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Fair winds to all.

2016-06-05 17:17:14

Re: qTVlm 5.3.5 output bug.

Board » Technical Support

The other bug (bigger) is that the new qT version dosen't read correctly the boat polar data.

Attached Polar from the VOR70 read by qT.
Fair winds to all.
2016-06-05 12:52:46

qTVlm 5.3.5 output bug.

Board » Technical Support

Viva all.

The headers in the CSV output file are not displayed correctly.
The attached CSV file shows the problem.
Fair winds to all.
2016-05-17 13:30:52

Re: #4 simple question to Phillipe/maitai.

Board » Technical Support

Viva Philippe.

Thank you for your reply but it didn’t clear out my doubts. By the contrary.

I knew/know that qT used/uses one of the two processes: “Time” or “Distance” Step for calculating consecutive Isochrones.
Hence my questions on previous points 1 and 3.

As you know, if the process is a “Time Step” one, we have to use “Time” units for it, (seconds, minutes, hours, etc.).
But, if the process is a “Distance Step” one, the units are “Length” (meter, km, nautical miles, etc.).

In your reply you mix the “internal time step” (sic, I assume that it is in “Time” units) with a “minimum” of “1 nm” for the calculations (I assume it is in “Length” units), and “5 nm” for the distances between consecutive Isochrones (idem).

At minimum, it’s not physically congruent, Philippe.
Or you use time or you use distance. Not both at the same time.

Meanwhile I’ve made a small test with qT - pls see attached picture.
In top of a trivial routing I’ve put two marks, the first at the distance made by the boat on 1 minute and a second mark at a distance made in 5 minutes, this one on top of the first shown Isochrone in the routing.
Well, being an Isochrone calculation what you get in the chart plotter is a representation of the consecutive curves that can be reached at at the same time by a boat travelling at a constant speed between them.
But, again, I’m using here only “time” units (minutes), not “nm” (nautical miles), Philippe.

In relation to your opinion that “is already too small and useless”, the 5 minutes, I totally disagree.
There are several reasons for it. I give you two:

- Light winds;
- Fast boats on tight spaces.

Thank you again, Philippe.
Fair winds to all.
2016-05-13 14:29:35

Re: QT Routes Comparator bug.

Board » Technical Support

Finn, thank you.

psail.
Fair winds to all.
2016-05-13 12:34:08

QT Routes Comparator bug.

Board » Technical Support

In the last qT version the "Routes Comparator" has a description bug.
Instead of having a second "BS average" it should be "TWS Average".
Fair winds to all.
2016-05-13 11:23:41

LP and the Le Cirque du SOL-eil.

Board » Technical Discussion

This is an old SOL issue to which many miles of words have been written, but I felt I had to make some further comments on this subject.

In a brilliant article in this Forum - as always - my friend Jan/”bonknhoot” explained the SOL imposed LP (Loss of Performance) on boat maneuvers and the processes to minimize it Performace Loss.

The real problem here isn’t the “LP” figure itself, i. e., the percentage of Boat Speed (BS) you lose after making some boat maneuvers - in that respect it’s like the real world at work - but, the enormous amount and unrealistic time you take for recovering the full BS boat potential (according to the boat Polar).

The LP problem is strongly aggravated as the BS increase. The faster you go the bigger the time penalty you get after the maneuver. It ruins all good gybing/tacking tactics you may want to use.
When the BS is slow (one example: Tall Ships races), you can still tack/gybe forever without any especial penalty, if not, any at all. We have here a clear exception to the sought effects of the LP rule.

Forgive me Jan but, I can’t resist concluding: with some acrobatic moves and the same number of boat pirouettes, you can in fact “elude” to some extent the LP monster.
With tons of good reasons I’m hearing now the crowd shouting:
Circus comes to water!

I speak for myself as being also part of these fast growing “artistic movement “.
Using all this plethora of tricks, or better, acting “performance”, we are clearly outside one of SOL goals: to get as close as possible to reality.
At the present state, all we have is an obvious invitation for doing bad sailing and, if you don’t believe what I’m saying, please see the attached picture of a “square root” (!) gybe from one of the top boats on the ongoing Iceland TR.

Trying to solve a problem - to penalize the extra boat maneuvers (only) in certain conditions - SOL created a bigger one, IMHO.

Hence my suggestion to SRC.
Stop that frustrating rule and enforce good sportsmanship behavior for the faulty ones.

Fair winds to all.
2016-05-13 10:49:09

#4 simple question to Phillipe/maitai.

Board » Technical Support

Viva all.

And the questions are:

1 - Does qT uses Time Steps (TS) (in time units) calculations for the Isochrones calculations?
2 - If yes, is it 1 minute the minimum TS?
3 - If it doesn’t use TS for Isochrones calcs, does qT use Distance Step (DS) (in distance units)?
4 - In that case is 1 nm the minimum DS?

Thank you.
Fair winds to all.
2016-05-09 14:50:42

Re: First 44.7 Polar

Board » Technical Support

Viva Roddo and all.

Atttached goes the FIRST44.7 Poalr data in the qTVlm format (diferent from the one used for SPINNACER).
Fair winds to all.
2016-05-04 11:50:52

qTVlm wish list - Part II.

Board » Technical Support

The last qT update (vers. 5.3.1) brought great improvements to the program.
Congratulations Phillipe/maitai.

There are still some aspects that can be improved.

1 - Separate files and/or a race data base.

1.1 - “Barriers”.

A Large part of the racing preps is to lay out “barriers”.
You invest a lot of time to trim those polylines so latter you can shorten the time used on calcs, namely.
It would be appropriate to have the possibility to save/export those “barriers” on a separate file and latter load/import it to the chart plotter. But not on the “poiReal.dat” file, as it goes now.

Still in the barriers. While the “Close” barrier option exists, the “Open” one is not available.
It should.

1.2 - User Waypoints/Marks.

Other part of your preps is to place (user) Waypoints or race specific Marks, whatever.
The same wish for the “barriers” applies here: separate files for saving the points coordinates.

1.3 - Race database.

The ideal was the possibility for creating races database in which you could gather all the above mentioned data and other like the routes made during each race.

2 - Route output CSV file.

2.1 - Unit symbols used on the output file: “kts, “NM” and “º”.

Those units’ symbols should be created on a second separate row (under the first one).
You spend a lot of time - even using the find/replace tool - cleaning those units’ symbols that are extensively repeated for nothing.

2.2 - Customable output file columns.

At least #10 columns on the generated route output file (CSV) don’t have any use for SOL purposes, to know:
- Sail/Engine; SOG; COG; AWS; AWA; CS; CD; COMB WAVES HGT; MAX WAVES HGT; MAX WAVES DIR.
It would be appropriate the user to choose which columns would be generated on the CSV file.

3 - The “crank” confusion.

There’s a big confusion about the “crank” term.
It’s used for changing the Polar size on the chart plotter (associated with “Reckoning”) and also for the Time/Distance Steps routing calculations.
My suggestion is: to use a different term (not “cranck”) and explain in the menus if qT is routing using Time Steps or Distance steps for generating the Isochrones.

With this accomplished qT starts to be a very serious router. Believe it.
Fair winds to all.
2016-05-02 09:35:28

Re: SYC Burgee

Board » General Discussion

Viva Huib,

Many happy hours and fun at the new 5 helm’s is my wish!
Fair winds to all.

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