HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Mar 07, 2014, 02:17 PM
Chuck 'Em and Chase 'Em
Fly2High's Avatar
United States, NY, Plainview
Joined Aug 2005
8,092 Posts
More interesting thing posted back in 2009 about height limiting equipment:

http://www.rcgroups.com/forums/showt...=altitud+limit

Post #8
Quote:
Quote:
Originally Posted by DingoII View Post
Now a serious question to the "fathers": existing BMFA, Slovakian, etc. rules call for recording devices enabling subsequent checks whether or not the pre-set height has been exceeded. This CAM is just a simple switch with no recording capability (which is IMHO exactly what most of the people want). So, is there any solution to that? I see two - either dual rulesets, or deleting the "recording requirement" from the existing (European) rules. Is there any other option?
Jan
I am not one of the "fathers" but have been enlisted as one of the supporters. Many people have criticised the Height limiter rules because of zooming and other things. Also the early height limiters evolved out of loggers, just like the early energy limiters, so the recording comes for free.

But for fun and club use I don't see why the rule should not simply be ignored/suspended and a simple limiter used. The contest director can say that if anyone seems visually to be climbing too high then he must fit a logging one, maybe that will be enough dissuasion!

But if you make it to the USA team for a World Championship in Romania then you may have to save up for a pukka $100 logging one.
Post #9

Quote:
Quote:
Originally Posted by George Shering View Post
But if you make it to the USA team for a World Championship in Romania then you may have to save up for a pukka $100 logging one.
Hi George,

Being an European I am sure I will not make it to the USA team

Please see http://www.rcgroups.com/forums/showt...137247&page=38, post 559. This is what we have actually concluded over here as well. If the zooming is to be prevented/limited then some additional technical rules (limitation of power, power/weight ratio, etc.) should be introduced. At least I think so.

Jan


Post #10

Quote:
Quote:
Originally Posted by DingoII View Post
Hi George,

Being an European I am sure I will not make it to the USA team

Please see http://www.rcgroups.com/forums/showt...137247&page=38, post 559. This is what we have actually concluded over here as well. If the zooming is to be prevented/limited then some additional technical rules (limitation of power, power/weight ratio, etc.) should be introduced. At least I think so.

Jan
The fact that there has been virtually no power limit set, if you use a limiter/logger in 200 meter comps, is in my view a weakness in the rules.

Accepting that they will negate zooming etc, it does not prevent a model using excess power to penetrate upwind, whilst the power is on, then climbing to trip the switch at 200 meters.Why would want to get to 200 meters in times of say 10 seconds, if it were not to take advantage of
this fact? Plus it allows in expensive F3j type models, which could not compete before with the old weight limit of 2 kilos for max 400watts of power.

So it will probably end up going the way of F3j, with limited appeal

Using the old 200 watts per kilo method, this was not really possible, with a standard setup, as you needed that to get to altitude.

It should be noted that the switches are or were not infallible, in that on two occasions at the same comp, that I know of they failed to trip at the correct height & on another, the flyer in question had failed to clear the log before flying, therefore the log would not have recorded his comp flights as it was full at the time. No checks were done at the end of said comp, as everyone wanted to get home.

The main idea of all this kit is that it makes it easier to set up a model, but the guys who know the score will use the max power, to gain the advantage that it gives. Also the organisers think that it will absolve them from checks on model power, which was claimed to be difficult & dangerous

But if checks are NOT done at the end of a contest how are you to know whether or not the comp was legal.


So having a switch that has a log would be the only way to check out the heights reached.
Essex BOF is online now Send a private message to Essex BOF Find More Posts by Essex BOF
Very interesting stuff
Fly2High is online now Find More Posts by Fly2High
Reply With Quote
Sign up now
to remove ads between posts
Old Mar 07, 2014, 02:55 PM
Proud member of LISF and ESL
LI, New York, USA
Joined Mar 2003
24,334 Posts
You have done some great research.

So, let's look at that first PoleCat ALES contest.
http://www.rcgroups.com/forums/showt...d+limit&page=3

I will note that, based on the rules posted for that contest:
http://www.rcgroups.com/forums/showa...8&d=1265222781

Altitude Limited Electric Soaring:
Objective - To provide a Man-On-Man (MOM), electric launched, thermal duration soaring
event with a consistent launch altitude for all competitors


OK, what does that mean? The rules define what it means.

Launches will be accomplished by the competitor’s on-board electric power system and will
begin within a starting launch window,
- The launching motor run will be limited by a 30second timer or 200meter launch altitude,
whichever comes first. (A list of acceptable altimeter/timer switches is attached).


So, according to the rules from that contest, a consistent launch altitude is DEFINED as the point at which the motor cuts off. Some may wish to interpret that as something else but the rules very clearly define a uniform launch altitude as being a uniform motor cut off, not final aircraft altitude.

This is a perfect parallel to the LSF/AMA soaring rules that define the maximum winch line that can be used, not the maximum altitude of the launch. As designed, ALES perfectly paralleled winch based TD contests by limiting the length of the launch, not the height of the glider. There are zooms in TD and zooms were allowed in that ALES contest, based on the rules.

In other words this ALES contest was an LMR to a specific altitude rather than a specific time.

Later attempts to change ALES into something else resulted in today's rules.
aeajr is online now Find More Posts by aeajr
Last edited by aeajr; Mar 07, 2014 at 03:22 PM.
Reply With Quote
Old Mar 07, 2014, 03:42 PM
Chuck 'Em and Chase 'Em
Fly2High's Avatar
United States, NY, Plainview
Joined Aug 2005
8,092 Posts
I see what you are saying Ed but taken the RCSD article (http://www.rcsoaringdigest.com/pdfs/...SD-2010-01.pdf) and the fact that Polecat's first set of rules had the following too:

Quote:
The CD may enforce a possible violation of the launch height by requiring that a contestant
re-launch his plane with a self-contained altimeter to verify compliance with the launch
target.
Why would they worry about a launch height violation if everyone had a ALS that guaranteed cutoff at the particular height?

There are plenty of other posts before the creation of ALES indicating that they did not think the power systems would exist to allow for running and then attaining 200M within 30 sec.

There are plenty of pilots who posted concern about zooming in 2008-2009.

Starting on page 2 of Zlog thread
Neil Stanton (who was instrumental in getting this going in England) ha some nice ideas about zooming
http://www.rcgroups.com/forums/showt...d+limit&page=2


What I find interesting is even Randy had concerns:

ZLOG page 1 above
Quote:
What stops someone with an "arc welder" from doing 90mph at cutoff so they affectively zoom another 200-300 feet higher than the lower powered models?

Randy
I would be surprised that it wasn't a concern but maybe they felt current equipment couldn't do it and that 30 seconds forced you to just climb or in order to do it, would be too heavy and therefor no one would do it?

Not sure. Still interesting history
Fly2High is online now Find More Posts by Fly2High
Reply With Quote
Old Mar 07, 2014, 05:20 PM
Proud member of LISF and ESL
LI, New York, USA
Joined Mar 2003
24,334 Posts
Frank, look at the title:

Rules for Height Limited eSoaring
Compiled from eSoaring.net <http://www.esoaring.net> - UK
and
British Model Flying Association <http://www.bmfa.org> - UK

These are not USA rules. These evolved into F5J, not USA ALES. F5J is sited in the article.

As for a concern, pick any topic. Someone will have a concern, so the fact that someone posted or wrote about something changes nothing. Someone is always concerned about something.

The rules are what matters, not what people might have been concerned about. And whether there is a method to be in compliance and a method to measure compliance. F5J provides both. Even at that early time:

(b) Model processing - initial
Before the start of the contest the CD (Contest Director), or
their representative shall ensure that the model is fitted with an
approved height limiting switch, which is set to cut all power to
the electric drive motor so that the model aircraft completes its
launch phase at a height above launch level of 200 metres.
To facilitate processing, all limiting switches must be easily
removable and/or easily accessible for checking and log
downloads
.

The device must be designed to conform to a launch height spec and must be certified/approved to meet the requirements.

In order to gain approval, any height
limiting switch must demonstrate that it
will consistently enable an electric glider,
when operated within the rules of the
competition, to finish it’s launch phase
at a height of 200 metres, plus or minus
8 metres. This requirement must be met
whether or not the unit incorporates an
“antizooming” feature.



The F5J rules in the article also allows re-launches, like F3J.

USA ALES rules then and now provides for none of this.

If you are trying to make a point, I am afraid I am missing it. The UK rules, back in 2010, do a better job of defining the task, how it will be measured, how it will be audited and how the devices will be certified that ALES does today.

Current F5J rules do a really good job.
aeajr is online now Find More Posts by aeajr
Last edited by aeajr; Mar 07, 2014 at 05:46 PM.
Reply With Quote
Old Mar 07, 2014, 06:02 PM
launch low, fly high
New Zealand, Hawke's Bay, Havelock North
Joined Dec 2004
1,816 Posts
Quote:
Originally Posted by aeajr View Post
Joe, how does this launch profile violate the intent or the rules of ALES as they stand today. I don't understand your statement. Can you be more specific?

I just reread the ALES rules and see nothing that defines a launch profile other than this passage.


3. Launch direction will be determined by the CD or his/her designated Launch Supervisor. All pilots will launch in the direction specified. Pilots may re-direct their flight path during launch provided this is done in a safe manner and does not interfere with the other launching pilots. A collision or other significant disturbance to another launching plane due to a pilot re-directing his flight path will result in 0 points for that pilot for that round,


Only launch direction is defined. Pilots are explicitly allowed to redirect their launch paths. So where do you read that run, climb, run, climb .... is a violation of any spirit or letter of the rules and why would you call this "gaming"? Seems perfectly acceptable as I read the rules.

I welcome your comments as I don't understand your statement.
I will attempt to put my rationale in simple terms for edification. I really hope that you are not being intentionally obtuse here...

The rules state that launch height is to be limited to a consistent level for all contestants. That is very clear. Some have been questioning the definition of "launch height" and have been arguing that the definition should be purely that of the height at which the motor is disabled.

I am of the opinion that launch height should be the final height achieved after the motor is shut off and the plane reaches a typical equilibrium airspeed. This is similar to the launch height measurements from string launch. In terms of string launching, people do not claim that the launch height is the height at which the parachute is released from the plane, but rather the height that the airplane achieves after the zoom portion of the launch is completed.

In a string launch the plane dips down at the top of the tow to convert line tension to kinetic energy, then pulls up to a high angle trajectory to convert the kinetic energy to altitude. If I was watching a string launch I would strongly suspect that the pilot is executing a "zoom launch" when dipping down and accelerating, then climbing quickly after releasing the chute so as to increase the launch altitude as compared to just reducing the line tension and letting the parachute float off of the plane.

The electric portion of this analogy has the plane reduce the climb rate to accelerate to a high speed and then cross the motor cut-off height at a high airspeed to increase the launch height above the motor cut-off height. This launch profile allows for a launch height (as most rational people define "launch height") to be considerably higher than the motor cut-off height. When I see a plane execute this type of launch profile I have a strong suspicion that the competitor is intentionally subverting the rules (aka "cheating"). When one knows the size of the aircraft being launched, one can make a rough evaluation of the launch height achieved. If my RED 4 meter aircraft is 25% bigger than his RED 4 meter aircraft at the conclusion of the launch, I can make the assessment that either I have a defective altimeter, or that the other competitor is launching to an altitude that may be more equal than my launch altitude (hat tip to Animal Farm).

The concept is rather simple from a physics perspective (increased kinetic energy at motor cut-off adds to the total energy available). Let me know if you have any difficulties in the understanding of the above concept.


My concern about ALES (without enforcement of the anti-zoom clauses that are currently written in the rules) is that the event will evolve towards high powered "arc-welder" aircraft as the optimal choice. That doesn't mean that all competitors will choose this approach, similarly as not all competitors at a string launch event are flying RED 4 meter sailplanes. From what I understand, this evolution is counter to the basic premise in ALES of a fair/equal starting height for all competitors.


Add: for clarification purposes, the below rule in ALES is the pertinent rule in this case:

Quote:
5. 'Zooming' is defined as using kinetic energy
(speed) stored in the plane during the launch to
exceed the designated launch height by more
than 10%. Zooming will be considered in
violation of the intent of the altitude limiter rule
and the Contest Director may assign a score of
zero to the violator for that round.
Joe W is offline Find More Posts by Joe W
Last edited by Joe W; Mar 07, 2014 at 06:11 PM.
Reply With Quote
Old Mar 07, 2014, 09:24 PM
Registered User
so. cal.
Joined Jan 2006
2,684 Posts
Ahhh, memories of the "gorilla winch", I love zooms...
s2000 is online now Find More Posts by s2000
Reply With Quote
Old Mar 07, 2014, 09:33 PM
Chuck 'Em and Chase 'Em
Fly2High's Avatar
United States, NY, Plainview
Joined Aug 2005
8,092 Posts
With a simple search I have found posts for F5J in the electic sailplane thread at least as far back as 2006.

http://www.rcgroups.com/forums/showt...5j#post4864004

But you are right that it wasn't vote for acceptance to FAI until 2011 I think I recall but I could be wrong.
Very interesting history of electric competition.

As for my comment it was based on the fact that ALES came from the British rules.

My question was why did polecats need a clause about height violations when they all used an ALS?

Shouldn't be needed so was the rule pertaining to zooming?


But like you said the rules are what is important and the current rules state a desire for a uniform launch height and zooming is to be prevent and optionally penalized.
Fly2High is online now Find More Posts by Fly2High
Last edited by Fly2High; Mar 07, 2014 at 09:44 PM.
Reply With Quote
Old Mar 07, 2014, 10:33 PM
Proud member of LISF and ESL
LI, New York, USA
Joined Mar 2003
24,334 Posts
Joe W,

Thanks for you clarification. I now better understand your post and your position on the subject.


Friends,

I think this has gone on long enough for me. I am going to unsubscribe from the thread. I don't see any real value from further discussion and I don't think I have anything more to add.

I hope to see you all on the flying field, whether it be ALES or TD.
aeajr is online now Find More Posts by aeajr
Reply With Quote
Old Mar 08, 2014, 04:43 AM
turn, turn, turn.
Athol, Massachusetts
Joined Oct 2005
10,291 Posts
I'm pretty sure that if I'm going straight up at a thousand watts in my topaz, I mean straight up... I will lose more in the stall that I gained in the zoom.

it's a bold statement, but I will check with my Atlis 4, and report back..
Kenny Sharp is online now Find More Posts by Kenny Sharp
Reply With Quote
Old Mar 08, 2014, 06:54 AM
Flying = Falling (Slowly)
dharban's Avatar
Tulsa, OK
Joined May 2004
2,597 Posts
At the risk of offending the religious beliefs some may have about scoring programs, I have a practical solution to how to deal with overlaunching in an environment where contestants are required to measure their launch altitudes (perhaps championship level contests).

GliderScore is a free standing scoring program that has the flexibility to score a very wide variety of glider comps including ALES and F5J. In examining it this morning I discovered that in the ALES mode it is possible to incorporate a launch altitude penalty similar to the F5J penalty, but structured for ALES type flying.

In F5J flying a penalty is assessed based on deducting 1/2 point per meter of launch up to 200 meters and 3 points per meter of launch in excess of 200 meters.

It turns out that in the ALES mode it is possible to configure the altitude penalty to "blend" in with the way we fly ALES -- for example, no penalty for launches up to 220 meters and maybe 5 points per meter of launch in excess of 220 meters (or whatever might seem fair).

Incorporating a penalty system like this with GliderScore into a contest is very simple. GliderScore prints individual round cards for each contestant which, in this case, would provide for entering flight time, landing score, and launch altitude. Each card is turned in and those three parameters are entered into the computer. The computer does the scoring. That's it.

The sum total of the added complication is 5 or 10 seconds more at the landing zone to write down the launch altitude and 2 or 3 seconds more at the scoring table to enter it into a computer -- plus the need for altitude switches which can report launch altitude.

Today, this very day, the technology exists to do this without any further effort on the part of contestants or contest organizers.

Happy Landings,

Don

BTW: It might be possible using this protocol for organizers to "exempt" certain planes (maybe foamies or novice planes, for example) from having to report launch altitudes. Those planes would simply enter a zero as launch altitude
dharban is online now Find More Posts by dharban
Last edited by dharban; Mar 08, 2014 at 07:22 AM.
Reply With Quote
Old Mar 08, 2014, 06:59 AM
Flying = Falling (Slowly)
dharban's Avatar
Tulsa, OK
Joined May 2004
2,597 Posts
Quote:
Originally Posted by Kenny Sharp View Post
I'm pretty sure that if I'm going straight up at a thousand watts in my topaz, I mean straight up... I will lose more in the stall that I gained in the zoom.

it's a bold statement, but I will check with my Atlis 4, and report back..
Kenny, typically a stall for which no real effort is made to recover will account for about 15 meters of lost altitude. Any reasonable effort to recover will reduce that to around 5 meters and with practice, it is possible to lose less than that from your peak altitude.

Happy Landings,

Don
dharban is online now Find More Posts by dharban
Reply With Quote
Old Mar 08, 2014, 07:21 AM
turn, turn, turn.
Athol, Massachusetts
Joined Oct 2005
10,291 Posts
Quote:
Originally Posted by dharban View Post
Kenny, typically a stall for whichis made to recover will account for about 15 meters of lost altitude. Any reasonable effort to recover will reduce that to around 5 meters and with practice, it is possible to lose less than that from your peak altitude.

Happy Landings,

Don
thanks Don.

I'm wondering if you have a prediction on what my zoom will be going straight up... as you know, it is a fairly draggy airframe, and it seems that going straight up would give me the least altitude.
Kenny Sharp is online now Find More Posts by Kenny Sharp
Reply With Quote
Old Mar 08, 2014, 09:09 AM
Turn down for what?
rdwoebke's Avatar
United States, IN, Indianapolis
Joined Feb 2004
14,831 Posts
Quote:
Originally Posted by aeajr View Post
I think this has gone on long enough for me. I am going to unsubscribe from the thread.
This thread is setting some kind of record for the number of times people have said "last thing from me on this" or said they were unsubscribing.

Ryan's secretary
rdwoebke is online now Find More Posts by rdwoebke
Reply With Quote
Old Mar 08, 2014, 09:37 AM
Registered User
so. cal.
Joined Jan 2006
2,684 Posts
+1. Now we are getting somewhere
s2000 is online now Find More Posts by s2000
Reply With Quote
Old Mar 11, 2014, 04:26 PM
TEAM FUTABA TEAM DURALITE
mithrandir's Avatar
Joined Nov 2004
742 Posts
electric ALES Zoom launches can't be any worse than gyro on an aerobatice IMAC plane right??

:O
mithrandir is offline Find More Posts by mithrandir
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Why no emphasis on zoom? Mad Mitchie 88 Aerial Photography 12 Jan 04, 2014 01:29 PM
Discussion Radio Controlled zoom lens Sony Nex5 fpvmodels Multirotor Talk 4 Dec 29, 2013 05:35 PM
Discussion Aomway 10 x Zoom Camera 700 TVL Dogdude FPV Equipment 7 Dec 23, 2013 02:49 AM
Sold NTSC 10x Zoom Camera $220 BloomingtonFPV FPV Equipment (FS/W) 0 Nov 27, 2013 08:49 PM
Discussion FAI F5J , ALES and eSOARING ZOOM TOOL Painter S Electric Competition Soaring-F5J/ALES/e-Soaring 10 Oct 13, 2013 07:10 AM