It's worth looking at how sailing tried handicapping 20 years ago, as they went
through a similar process. I was heavily involved both as a competitor and as
someone trying to make the system work.
Some bright individuals came up with the idea of handicapping based on a polar
so that the wind conditions were taken out of the results - heavy boats do
better in strong winds, light boats do better in light winds on a fixed
handicap (in general).
There were 2 ways of working this. The way commonly used was similar to the ME
system, in that the polar was used to generate an apparent wind and the highest
wind won. This was almost universally hated by the sailers, but loved by the
organisers, so it prevailed - until the sailers moved to other classes. The
biggest problem is that as there was no actual handicap in use, it was
impossible to work out how you were doing during the race.
The alternative was to calculate the handicap (in seconds from a scratch boat)
based on the exact course and the actual (and forecast) wind conditions. This
was also able to factor in the tide, which could have a huge impact. Given 15
boats, we could get the handicaps calculated and broadcast to the boats in
about 5 minutes. This was loved by the sailers who used it, but panned by the
main race organiser, mostly because they had invested so heavily in the first
option.
Right now, sailing has moved completely back to a fixed number handicap the
same as we use - it's not the theoretical optimum solution, but in practice, it
works better than anything else ! Easy to use, easy to understand and very few
complaints.
When you look in detail at comp results, there is very little difference
between strong days and weak days in terms of the types that win. Actually, you
could score most recent standard and 15m nationals with no handicap and get the
same results, even though in 15m the winners are flying older or un-flapped
gliders. In other words, it's obvious that differences in pilot ability is far
greater than any inaccuracy in the handicaps we are using !
On 07/03/2013, at 23:56 , Mike Cleaver <wom...@netspeed.com.au> wrote:
> Hi Terry (and congratulations on your IGC role, and work winning Worlds for
> Australia)
>
> The handicap system was devised by Peter Rigby of the Wollongong Gliding
> Club, and more recently maintained by a committee chaired by Graham Brown of
> Bathurst SC. In essence, the committee agree on a polar for each glider,
> then use it to predict theoretical cross-country speed on a closed circuit
> task in nil wind, on a day when the thermals are all a nominal "Standard
> Australian Thermal" of a given diameter and lift cross-section. It is a
> similar system to the BGA one but our thermal is bigger and stronger than
> theirs!! :-))
>
> We now use two sets of handicaps, one for ballasted gliders and the other
> without ballast (i.e. dry) for club and sports class comps. There is a glider
> type (currently the LS4) that is assigned a handicap of 100.0% and other
> types are scaled relative to this one to produce the final handicap figure.
>
> The Murray Evans system did almost a reverse of this process - it worked from
> the achieved speed to input to the polar curve and determine the actual
> thermal strength used - scoring could then be done to award the daily maximum
> points to the pilot who used the best thermals (or who used streets to best
> advantage or cruised in rising air to the greatest extent). This has the
> advantage of automatically adjusting for wind on the day, the greatest
> failing of the standard handicap. In the UK nowadays, or last time I looked,
> they actually change the handicaps on a daily basis depending on the observed
> wind for the task, so higher performance gliders do not get an inbuilt
> advantage on windy days and lower performance gliders are not penalised by
> the wind. However, this still does not overcome Peter R's problem that to
> complete a fixed task, he has to fly for a longer time and thus risk having
> to use weaker lift than his competitors who only use the stronger past of the
> day. Hence the idea of the variable task which developed into our current
> form of AAT.
>
> So some pilots spend a lot of time, effort and money working on their glider
> to try and make it perform better than others of the same type, and
> handicappers invent factors for winglets, turbulators and actual wing
> loadings of lighter pilots flying unballasted - but nobody yet regularly uses
> a reference thermal that reflects the actual conditions on the day, or the
> fact that some sites experience consistently better thermals than others.
>
> Pilot-based handicaps sounds more like golf than flying!
>
> Wombat
>
>
> On 7/03/2013 11:06 PM, Terry wrote:
>>
>> The ME formula was used for many years, but it was used to compare results
>> across classes for team selection, not handicaps. ME would apply the formula
>> to produce a team solution and then some "wise" heads would critique and
>> then ME would "adjust" the factors and produce a new set of results.
>> Eventually an answer was agreed. The most subjective objective process.
>>
>> Handicaps were formulated by another member (? Brown?) who spent a lot of
>> personal time reviewing polar curves and calculating thermal characteristics
>> to calculate the "right" handicap. The concept was good but Unfortunately,
>> the polar curve data was from many sources and therefore no consistency. The
>> first club class I went to the pilots spent the whole two weeks arguing
>> about handicaps.
>>
>> We then invited another group of wise heads to use their experience and
>> invent some handicaps. Since that time, there have been very few issues with
>> handicaps. It is not an exact science.
>>
>> At Gawler we now use Pilot handicaps also , which is even less scientific,
>> but good fun. A little retrospective adjustment resolves any errors.
>>
>> Terry
>>
>> Sent from my iPhone
>>
>> On 07/03/2013, at 8:10 PM, <gstev...@bigpond.com> wrote:
>>
>>> Peter,
>>> That is an interesting suggestion! I wonder if it could be practically (and
>>> fairly), done?
>>>
>>> Re "poor" task setting, I tend to think that your objection 'having to
>>> start early/finish late" is actually as a general principle, just the
>>> opposite - at a National level and probably a State level too, this is what
>>> good tasking should be all about! In general, the task setting at most
>>> competitions, on most reasonably soarable days, is far too conservative.
>>> {Everybody, please carefully note those two provisos - "most" &
>>> "reasonably"!}
>>>
>>> Having said that, I tend to agree with your last paragraph, which then gets
>>> back to the question I raised in my first paragraph above.
>>>
>>> The points noted by Matthew Scutter, in his email below, are all reasonable
>>> too. Emilis Prelgauskas in a recent posting on this site, talked (amongst
>>> other things), about some of the problems facing the gliding movement in
>>> this country, including a gradual loss of knowledge held collectively by
>>> the membership, and knowledge (mostly), lost to the current Board and those
>>> administrating the GFA system. Once upon a time - I think it was just
>>> around the time of the introduction of computers into gliding scoring - a
>>> guy called Murray Evans (Murray-Evans?), came up with a system that related
>>> everybody's performance back to their glider polar, and the results for the
>>> day were then "corrected". The system was tried once, and promptly
>>> abandoned, as being unworkable - which was fair enough at the time. The
>>> first and possibly major problem then, was obtaining realistic polars, for
>>> the gliders competing. Number crunching (laughable today), was also a
>>> problem, as I recall. In my view, it might now prove profitable to revisit
>>> the principles of the ME concept, and check their workability in the
>>> current hi-tek environment.
>>>
>>> Ann Woolf - given the tremendous (mind boggling?) - work that you have done
>>> on compiling the electronic AG data base - could I please call upon you to
>>> put the article(s?), that appeared in Australian Gliding, on this web
>>> site, for the perusal and comment of a latter generation of glider pilots?
>>>
>>> Gary
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