Flying behind the power cure

All_In

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always do know that you have a good heart.
Thank you for your good advice to John to get flight instruction and learn to fly the gyro.
Marion

Marion after talking to Dave today he said the oddest thing to me. That he was afraid that people would read this and actually train themselves!

This thought had never occurred to me and would be like reading all the books needed for a degree in college and have many unanswered questions and NOT GO GET TRAINING in any subject if only too ask the unanswered questions.

This is why your statements of John getting training is so battling to me!!! How did I give anyone that idea! I would never get the answers to my questions from MYSELF and have a fool for a teacher in any subject! I seek out the best of several CFI's during my training in anything I learn even in college. I've never done that and assumes everyone would get training form the best CFI's and not self train!

Please understand I have not and will not self train. I have and will continue to get training from the best I can and will not self train in ANYTHING from diving to race car driving I just read all the books before I start!

I do not even know how you or anyone could have thought I would self train in any area! I'm stupid but not an complete idiot to do as you suspect I would. But at least I now understand what you assumes I was doing by writing this!
 
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All_In

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Bloodyell, talk about muddy water.

Its much easier to undertstand if you keep it simple.
1, flying slow, level, nose high at WOT isnt flyn behind the curve, its just flyn slow.
2, you dont fly wen your behind the curve, you sink.
3, your not in trouble if your not on full throttle.
4, your not in trouble in a full power sink either, untill you run out of altitude.

Good one Birdy. Will add this to the top paragraph where I start out by explaining how to prevent the problem in the first place!!!
Thank you!! U-ROCK!!
 
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All_In

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Careful, Birdy.

If less power is required to go faster, you’re on the back side of the power curve.

That’s a negative slope and all things with negative slopes are unstable.

In the case of a gyro, it’s speed instability.

In the case of semiconductor devices, things with negative slopes –less current with more voltage- oscillate. The transmitter in radar speed traps is a negative resistance device called a gunn diode.
Thank you Chuck I always learn from your posts!!
 

All_In

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"I'm not going to attempt to edit that whole piece for you, but I can tell you my eyes screeched to a halt when I saw this:
Quote:
Originally Posted by All_In View Post
... This is usually because the blade angle of attack and your pitch is too high with the power setting you have...

Blade angle of attack is an extremely complicated matter in gyroplanes, and far messier than the counterpart notion for a fixed wing. The angle of attack on a blade is different at every spot along the span because the net airspeed is different. Combining rotational speed (high at the tip and low near the hub) with forward translational motion adds up to a different vector at each station along the blade. And that's only a slice of the problem; as the blade rotates around the hub, the translational component is different for every position of the blade. Toss in some flapping, and it becomes silly even to talk about "the" blade angle of attack as if there were one such thing.

In a fixed wing, a bit of twist might be the only complication to consider, but the rotation of the blades in a gyro makes this no simple matter.

The pitch angle of the rotor disc with respect to aircraft's direction is much easier to envision and describe and will suffice in many contexts.
"

Brilliant post. Great point, well explained.
This is a great post and a little advance for this topic but going to add it to the end for those like me who just wish to learn all they can.

U-ROCK Bro!!
 
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All_In

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Hey John, just curious, you said in post 49 "ready to solo" what does that mean:confused:? have you been signed off to solo? Did Mike sign you off?. If so, can't wait to see you flying your gyro at ROTR.:)

Hi J
I could have been signed off for solo. However I told him that I do not have a ride to keep up my skills yet and by the time I do I may not only be rusty but forgot things.
So to keep from SELF TRAINING as my new toy is sitting in the hanger calling to me to fly her and just because I'm signed off is not a good idea until I have my ride flying to keep my skills up right after training.

As I've discovered that every CFI has a little different way of explaining things this will be my forth and a new instructor to me but have contacted him to do it at ROTR's. If he cannot make it then I will select another and hope to be signed off for solo when I leave even if it means staying for over a week after like you, your cousin and I did with Micheal last year.
 
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j bird

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Thanks for the update John, I sure hope it works out for you this year.
 

All_In

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.

I am more interested in what is the best way to recover ? .... if someone can explain it in one sentence please .

Other than abort the takeoff could this guy have done anything to save himself once he was in the air ???

http://www.rotaryforum.com/forum/showpost.php?p=630721&postcount=1

thanks

I would have looked for another flight route at a slight angle.
Here is what I saw available to the left but I suspect that a better path not shown in the video was to the right as it seemed to me the hill was sloping down more on that side to a valley I suspect. However it takes a long time and experience in flying to not fixate on taking off straight out so I may have done the same thing when I only had a few hours in FW's or any aircraft. I do look for the way out every new type and all aircraft I fly even the gyro the very first time I flew with an instructor.

Here is what I wrote in the thread on that crash.
"After the even quarterbacking it would been better to have turned to the left shortly after takeoff @0.42 and flown over the fence level off gaining airspeed then only a slight incline and through the gap between the Row of trees and the one small tree with space enough for the rotors to fit though but he was climbing enough for the blades to have gone over it. There were no large trees or building to the left and maybe even the right offered a way out after take off.

By 0.42 you should be able to tell your not climbing enough to make it over the trees in the front and been looking for the lowest clear exit it appears to be only a 20 degree turn to the left @0.42 of the video... Exit stage left in this case. Maybe right too we cannot see in that direction and it may have been down hill. "
 
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C. Beaty

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All_In

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Thanks for the update John, I sure hope it works out for you this year.
Thank you J.. If I can get her finished and registered this year I fly the blades off her everyday after solo!
 

Vance

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Try and focus on all the takeoff and landing accidents and not on any other event and it will help us be on the same page.
The last video we saw he started out not behind the power curve until he had to increase his angle of attack to get over the tree's then he got behind the power curve. If he had started out behind the power curve when he first lifted off I'm sure he would have stopped. So you do not need to think of all the exceptions as the the one above.

If you are speaking of the accident in England on the grass field; in my opinion it started when he intentionally rotated and lifted off with too little air speed. This is an example of why the attitude at lift off is so important.

I can see him try to rotate several times before he eventually does. I don’t see the angle of the disk decrease as lift off approaches as it should in a normal takeoff.

When the nose does come up there is no apparent effort to keep the nose wheel near the ground as described in the POH.

It appears to me from the nose up attitude that he is flying well behind the power curve.

He comes off the ground with the nose high too slow to climb out well. As things aren’t working out he keeps the cyclic back and slows until he descends to the ground. It appears to me he never releases back pressure and if anything is still pulling back further as the ground rushes up to greet him.

It appears to me the aircraft was nowhere near Vx at any time in the flight.

In my opinion this is an all too common accident for low time pilots and exactly what you appear to be describing in “flying behind the power cure”. The pilot appears to be trying to pull the cyclic back for altitude and the further back he pulls it the slower he climbs until he gets below the minimum level airspeed at full power and begins to descend.

I teach people to anticipate the nose wheel coming up as the rotor rpm and indicated air speed builds and teach students to allow the cyclic to come forward to lift off at the proper attitude when the gyroplane is ready.

When a student does not anticipate the nose coming up in The Predator and bounces the tail wheel on the runway he will hear from me; “cyclic forward to pick up airspeed.” I repeat this until either the student brings the cyclic forward of I take the aircraft controls. A few of these nose high lift offs are common no matter how I explain the takeoff procedure. Most people learn quickly to anticipate the nose wheel coming up and learn to allow the cyclic to come forward before the nose gets very far off the ground.

If this take off procedure is done properly in The Predator she will usually lift off at 45 to 50kts depending on conditions. If she lifts off below 30kts climb out will be leisurely until we reach at least 40kts of indicated air speed.

At Santa Maria there is nothing to hit for over 8,000 feet so it is not as intimidating as the grass field in the video.

This pilot in the video appears to me to have forced the “rotation” and never recovered airspeed after the premature, nose high lift off AKA flying behind the power curve.

It appears to me he eventually slows below a speed where he can sustain flight at full power.
 

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Vance

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All_In

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Yes Vance I think we are talking about the same takeoff. That is one of the most excellent analysis of the takeoff I've read. I missed many of the indicators and learned what to look for next time from you excellent description.
I care little about being right and only want to learn the correct answer!!!
Thank you so much for posting and helping me to learn I understood every word of that post. I have learned a great deal from you over the years!! U-ROCK!!!

Unless there is an obstruction at the end of the runway I always use a short field takeoff proceedure to gain airspeed before I start climbing out so it's never happened in anything I fly.
 
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Gyro28866

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John:
Them biggest problem is your machines have become educated; keep them illiterate and don't let them read the manual. If they don't know they are not supposed to be able to do it, then they will.
I convinced my Dominator it is really a Dumbinator!
How slow can you go?
https://youtu.be/XVLfGkosyFk
 

birdy

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If less power is required to go faster, you’re on the back side of the power curve
But youll be on the flyn side, not the sinkn side.


I would also disagree that your statement 3 is always true. You just may not know it until you throttle up and not enough happens.
Paul, wot are you do,n f***n around on the limit if you dont know when your close to it?
 

All_In

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John:
Them biggest problem is your machines have become educated; keep them illiterate and don't let them read the manual. If they don't know they are not supposed to be able to do it, then they will.
I convinced my Dominator it is really a Dumbinator!
How slow can you go?
https://youtu.be/XVLfGkosyFk

Good advice... You guys crack me up!
 

bryancobb

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That`s The FACTS !!

That`s The FACTS !!

If less power is required to go faster, you’re on the back side of the power curve


You can`t put it any clearer ! Very accurate and sunccinct.

Your earlier post (below) could not be more INCORRECT. It puzzles me why you made two posts that contradict each other ?
1, flying slow, level, nose high at WOT isnt flyn behind the curve, its just flyn slow.
2, you dont fly wen your behind the curve, you sink...
 
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thomasant

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Let's go to the Graphs

Let's go to the Graphs

Here's the graph of the Power reqd/Power available and the Rate of climb and descent at Full throttle from the FAA Gyroplane Handbook.

From 20 to 45 mph, less power is required for straight and level flight (Commonly referred to as behind the curve). Conversely, more power will be required for lowering speed from 45 to 20 mph.

At 40 mph, minimum power is required for level flight and minimum sink rate in glide (Minimum drag). This speed gives the best Angle of climb Vx. This is also the speed for best endurance (Max time airborne for least fuel burn).

At about 45 mph, best L/D ratio and gives best Rate of climb Vy. This is also the speed for best range (Max distance travelled for least fuel burn).

Below 20 mph, and above 85 mph gyroplane will descend at WOT.

The speed below 20 (Minimum speed for level flight at full throttle) is where the pilots crash on take off.
 

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Gyro28866

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Anthony:
Do I understand this correctly?
Below 20 mph, and above 85 mph gyroplane will descend at WOT.

Once again, I must have a Dumbinator!
With two fat boys last year at Bensen Days; at WOT my Domiator was showing an IAS of 115 mph; to slow it down, I initiated an enroute climb of a few hundred fpm. This slowed me back to VNE of 105 and an IAS of 105. BUT it was ASCENDING not Descending.
and for slow flight; watch my Gopro vid and explain this:
https://youtu.be/XVLfGkosyFk

I must explain: last year my carb jetting was not happy and at 1/2 to 3/4 throttle settings, my EGT's were going through the roof. The only way to cool them down was to open it up to WOT and they would instantly cool back to the 1075 to 1100 range.
 
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