Why is there a brake system on the rotors?

I could only think, after you landed, you want to slow the rotors down.

Going back to the number of hours flown. How long does it does it take pilots to rack up 100, 200, 300, etc. I’m thinking a 40 hour week, it doesn’t take long?

Edit: terrible voice to text error on my first sentence

Not trying to give the impression that they were telling me what happened in Vietnam, but the club I belong to, and several members served. I was just fortunate enough to be accepted as a friend, the only reason I have anything to contribute:
I know we have a few Pelicans who were there,like my friends, and we are lucky to have them.

The Navy series of H-60s all have rotor brakes, very similar to disc brakes.

The brake is used at sea to limit low rotor oscillations due to winds, sea state and ship movement on start up and shutdown.

On start up, both engines are started and remain at idle until the rotor brakes is released and the pilots run the power to the proper Np.

Reverse on shutdown. Engines are shut down and the rotor brakes is applied at a specific rotor speed and is limited to a specific PSI that the pilots can see as they apply the brake. It cannot stop the main rotor with power on.

Folded and stuffed:

http://forums.pelicanparts.com/uploa...1744632228.jpg

http://forums.pelicanparts.com/uploa...1744632228.jpg

Yes, i will bet the sea-going stuff has all sorts of special options to fold it all out of the way.
I was watching a vid some times ago, I think it was an R22..not sure, but the person be given the ride reached up to grab the m/R Brake !
The Pilot yelled at him a lot...
One has to be careful who you let near the sticks.
Some pilots pull the other side controls out so they are not there for an idiot to play with.
With The R22 , it cant be done with the cyclic, as its a yoke sort of deal. Personally, I HATE it.
But then again, I hate everything about the R 22 . Why stop with the little stuff? LOL

Afterburn, you have any R22 hours?

.

Wow. Something on the tail drive gave way? The trans and mounts look fine, the airframe failed?

The whole craft yawed 90° pretty quickly, then a portion of the tail broke off. The main rotor blades and mast, plus what I assume would be gearbox parts, separated a second or two later.

That’s what it looks like. Metal fatigue?

I think it was an earlier video posted, I can see the angled transmission mounts still in place.

I got 26 in taking my lessons. Then the wife decided i had better places to spend our money. Recip hours were $225 and turbine was $475.

After getting some stick time in a 206, I never wanted to get back in that Robinson again.


I was leaning to a trans mount strut failure. From what I can see, they look perfectly intact.

.

Vinman
If you can afford it, as you know, a turbine is a drug that you don't want to quit.
Pulling on the collective with a turbine in the back is way, way more confident they any recip will ever be .
The power too!


I finally got a better look at this crash video.
WOW!
That was horrific.
Yes, the tail boom failed near the gearbox in what looked like level flight.
Not a good look for the whole 206 fleet!
Straight and level is the easiest on all components.
Maybe there is an AD on this tail boom?
Or hours exceeded? IDK.
Not a lot was being asked as far as Torq.
Structural failure for sure!
AT that point, the M/R may have whacked the tail boom closer to the rear main bulkhead?
Then the whole transmission rotor head left the A/F platform, ripping out the mounting point! Not points, the whole thing! ?
Which is not normal in all the whacked tail booms I have seen.
I am no crash expert, but have been around a few...
None of that was not near normal.

When Juan talks, I pay attention. I doubt if I'll ever do a helicopter tour - ever. The risk seems high.

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A few things. The video above is good but it misses some essential elements.

Every aircraft, helicopter of fixed wing, has critical mechanical component times for maintenance or replacement based on expected usage (flight envelopes) of the air frame and the environment it is operating in.

For instance, the Navy H-60 has very different maintenance requirements due to being at sea than the average Army H-60.

My concern is that maintenance, especially corrosion, and other flight envelope issues (repeated landing and take-off far in excess of what Bell might have planned for an average 206) have not been addressed for the constant, repeated TO/Landings.

As another poster wrote, straight and level flight is the easiest regime for an aircraft, repeat landings and take-offs after 20 minutes or so of flight are not.

The company could have done everything properly based on Bells recommended maintenance and replacement curves and still not prevented the incident.

Think Hawaiian Air 30 years ago.

Unless something has changed, Bell uses a honeycomb structure for many parts, aluminum skin, typical bulkheads, rivited, and longitudinal, etc
The blades are composite with more honeycomb, a spar, maybe two, also maybe TT strap full length.
I am no 206 expert but they do have a lot of simluarties with the Huey for structure, or at least they used to have .
The mounts look good from what I got a glimpse of in the vid. Looks like the whole A/F had a failure?
Kind of domino effect?
Tail boom failed near fin, then the boom twisted off or perhaps got whacked from the blades,- more than likely.
Now, For some reason, which is truly different, the mounting platform for the transmission left the A/F.
I have NOT ever seen that, I have seen where one blade got shot off and the weight of the other blade swinging around ripped the transmission right out, but the A/F stayed intact.
I think there is a serious A/F problem at large here. (IMHO)

I for sure would not accuse anyone of anything, as for a certain it surely looks like a problem with the aiframe on several levels .
As you say, stop, go, and salt .
Only all day long every day!
Boom, bang and crap!
The gearbox falls off
The tailboom then departs with or without a strike.
And A/F structure comes apart.
That should not have happened even from a M/R strike! (if it was or did )
I know honycombing can delaminate, leaving voids in the structure.
I have seen it under the Huey engine (if I remember correctly)
But it has to be discovered and fixed.
In the military, every 100 hours the A/C goes in for a major service.
A HUGE inspection.
The TBO parts were replaced, and others that were worn and not caught in preflight/post-flight inspections all replaced.
A very thorough inspection by a factory-trained T.I. is done B4 work is started, which takes a couple of days even B4 the work is started.
A crew of about 6 very qualified men did the work, with meticulous paperwork work trail
of what is done and left undone.
The minimum a Huey would be in the shop even during the war I was in would be at least a week, and that was rare.
3 weeks was pretty normal for the turnaround and back out until next time.
I highly doubt this happens in the civilian world where dollars and pennies count.

I think the tail failed before the gearbox broke loose. Something caused a rapid 90 degree yaw, then the tail snapped (speed was around 100 knots?, I think)
and things went bad in a big hurry.

What could fail and cause the quick yaw at that speed?

Something seizing up between the gearbox and tail?

B4 the main gearbox failed?
Yes, it appears that way.
At this point, the whole A/f seemed to be compromised.
The dominoes went from the tail, dwn to the strongest part of the platform.
One disaster after the other.
If you are talented and have airspeed, you can set down a chopper with no T/R authority. This chopper did not allow that to happen.
It completely disintegrated.

The fact it was leased out of Louisiana leads me to believe it may have spent a lot of time as an oilfield taxi, exposed to salt air. Just a guess.

Crazy and impossible. Next.

Positively! WOW
Talk about unforeseen circumstances in both directions!
Glad you all made it through.
Sad that the others did not.