The XMEN Clan Forums

Well I got into RC planes about 8 months ago, after waiting about 28 yrs.
Been wanting to since I wasa kid. So thought I'd post a few pics of some of my planes. These are not the actual planes haven't made time to put them together just for pics. So there of the web adds for them.

#1 http://www.hangar-9.com/Products/Defaul ... ID=HAN1690
#2 http://ak-models.com/mm5/merchant.mvc?S ... Aerobatics
#3 http://www.rcuniverse.com/community/pro ... emid=93363
#4 http://www.nitroplanes.com/ulbi4043scni.html
#5 http://www2.towerhobbies.com/cgi-bin/wt ... XAEY1&P=PU

My pride and joys: AKA fraid to fly planes

#6 http://greatplanes.com/airplanes/gpma1350.html
#7 http://www2.towerhobbies.com/cgi-bin/wt ... LXMKB5&P=0

Last but not least ( I haven't put together for fear reasons) a limited edition: http://www.chiefaircraft.com/rcmsec/Mod ... ionSE.html

Sweet!

Some of my co-workers are into RC planes, and the field they use is only a few miles south of my place. I should get out there and photograph them (would have said shoot, but that might scare them)

Sad thing is, I work weekends now.

There's an RC club that uses one of the dry lake beds where I work. I've seen them early in the mornings some days. Some of the planes they fly are pretty big!

I've often wanted to do this too, Hammer.

Need to dig out my lightweight and get it going again.

So hard to get up early, tho...

We have an afternoon field, that means it's facing east so that noon or after the suns over or at your back. So theres not much need for getting up early. We fly till close to dark instead of early morning.

hehe, I fly my helo out in the street, driveway and sometimes even inside the garage. Greatest thing with flying electric anymore is Li-Po! OMG! On the standard 9.6V 650mAh NI-HM I'd get about 10-12 mins of flight time. Then I got a 1320mAh Li-Po @ 11.1V and I got bored of trying to run it down after no less than 40 minutes of flight. (sure glad I invested in some heatsinks for the motors)

Hey! That's something I could photograph! hehe, time to retrain my dad in the art of flying RC helos! (I don't think he's flown an RC helo since before they started putting gyros in them... lol)

Also, IMHO... ARF's are toys, scratch-builts are TREASURES! So maybe I should spend all this summer free time that I have and build me an airplane.

Hammer: don't you guys run into problems with the wind?

Maybe I've become accustomed to the constant winds out here in the desert...

hrmmm, been a LONG time since I last flew fixed wing... but I don't recall much difficulty with wind (unless it's gusting or you're flying a foamie).

Now, with my Blade CP... constant winds are ok, you can adjust for that, but you really really have to watch out for gusts. It's not that the helo blows away or blows out of control... the wind actually stalls the main rotor and it drops like a stone. (Some people say they get tonnes of extra lift in a wind gust, but I've only seen it stall... and I don't recall it changing based on the direction the helo was pointed. Any smart people want to take a crack at that?)

*shrug*

*points at rocket scientist*

if the gust is more of an updraft, then yes, you would see more lift. But if the helo is tilted down in forward flight, the wind can affect the amount of lift the rotor is producing, or if the gust was a downdraft, then obviously the attitude wouldn't matter. All aircraft are affected by up and down drafts, and not all wind on the surface is strictly horizontal in movement, due to trees, buildings, etc disrupting the flow of air. So you may be one of the unlucky ones and not get any updrafts in your neighborhood.

Winds not to bad untill around 25-30 mph. NOW if its a cross wind thats anouther issue all together. We fly on a real runway so its quite a bit narrow than a traditional r/c feild. So its hard to land the biplanes for all the lift in them and thier narrow landing gear. So on a windy day I fly generally a low wing hi speed plane. Makes for a less stressful day

Sorry... was busy with rocket scientist stuff.


Hammer: Ah gotcha.


Usually, we see 15-40 kts sustained with gusts anywhere from 20 kts to 60 kts. Crosswinds too.



As for the helo in the wind thing:

The key is to remember that as your blades move through the air, they are constantly seeing a different incoming airspeed. And lift is directly related to airspeed. Gusts are usually what causes the "turbulence" you experience on a commercial flight.

Think of it this way: gust hits right wing, and changes the direction of the incoming air from straight ahead to off to the right. That scenario means that some of the air is moving faster over the wing in certain areas than in others (faster at tips than at root). This faster incoming airspeed means more lift. So the wing wants to lift. The OTHER side of the aircraft sees a temporary decrease in incoming airspeed because the fuselage is blocking the slight adjustment from the gust. The left wing can even stall if the gust is strong enough and/or coming in at a sharp enough angle off of the centerline.

So your right wing has more lift, the left wing doesn't, and the right side starts to turn up. Only, most aircraft are self-stabilizing, so the plane will want to turn itself into the incoming gust. But that lift on the right wing keeps the plane from doing just that, and the plane rolls left and turns left, with a bit of sideslip.

If the incoming gust is only temporary, and not a definite increase in airspeed, then you get a one gust input (or a multiple gust input), and this means that you get a sharp jerk on the aircraft.


Now, take the above and add in the fact that incoming air will have a different angle relative to the chord of each blade as the blade moves through the air, and you see how it's not a simple matter.


Usually you'll see a stall with a rotary wing aircraft that small. That stems from the fact that most remote control rotary wing aircraft have very small wings compared to the speed of the incoming gust. They react very quickly, and very sharply to gusts. If you are flying over concrete or rocks, you'll likely see an updraft. If it's dark foliage or water, it's a toss-up as to what will happen. Some bodies of water act as heat sinks, others just carry their heat away with evaporation; for foliage, some plants constantly evaporate water, some don't. I can honestly tell you that mountains and dry lake beds give very good updrafts. Chances are, unless you are in a big enough rotary wing aircraft, you'll always see a stall in that situation. The only other situation which can give stalls without warning are microbursts and downdrafts. Microbursts usually are associated with thunderstorms/tornadoes, and downdrafts are both of those and mountains.


For those people that have seen extra lift from gusts, it was severely one-sided on their aircraft. And they likely had their blades trimmed or were quick enough on the yaw to bring the heli around.