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SextanteUK
27th Aug 2014, 23:33
Hi everyone, I was looking for S92 information and I just got this interesting post.
I'm interested in the cockpit vibrations. Maybe it's a stupid quesiton, but for those of you that have flown R44 or s300, do you have more vibrations in the s92? I friend of mine told me that big helis don't vibrate that much, he flies EC225, but flew R44 for 1500h or so, and he said R44 vibrates much more, that's what he said.
Anyone can compare these vibrations?.

Thanks for your help :}

SextanteUK
29th Aug 2014, 07:10
nothing? :E

SextanteUK
31st Aug 2014, 19:10
Hi everyone, tried to get information and also an answer in a S92 post, but nothing came up.

A friend of mine flies EC225, and has around 1500 in R44. I asked him about the vibration in the cockpit, and he told me that R44 vibrations were way worse than for example in that EC225.

I'd like to know about your experiences about this. Don't need to compare with R44, but any small trainer s300, R22, etc....compared to big helicopters.

Thanks for sharing! :ok::8

Brilliant Stuff
31st Aug 2014, 21:28
Can't vouch for the S92 since I haven't flown it.

I once flew a ropey R44 but it had been through a crash....

I have flown smooth EC135s and rough EC135s.

Does that help?

SextanteUK
31st Aug 2014, 22:41
was it the same heli in a bumpy day, or just an older 135 :E

my intention is to find out how "bumpy" and vibrating helis are, the big ones. I flew in R44, and maybe it was extremely hot or maybe it was just me, but I really found it a bit too much. BUT I love helicopters, and would love to fly one for a living.

unstable load
1st Sep 2014, 07:30
Lots of factors come into vibrations in helicopters, not least of which is the level of knowledge and understanding of rotor smoothing your Engineer has as well as the state of the mechanical bits that the whirly bits hang off.

Hughes500
1st Sep 2014, 10:09
Also depends upon rotor system

BO 105 rigid head very harsh ride
B206 teetering head so a bit bumpy
Sa341 / S300 /MD 500 fully articulated so all appear smoother.
having said that most blade shops and manufacturer's don't chord balance or make the blades weigh the same so then difficult if not impossible for engineers to make the rotor fly very well !

Aesir
1st Sep 2014, 10:37
The vibration levels donīt really have anything to do with the size of the helicopter. That varies.

The smoothest helicopter I have flown is the Bell 407. When well tracked&balanced it super smooth.

Helilog56
1st Sep 2014, 16:47
I am endorsed on 18 helicopter types and have flown more than 26 in my 38 years.....a Skycrane is by far one of the worst aircraft to manage shudder control and vibration. You feel like your retina's will detach from your eyes if a pilot makes a poor approach angle along with incorrect power application.....instrument panel mounts are a constant repair by the maintenance crew when we are breaking in new pilots.......;)

Modtro
1st Sep 2014, 17:26
Would love to fly a Skycrane Helilog56... but back to the topic and using your words, a few years ago I was flying a Mi-8-MTV-1 with no vibration absorver mounted on the rotor head and on every single approach, no matter what power management or approach angle whe had the feeling our retina's would detached at any moment and I had to keep my mouth open to prevent my teeth from destroying while colliding with each other.

Then there where the other ones with the dampers mounted which felt much smoother.

My smoothest helicopter so far has been a well tracked and balanced AS350.

SextanteUK
1st Sep 2014, 18:58
Thanks for sharing your experiences :)

I keep asking about the same in different places because I'm a CPL(a), used to "smooth" flights, but I really love helicopters, and as a spaniard in the US, I'm thinking about getting my CPL(h), to eventually go back to Europe an hopefully fly HEMS, even if takes years, but it would be very special for me.

So I paid $400 for a R44 flight, and I guess I thought so much about that day, that I imagined it would be like the most perfect and smoothest flight ever, but it wasn't haha. It was summer, in HOT Vegas . And i got vibration, wich now I assume is pretty much normal in this machines. Did any of you feel the same in your firat flughts? Do you get used to?. Back in 2005 I git a bit air sick in my firat piper flights, but I kept pushing and got used to it :E

RINKER
1st Sep 2014, 23:07
Hi SextanteUK
As others have said, it depends how well they are set up.
I have experience as pilot in a few.
Bell 206 a nice one quite smooth but with two bladed bump
R44 a new one similar to above a very old one quite rough
R22 similar to above but smaller so not as smooth.
SA341 Gazelle a few different ones ,smoother than all above.
As a pax in
MD500e 5 blades felt smooth to me

EC155 various, similar to Gazelle some better than others


Are you talking machine vibrations or turbulence ?
Also in particular The R44 6 cylinder engine vibrates a bit through the
Cab in comparison to a turbine
R

SextanteUK
1st Sep 2014, 23:14
Hi Rinker,

I'm talking the own machine vibration. Turbulence is there, nothing we can do :E

Don't pretend to be sissy, but you all know that heli training requires determination and a vast amount of cash/debt, so I'm trying to find out if that uncomfortable vibration I felt in my first is somehow common for first fligths, and if you get used to it after a while.

R44 I flew looked pretty old, but couldn't tell about its setup :8

SuperF
2nd Sep 2014, 05:18
interesting topic. it takes a good engineer, that knows their machine, to properly track and balance each type of helicopter. And then it takes an owner that wants, and is prepared to pay for, a smooth flight, and not just, oh well, its within limits "thats good enough."

we never accept "thats good enough" for very long, and spend a lot of time master balancing blades, getting the setup all right and T&B. In the older helis you also have to change out rod ends and bearings quite often, but it pays off with a smooth ride.

i took a guy for a survey a while ago, he wasn't happy that we "only" had a JR to do it in, he had been in JR's, 500 and 350's and said the JR was the worst, most bouncy, horrible machine to ride in. After we had done the job, about 6 hours of survey, he admitted that our JR was the smoothest helicopter he had ever been in, smoother than any 500 or 350 he had been in. Problem is, every minute in the air it is slowly working itself out of balance...

John R81
2nd Sep 2014, 08:21
There is a very interesting iPhone app which measures vibration in your R44 due to main & tail rotors and the engine fan.

As SuperF says, you need a good engineer and an owner who wants a smooth aircraft and will pay for the time taken to achieve that.

RINKER
2nd Sep 2014, 09:28
One thing I forgot to mention. Unlikely I know but if it was an
R44 Astro with the electric trim and no hydraulics upgrade you can
Get a lot of cyclic shake in them if you are on the controls.

R

SextanteUK
2nd Sep 2014, 18:10
So I guess I could expect "bad" vibrations during my piston training (they will try to shave money, as long as the machine is safely maintained), and hopefully, if I was able to land a job in a company with big machines, big budget, passengers, etc....I could expect smoother machines.

May I ask if any of you felt those "uncomfortable" vibrations during your first training flights? or that was actually part of the charm :E

Two's in
2nd Sep 2014, 18:49
(they will try to shave money, as long as the machine is safely maintained),

To state the obvious, any vibration will just cost you money in the long run, not addressing it is a false economy.

Remember that not all vibrations are obvious to the pilot, and the ones that are are not always severe. Main and Tail rotor fundamentals and harmonics are uncomfortable for the crew and pax, and for that reason should be tuned out, but there are some powerplant and transmission vibrations that are both dangerous and destructive that can only be detected by Vibe equipment. Bottom line is the Vibe equipment (hardly ever) lies, but "seat of the pants" is seldom objective.

FC80
2nd Sep 2014, 19:11
I don't mean this harshly but if you're really that worried about vibration then maybe helicopters aren't for you? Jets are nice and smooth. :8

By their very nature helicopters all vibrate a bit and like people have pointed out a lot of it is due to setup as opposed to the actual model of aircraft.

In any operator running a large fleet you will find variation from smooth to a bit shuddery or wobbly - engineers have time to get things running safely and within limits but can't afford to spend hours and hours tuning every machine in the fleet to be as smooth as silk.

For what it's worth, my opinion is that the 92 is smoother than a 44 almost all the time.

Efirmovich
2nd Sep 2014, 20:24
I would see vibrations as a bonus,,, At least you are still in the air !


E.

SextanteUK
2nd Sep 2014, 21:12
that's what I'm trying to find out FC80 :)

thank you all for your responses, it's really helping me a lot:D

Shawn Coyle
5th Sep 2014, 00:29
Pay attention to any sudden increase in main rotor 1/Rev vibrations!