Video - Flapping to Equality / Dissymmetry of Lift

[Mitchaa]

Great video showing pitch changes of the MR blade during a revolution. Check how the advancing blade reduces pitch and the retreating blade increases pitch. Pause the video to show the pitch increase towards the tail and then the pitch decrease as it advances towards the front. Perfectly displaying flapping to equality.

I put a GoPro (https://www.facebook.com/gopro/?fref=mentions&__xts__%5B0%5D=68.ARAGDdaUL1Y8sxXO43vmDNpOxv9mntDw6SftCbTBqD JVJhLf7owdq1vrcLEL_USnKoK80Dy8mvD4QVIiD80wJJIRByV38DlE_Kjc8D X1RcfF5b_VMFV-U9QJuqPjEqZSeIF9YMk6lFUpd9DFk-_ignjiyYJr4il0OXpja1eNQ0rXN9TNbX4BN2VwdQSNJwuDq8R4KyzCEW3JME KLI9T7JyMsNb52dBcNSGW3bccud1d79oNyy7kkO-Ax76n2KBVlE6NtoFqxP0eodKT-gGtfsVTwi-2TAHbzrLYf7-mN9o1TCsG10a99mL66feroxpABrT0y4XBAANKfxTeCVMORzaX_dhukkqWvrw VpPl5uJTgr1Dn0FAaguSshm9RXpa1mp4kUgJ0F1Wd_dsNfr10pKIcIFOET2u JJ2CpjQU0&__tn__=K-R) on my Rotor Head Assy so you can see exactly what a Main Rotor Blade does on EVERY revolution in the experimental BO-105 helicopter. (Shot at 240fps slowed to 30fps)

How cool is that



https://youtu.be/Pu48f7s5Ru8

[gulliBell]

I'm surprised by the movement of the pendulum dampers.

[Hot 'n' High]

I'm just surprised - period! See the current thread One Nil; Cellphone vs Robinson!

Now, not saying you can't! I believe as a "Temp Fix" the FAA leave it up to the PIC - but I'm no expert on FAA rules so don't listen to me. But I did work in Mil Trials myself several times and we used to stick all sorts of stuff all over the place - and even convince the odd TP to go fly it to see if it worked! :p

Fitting something to the MRH? Sporty! Hope this doesn't encourage your ave GP and R22 owner - given the comments in the other thread and the Safety hoops we had to jump through for even a small trial fit. But Chuck Aaron looks OK...... and I'm sure there is more to this in terms of how it all came about!

And looks cool!! ;) H 'n' H

[Hot 'n' High]

Too late! https://www.youtube.com/watch?v=7DkgNw3hTKY Seems well strapped on.....! :rolleyes: H 'n' H

[tartare]

OK.
Intriguing to see, but am I alone in thinking this is insanely dangerous?
You put a Go-Pro on a rotorhead - for real?
Are you a licenced aviation mechanical engineer?
What if it had cut loose?
What if it caused said rotorhead to be slightly out of balance?
I'd be interested to hear further details.

[Ascend Charlie]

Sorry, Mitchaa, but it ain't "Flapping To Equality". It is "Blades flapping as dictated by the swash plate."

FTE will only happen when the cyclic is neutral and a puff of breeze causes a differential in relative airflow between advancing and retreating blades. The advancing blade will flap up, and the retreating blade flaps down, the opposite of what is shown on this video. This FTE makes the disc tilt backwards, and the helicopter would then move backwards - but then the relative airflows are then reversed, the disc flaps the other way, and you are into the realm of dynamic instability.

BUT! The pilot sees that the disc is flapping back right from the start, when he wants to go forward, so he uses cyclic to make that happen. End of FtE. The aircraft does what the cyclic tells it to do. Advancing blade goes down instead of up, disc tilts forward, total rotor thrust points forward, and away he goes.

Nice video, though, and the pair of balls flapping away is doing its job of absorbing vibes.

[Robbiee]

Great video showing pitch changes of the MR blade during a revolution. Check how the advancing blade reduces pitch and the retreating blade increases pitch. Pause the video to show the pitch increase towards the tail and then the pitch decrease as it advances towards the front. Perfectly displaying flapping to equality.



https://youtu.be/Pu48f7s5Ru8

All that did was make me dizzy :uhoh:

[MikeNYC]

OK.
Intriguing to see, but am I alone in thinking this is insanely dangerous?
You put a Go-Pro on a rotorhead - for real?
Are you a licenced aviation mechanical engineer?
What if it had cut loose?
What if it caused said rotorhead to be slightly out of balance?
I'd be interested to hear further details.

You must not be familiar with the name Chuck Aaron, the creator of the video. A quick Google search may answer your questions. The fact that his BO-105 is in the Experimental category supports the legality as well.

[John Eacott]

OK.
Intriguing to see, but am I alone in thinking this is insanely dangerous?
You put a Go-Pro on a rotorhead - for real?
Are you a licenced aviation mechanical engineer?
What if it had cut loose?
What if it caused said rotorhead to be slightly out of balance?
I'd be interested to hear further details.

Seriously? Are we so risk averse that we can't accept that someone may actually know what they're doing :confused:

Previous films (yes, with cameras with film stock inside) show how blade technology has changed over the years. And explain why the Bo105 and others are known as rigid rotor systems :ok:

1946, and the film that is claimed to dissuade pilots from flying rotary ;)

https://youtu.be/p4VLhnTZpb8

S-56, sometime in the late 1950s

https://youtu.be/srjbnvTWRJI

I think this is the S-56 footage, as originally shot

https://youtu.be/eaE807WKN_8

Mil-8, more recent footage

https://youtu.be/FlP7zSBcbuI


A modern BERP blade shown from 1:28 onwards. Seeing Colin Hague is a blast from the past!


https://youtu.be/ki-CxkRuAxY?t=89

[tartare]

Nope - no way of me telling simply from viewing the link on the forum that the poster is Chuck Aaron.
If he knows what he's doing - and clearly he does - and is flying an experimental category machine, then that's fine.
All I saw was someone unknown, strapping a Go-Pro to a rotorhead.

[RVDT]

All I saw was someone unknown, strapping a Go-Pro to a rotorhead

Really? I didn’t see that in the video. Must have missed something. Just watched it again. Didn’t see “someone”.

[Cornish Jack]

John E - "Colin Hague a blast from the past", indeed. Worked with him at Boscombe in the 70s. He was D Sqn SPLOT (or some such Dark Blue terminology:E) when the Icing trials Wessex had a camera fitted with prisms to monitor each blade in flight. I believe this was a first and the resultant viewing was 'interesting'!!:eek:

[Al M]

John E:
The S-56 video is deceiving. The camera was mounted on the rotor hub inboard of the flapping,hunting, and pitch hinges so you see much more than blade bending. Later on a camera was mounted on the pitch horn of the S-61F which only showed blade bending, both flatwise and edgewise. It was very benign. This was also repeated on a CH-53 with the same results.

[RMK]

Scariest one on this thread is post #4 which shows a gyrocopter MRB is held on by nothing more than a few hex bolts - damn?

For our resident RHC fans, in comparison, that makes an R22 look like its built like a CH53.