hi everyone! i just purchased the great planes giles .46 kit. i taught myself to fly with an electric foam trainer, then a sturdy birdy 2, and i am now flying a 4* 40 with a TT .46 PRO on it. i can fly the 4* without any problems on max throws. in fact, i prefer the high rates even for landing as i am used to it.. low rates feel very uncomforatable to me. i want to build this giles with a .91 four stroke and fly it in the spring. i have read about it, and i can't tell what i should expect. is this thing just going to fall out of the sky if i back off the throttle for a moment? unrecoverable spins? i have never ever had a problem like that with the 4*. is this an acceptable 3rd plane? should i use a submicro servo for throttle and go nuts on trying to build it as light as possible? and what is all this about the plane snapping? i flew a trainer. i am flying a "second airplane." is the giles not a "third airplane"? i hope it is, because i really like the looks of it, and among the critisisms, i have read that many are quite fond of how it flys.

The Giles is fine as long as you keep the speed up when landing, BUT it is one of the worst models around (especially when it's on the small size like a 40 size) for snapping when you don't want it to.

It will slow speed snap when you apply too much elevator and will even snap when on a fast downline if you use too much elevator to pull out of the dive. In fact, I would recommend you spend the first few flights taking extreme care to adjust the elevator throws so that you don't accidentally apply the amount that will induce a snap. Fly high and try a tight loop, and reset the throws so that maximum elevator doesn't make it snap out at the top or bottom of the loop.

Good luck!

-David C.

well, i do use up to 50% expo so im sure that will help. im also not one to jerk the controls in any direction with an unfamiliar model near the ground.

on the subject of bad behavior, will someone exlain uncontolable spins? i have never seen this happen. when people say this, are they refering to being at a low altitude when it happens? 3 mistakes high, can't any model jsut be flown out of a manuver?

It is a flat spin that is sometimes hard to get out of. A rearward center of gravity location makes it easier to get into a flat spin and harder to recover.
Normal spins recover almost instantly when you quit pulling back on the elevator. To get out of a flat spin, you have to use rudder opposite of the spin direction, aileron with the spin direction, and down elevator. If you are in a inverted flat spin, you have to remember that rudder and elevator are reversed.

well, then i should not encounter a dangerous flat spin as i am learning to fly the giles, since i will keep the cg at the recommended spot for starting out. i have tried flat spins with my four star, but i think the cg is still to far forward.

Some airplane designs will not flat spin for love or money. A long wingspan and a short tail and small verticle fin i.e. WWI scale models, Cubs, etc. are most likely to flat spin.
When transitioning from a flat spin to a normal spin, the spin rate will speed up due to conservation of agular momentum, the same reason an ice skater's spin speeds up when they pull their arms in.
A search on the subject of flat spins will probably yield a lot more info on the physics involved somewhere in the aerodynamics forum.

im mainly interested in the question of "am i building a plane that just falls out of the sky for no reason?"

these forums are strange, i don't deny that they are very helpful in trying to do difficult, new things, but on the other hand, you could read yourself into a mental cage with all the different opinions out there.

OK, as a simple answer to the question "am i building a plane that just falls out of the sky for no reason?" the answer is . . . ready? . . . .

No.


-David C.

I think that what you really have to worry about on a plane like this is a surprise snap roll if you pull back on the stick too much. If you are three mistakes high, no problem, it will recover almost immediately when you let go of the controls. Even if you are only one mistake high, it's no problem, just don't make a second mistake. The unintended snap roll is deadly when you are zero mistakes high and slowing down to make a landing.
If the plane is a little nose heavy and the elevator has limited travel, the plane will be a lot less likely to tip stall and snap roll on you. Use low rates for landing.
If you really want to get fancy, you can build the plane with flaps that lower and ailerons that reflex upwards when the flaps are lowered. In this configuration, the wing effectively has washout, which prevents tip stalls, and lots of drag, a good thing when you are trying to land a plane that is a lot cleaner aerodynamically than the typical trainer.

thanks for the insight, guys.

i am chopping one bay of each wing tip of my four star, so it will be flying a bit faster to practice all winter. i was out flying it today, thinking about how a faster plane will be. i was stalling the fourstar, and observing it's tendencies. with reduced throttle and a 30 degree angle climb, it stalls very predictably, and i am not afraid to fly it low right on the edge of stall. i assume with this giles, it will jst be a matter of flying it high up, conservative cg, low rates to start.. and just observing it's reaction to stall. now, the snapping will be new, and i will be aware of that and make sure to get used to it up high.

i am just excited about flying something so advanced. i have crashed freshly built planes, and i want to take every possible precaution to avoid it this time.

One further thought..

It's worth getting to know the rudder so that you instinctively use it if you suspect that the wing has stalled and a tip stall is imminent.

As a tip stall approaches (say, on landing) there's a real possibility that the ailerons will work 'backwards' as part of the wing has stalled. The rudder almost never stalls, so that should be used to correct roll.

If, say, the left wing drops when the wing is nearly stalled, and you apply right aileron, the extra drag you are adding on the left wing (more lift always equals more drag) will make it 'dig in' more and thus not lift the left wing to correct the roll, but make it drop even more and it flips over onto its back.

-David C.

i'll keep that in mind also. i do use the rudder pretty often on the four star.. i find rudder input can make turns quicker than just ailerons, and for stall turns.. of course.

unrelated to flying, but, i'd rather not start a new thread..

is there any reason that i should not use a micro servo for the throttle on this airplane? if there isn't a good reason, i am going to, for weight savings.

An excellent idea, and isn't done more often just because they are more expensive than standard servos.

The same questions arise as with any other use of a servo. Is the torque and speed available from the choice of servo enough to carry out the job? Throttles don't need a lot of force to actuate.

-Dave