triumphantduke
Model 5 QB #16
title says it all - I went to youtube university and thought of yall
. Thought it'd be an interesting discussion since the bearhawk design asks for slight toe in.
Toe-in and Toe-out - what are your thoughts on Jonas Marcinko video
- Thread starter triumphantduke
- Start date
title says it all - I went to youtube university and thought of yall
. Thought it'd be an interesting discussion since the bearhawk design asks for slight toe in.
Good to hear from you Isa, I hope all is well at your place and that you are finding some time to work on your plane! The Bearhawk gear alignment is measured at a specific gear spread, and at that spread it has toe-in, but the alignment changes depending on the gear spread. So it's even more complicated!
Bcone1381
Finished Patrol
Man, I started watching the video. I stopped. I fly. I love the results. So what i experience is beyond schoolhouse theory...its experience felt outside in the play ground. The factory gear rigging complied with Bob's instructions. If I was in Vegas, I'd bet Bob says something darn close to neutral. So I can't contribute to anything except build it according Bob's plan. If the video teaches something different please throw up a red flag. I think another factor is when the tail is on the ground then tow-in changes ever so slighty.
Battson
Moderator
To be honest, I struggle with the whole "flying circus" crowd and their video creations.
There's far too much "look at me" factor in the videos, yuck. But there's not nearly enough: actual aviation credentials, respect for the aircraft or environment they fly in, or focus on getting the aviation fundamentals right. Let alone any real engineering knowledge or experience, heaven help us if they are venturing into the realm of testing the engineering theory with science...
There's far too much "look at me" factor in the videos, yuck. But there's not nearly enough: actual aviation credentials, respect for the aircraft or environment they fly in, or focus on getting the aviation fundamentals right. Let alone any real engineering knowledge or experience, heaven help us if they are venturing into the realm of testing the engineering theory with science...
triumphantduke
Model 5 QB #16
thanks, I ended up taking the kit to stol-it for them to help me finish it. I faced the music with the amount of time on my hands after our first haha. Basically just need to finish the panel from my end.
I'll keep that in my back pocket, the next time I bother Bob just to hear his thoughts on it. A head on high frame rate, with a good zoom video camera to capture to Bearhawk landing or gear types would be interesting. (take note bearhawk youtubers! haha) I think this is one of those things that like Battson said, generalization doesn't work without taking into account the specific airframe geometry. I wouldn't challenge that it was the best thing to do for that RC spring gear though.
For reference, all Bearhawk gear are neutral toe at the standard gear spread.The toe will change slightly with articulation of the gear.
kestrel
Offering Bearhawk rides
While the video's conclusions match with my model of the world, the testing methods don't accurately model the dynamics of a real system. It might be a relevant test, it might not be. I'm not going to take it as proof that I'm right.
My own Bearhawk happened to have about 3 degrees per side toe in when I bought it. It was a docile machine so I saw no need to mess with it. Then one day I had a gear leg fail on a benign landing. The field repair to get it out of the field and back home resulted in 15 degrees toe in on the repaired side. At that level, the 31" ABW wheels were trying to buckle underneath the aircraft as they attempted to drive toward each other. The plan had been to do a high speed taxi test before flying. Taxiing was so awful that I decided I'd be happier in the air and took off. I landed on a section of gravel back home to maximize scrub and minimize bite. The asymmetric toe resulted in a sideways crabbing behavior that was excruciatingly painful to experience for this long time taildragger pilot (learned to fly in a J-3, first solo on 16th B-day) who was strongly conditioned to keep the nose pointed in the direction of travel. Outside of that problem, the landing was uneventful. The Bearhawk (at least the larger ones) have properties that would present challenges for a C-172 pilot who hasn't had appropriate additional training, directional manners is not a problem with them.
My point? If 18 degrees of total toe in with the track 6 degrees off straight can be flown, I don't think that symmetric toe anywhere within a few degrees of straight is going to result in bad manners.
My own Bearhawk happened to have about 3 degrees per side toe in when I bought it. It was a docile machine so I saw no need to mess with it. Then one day I had a gear leg fail on a benign landing. The field repair to get it out of the field and back home resulted in 15 degrees toe in on the repaired side. At that level, the 31" ABW wheels were trying to buckle underneath the aircraft as they attempted to drive toward each other. The plan had been to do a high speed taxi test before flying. Taxiing was so awful that I decided I'd be happier in the air and took off. I landed on a section of gravel back home to maximize scrub and minimize bite. The asymmetric toe resulted in a sideways crabbing behavior that was excruciatingly painful to experience for this long time taildragger pilot (learned to fly in a J-3, first solo on 16th B-day) who was strongly conditioned to keep the nose pointed in the direction of travel. Outside of that problem, the landing was uneventful. The Bearhawk (at least the larger ones) have properties that would present challenges for a C-172 pilot who hasn't had appropriate additional training, directional manners is not a problem with them.
My point? If 18 degrees of total toe in with the track 6 degrees off straight can be flown, I don't think that symmetric toe anywhere within a few degrees of straight is going to result in bad manners.