many other reasons your airplane yaws to the left, this is just the most applicaple effect given the circumstances of your example.

So the plane would yaw rather than roll? I thought what I heard is that the plane will roll if you nail the throttle to abort a landing, and even if you try to take off too quickly.

Anyway, thanks for the explanation, makes sense.

Yes, it may roll as well. In this instance, a roll would likely be caused by an uncoordinated stall. This is the dreaded stall/spin accident. Here's what happens:

You abort and pull up. You forget to add power and the airplane begins to stall. As this happens, you use the ailerons to bank right slightly. When you bank right the left aileron lowers and the right rises. This also means that the left side of the wing has a higher AOA than the right side. Let's apply this information to our situation here. You've now essentially stalled the left side of the wing more than the right side. Guess what happens, despite your command to bank right the airplane will dip left. In a panic you increase the amount of right aileron. What happens? Your airplane dips left even more! By this time it's too late because you are low to the ground and your beloved airplane cartwheels into the ground. You've essentially entered into a spin. It just can't become a fully developed spin since the airplane hits the ground beforehand. This is another reason why we use the rudder to correct for these things.

Again, the Decathlon isn't going to attack you unless you screw up pretty badly, so don't worry too much. Despite it not being a trainer and being aerobatic, it's still a relatively forgiving airplane.

It is possible to torgue roll an aircraft taking off or landing if the power is applied suddenly. This applies to full scale planes also. It requires a plane with an excess of power but it can and does happen. It can roll just as you thought. Planes powered within more normal hp will yaw but you can torque roll one with enough power. The torque roll predates 3D flying. One of the most wicked torque roll in the full scale area is the Douglas Skyraider. Somewhere I have a Navy photo of one torque rolling over the deck of a carrier after a waive off.

You are correct, but the torque roll is simply a byproduct of the aforementioned events, plus a few extras I have not touched on.

Thanks again.

Today I jumped on a sim for the first time since I started flying at my instructors house. It was funny because I realized how much I use my left thumb, where 2 mos ago on my sim I didn't use it at all. It's ALMOST second nature, but still over/under correcting a bit with the rudder, but doing well with it.

The rudder...LOL...Somebody has a signature line that sums it up pretty well. I don't know who it is, but I smile every time I see it..

"Wrong rudder is the most powerful force in the world"....or words to that effect...

LLD