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Author Topic: Propeller precession  (Read 5442 times)

Offline Ken Culbertson

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Re: Propeller precession
« Reply #100 on: September 20, 2021, 07:50:40 PM »
Here is the fun part: itís ok to put 1 oz in the weight box of the outboard wing, itís ok to put 1 oz of lead in the tail to balance the model. But to put 1 oz shut off system it is a dead weight!))
What does the receiver end of 2.4gh weigh?  The wires to the esc are thin.  Why can't the receiver and a small battery to power it BE the tip weight?  I have no clue if that could work but if.....

Ken
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Offline Trostle

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Re: Propeller precession
« Reply #101 on: September 23, 2021, 12:51:10 AM »

Quote from: jerry v on September 20, 2021, 07:09:08 PM

    Here is the fun part: itís ok to put 1 oz in the weight box of the outboard wing, itís ok to put 1 oz of lead in the tail to balance the model. But to put 1 oz shut off system it is a dead weight!))

What does the receiver end of 2.4gh weigh?  The wires to the esc are thin.  Why can't the receiver and a small battery to power it BE the tip weight?  I have no clue if that could work but if.....

Ken


If I read what Jerry and Ken have written, they appear to be complaining that an electronic device cannot be used to stop a motor on a stunt ship in flight.

For the record, Rule 2.6 in the Control Line Precision Aerobatics rule book states:

"2.4 GHz spread spectrum radio control signals may be used to control ... a one-time irreversible engine or motor stop function."

My apology to those if I misunderstood what they wrote.

Keith

Offline jerry v

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Re: Propeller precession
« Reply #102 on: September 23, 2021, 06:39:13 AM »

If I read what Jerry and Ken have written, they appear to be complaining that an electronic device cannot be used to stop a motor on a stunt ship in flight.

For the record, Rule 2.6 in the Control Line Precision Aerobatics rule book states:

"2.4 GHz spread spectrum radio control signals may be used to control ... a one-time irreversible engine or motor stop function."

My apology to those if I misunderstood what they wrote.

Keith
Keith,
Rules are good, reasonably  weighted  equipment is available , but how many pilots installed the motor shut off system on their PAMPA / F2B stunt ships? I donít know anybody who hasÖ Maybe it is a dead weight?))

Jerry
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Offline Ken Culbertson

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Re: Propeller precession
« Reply #103 on: September 23, 2021, 10:30:56 AM »

If I read what Jerry and Ken have written, they appear to be complaining that an electronic device cannot be used to stop a motor on a stunt ship in flight.
My apology to those if I misunderstood what they wrote.

Keith
You did miss my point.  I was considering the weight and where it could be placed and secondarily, not in my post,  could a non 2.4ghz device be on the plane in competition but not used.  If that were the case it could be used to stop a flight in a bad or dangerous situation resulting in a -0- score or a C/D ruling.  When was the last time anyone aborted a flight for any reason and got a score that still placed?

Electric PA has no need for a cutoff during competition, the timer does that just fine.  IC in general would LOVE one. It is the non-competition flights and the "emergency" use in competition that I am concerned with.  If the penalty for using one is to DQ the flight, that is OK.  If the penalty is to DQ the flier then that is not OK.  If simply having the plane equipped is a violation then this is all moot which the PA rules seem to do.  Simply having a non 2.4ghz electronic device on the plane is a violation whether you use it or not.

We are doing the same thing here we did with Spectra lines.  Focusing on a single solution to a problem that has many.

Ken

Having said all of that there appears to be several options within the 2.4ghz that just might offer even better options.  What if there was a Timer that could be programmed in flight.  RPM, gain, cutoff to let you actually trim the powertrain while in the air in one long flight instead of many short ones then disabled for all but cutoff and gear retraction in competition.  Now that is a pie I would look to the sky for!  And, all of it could be mounted in the outboard tip.  ZERO weight gain!


« Last Edit: September 23, 2021, 11:04:41 AM by Ken Culbertson »
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Offline Brett Buck

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Re: Propeller precession
« Reply #104 on: September 23, 2021, 11:02:01 AM »
Keith,
Rules are good, reasonably  weighted  equipment is available , but how many pilots installed the motor shut off system on their PAMPA / F2B stunt ships? I donít know anybody who hasÖ Maybe it is a dead weight?))

   Ultimately, 8 minutes for a 5:45 flight is enough tolerance that there is very little motivation to do anything different. Even 7 is plenty if you can get the engine started quickly. I haven't flown a tremendous number of FAI-rules practice and contest flights, I can't think of a single time I overran it, even on practice flights where we timed it to check.

        Brett

Offline Trostle

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Re: Propeller precession
« Reply #105 on: September 23, 2021, 07:11:18 PM »

"If that were the case" ---   "If the penalty" ---  "If the penalty"  ---  "If simply having"

Ken

"What if there"   ---


So many "ifs".  My head spins.  I guess I am getting old and cannot keep up.

Keith

Offline jerry v

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Re: Propeller precession
« Reply #106 on: September 23, 2021, 09:16:34 PM »
I was talking about engine/electric motor shut off system for emergency situations. For ďwet ď power to pinch the fuel line and for electric power to override the timer settings and turn the motor off.
Of course some pilots will see the opportunity to use the system for better score on landing.

Jerry
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Online Howard Rush

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Re: Propeller precession
« Reply #107 on: September 23, 2021, 10:46:09 PM »
Of course some pilots will see the opportunity to use the system for better score on landing.

One could do a cutoff loop.  No radio required.
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Offline Ken Culbertson

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Re: Propeller precession
« Reply #108 on: September 23, 2021, 11:06:46 PM »
I was talking about engine/electric motor shut off system for emergency situations. For ďwet ď power to pinch the fuel line and for electric power to override the timer settings and turn the motor off.
Of course some pilots will see the opportunity to use the system for better score on landing.

Jerry
Howard is right.  What is the difference in a kill loop and a kill switch.  The Kill Loop would look silly if you are using electric but I do the same thing by positioning the plane at the right height and speed through whipping when I get the 10 second cutoff warning from the timer.  As far as I am concerned, anything you do under the rules to gain an advantage is OK.

Ken
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Offline Mark wood

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Re: Propeller precession
« Reply #109 on: October 12, 2021, 10:34:55 AM »

Electric PA has no need for a cutoff during competition, the timer does that just fine.  IC in general would LOVE one. It is the non-competition flights and the "emergency" use in competition that I am concerned with.  If the penalty for using one is to DQ the flight, that is OK.  If the penalty is to DQ the flier then that is not OK.  If simply having the plane equipped is a violation then this is all moot which the PA rules seem to do.  Simply having a non 2.4ghz electronic device on the plane is a violation whether you use it or not.



Having said all of that there appears to be several options within the 2.4ghz that just might offer even better options.  What if there was a Timer that could be programmed in flight.  RPM, gain, cutoff to let you actually trim the powertrain while in the air in one long flight instead of many short ones then disabled for all but cutoff and gear retraction in competition.  Now that is a pie I would look to the sky for!  And, all of it could be mounted in the outboard tip.  ZERO weight gain!

There is an over reliance on the 2.4Ghz technology in the rules and it doesn't provide any better security than using a simple 833 Mhz Tx Rx device. The difference is that the 2.4 Ghz devices are intended for continuous data stream while most of the 833 Mhz devices are simply listening for a 128 bit code they have been bound with and only toggle an output on and off. This is inherently compliant with the intent of this rule. The rule truly should simply state a non reversible cut off device. I use one to operate my electronic "stooge" and I have a version using the other button to start / stop a timer. It's a simple interface to the timer. Of course this idea can be expanded to using the device additional buttons and associated bit toggling to do other things but again it is a simple non proportional control.
Life is good AMA 1488
Why do we fly? We are practicing, you might say, what it means to be alive...  -Richard Bach
The aerobatic airplane is a tool, a pencil, a paintbrush the artist uses to paint their aero art on to the tapestry air with. That art is the combined elements of figures drawn in space and time.  - M. Wood

Online Howard Rush

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Re: Propeller precession
« Reply #110 on: October 12, 2021, 01:31:03 PM »
You should never base the rules in a specific technology, like in this case.

That is correct.  Alas, this is not the worst violation of this principle in American control line rules.
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Offline Ken Culbertson

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Re: Propeller precession
« Reply #111 on: October 12, 2021, 02:53:50 PM »
I find it amusing that we always seem to come up with all of these rule change ideas just after the window for getting them passed is closed.  I am 100% in agreement with Lauri.  To me it is simple...."Any form of remote cutoff may be used as long as it is irreversible and cannot interfere with any other flier."  So if we all agree then it will be two years before we can use one.  Don't want to rush into anything that makes sense.

Ken
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Offline Mark wood

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Re: Propeller precession
« Reply #112 on: October 12, 2021, 03:19:44 PM »
I find it amusing that we always seem to come up with all of these rule change ideas just after the window for getting them passed is closed.  I am 100% in agreement with Lauri.  To me it is simple...."Any form of remote cutoff may be used as long as it is irreversible and cannot interfere with any other flier."  So if we all agree then it will be two years before we can use one.  Don't want to rush into anything that makes sense.

Ken

Ken I think we (people on the forum) have had this discussion previously on here and I was pretty much shut down. Ultimately, I'm not planning on worrying much about it. I'm not certain about my participation in competitions with any device which has a remote shut off on it. My current timer breadboard is far from readiness as it doesn't include any accelerometer input and I'm not sure I am ready to spend the effort to write the code and go through the development when I'm flying a Fiorotti device which works good. Should I happen to arrive with a device which is on my airplane and is in violation of the rules and I get disqualified for such device well, that speaks volumes and I'd probably never ever participate again. It's not likely that this will occur but it could. The point is that there has been intense opposition spoken here to such ideas and staunch vocal oppine that any device must be 2.4Ghz which is nonsense.
Life is good AMA 1488
Why do we fly? We are practicing, you might say, what it means to be alive...  -Richard Bach
The aerobatic airplane is a tool, a pencil, a paintbrush the artist uses to paint their aero art on to the tapestry air with. That art is the combined elements of figures drawn in space and time.  - M. Wood

Offline Ken Culbertson

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Re: Propeller precession
« Reply #113 on: October 12, 2021, 04:55:58 PM »
Ken I think we (people on the forum) have had this discussion previously on here and I was pretty much shut down.
To a point I agree.  It seems that "good" ideas need to come from the right source to have any traction but that is not why I am replying.

I just switched to the Fiorotti timer and I am hoping to get feedback from others using it as I try and figure out how to maximize it's features.  I have kept my "Trifacta" thread going primarily to provide feedback on the timer to Fiorotti.  I have flown the plane with both Nose Up and G-Force turned off and even with that it has been a pleasant surprise over the Hubin (which is great for what it does).  I am also getting used to logarythmic flaps at the same time.  Now that is an experience if you have never used them.  Any "rookie" tips would be appreciated.  I think enough people are using it that it would be nice to have a section here dedicated to it or maybe to active timers in general.

Ken
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Offline Brett Buck

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Re: Propeller precession
« Reply #114 on: October 12, 2021, 05:53:10 PM »
Sorry, this is not about precession.
I have asked this before and I'll ask it again:
Why do you require specifically the 2,4gHz in your rules? You should never base the rules in a specific technology, like in this case.

    Because that is the only form of RC permitted in CL General, and, they don't want to have to deal with impound. It's really not that hard to understand.

    Brett

Offline Mark wood

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Re: Propeller precession
« Reply #115 on: October 12, 2021, 06:17:07 PM »
Brett

There would be no need to impound the 833 Mhz devices as well. Once the transition to digital code format interference goes away. Once TX and RX have been "bound" there is no need to worry about other transmitters on the same frequency. It all falls under the open use by the FCC just the same as the 2.4 Ghz frequencies. There's others here more knowledgeable than I am on all of those regulations but basically it is unrestricted.

Here is the reason for being motivated. The 2.4 Ghz devices are intended to communicate digitally and pass data back and forth. This in turn creates a more complex requirement for the transmitter and receiver which drives the cost up. The lower frequencies can be used for this but typical. Generally the 833 devices transmits a single code which the paired receiver listens for. So a tx for 2.4 Ghz low end costs around $80 while a 833 Mhz TX can be purchased for $5. Likewise the receivers are $35 ish and $4 ish. There is no loss of security of the signal or so minor as to be insignificant.

If the rule simply said no proportional control allowed would cover enough of need.
Life is good AMA 1488
Why do we fly? We are practicing, you might say, what it means to be alive...  -Richard Bach
The aerobatic airplane is a tool, a pencil, a paintbrush the artist uses to paint their aero art on to the tapestry air with. That art is the combined elements of figures drawn in space and time.  - M. Wood

Offline Trostle

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Re: Propeller precession
« Reply #116 on: October 13, 2021, 12:35:24 AM »

Because that is the only form of RC permitted in CL General, and, they don't want to have to deal with impound. It's really not that hard to understand.

    Brett

To expand on what Brett just explained, the AMA Control Line General rules specifically states:  "The use of radio control to accomplish any control functions on Control Line models is specifically prohibited except as follows.  The use of 2.4 GHz (utilizing spread spectrum, 47 CFR Part 15) radio control to accomplish functions other than providing aerodynamic control of the model's elevation on Control Line models is allowed, but only to the extent and in the manner specifically allowed by the rules of the individual event."  The CL Precision Aerobatic rule was adopted to agree with the CL General rule on this matter.

If other radio control technologies are available to provide non "aerodynamic control of the model's elevation on Control Line models" without the need for frequency control/impounding transmitters, then maybe a rules change proposal would be appropriate to the Control Line General rules as well as the CL Precision Aerobatics rules.

Keith

Offline Mark wood

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Re: Propeller precession
« Reply #117 on: October 13, 2021, 07:47:19 AM »
Keith

First this divergence of the thread should move elsewhere. I think we recognize what the rule says and that is specifically what is objectionable to a number of us ( I thought I was alone). The fact that it restricts the technology to only the 2.4 Ghz devices. The other devices on other frequencies have just as adequate lack of interference and do not require impoundment. The specific rule for CLPA requires a non reversible function. In both cases the 833 Mhz devices meet the intent of the rule. Therefore, a rule change is in order. Unfortunately, this has come up outside of a rule cycle.
Life is good AMA 1488
Why do we fly? We are practicing, you might say, what it means to be alive...  -Richard Bach
The aerobatic airplane is a tool, a pencil, a paintbrush the artist uses to paint their aero art on to the tapestry air with. That art is the combined elements of figures drawn in space and time.  - M. Wood

Offline Ken Culbertson

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Re: Propeller precession
« Reply #118 on: October 13, 2021, 10:03:34 AM »
...... lack of interference and do not require impoundment"."
That, put into AMAeze should be the extent of the CL General Rule.  Let each branch deal with it from there.  Here may be the rub.  In order to fix the PA rule you are going to have to fix the General First.  I don't know if there is a provision to pass a change contingent on another change passing.  If not then there are 2 rules cycles.  Maybe in this case our current rule is adequate given a change to the general.  Personally I think remote motor kill is an extremely desirable thing to have,  especially for those lost soles still flying IC.  Not just for contests but for trimming and safety - you take off and something is wrong with the controls or you have a prop strike on takeoff and it snaps part of a blade off.  How many planes would be saved if we could abort immediately.  How many contests would run on time if we didn't have to wait for that guy that couldn't measure his fuel and was still flying when everyone else left for lunch or to simply take an attempt.  It just makes sense.

Ken
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Offline Mark wood

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Re: Propeller precession
« Reply #119 on: October 13, 2021, 11:09:20 AM »
Personally I think remote motor kill is an extremely desirable thing to have,  especially for those lost soles still flying IC.  Not just for contests but for trimming and safety - you take off and something is wrong with the controls or you have a prop strike on takeoff and it snaps part of a blade off.  How many planes would be saved if we could abort immediately.  How many contests would run on time if we didn't have to wait for that guy that couldn't measure his fuel and was still flying when everyone else left for lunch or to simply take an attempt.  It just makes sense.

Ken

EXACTLY...!!!

This is directly and specifically my number one drive to have a remote on / off feature in my timer. To restrict such a device to an expensive limitation is counter productive to safety.

Life is good AMA 1488
Why do we fly? We are practicing, you might say, what it means to be alive...  -Richard Bach
The aerobatic airplane is a tool, a pencil, a paintbrush the artist uses to paint their aero art on to the tapestry air with. That art is the combined elements of figures drawn in space and time.  - M. Wood

Offline Ken Culbertson

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Re: Propeller precession
« Reply #120 on: October 14, 2021, 06:37:26 AM »
The only problem is that those who cannot measure fuel or set the needle will probably be the last to adopt the system. And they don't need extra complications in their power system.
 
As I wrote earlier, it's not really that important in contest use, but really nice when trimming and practicing.
But then, we could have it like in some f'ing X-Factor and let the judges stop the engine if they feel it's not worth watching.. That would make contests shorter :)
L
I have seen some world champions have an overrun.  We had a contest this spring where the entire advanced class save one overran along with 2 experts.  It is not the overruns that gum up the works it is the attempts when the weather baffles even the best of us and the smart ones take an attempt.  I would support giving the judges a 4-10 shotgun if it would bring down some of those never ending attempts. VD~

This is mostly an electric issue anyway.  Most of the weight issues would be eliminated by enhancements to timers.  Some may already be considering it for the reason you champion - trimming.  I am going to look into the RDT's available.  I have an idea they could be made removable until we can get some sensible rules.

Ken
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Offline Brett Buck

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Re: Propeller precession
« Reply #121 on: October 14, 2021, 11:20:30 AM »
Keith

First this divergence of the thread should move elsewhere. I think we recognize what the rule says and that is specifically what is objectionable to a number of us ( I thought I was alone). The fact that it restricts the technology to only the 2.4 Ghz devices. The other devices on other frequencies have just as adequate lack of interference and do not require impoundment. The specific rule for CLPA requires a non reversible function. In both cases the 833 Mhz devices meet the intent of the rule. Therefore, a rule change is in order. Unfortunately, this has come up outside of a rule cycle.

    This has been in there for at least 8 years - 4 entire rules cycles -  and there was a fairly extensive discussion of the entire topic here when I wrote the proposal about it for CL Stunt something like 6 years ago.

    For goodness sake, this happens every two years - no one pays the slightest attention to the rules cycle, despite it being posted, for more than a year, and despite Keith and others keeping everyone informed here, and lots of discussion threads. Then the vote results are announced, and  sometimes the very next day, someone starts complaining that "they changed the rules!" or "they didn't fix the rules!", "or that was stupid they should have said THIS...!" or some variant.

    When the first proposal for Spectra lines was made, and failed (for perfectly obvious reasons), literally the next day someone - who admitted that he had never heard there was a proposal at all and had never made a single peep about the topic - said they "might just as well quit CL". Over the failure of a proposal they had never heard of until afterwards?

    You know why the rules didn't change? Because no one made the slightest effort to change them, or even suggest they be changed, or even have a comment about it either way. If you don't do anything, then nothing is going to happen, or it will happen in a way you don't like.

    I would also note - the alternative to 2.4 GHz is not some other frequency - it is *no RC at all*. To be honest with you, I would support a change to CL General to disallow any form of radio or other EM emissions in CL, as not conforming with the idea of "Control through Lines". I am seriously considering removing the current rule for CL Stunt and just disallowing it completely.

      Brett

Offline Mark wood

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Re: Propeller precession
« Reply #122 on: October 14, 2021, 11:42:36 AM »


    I would also note - the alternative to 2.4 GHz is not some other frequency - it is *no RC at all*. To be honest with you, I would support a change to CL General to disallow any form of radio or other EM emissions in CL, as not conforming with the idea of "Control through Lines". I am seriously considering removing the current rule for CL Stunt and just disallowing it completely.

      Brett

Well, some of us have not been around this forum and have been participating in other activities. So, give us a break and allow us to be ignorant. By all means disallow any kind of RC to be spiteful which is certainly a solution. Taking such a stance is not very becoming and I realize I am particularly good at soliciting such responces. However, it is much simpler than that, when the cycle comes around again, simply remove the reference to 2.4 Ghz and replace with transmitter and receiver compliant with FFC regulations for open use which will not cause interference with others. In the specific section for CLPA simply state no proportional control of engine or electric powerplant allowed.
Life is good AMA 1488
Why do we fly? We are practicing, you might say, what it means to be alive...  -Richard Bach
The aerobatic airplane is a tool, a pencil, a paintbrush the artist uses to paint their aero art on to the tapestry air with. That art is the combined elements of figures drawn in space and time.  - M. Wood


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