SLM AIRWAYS

My Feedback: (3)

I just got a new Avistar, I was wondering if I added flaps onto it if it would make a better landing. I will be using a Thunder Tiger Pro 46, which makes the plane come in a little faster. At my park the runway isnt as long as others Ive heard about. Thanks everyone.

Landon[8D]

FHHuber

Actually... the TT Pro does not make the Avstar need a faster landing speed.... using the wrong prop may makethe plane retain flying speed even with the engine at idle and cause you to continuously overshoot the runway.

Flaps won't really help much on the Avistar. More work than they are worth. Flaperons would be a VERY bad idea if you are having problems with it needing to land fast.... you'd just make the aircraft easier to stall on final, and the stall would be more violent. (more likely to result in a spin... very bad on final approach.)

If you are using a 10X7 (which is commonly recommended for a .46 on the Avistar... try a 11X5 or even a 12 X 4. you will be suprized (and happy) with the result I am sure.

*********

Runway length required for the Avistar is abot 150 ft and then you need about 18 ft for every 10 ft of climb to clear obsticals. You can (with practice) do a nose-high power-on descent for short field landings where you chop power just as the wheels touch and have a steeper descent angle than the models's normal climb angle.

If you are not capable of that type descent and the glide slope (with the lower pitch propeller) won't let you easilly make the landings, you need to fly somewhere else while you build your skills. Always match your flying site to the aircraft and your skill level.

Geistware

My Feedback: (16)

NO, I would not add flaps to the avistar and it will not improve your landings.
Burning fuel is the only way to do this on a trainer.

dr_wogz

My Feedback: (3)

What they are saying is go with a lower pitch prop (the second number in the prop size...)

If you are using a 10-7, go to a 10-6 or a 10-5 (11-5 or a 11-4 maybe as well) check the engine manual, and see what is reccomended as 'low pitch'

DTB

My Feedback: (15)

I have been training a new pilot at my field on a NEXTSTAR that came with the airbrakes. These allowed the plane to land much more stable, but hindered normal level flight. I flew it this way the first time with the new student, but decided since he wouldn't be landing soon, I would take them off so that the plane would fly better without them while he was training how to fly level and make turns. The airbrakes (flaps) really slowed the plane down and made it much more stable than not using the airbrake. Another guy that I have helped actually has three servos in the wing and has cut the ailerons to make two flaps and two ailerons. This thing floats forever at a crawl.

I think if you set up flaperons it would help or put three servos in also the way the Nextstar can be done would help out with the landings. However, the setup would not be worth the work on the avistar unless you plan on flying it for a while, but chances are you will move on to another type of plane. On windy days though, I don't use flaps on my planes.

Al Stein

It sounds like runway length is a problem, so flattening out (i.e. lengthening) the glide may not be real helpful in this case.

MikeMc

Being that we're way beyond beginners we just spent all day Saturday experimenting with my buddy's Avistar. Flapperons make a HUGE difference in glide angle, and minimum landing speed with NO loss of control. We had landing and take off in less than 30 to 40 feet with about 5mph headwind with 40 - 45 deg down flapperons. I was even temped to run out and catch it on a few low/slow fly-bys (no I didn't).

I agree lower pitch/idle might be a better solution but the question was about flaps.

2 extra experiments...
- 4" x 4" speed brakes that come out 90 degrees on both sides of the fuse will slow it down too... a lot but block the horizontal stab for moderate loss of control.
- Replaced the flapperons (stock ailerons) with double the cord ailerons resulted in even more slow speed fun.

bassmanh

My Feedback: (5)

slm,

just remember the K.I.S.S. princeaple keep it simple stu... well you know the rest


anyway while learning the best thing you can do is keep as easy as possible until you have been flying for awhile.

as stated putting gas through the carb is the best thing you can do to learn to land and fly better.


bassman

FHHuber

Flaperons with an inexperienced pilot are a crash waiting to happen.

sure... someone that knows how to deal with the function can get away with it. I would not have a problem flying the Avistar with flaperons and playing around at low speeds. A beginner would be 99% likely to pile the thing into the dirt due to a stall-spin when trying to get a lower landing speed by using flaperons.

If you had to ask if they would help... you don't have the flying experience to deal with using them, and you will wreck the airplane.

We've got to remember... these are beginners asking for what will work best to help them LEARN to fly. Not experienced guys asking how to fly specific 3D maneuvers. (like the waterfall which the Avisatar can do with Flaperons)

MikeMc

Hence the high AOA power-on landing instructions above.

Chris-_-Memphis

My Feedback: (3)

i have the same setup.. slows like a baby... its the runway..




i love the avistar w/ a TT pro 46

Dukester

My Feedback: (31)

Thats funny, there's 3 or 4 posts related to Avistar and/or flaps going right now. I'll add my 2 cents here also. While I don't usually disagree with FH's comments, I will say that based on my observed experience with my Avistar the danger of stall spins is pretty low. i use about 30 or 40% throw max on my flaperons and you have to be moving very SLOW to stall the dang thing. I would say go for the flaperons and just start with small settings of 15 to 20% throw to get a feel for it, then move them up. Also, if you use slightly smaller servos (I used HS-81s) they will simply fit right into the slot for the original servo widthwise and you just have to shim them up a bit for length. This way you can always change back to single aileron servo later if you like.

On mine I have the stock 40 LA that I got on it when I bought it from the guy who tried to teach himself to fly (ok thats a whole other thread ). With the 40LA and a 10-6 prop a med-low idle floats it in quite nicely with no tendency to stall with 30% flaperons. I've done several dead sticks also and the flaperons do appear to make a noticeable difference in the glide angle.

Duke

vagent

Re flapperons on Avistar -- I made the mod on mine -- however have trouble getting the "amount of control surface movement" set up. I have a computerized radio (JR421EX) which provides flapperon control, however the flapperon and aileron movement on opposite sides cannot be set equal unless I set the "travel adjustment" for ailerons to 100%. This results because the gear (5th channel) is used to set the amount of flapperon movement and the aileron travel adjustment only affects one aileron. If any travel adjustment on the ailerons other than 100% is used, the result is that one aileron moves more than the other when the aileron stick is moved, and one flapperon moves more than the other when flapperons are activated. I started flying the Avistar at +-70% travel adjustment on ailerons (which gave me mfg recommended movement) and have gradually moved up to 80%, trying to get up to 100% aileron travel adjustment so I can try the flapperons. (Want to make sure I can handle the amount of aileron control surface movement I'm going to get at 100% of travel) And, yes, in conjunction with adding travel I have moved the position of the control rod in the servo arm to compensate.

I have concluded that this is a restriction of the radio (bottom of the line computerized radio), but if someone knows of a way around it, please advise.

Dukester

My Feedback: (31)

Vagent,

I can't say about the JR radio, but my Hitec flash5X has the same kind of setup Ch1 and 5 for flaperons. On mine I have to adjust the ch1 and the ch5 endpoints as they each affect a different servo. Once I get the endpoints tweaked so that the throws are the same for ailerons, then I just set the flaperon settings as a percent of current throw which affects both servos equally.
Hope this helps some.

Duke


edited for typing dumb-thumb....

DOH_Blk_Adder

wiht a trike as long as all three have touched down cant you apply forward stick pushing that nose wheen into the ground and addind more drag or it that a bad idea

Askalon

My Feedback: (1)

well, if your nose wheel is not tall enough, you could do a prop strike into what ever surface your landing on and then there is the possibility of a flip, but that is only my opinion.