DiscoWings

My Feedback: (76)

http://www.youtube.com/watch?v=K9w00A6e478
reversed aleirons?[&:]

jetmech05

wow what a loss...
i noticed some things in the video.
1 the wind was blowing pretty good during the taxi test.
2.the sun was brighter during take off so the weather might have improved?
3 the aircraft rolled in the direction the wind would have rolled it.
4 the most damning piece of info yet. the aircraft rolled in the direction the ailerons were thrown (look at the right wing)
ladies and gentlemen if the ailerons were reversed. then remember what i teach all my students. preflight preflight and when you finish that, do a preflight.

casniffer

My Feedback: (1)

Looks like reversed ailerons to me. You can see the right aileron deflect down. You'd think the pilot would be more conscientious and diligent with a preflight considering the investment he made in this plane. I do it on every plane on every flight since I have a radio with 14 model memory.
Its a shame that something so simple contributed to its demise.

CASniffer

ed_cook1979

My Feedback: (4)

I almost wonder if That thing had enough power. it looked Like it got yanked off too soon and stalled

Deadeye

A real shame, that one.

skiman762

If the Ailerons weren't reversed then he did a real dumb thing by turning down wind after take off

TankHunter

My Feedback: (1)

if u look at the wind bag??? u will see it was a cross wind so there was no "going with the wind..." also if u have a halfscale plane ... warbird ...retracts...many servos.... u should use an engine with enough power.

My opinion looks like a tip stall.. not enough airspeed and she started to tip ... wind grabbed the wing and continued to push it over... not enough throw to right her before impact....

what a shame

skiman762

yeah I saw the wind thingy looked like the wind was going 90 degrees to the runway rt to left and the rt aileron was going down for a left turn so if he was stalling he didn't correct properly but if he was turning down wind it killed his airspeed and lift and that's all she wrote

wiz310

I would have thought people with some aerodynamic knowledge would think a little bit more before delving into the downwind argument. An aircraft that is airborne in a parcel of air feels no wind. its only relevant as a referance point to the ground. 40knts airspeed is excactly that, 40knts airspeed. now Groundspeed is a whole different matter, but does not effect an aircraft in the air.
Just my 2c worth.
It looked like a lack of aileron authority to correct a gust induced/stall induced roll. maybe from either being to slow, or just not enough throw/size on the ailerons.
Sad loss of a beautiful craft whatever the cause. []

BKH

My Feedback: (4)

Looks like the right aileron was down, rolling her right into the ground. I'd say reversed ailerons!

erbroens

You guys didn´t got it... it was a 100% scale kamikaze flight. The target was the builder´s brother-in-law at the end of the runway, asked to take a close pic of the plane at takeoff....


Enrique

wiz310

Bwaaaahahahaha. I was going to sugest that excact same thing............... something along the lines of him being a scale fanatic and this was a Kamikaze flight. I'm glad I'm not the only one with a slightly sick sense of humour.

erbroens

slightly sick sense of humour? no! completely sick... LOL

Enrique

Iturnright

Now that certainly looks like reversed ailerons, but really, who, when about to fly that kind of model, would make a mistake like that!

skiman762

[&o] My bad what I was trying to say

skiman762

The problems aircraft have with wind shear occurs when they are flying only slightly above stall speed. This happens either during takeoff or landing. During this time a major change in wind velocity can lead to a significant gain or loss of precious lift. When the plane is flying into a head wind, extra lift is generated by the speed of the wind, and often to compensate for this during a descent, power is reduced. If that wind suddenly switches to a tail wind or decreases in velocity, lift is reduced. If the wind shear is violent enough, it can even cause enough loss of lift to result in a stall. This loss of lift is directly proportional to a loss in altitude. The following three things are vital to the survival of an aircraft while experiencing extreme wind shear: altitude at which shear is encountered, the pilot's experience, and type of aircraft

this is from a avaition weather site

jetmech05

wind shear? in a full scale aircraft skiman has a point.
one difference in rc is has how much power there is compaired to full scale. rc has much more power available.
another reason i dont think windshear is a factor is we're talking about a piston powered aircraft over a turbine powered one as are most airliners today. the power response with a piston powered aircraft is much faster than with turbine. so once the wind shear is encountered, well there is much more power available quicker.
wiz 310 please remember 40 kts of airflow over the wing would be reduced to 30 kts if you were flying directly into a 10 kt headwind and changed heading

Flak

My Feedback: (1)

Too Much Saki...Bonzai!!!

"Keep 'Em Flying!"
Flak

skiman762

Good info
but the laws of physics don't apply just to full scale aircraft
remember a stall is a stall it doesn't matter full scale or model
It is just the point where an airfoil can no longer provide lift
I guess I shouild have just said
was if the ailerons weren't reversed then turning downwind on takeoff is a dumb
yes I agree models that are overpowered can get out of trouble that full scale planes can't maybe some fighter jets can get away with a few things
In this case I think plane is under or should I say scale powered and didn't have any extra power to use
the plane weighs 330ibs and only had a 250cc engine
anyway sure didn't mean to get a aerodynamic argument going

skiman762

On that note
I must load up the planes and get on to the field to test my ability to defy the laws of physics
I already tested the one about two objects occupying the same space at the same time, that results in small pieces of balsa
Have fun after all it just a hobby

infiniti_drifter

Hey,

What a shame. Viewing this video reminded me of an article that I read years ago. Mr. Saito, the owner of the model engine company was building an exact replica of a Zero. Now I do not remember the scale, but it was something big. He was going to have a custom engine and everything, looking at that vid(-sound), location is Japan, I think that it might have been his model.

Cheers,

Sebastian

Robotech

My Feedback: (9)

Definitely looked like a tip stall. The thing was beautiful but seemed grossly underpowered. The tail barely came up before it lifted off.

Mud Duck

My Feedback: (94)

I admit, the comments about this being a "Kamakazi" airplane definitely made me chuckle; a slightly evil chuckle! [X(]

It's a shame no one within RCU has contact with these folks to find out what really happened, but if I were to place my money on the table, I would definitely say it was reversed ailerons, which just blows my mind.

I have a differing opinion on the "cross-wind" as well. I don't believe there was a cross-wind at all. I think it is a low-quality video camera angle perception problem. The windsock in the video appears to be some sort of a parachute on the end of a long bungee cord. If you look at the video again, especially at the very beginning where all of the people are gathered around the Zero at about the 8 second mark you will get a glimpse of the windsock from that angle and it clearly shows that the wind is going down the runway or ever so slightly to the right. If you look in the video later and visualize the bungee cord being pulled to the back instead of the side, I think you'll see what I mean. So I don't believe the crosswind was a factor at all, if anything the wind helped get the plane up.

As for the powerplant, it appears to be perfect. Slightly more scale-powerful than what the full-scale must have had. How many full-scale WWII airplanes did you ever see 'jump' right off the runway? They all had to be driven down the runway a while to build up enough speed to get them into the air. The Zero in this video had the most scale looking take-off I have seen in a long time. It looked exactly like a full-scale Zero getting off the ground, it was flying on the wing. He didn't yank it off the ground, the plane rose up off the ground and for a second or two looked so very magestic. Good grief, it was a 250cc engine on a 330 pound airplane, there may be full-scale ultralights out there with similar powerplants.

About two seconds into the flight, it appears that the model may have been slightly out of trim or perhaps the wind or torque made the plane bank ever so slightly to the left. You can see the pilot feed in what would have been the exact amount of aileron needed to level the plane off, but instead it started banking further to the left in the wrong direction, then you can see where he must have really started to pucker and fed in more aileron (unfortunately it was going in the wrong direction - and the aileron looked like it was more than adequate in size) which put the Zero nearly at knife-edge before the pilot stopped adding aileron, but probably didn't have a clue as to what to do with reversed ailerons and besides in that flight attitude there wasn't anything that could have been done as time and altitude ran out. When the airplane reached the knife-edge position - that's where it "tip stalled" - not before.

What a shame that such a nice airplane ended up in a pile. The people screaming as the plane went in is quite dramatic as well. I just cannot believe that they didn't check the direction of the ailerons prior to take-off, it boggles the mind.

Oh well, hope they're able to get it rebuilt.

Hobie

[X(][X(][X(] It's hard for me to believe someone spending years of work and lots of $$$ could make that rookie of a mistake too . The right aileron sure looks like it is down but even with broadband I had to pause it a couple of times to be able to tell . Instead of ailerons being set up back wards why couldn't it be radio interference like caused people to die not long ago or equipment failure ? Unless someone hears directly from the pilot we won't know for sure . You can't see what the left aileron is doing we are assuming it is up .

skiman762

at 1:08 you can get a real good look at a stiff breeze blowing across the runway at 90 degrees from the rt the grass and sock are moving pretty good
a rotax 582 only puts out 65 hp about what that plane would need just to be scale power for it's weight I doubt a 250 puts out near enough hp for that plane though it did lumber into the sky for a few secs
I believe a really zero's AUW was about 5600lbs and it had 1130 hp about 4.95lbs per hp which should mean that the model would need about 66hp for scale