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My first flight in N509CT


FlyingMonkey

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Got my first time in my new CTSW today. My instructor gave the airplane a thorough once-over before we went up, and pronounced "you STOLE this airplane". That made me feel good. He did notice, however that the spinner to cowling gap was slightly smaller at the bottom, which he thinks may indicate it has a hard landing at one time. He said this is common, and when his has this issue they shimmed the motor mount with washers at his last annual. Here's a pic that is at an odd angle to see what I'm talking about:

 

IMG_20130727_105807_zps75ef050e.jpg

 

On preflight I noticed one of the exhaust springs was broken, but they were all safety wired as well and I already had some on order, so we didn't let that stop the flight.

 

We also think the prop may need some adjustment, as my CT with a three-blade Neuform does not seem to climb nearly as well as his with a two-blade Sensenich. Mine climbs in a much flatter attitude. It was getting about 550-600fpm at 1300lb-ish, and about 1000-1100fpm when he got out and dropped in to about 1100lb. Flat and level we saw about 5200rpm and 119kt. I know Roger says that should be 5600, but we were at 1900ft due to cloud cover and my usual cruise will probably be 3000-5000, so I'm not sure how that affects the calculus on that. I'm planning to go back up tomorrow and if the weather permits will climb higher.

 

The airplane handled great, no surprises, and took very little trimming to make it pretty much hands-off. Power off stalls broke straight ahead at 43-45 knots with zero flaps, pretty much right on book numbers.

 

My solo landings were a little disappointing. The first was total crap, a balloon and then dropped in in from a foot or two. The other two okay, but both left of the center line. I obviously need to be looking down the runway farther. In the end the instructor pronounced all three safe if not beautiful, and combined with our previous flights in his CT he pronounced me a CTSW pilot and released me into the wild.

 

If weather permits tomorrow will be more landing practice, and then next week some air work (stalls, cruise flight tests, etc) and some short hops to nearby airports.

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Hi Andy,

 

Usually a bounce in the CT comes from pumping the stick, hold it steady with a slight increase in back pressure and let it land. The balloon usually comes from trying to land before the plane is ready, just hold it off and let it land with a steady hand.

 

No link for the prop adjustment, but you can call me. It's a piece of cake and even a first timer should be able to do it in 45 min.

The gap at the spinner looks perfectly normal. Leave it alone, it isnt a perfect world. Without hesitation I would tell you you need to reduce the prop pitch by at least 2 degrees flatter. The low WOT rpm will only get worse the higher you go. I have adjusted maybe 100 or more LSA props in seven years and I believe I have the experience to fall back on. After you flatten it you will still need to go fly and test it for WOT flat and level at your average altitude. Sometimes a prop needs another .5 degree removed. Gaining the extra 400 rpm will make you think someone super charged your engine. These are critical rpms for climb, higher altitude cruise rpm, fuel economy and WOT speed. The first thing you should notice is compared to yeaterdays throttle setting in cruise yours will be throttled back to achieve the same speed.

 

Charlie Tango was in the same position about 6 years ago, but at his high field elevation and cruise altitude.

Come on ED, didn't I make a believer out of you when you said and I quote, " Woodstock comes alive". :)

 

The spring install is no big deal. Just safety wire it and I would use .041 size wire and not the thinner .032. Don't make it tight or it will break again. It should be a little loose. It is there to hold any pieces of a broken spring not hold the exhaust together. Make sure you apply the high temp silicone to the spring correctly.

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Roger,

 

I never had any doubt about the need to flatten my prop, for me the difference was more dramatic. All Andy needs to do is look at a Power/Torque chart and see how limited his power is at 5,200

 

IMHO Bounce is from rapid sink at contact, and is probably and indication of too much speed.

Balloon is from raising the nose before you are behind the power curve, it is surely a sign of too much speed.

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Hi Andy,

 

p.s.

 

If you do the prop in less than 30 min. Sandpiper will buy you dinner. LOL LOL

 

Always someone in the group thinks they should have been a comedian!! :P

 

Of course, Roger had to have the cowl off first, all the tools lined up, etc. :blush:

 

But, it is easy.

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You can bounce below stall speed. Just drop it in from a little too high especially with soft tires or yank the stick way back too fast and hard.

 

Rapid sink will do it, but pumping the stick like so many do will cause it too. An unsteady hand with too much back pressure at the wrong moment with a little extra speed will balloon you for sure. The speed doesn't cause the balloon, its too much sudden back movement on the stick. I have touched down way over flying speeds to show that doesn't cause ballooning or bouncing. Speed doesn't cause it, it is poor piloting, speed will just compound it. I can land at 80 knots and be very smooth and yes then you have speed to bleed on rollout, but so long as you don't do something dumb you just slow down.

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You can bounce below stall speed. Just drop it in from a little too high especially with soft tires or yank the stick way back too fast and hard.

 

Rapid sink will do it, but pumping the stick like so many do will cause it too. An unsteady hand with too much back pressure at the wrong moment with a little extra speed will balloon you for sure. The speed doesn't cause the balloon, its too much sudden back movement on the stick. I have touched down way over flying speeds to show that doesn't cause ballooning or bouncing. Speed doesn't cause it, it is poor piloting, speed will just compound it. I can land at 80 knots and be very smooth and yes then you have speed to bleed on rollout, but so long as you don't do something dumb you just slow down.

 

Sure you can bounce below stall speed but there is a big difference and that is you are done flying. Most bounces result in more flying and another landing or two, those are a sign of too much speed at touch down.

 

Speed + pitch = performance, you can't say speed doesn't cause ballooning. 'too much sudden back movement on the stick' only works if you are in front of the power curve so you can't blame that.

 

I never said that speed is the cause, I said that ballooning and bouncing and flying some more are indicators of too much speed. You can't balloon if you you are behind the power curve and you can't flare if you are in front of it.

 

There are different ways to achieve rapid sink which is needed to bounce. If the control inputs include 'pumping the stick' and result in rapid sink that doesn't mean that pumping the stick not rapid sink caused the bounce.

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Questions...

 

...is changing prop pitch something a pilot can do to his or her own S-LSA? I would think not.

 

...and does FD specify a pitch or acceptable pitch range?

 

Not nagging - just want to be sure everyone stays legal.

 

As far as the spinner/cowl clearance, when I noticed that on my Citabria it was worn engine mounts. Just adding spacers may not be the solution if that's the case.

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Just to clarify, my first landing was not a bounce. It was a slight balloon caused by being overly aggressive on pulling the stick back in the initial round out. Plane had enough speed to rise a little, then with the nose high speed decayed very fast and the plane plopped to the runway when the lift was lost. The was no bounce.

 

I knew it was about to happen, but I thought in might settle instead of dropping. After the fist bit of balloon I should have just gone around or added a touch of throttle to cushion the descent. No harm done, nothing bent, and I learned to be Johnny-on-the-spot with throttle next time.

 

I will say the smaller tires on my airplane are less forgiving than the tundras on the trainer I was previously using. I wish I had the $3000 for the full upgrade sitting around. Does anybody have a suggestion on the best pressure to run in the smaller tires?

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let me try again...

 

i thought the bounce could be a result of plane coming into ground effect. ever see a pelican cruising low over water? it's because ground effect makes for flying with less effort. suggest google 'ground effect'. if you're low on fuel coming in from gulf of mexico for example, flying low over water will reduce fuel burn. i think half a wingspan of altitude will do it. [might also make your mayday call unreadable]

 

w.r.t spinner uneven offset, this is found on almost every rotax powered a/c i've seen. "p-effect" is not what i really meant (yeah, drinking too much coffee b/f flight, p-effect) i meant to say "p-factor" which comes from assymetric prop wash on airframe; mostly makes for yaw. with such a low time airplane i doubt you have engine-mount issues

 

i don't know if FD provides protractor for neuform but if your gonna say 'flatten pitch" by so-many degrees might want to also specify radial distance (from backing plate?) that pitch is measured; i.e., where on prop to measure. no free lunch...changing prop pitch will change short-field performance as well as cruise

 

 

 

 

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You can measure angle on several places toward the prop tip. Anywhere that it's kinda flat. Maybe 8" from tip give or take. Pick the same spot on every blade. Place blade parallel to floor, measure blade angle. repeat for each blade.

 

There are protractors that clamp to the blade making this easy. You are not measuring to any manufacturers spec. You are measuring where each blade is in relation to level using the same spot on each blade when the blade is parallel to the ground.

 

If your RPM is too slow, take some of the pitch out. Otherwise add pitch. Then do a static run up. If you have 5100 or less, go fly. Carefully monitor RPM on climb and when level to make sure you don't overspeed. If your WOT level RPM is between 5500 and 5600 RPM at or near your favorite altitude, leave it alone. Otherwise it's back to the protractor.

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I never touched the pitch of my S-LSA Sky Arrow until I converted it to E-LSA.

 

Changing prop pitch is nowhere listed as maintenance or adjustment an owner can do. Since it requires tools, it's a far cry from a flight-adjustable trim*.

 

On top of that, my maintenance manual specified one and only one pitch setting for the prop: 13.5° at one specific prop station, IIRC.

 

It should not be a big deal, but any time you put a wrench on the airplane, that maintenance or adjustment should be specifically listed under 41.3 - otherwise it requires a certificated mechanic to at least sign it off.

 

Remember further that when you change the pitch on the prop, all your performance charts will be off from the factory setting: takeoff, cruise and climb performance, range, that sort of thing. As Roger has pointed out, even cooling may be affected.

 

Once converted to Experimental, virtually all these restrictions go away. Until then keep your eyes open to legalities to stay out of trouble.

 

*Even bending ground adjustable trim tabs is something a mechanic should technically do.

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