Dang, thats an unfortunate crash. It honestly looks like a gust came in a caught the plane as he was taking off. Given how well the first flight went, unless a servo failed between flights, I have no idea what happened.

On a separate note, can we all take a moment for the fly that got caught up in the left prop and bounced around under the plane at 6:42? RIP Fly.

Actually, I think that fly is to blame. It hit the left prop and bounced off the underside of the plane. Maybe that was no ordinary fly. It was a SUPER FLY! The force of him hitting the prop threw it out of balance, then the subsequent hit to the underside picked the plane up in the wrong way causing the wind to catch it and throw the plane.

Case closed.

LOL on the fly!

I learned the hard way that it is often better to increase liftoff speed in gusty conditions. And ailerons into the wind of course. They looked neutral on take off.

Classic DC-3 stall. A ton of people have lost their HobbyKing DC-3s to that exact same stall. Plane left the ground too early, pitched up, stalled and in she went.

Look up people maidening the HobbyKing DC-3 and you will see this same crash a lot.

HobbyKing C-47 / DC-3 Maiden Flight NEAR DISASTER CRASH and first FLIGHT ! (6 min 51 sec)

Simply an early rotation, the plane started flying with nearly a critical angle of attack, one wing got more loaded up than the other as he continued to apply back pressure and the right wing stalled more than the left (hence the roll/low to the ground spin entry). Always unload the wings (relieve back pressure and increase forward pressure if you aren't too low already to do so) at the sign of an incipient spin or accelerated stall.

The model does an awful lot of jigs and jogs while in the air. Some of it appears to be the turbulence but some of it seems to be very set up to be very sensitive on the controls. That might have been a contributing factor.

Looking at the portion with the power up and takeoff that led to the crash. First off when the grass held back the gear and the tail initially lifted it slewed strongly to the right. That suggest one of two things. Either the right side motor is pulling much more strongly or there was a fairly strong cross wind from the left quarter. Given that it rolled strongly to the right I'm voting for trying to take off into a strong cross wind.

Earlier in the video the wind sock appeared to be right down the runway. But we've all seen where the direction can change quite a bit for a few seconds at a time then return to the more usual direction. He may have gotten one of those and didn't recognize it for what it was. Or it may have been just a momentary sudden direction shift. But given the way the model "hinged" in yaw when the tail first came up before the roll started I'm thinking that it was a longer shift which he should have recognized and dealt with by swinging into the wind more directly before applying takeoff power.

Originally Posted by Rampage

Classic DC-3 stall. A ton of people have lost their HobbyKing DC-3s to that exact same stall. Plane left the ground too early, pitched up, stalled and in she went.

Look up people maidening the HobbyKing DC-3 and you will see this same crash a lot.

YESSS !!! is the same situation, If we look well the HK DC3 video we can see FULL elevator during all the takeoff run, NEVER EVER do that with a tail wheel plane. The plane leave the ground early because is almost ready to fly but with full elevator is not possible without the stall, if work only with the rudder and leave the pitch alone is not a problem.

Look the original video and you can see FULL elevator during takeoff run .....

Originally Posted by PA22

YESSS !!! is the same situation, If we look well the HK DC3 video we can see FULL elevator during all the takeoff run, NEVER EVER do that with a tail wheel plane. The plane leave the ground early because is almost ready to fly but with full elevator is not possible without the stall, if work only with the rudder and leave the pitch alone is not a problem.

Look the original video and you can see FULL elevator during takeoff run .....

Exactly. Scale DC-3s are extremely intolerant of this. Like the real plane they have NASTY stall habits and will bite you hard if you abuse them. But if you keep the plane on the ground until it's ready to fly you'll be rewarded with a beautiful scale takeoff.

HobbyKing C-47 "What's Up Doc?" (3 min 43 sec)

If you abuse it you get this.

HobbyKing Douglas DC-3: Discontinued: WHY ?! (6 min 38 sec)

Some footage of stalls in the full-scale aircraft.

https://youtu.be/2tvsKLuEar4

DC3 Stall (2 min 4 sec)

Originally Posted by Rampage

If you abuse it you get this.

Moreover, until now, I don't understand WHY the people use ailerons during a stall in takeoff the LAST input control that we need to use during this situation is the ailerons ........ the RUDDER is there for something

Originally Posted by PA22

Look the original video and you can see FULL elevator during takeoff run .....

100% agree with that. I can see he was trying to keep the tail down because of the crosswind (note the windsock shot just before the takeoff roll). He should have taken off across the runway, with neutral elevator.

Bummer of a way to learn that lesson.

Andy

On our grass field, my scale or warbird taildraggers won't taxi without nosing over if I don't use full up elevator. So it's okay to start the rollout with full up elevator but then it should be neutralized before liftoff. And in a crosswind, same with the ailerons. Turned into the wind for rollout but then gradually back to neutral as the plane lifts off.

Looks to me like it was not a dead cross wind, but it was slightly quartering from behind making it a slightly downwind takeoff - in addition to what's been said above. Check the geometry on the grass lines vs. wind sock starting at about 6:10

Use full up elevator only for the initial pull away on grass, when the plane starts to roll let the elevator back to neutral over a couple of seconds to allow the tail to gently rise then apply power to take-off speed, preferably not across wind as this one was. Maybe even more speed might not have saved this one.