Here we go again!

[Cletus]

Hey, Happy Father's Day guys!

She was flying around really SWEET! ....did a flip and when I gave negative in the inverted attitude, I realized that I was in NORMAL and not Idle-up!
PANIC and 20-lbs of beautiful machinery hit the ground pretty hard!

[coopercobra03]

Wow that's horrible to see!

[tott]

Ouch.....sorry man.....

[Intrepid175]

Ouch.....Cletus.....we feel your pain!

You have now crossed over from the ranks of those who are going to, to those who have. Bet it's a "long" time before you do that again!

Best of luck on the rebuild,
Steve R.

[yf222000]

I hope the motor and electronics are ok.

[Skiddz]

Man, that sucks.. I've done that with small electrics (the "oh crap, normal mode!!" bit) but never any of the bigger birds..

I hope the engine is ok.. The rest is a few turns of the wrench...

[cbdane]

That's very painful to see Cletus. I have complete faith she'll fly again, though.

[Cletus]

Thanks for the encouragement guys .....I should have known better and ensured I was in the right mode before going aerobatic. Just got caught-up in the "how sweet she flying!" moment


Damage Report:
Not as bad as it looks. The engine’s fine and so are the servos and electronics.
Just the usual, damned crash damage list: skids, main-blades, fly-bar, main-shaft, feathering-shaft, main-gear, boom, torque-tube, tail-shaft, tail-blades, canopy.

Off to Germany on business for a week come Saturday, so I'll deal with this stuff when I return.

[terrybeb]

Glad to hear it's not as bad as it could have been.

[Intrepid175]

Originally Posted by terrybeb

Glad to hear it's not as bad as it could have been.

+1 on that. The turbine is what I would be worrying about. As long as it's Ok, as Skiddz says, the rest is just a few turns of the wrench!

Be safe on that Germany trip!

Fly Safe,
Steve R.

[Cletus]

The good news is, I test fired the turbine just now and it's fine!
Will order replacement parts when I get back from my trip!

[Intrepid175]

Excellent! At least the rebuild will be a relative non-event.

Have a safe trip!

Steve R.

[Cletus]

Thanks, hoping not to fall asleep in the course .....advanced tech support training on the Draeger Primus Anesthesia Machines

[Pinecone]

OUCH.

This is why I spool up in Normal, and go to Idle Up BEFORE lifting off.

[desertstalker]

Originally Posted by Pinecone

OUCH.

This is why I spool up in Normal, and go to Idle Up BEFORE lifting off.

Cant they put a soft start on a turbine ECU (should just be a matter of programming)?

Then you could do what all us electric folks do and do away with the normal mode completely.

[Intrepid175]

Originally Posted by desertstalker

Cant they put a soft start on a turbine ECU (should just be a matter of programming)?

Then you could do what all us electric folks do and do away with the normal mode completely.

It's not about a soft start. On the initial spool up, turbines can't accelerate fast enough from idle for it to be that big a deal. Cletus' problem didn't have anything to do with the engines ability to respond. He was simply in the wrong flight mode and wasn't running an aerobatic throttle curve. When he went inverted and pulled the collective down to hold altitude, the engine dropped off too and the picture at the beginning of this thread tells the rest of that story.

[desertstalker]

Originally Posted by Intrepid175

It's not about a soft start. On the initial spool up, turbines can't accelerate fast enough from idle for it to be that big a deal. Cletus' problem didn't have anything to do with the engines ability to respond. He was simply in the wrong flight mode and wasn't running an aerobatic throttle curve. When he went inverted and pulled the collective down to hold altitude, the engine dropped off too and the picture at the beginning of this thread tells the rest of that story.

Yeah I got that...

If the turbine has slow spool built in, then why not fly just from a idle-up curve? that way you know you are never going to have that issue. After doing something similar myself I start all my helis in idle 1 (lowish HS but no 0s anywhere), can you not do something similar for a turbine or is there a purpose to a normal curve i am missing (I know for nitros you often need to handle spool yourself, since the engine can accelerate fast enough to fry the clutch)?

[cbergen]

Do you start a Nitro in idle 1? How about a Gasser?

What you're missing is the need to start the engine at an idle. An electric motor is either on or off, it doesn't run at an idling RPM.

To get from an idle to flying RPM, you need the ramp up that a normal mode curve gives you.

Then when you're done flying, you want to bring the engine back to an idle before shutting it off. Again, the ramp from flying RPM down to idle is needed. Could you shut the Turbine down from Flight RPM? Sure!

But it's not recommended...

I also like to have 3 different Headspeeds, I use normal mode for low speed, precision hovering, ground work, etc. idle 1 is for basic aerobatics at a medium HS, those big loops and long rolls. Idle 2 is for stationary flips, faster maneuvers and high speed scooting around the sky. And Launch Takeoffs of course...

[Intrepid175]

Originally Posted by desertstalker

Yeah I got that...

If the turbine has slow spool built in, then why not fly just from a idle-up curve? that way you know you are never going to have that issue. After doing something similar myself I start all my helis in idle 1 (lowish HS but no 0s anywhere), can you not do something similar for a turbine or is there a purpose to a normal curve i am missing (I know for nitros you often need to handle spool yourself, since the engine can accelerate fast enough to fry the clutch)?

Well, in your post I initially responded to, you asked:

Cant they put a soft start on a turbine ECU (should just be a matter of programming)?

so that's why I said what I said.

As to what I think you'er asking above, the answer is sure, you can bring it into an idle up before lift off. How that will work out depends entirely up to how you set it up. Speaking for myself and how I set my models up, Normal mode is strictly for start up. I set throttle curves so the bird behaves itself and I can fly around in Normal mode but almost never do. Idle 1 is what I do 90% of my basic flying around in and is identical to Normal mode but the governor (if applicable) is active where it is not in Normal. If the bird doesn't have a governor, then the throttle curves are set to keep the engine from dropping all the way to idle as you suggest. The turbine machines I fly are setup for camera work so aerobatics are totally out of the question but on the Wren turbines, that don't have a governor, I do keep the minimum throttle up around 25 to 30%. It's a peace of mind thing for me and the bird hold rotor speed very well within the limitations that I fly it in. Whether or not that would have been sufficient to get Cletus out of the situation he found himself in, I have no idea. Idle 2 is not used on the turbines I fly for obvious reasons. On my personal birds, it's the full aerobatic mode with mirrored collective and inverted bell shaped throttle curves. Of course, any combination of the above, plus any number of combinations I've never throught of, can be done based solely on personal preferrence.

Fly Safe,
Steve R.

[rdlohr]

Man Cletus, that really sucks! Sorry to see it.

My normal mode allows me to spin up, but it has a flat pitch curve of -2, so you can never leave the ground. I made that mistake exactly once. I know I would have done it again so I programmed out the possibility.

Hope it goes back together without too much trouble.

Rick