Rotor blades collision causes

I know that this tends (always) to happen when you accelerate and push the helicopter downwards (it will give warning beep) but am I right to say that its also dangerous to tilt the AC downwards even a little when the AC is trimmed?

Or is there something else I am doing wrong?

I am getting these inexplicable crashes every once in a while and as far as I can work out it seems to happen mostly when the AC is trimmed. It sometimes happens when tilting downwards (not steeply) and sometimes when I am banking but I think when I am travelling at high speed or probably accelerating (But I think maybe not always).

It happens so suddenly that I am often at a loss to what I did wrong but am I right in my assumptions? That any high speed changes of direction (especially down) should NEVER be attempted while trimmed?

I spent so much time focusing on take off, landing and blowing stuff up, that I have neglected to focus on what would really matter in real life- cardinal rules to flying safely!

I've come to realize to my deep surprise that trial and error is probably not the best way to learn how to fly a helicopter!

Thanks guys!

Both rotordisks rotate to opposite directions and they collide when the collective is pulled at high speed when both rotos are coning.

But to coning doesn't happen on same side but opposite, so when lower will cone on left, upper cones on right (rotate opposite directions) and collision happens when lower left hits upper left part.

There is a easy fix for it, when at high speed forward or high speed vertically, avoid fast collective pulling.

Pulling collective tilts the rotor blades to higher angle of attack, meaning it will catch more air and then will start coning.

Helicopter is to be flied like an airplane at high speeds, vertical or lateral, so ease the collective and use cyclic to maneuver.

You will learn fast enough the amount you need to do maneuvers.

The trick is that collective is used for turning and banking in KA-50, so lower angle of attack, less capable to turn and roll.

The cockpit has a angle of attack instrument for blade angle, keep an eye on it when testing the limits.

When the audible alarm goes off, avoid collective pulling, instead ease it. And avoid excessive banking as pitching up.

Forget the trimming, as it has nothing to do with it. You can have exactly same flight parameters without any autopilot channels and you have exactly same limits.

Rotor blades collision causes

It shouldn't really have anything to do with attitude, what's happening is you're overloading the rotors.

Part of what's happening is that the main rotor of a helicopter cones upward under heavy load (lots of collective) and tilts to one side based on speed. Since the Ka-50 has two rotors on the same axis spinning in opposite directions that means the gap between them gets smaller the faster you go.

Next time you fly try getting up to high speed (250 kph+) in level flight and check the external view, you'll see what I'm talking about.

As far as avoiding the phenomenon goes, avoid high g maneuvers at high speed. If you start getting the warning beep it's usually time to slow down.

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Right rudder is also a risk factor. The rudder changes the AoA of the rotors, not in unison like the collective but in opposition. When you press right rudder, the lower rotor will cone more, the upper will cone less.

Wow damned thing is a death trap! Did many real Ka-50 pilots meet their end due to this mistake? Mind they probably listened in basic training!

Think you're right guys about the collective. I think what I've been doing is trimming (poorly) and then trying to straighten out by using the collective and doing it all rather too quickly- snap. So will ease up on my use of the collective and see if it helps. Will have to alter my whole method of flying now though quite hard to resist!

Wow damned thing is a death trap! Did many real Ka-50 pilots meet their end due to this mistake? Mind they probably listened in basic training!

You can be extremely aggressive with the controls if you're in the right envelope. With practice you develop sort of a sixth sense for it. It's always good to err on the side of caution, though.

You can be extremely aggressive with the controls if you're in the right envelope. With practice you develop sort of a sixth sense for it. It's always good to err on the side of caution, though.

Thats one thing about simulations that even VR cannot remedy. That without a fear of death I am always going to be flying like a total berk and in no way the cautious little mouse I would be at the helm of a real KA-50! Still you can have a lot more fun that way!

Thank goodness for virtual death :)

Just fly the helo around an airport. Do that for hours and hours. Practice practice. Set out a racing circuit on an airfield and try do it quicker each time. Include high-speed changes of direction, and slow speed.

In time you'll get the sixth sense feeling Sobek is talking about.

Once you get it, you can REALLY push the Shark a lot!

The thing is though I thought my skills were really improving! It was just this one, but very fatal flaw that was occasionally occuring that told me deep down that despite flying well 95 percent of the time, I was actually an awful pilot who in real life would already have died a thousand deaths. The amount of helicopters and money I would have wasted the military on account of my premature eject-ulations would have been astronomical!

Now that its sorted out though I think I've got a good foundation to build on.

It wasnt the warning sound collision that was causing me to crash, those were easy to understand and avoid. That one tends to happen when pushing down on the collecitive combined with a rapid desent.

It was occuring without any warning sound whatsoever and often during pretty level flight (but a slight dip caused by using the collective) which made me think the G's couldnt be too bad.

Now just visualizing what happens when you suddenly pull down the collective seems to make sense, the lower blades cone upwards and collide with the upper?

It dosent always happen though so that made it harder to track down. I would use the collective for everything, it felt pretty natural and more often than not got away with it!

For example if I was being fired on, I found suddenly hitting the collective was a pretty good way to avoid the incoming barrage as you drop down in a more vertical motion.

One more question. Whenever I go into high speeds warning lights will flick on in the top panel. I know this is a high speed warning of sorts, but what excatly are they warning me? Is it simply not to attempt any high G maneuvers. Or are they actually telling me that I shouldnt even be going that fast?

One more question. Whenever I go into high speeds warning lights will flick on in the top panel. I know this is a high speed warning of sorts, but what excatly are they warning me? Is it simply not to attempt any high G maneuvers. Or are they actually telling me that I shouldnt even be going that fast?

Those are most likely the governor warning lights, which indicate that the engine power is being capped artificially because you are commanding way too much torque.

You should not operate continuously in those conditions, as it severly impounds the engines service life.

There is a gauge on the front right panel that indicates what power regime you are operating within. I don't remember the maximum allowed times for the power regimes but you can find those in this forum if you search, i'm sure.

Just fly the helo around an airport. Do that for hours and hours. Practice practice. Set out a racing circuit on an airfield and try do it quicker each time. Include high-speed changes of direction, and slow speed.

In time you'll get the sixth sense feeling Sobek is talking about.

Once you get it, you can REALLY push the Shark a lot!

^^ this

I found racing through and over the valleys in the Caucuses helped me learn to ride the very edge of its limits.

^^ this

 

I found racing through and over the valleys in the Caucuses helped me learn to ride the very edge of its limits.

I find target practice missions good for practicing flying more acrobatically. Those are really fun!

What about fuel, I've been carrying 100 percent fuel do you guys think I should drop it down to 70 percent and lighten the load?

This crash isn't always caused by the collective it's quite hard to replicate and remember exactly what happens but it's perhaps when I push down too quickly after having rose up quickly at high speed. It's still happening more than I'd like, if you were teaching a rookie and had to tell him some rules to ensure this accident never happens, what rules would you warn him never to break?

when near VMAX, do not induce violent pitch, especially down, do not induce violent roll, especially right, do not induce violent rudder, especially right

if you think you are going to have to do violent maneuvers, maintain <220kph

don't exceed VMAX unless you are flying in a perfectly straight line, better yet don't exceed VMAX.

There are two yellow lights on the upper panel that tell you you've got your collective set too high(LM/RM POWER), just make sure those lights are never on, and you're fine.

also yeah VMAX is a thing, with a full load you can go around 270kph, empty you can go around 305kph...

when I first started with the shark, I never took over 50% fuel at first, and kept the weapons load low as I usually crashed before that anyway:joystick: :music_whistling: its a very powerful chopper, you gotta be easy with the controls and slow the axis' curves down (espically the collective) helped me be a lot smoother on the controls

There are two yellow lights on the upper panel that tell you you've got your collective set too high(LM/RM POWER), just make sure those lights are never on, and you're fine.

That's not really correct. The yellow lights turn on when you try to exceed max power (or rather max EGT IIRC, the engines are temp redlined), max continuous is much lower and is not indicated by any lights. There's only the indicator on the front right panel. If you fly continuously at more than max continuous, the engines power will degrade noticeably over a long mission.

That's not really correct. The yellow lights turn on when you try to exceed max power (or rather max EGT IIRC, the engines are temp redlined), max continuous is much lower and is not indicated by any lights. There's only the indicator on the front right panel. If you fly continuously at more than max continuous, the engines power will degrade noticeably over a long mission.

Yeah you're right this crash I've been getting is more sudden and hard to understand theres generally no warning lights or beeps, it just happens.

Fly Fly and fly even more :)

Set yourself a course and stick to turning points and tasks you set for yourself. As sobek says, over time your turn will be better, be on spot, you wont gain or loose altitude ( if you watch out and care about clean flying being a present mindset ).

Load that Beast to the max, max TO weight and fly same again. Take note of how much that does differ, from 50% fuel to max TO, a totally differently behaving bird in some aspects. You really feel the added mass, everywhere.

In combat, you have to climb many mountains loaded like a truck, at night, NOE...

You have to know how to fly the Shark "heavy" and you should accept that there are things it will never do without causing serious headache, workload, or breaking apart :P

The shark can dive at 450km/h easily, you can also get out of this dive alive, just dont pull collective until you have slowed down considerably. Climb to 4000m and DROP down with collective all the way DOWN, nose DOWN 45°...gain speed, 450 is ok, pull GENTLY out, dont flare too early too fast, still collective ALL THE WAY DOWN...at 300 you can add "some " collective again...do it a few times, its fun too.

In combat you usually dont fly 4k high, but its good to know what it can do and how.

Dont apply Full-Full ! never ever never do FULL COLLECTIVE and FULL CYCLIC same time.

When you start to learn Helicopters you might find yourself doing just that sometimes. It wont work ! The harder you need to work cyclic the more your collective should be at or around hover power setting, that will give/allow the swashplate the most travel...aka authority.

Just some basic tips what not to do :)

other than that, become friends with the AP ! If you like him or not, he will always be there

Dont apply Full-Full ! never ever never do FULL COLLECTIVE and FULL CYCLIC same time.

!!!

You can be brutal with the controls & not break the machine - if you remember that advice

Well Ｉ am still going down in pilot error induced firey balls of smoking death. But good news is every time it happens now, I realize why, and often even can anticipate my own death before it happens!

Will just suddenly realize way too fast, shouldnt have pulled that, or moved like that at this speed and sure enough snap, and down we go!

:-)