Is the 200ft below Min Finish Height Rule Working?

I think Hank may have missed the main point of the article. The author is not proposing to lower the finish height, on the contrary, he would raise it. The issue centers on the penalty that seems to have the opposite effect of the intent of the rule.

I notice that all of the pilots in the examples started final glide with normal margins for safety. We can presume that the majority of pilots in these races finished above the MFH with no problems. The next crash pilot will not be among them, but the same could be said for a zero finish height. We all try to be safe in this sport and few start out to be low at the finish. The problem comes when we did everything right but conditions change in front of us and degrades the final glide to a point where we are faced with the conundrum of a big penalty or a hail mary.

Seems to me that if we make the penalty for finishing below MFH too high, we only increase the temptation to try the hail mary. Take the rule’s logic further and increase the penalty even more. Says the logic, “that will make people start final glide even higher and fewer people will finish low”. If we simply make the MFH high enough, there is little reason to have any penalty, since there would be little chance for an unsafe entry into the pattern. While that may be true, the problem occurs with those pilots who find themselves in deteriorating conditions that exceed their safety margin established in the final thermal. The counter logic offered by the author admits that the more valuable the finish, the more willing a contest pilot will be to try and pull off a save. Suppose the penalty for a 200´low finish was disqualification from the contest. Would not that cause more otherwise sane pilots to bow to the option of trying to pull it out with a low save?

On the other hand if the penalty were more modest, a hurt but still recoverable, discretion would drive one to accept the penalty and live to compete the next day. I agree with the author that the rule should include a higher MFH but with less of a penalty, thereby placing a lower value on missing the MFH. An additional point in favor of a less costly penalty, it helps the pilot focus on the pattern ahead rather than the altimeter.

There should be some penalty for a low finish but so not big as to give an incentive to attempt a last-mile save. Perhaps a bonus for finishing a bit high creates more value on that side of the line and promote more safety.

Why not use the total height?

So height (AGL) plus potential height (speed²/(2*a)) That makes ballistic pull-ups useless, allows, actually favors smooth finishes.

Then set the total height rather high and substract one point per feet too low.

On Monday, January 20, 2014 3:03:41 PM UTC-5, J. Nieuwenhuize wrote:
Why not use the total height? So height (AGL) plus potential height (speed²/(2*a)) That makes ballistic pull-ups useless, allows, actually favors smooth finishes. Then set the total height rather high and substract one point per feet too low.

Simply put- because this becomes a pilot and scoring nightmare. Note that each glider converts kinetic energy to potential energy differently.
UH

On Monday, January 20, 2014 2:21:11 PM UTC-6, wrote:
On Monday, January 20, 2014 3:03:41 PM UTC-5, J. Nieuwenhuize wrote:

Why not use the total height? So height (AGL) plus potential height (speed²/(2*a)) That makes ballistic pull-ups useless, allows, actually favors smooth finishes. Then set the total height rather high and substract one point per feet too low.



Simply put- because this becomes a pilot and scoring nightmare. Note that each glider converts kinetic energy to potential energy differently.

UH

UH answer is deep -- pay attention.

RC gets two constant demands. One, as in the original post, is to add carefully constructed point carpentry around the finish, with 10 points for this and 20 points for that. The other is to simplify the rules, and especially to make sure pilots don't need to do lots of strategizing and in-air calculations. As you come up with alternatives, make sure they satisfy simplicity and clarity too!

John Cochrane

On Monday, January 20, 2014 1:39:11 PM UTC-8, wrote:

RC gets two constant demands. One, as in the original post, is to add carefully constructed point carpentry around the finish, with 10 points for this and 20 points for that. The other is to simplify the rules, and especially to make sure pilots don't need to do lots of strategizing and in-air calculations. As you come up with alternatives, make sure they satisfy simplicity and clarity too!

John Cochrane

This particular issue has received scores of hours of thought, debate and analysis, including just about every conceivable scenario from the beginning of a final glide (below, at, and above optimal Mc final glide OR best L/D glide to the finish) and every major decision scenario as glides go bad (or don't get better - including able to make the cylinder but not the airport, vice-versa and under different penalty structures) ALSO various lift scenarios (none, less than current Mc, and climb rates all they way down to climbs so slow you are losing speed points faster than you lose penalty points). Zoomies at the edge, terrain in the last 10, 5 and 1 miles to the airport, proximity to a ridge, number of runways, configuration of the approach versus the finish, trees at the end of the runway and number of competitors trying to land at once with how much energy. It ALL gets assessed and debated, including the bizarre potential choices pilots might make (although pilots can be very creative in coming up with bizarre things - the analysis did include low circling to get up to finish height even right up to the edge of the cylinder). Then what gets discussed is which are likely versus unlikely scenarios and which ones are pilot decision issues versus places where the rules beg the pilot to take a chance in order to score more points. LASTLY it all gets put into the filter of don't change anything and make it simple (against the tide of requests for specific exceptions to handle odd cases).

In this case the higher order issues boiled down to: 1) The rules should not be set up to award points to pilots who cross the finish cylinder at an altitude from which it is unlikely that (s)he can safely reach the airport (including scenarios with the runway not lined up, into the wind and with trees), 2) Assess a modest penalty for most common glide gone wrong errors, such that a pilot would not ignore a reasonable-looking climb along the way on a marginal glide to MFH.

If you do the math what you find is if you allow (as we do) different finish heights and different sized finish circles you can end up with not much room between the bottom of the mild penalty and "can't get to the airport" height. A penalty structure that varies the steepness of the penalty depending on the cylinder radius and MFH is possible, but complex and was set aside as was restricting the finish height to 1000' or above as some sites with ridges like the flexibility to finish right off the ridge.

It's mostly documented in the RC notes. I'd be happy to take anyone through the "all the scenarios" analysis offline - there's a lot to think about before you boil it down to a set of simple rules and it's easy to fix one thing while braking something else.

9B

On Monday, January 20, 2014 6:37:18 PM UTC-5, wrote:
On Monday, January 20, 2014 1:39:11 PM UTC-8, wrote:



RC gets two constant demands. One, as in the original post, is to add carefully constructed point carpentry around the finish, with 10 points for this and 20 points for that. The other is to simplify the rules, and especially to make sure pilots don't need to do lots of strategizing and in-air calculations. As you come up with alternatives, make sure they satisfy simplicity and clarity too!



John Cochrane



This particular issue has received scores of hours of thought, debate and analysis, including just about every conceivable scenario from the beginning of a final glide (below, at, and above optimal Mc final glide OR best L/D glide to the finish) and every major decision scenario as glides go bad (or don't get better - including able to make the cylinder but not the airport, vice-versa and under different penalty structures) ALSO various lift scenarios (none, less than current Mc, and climb rates all they way down to climbs so slow you are losing speed points faster than you lose penalty points). Zoomies at the edge, terrain in the last 10, 5 and 1 miles to the airport, proximity to a ridge, number of runways, configuration of the approach versus the finish, trees at the end of the runway and number of competitors trying to land at once with how much energy. It ALL gets assessed and debated, including the bizarre potential choices pilots might make (although pilots can be very creative in coming up with bizarre things - the analysis did include low circling to get up to finish height even right up to the edge of the cylinder). Then what gets discussed is which are likely versus unlikely scenarios and which ones are pilot decision issues versus places where the rules beg the pilot to take a chance in order to score more points. LASTLY it all gets put into the filter of don't change anything and make it simple (against the tide of requests for specific exceptions to handle odd cases).



In this case the higher order issues boiled down to: 1) The rules should not be set up to award points to pilots who cross the finish cylinder at an altitude from which it is unlikely that (s)he can safely reach the airport (including scenarios with the runway not lined up, into the wind and with trees), 2) Assess a modest penalty for most common glide gone wrong errors, such that a pilot would not ignore a reasonable-looking climb along the way on a marginal glide to MFH.



If you do the math what you find is if you allow (as we do) different finish heights and different sized finish circles you can end up with not much room between the bottom of the mild penalty and "can't get to the airport" height. A penalty structure that varies the steepness of the penalty depending on the cylinder radius and MFH is possible, but complex and was set aside as was restricting the finish height to 1000' or above as some sites with ridges like the flexibility to finish right off the ridge.



It's mostly documented in the RC notes. I'd be happy to take anyone through the "all the scenarios" analysis offline - there's a lot to think about before you boil it down to a set of simple rules and it's easy to fix one thing while braking something else.



9B

Clearly there was a big departure from gradual penalty to the land out penalty. Big change that moved the dangerous flying outside the finish cylinder.. Why the land out penalty. I don't think the land out penalty was well thought through.

The land out penalty should be rolled back and gradual penalty should come back if any.

Rules can't fix stupid. For each reiteration of the rule set we pilots
will find a way to do something stupid with them, and so we spiral down
the rabbit hole of never ending rule changes that become more complex
every year. In my opinion the rules should be as simple as possible.
They should not promote dangerous behaviour, but their primary objective
is to provide a fair way to determine the best pilot. The simpler the
rules the more time the pilot has to worry about flying the aircraft.


Luke Szczepaniak

I can appreciate Hank Nixon’s idea that the rule should be clear and simple. I have little background in this particular issue but what I have not seen yet is the data that supports a fixed 200-foot penalty zone as opposed to some other number between the MFH and the land out. The only thing I see in the rule notes is that the 200’ value was established to accommodate instrument error.

As I understand A10.9.2.2, the CD determines the altitude at one mile from which a safe landing at the contest airport can be made (normally considered 500’ plus adjustments for other traffic, terrain etc). The rule establishes the MFH as that altitude plus 200’ and requires all pilots to finish at MFH or incur a penalty that is graduated over 200’. A finish at MFH minus 201’ is scored as a land out, thereby costing as much as 400 points.

If the goal of the rule is to prevent low-save attempts near the airport, why not increase the “penalty-zone width”, (my term) from the current 200’ to say, for example, 500’ and spread the penalty points out over the 500’. If most pilots start the final glide with MFH + glide alt required + 500 margin, then the FG would have to degrade to the point that the pilot suffers a loss of an extra 1000’ before going below the land-out altitude at 1 mile.

If this rule were implemented for the 2014 season, there might well be an increase in finish penalties but there should be a marked decrease in low-save attempts on FG or land-out attempts resulting from them. Following John Cochran’s point, I expect that most pilots would accept a small penalty rather than attempt a risky save. If my expectations prove to be supported by future data analysis, then the administrative land-out part of the rule might be rendered obsolete.

The other point I would make is that even a small finish penalty (FP) collected many times will significantly reduce a pilot’s competitive standing. Eventually, even the slow-thinking racers will figure out that they are better off coming in a bit high than a bit low.

Seems to me that simply increasing the size of the “penalty zone” from 200’ to a larger value, say 500’, satisfies everyone. It is simple and clear, easy to implement, increases safety, and reduces the incentive to attempt a low save near the airport.

BZ

On Tuesday, January 21, 2014 2:53:44 PM UTC-5, Bravo Zulu wrote:
I can appreciate Hank Nixon’s idea that the rule should be clear and simple. I have little background in this particular issue but what I have not seen yet is the data that supports a fixed 200-foot penalty zone as opposed to some other number between the MFH and the land out. The only thing I see in the rule notes is that the 200’ value was established to accommodate instrument error. As I understand A10.9.2.2, the CD determines the altitude at one mile from which a safe landing at the contest airport can be made (normally considered 500’ plus adjustments for other traffic, terrain etc). The rule establishes the MFH as that altitude plus 200’ and requires all pilots to finish at MFH or incur a penalty that is graduated over 200’. A finish at MFH minus 201’ is scored as a land out, thereby costing as much as 400 points. If the goal of the rule is to prevent low-save attempts near the airport, why not increase the “penalty-zone width”, (my term) from the current 200’ to say, for example, 500’ and spread the penalty points out over the 500’. If most pilots start the final glide with MFH + glide alt required + 500 margin, then the FG would have to degrade to the point that the pilot suffers a loss of an extra 1000’ before going below the land-out altitude at 1 mile. If this rule were implemented for the 2014 season, there might well be an increase in finish penalties but there should be a marked decrease in low-save attempts on FG or land-out attempts resulting from them. Following John Cochran’s point, I expect that most pilots would accept a small penalty rather than attempt a risky save. If my expectations prove to be supported by future data analysis, then the administrative land-out part of the rule might be rendered obsolete. The other point I would make is that even a small finish penalty (FP) collected many times will significantly reduce a pilot’s competitive standing. Eventually, even the slow-thinking racers will figure out that they are better off coming in a bit high than a bit low. Seems to me that simply increasing the size of the “penalty zone” from 200’ to a larger value, say 500’, satisfies everyone. It is simple and clear, easy to implement, increases safety, and reduces the incentive to attempt a low save near the airport. BZ

I'm unclear by what BZ describes whether he is suggesting raising the top(1000 ft finish with 500 ft landout threshold, or lowering the bottom. Clearly the latter is less safe.
The 2014 rules changes reflect no changes in finish rules or scoring.
This general topic, not focused on this one sub set of the issue, was polled in 2013. One option described was a larger range over which score reduction might occur. Given no poll mandate for quich change, and mindful of the effect that changes have, the RC, wisely in my view, elected to stand pat for now.
The issue of pilots circling up tp avoid a land out score seems, to me, to be small compared to the overall safety benefit of the rules as currently used.
Sean raised this as a useful discussion point. Maybe some folks will understand a bit more about this now.
FWIW
UH

Hank Nixon wrote:
I'm unclear by what BZ describes whether he is suggesting raising the top(1000 ft finish with 500 ft landout threshold, or lowering the bottom. Clearly the latter is less safe.

I am not suggesting that the RC lower the bottom but rather raise the top of the “penalty zone”. As I read the RC notes concerning proposed rule changes on the SSA website, it says in part:
Guidance Revised: Setting Minimum Finish Height
This amends the guidance to highlight the need to consider additional factors

The notes suggest to me that the CD has great latitude on setting the MFH depending on the competition site and other considerations. It defines the MFH as “the minimum height for a penalty-free finish.” The notes continue, “Because a valid finish (with a very small penalty) may be up to 200’ below the MFH (to accommodate instrumentation errors),it is this lower height that should be considered when setting the MFH. Thus in the absence of
landability, traffic, or other concerns, the MFH should normally be 700’ AGL at a mile, which
avoids creating a big step in points (landout rather than speed finish) at 300 ft AGL leaves even
the lowest valid finisher with 500’ for a pattern and landing.

I read that is the minimum altitude to avoid a land out is “normally 500’ with a “penalty zone” of 200’ more. I am simply suggesting that the rule could be improved by adding 300’ to the fixed 200’ as a “penalty zone”. That would preserve the accommodation for instrument error and add an additional measure of safety. It would also make the accumulation of penalty points for a slightly low finish more gradual. My suggestion of a 500’ “penalty zone” was just an example. The RC could pick another number if it were more efficacious. The bigger it is the more gradual the accumulation of penalty points would be. The effect is that for a small error in arrival height there is less incentive to attempt a low save. Finding oneself 200’ lower that intended is more likely than being 500’ lower.